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ILLINOIS POLLUTION CONTROL BOARD
August 22, 2006
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3 IN THE MATTER OF:
4 PROPOSED NEW 35 ILL. ADM. CODE PART 225 ) R06-25
CONTROL OF EMISSIONS FROM
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5 LARGE COMBUSTION SOURCES (MERCURY)
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REPORT OF PROCEEDINGS held in the
8 above-entitled cause before Hearing Officer Marie
9 Tipsord, called by the Illinois Pollution Control Board,
10 taken before Laura Bernar, CSR, a notary public within
11 and for the County of Cook and state of Illinois, at the
12 James R. Thompson Center, 100 West Randolph Street,
13 Chicago, Illinois, on the 22nd day of August, 2006,
14 commencing at the hour of 9:00 a.m.
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1 A P P E A R A N C E S:
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SCHIFF, HARDIN, LLP
6600 Sears Tower
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Chicago , Illinois 60606
(312)258-5646
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BY: MS. KATHLEEN C. BASSI
MR. STEPHEN J. BONEBRAKE
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MR. SHELDON A. ZABEL
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Appeared on behalf of the Dynegy and Midwest
Generation;
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ILLINOIS ENVIRONMENTAL PROTECTION AGENCY
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1021 North Grand Avenue East
P.O. Box 19276
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Springfield, Illinois 62794-9276
(217)782-5544
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BY: MR. JOHN J. KIM
MR. CHARLES E. MATOESIAN
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ILLINOIS POLLUTION CONTROL BOARD:
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Ms. Marie Tipsord, Hearing Officer
13 Ms. Andrea S. Moore, Board Member
Mr. G. Tanner Girard, Acting Chairman
14 Mr. Anand Rao, Senior Environmental Scientist
Mr. Nicholas J. Melas, Board Member
15 Mr. Thomas Fox, Board Member
Mr. Thomas Johnson, Board Member
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1
HEARING OFFICER TIPSORD: Good morning. My
2 name is Marie Tipsord, and welcome back everyone. This
3 is Day 7 of the second set of hearings and we're moving
4 right along. I believe today starting with Dr. Peter
5 Chapman and then we'll go to Gail Charnley and after
6 that we'll see. At this time can we have Dr. Chapman.
7
(Witness sworn.)
8
MR. BONEBRAKE: Madam Hearing Officer, I
9 would tender a copy of Mr. Chapman's written testimony.
10
HEARING OFFICER TIPSORD: If there's no
11 objection we'll mark Dr. Chapman's prefiled testimony as
12 Exhibit
No. 129. Seeing none, it's Exhibit 129.
13
MR. BONEBRAKE: I believe Mr. Chapman was
14 going to open with a short introduction, then he'll
15 follow with his responses to the questions of the
16 Agency, and then a couple of questions from Prairie.
17
HEARING OFFICER TIPSORD: Great. Thank you
18 very much. Go ahead, Dr. Chapman.
19
THE WITNESS: Thank you very much, Madam
20 Chair, Members of the Board, Counsel, members of the
21 audience. My name is Peter Chapman. I received my
22 Ph.D. in 1979. My areas of expertise are in terms of
23 aquatic ecology, ecotoxicology, and ecological risk
24 assessment. I've published about 150 papers and
4
1 scientific literature, and a great number of them
2 concerned with metals including mercury; metals being
3 one of my major areas of expertise and focus over the
4 last many years, and, as you'll see, you'll see the
5 details in my written testimony. I won't go into them.
6
What I'd like to do now is spend just a
7 few minutes summarizing my testimony. Basically what
8 we're looking at is two things: We're looking at
9 inorganic mercury emitted from coal-fired power plants
10 and we're looking at metal mercury or organic mercury in
11 fish. And the whole basis of my testimony is there is
12 not a linear relationship between the two because
13 matters are very complex. My testimony is very well
14 supported by the testimony of others such as Marcia
15 Willhite, which I'll allude to. Basically what happens
16 when mercury comes into the atmosphere is it comes from
17 a variety of sources. When it's in the atmosphere, it
18 can circulate and the sources include anthrogenic, human
19 sources. They also include natural sources. And
20 although the estimates vary, it seems to be more or less
21 general agreement somewhere around 50 percent of the
22 mercury in the atmosphere is natural rather than
23 anthrogenic. You've heard testimony it takes different
24 forms in the atmosphere. I'm not going to get into that
5
1 because I'm going to stick to the biology and what
2 happens and the physical chemical effects when the
3 mercury is deposited in water. From the atmosphere it
4 can be deposited to land or to water in the inorganic
5 form. There's other place, other ways mercury in the
6 inorganic form or sometimes in the methylated form can
7 get into waterbodies. So we have these waterbodies, we
8 have the inorganic mercury here. Once it's there it
9 tends to absorb to particles settled down to the
10 sediments. It's very complex what happens then because
11 in terms of the conversion from the inorganic to the
12 methylated organic form, you need have anoxic
13 conditions, in other words, no oxygen. This doesn't
14 occur in all waterbodies. You won't find this in most
15 water ponds. You'll find this in certain sediments. It
16 needs bacteria to produce this, and the process is
17 regulated by a whole variety of circumstances that were
18 well described by Marcia Willhite in her testimony. For
19 instance, pH, selenium, organic carbon, a whole bunch of
20 different factors can regulate whether this mercury
21 actually becomes methylated or not in the sediments.
22 And the amount in the sediments, as Marcia Willhite
23 pointed out correctly in her testimony, of the total
24 mercury that's methylated is very small. It's less,
6
1 generally less than 1 percent, sometimes way, way less
2 than 1 percent. So we have the small amount of
3 methylmercury that can be formed. It can be formed from
4 both recently deposited sediments and from recently
5 deposited mercury and mercury that's been there for a
6 long period of time. From here it can and does get into
7 the food chain and accumulate up to fish, but the
8 problem is that it's a very complex process. We can't
9 say in any way, shape, or form that if you've got "X"
10 amount of inorganic mercury deposited from any source,
11 let alone from one source into a waterbody, it'll
12 produce this amount of methylmercury in fish.
13
In terms of the Illinois data, we went
14 to the data bases, and you'll see in my testimony
15 there's a couple of figures and a couple of tables.
16 What we looked at was the total mercury which would
17 include the methylmercury in sediments and tried to see
18 if there was a relationship between that and the
19 methylmercury in fish. And we couldn't see a
20 relationship. Now, grant it the data are not extensive
21 and there's a lot more text, but we used available data.
22 We also tried to take a look and see if the
23 methylmercury concentrations in fish could be related to
24 where the power plants were using information where
7
1 prevailing wind currents were coming from, and we
2 couldn't see a relationship. And that's not surprising,
3 because I mentioned, mercury comes from a whole variety
4 of sources. It's a global issue. It's not just an
5 Illinois issue.
6
Finally, we looked at the issue of if
7 mercury concentrations decreased, low levels that in
8 Illinois indicate impairment, would you still be able to
9 eat the fish, and the answer is no because PCBs would
10 still be an issue. So that summarizes very briefly my
11 testimony. What I'd like to do now, if it's okay with
12 the Board, is proceed with the first questions. I'd
13 like to proceed with the IEPA questions, if I may.
14
HEARING OFFICER TIPSORD: Go ahead.
15
THE WITNESS: Shall I read the question?
16
HEARING OFFICER TIPSORD: Yes. Read the
17 question and then the response. Thank you.
18
THE WITNESS: Question 1: Under section
19 2.0 on Page 2 of your testimony, you state, "The goal of
20 the proposed rule, as summarized in Marcia Willhite's
21 written testimony at Page 4 ("in order to ensure that 95
22 percent of largemouth bass in Illinois waters may be
23 consumed by sensitive subpopulations, a 90 percent
24 reduction of mercury in fish tissue is needed") will not
8
1 had be achieved." Is your statement consistent with
2 other testimony on this issue as provided by Jim Ross in
3 testimony provided on June 19, 2006, at the hearing held
4 in Springfield (as found on Page 127 of that day's
5 transcript)?
6
My statement is consistent with Marcia
7 Willhite's testimony which this references. As to
8 whether my written testimony is consistent with Jim
9 Ross's verbal testimony, quite frankly I've read and
10 reread his verbal testimony, and I'm not sure what he's
11 saying.
12
HEARING OFFICER TIPSORD: Question No. 2.
13
MR. KIM: Dr. Chapman, your reading of
14 Marcia Willhite's testimony, do you read that to mean
15 that you believe her testimony was that she was stating
16 that there's a one-to-one correlation between percent
17 reduction of mercury and then a resulting percent
18 reduction of mercury found in fish tissue?
19
THE WITNESS: That seemed to be what she was
20 saying, but then it got confusing because there seemed
21 to be contradictions and we seemed to be going instead
22 of one-to-one to a corresponding decrease, and I wasn't
23 sure what corresponding meant. So I got kind of
24 confused on that issue.
9
1
MR. KIM: So but when you say that -- So
2 when you say your reading of the one-to-one correlation,
3 that's essentially your take of Ms. Willhite's testimony
4 as provided in written prefiled form; is that correct?
5
THE WITNESS: That is correct.
6
MR. KIM: Thank you.
7
MR. HARLEY: Good morning. My name is Keith
8 Harley. I'm an attorney for an organization called
9 Environment Illinois. Dr. Chapman, Question 1 in your
10 testimony characterizes the question that's posed to you
11 as whether or not reducing inorganic mercury emission
12 from coal-fire power plants will lead to the same
13 reduction in fish; is that correct?
14
THE WITNESS: That's correct.
15
MR. HARLEY: So if we were to get a 50
16 percent reduction in mercury emissions from coal-fired
17 power plants, would we see a 50 percent reduction in
18 mercury fish tissue samples; is that correct?
19
THE WITNESS: That's basically the
20 one-to-one.
21
MR. HARLEY: That's the question that was
22 posed to you?
23
THE WITNESS: Okay. The question -- No.
24 Let me clarify. Question 1 simply asks if my statement
10
1 is regarding Marcia Willhite's testimony.
2
MR. HARLEY: I'm sorry. I'm referring to
3 Page 2 of your prefiled testimony.
4
THE WITNESS: Oh, I'm sorry. Could you
5 repeat?
6
MR. HARLEY: The question that was posed to
7 you is will reducing mercury emissions from coal-fired
8 power plants result in the same proportional reduction
9 of mercury reductions in fish tissue; is that correct?
10
THE WITNESS: That's correct.
11
HEARING OFFICER TIPSORD: Excuse me, Mr.
12 Harley. For clarification in the record, the question
13 that you're referring to is the actual question that is
14 posed in Mr. Chapman's testimony, not the prefiled
15 questions.
16
MR. HARLEY: Thank you for clarifying that.
17
THE WITNESS: Thank you. I was confused as
18 well.
19
MR. HARLEY: Dr. Chapman, where did that
20 question come from?
21
THE WITNESS: I posed that question.
22
MR. HARLEY: Did you pose the question to
23 yourself whether any reduction would be seen in fish
24 tissue based on reductions of mercury emissions from
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1 coal-fired power plants.
2
THE WITNESS: I didn't pose that specific
3 question because --
4
MR. HARLEY: Thank you, Dr. Chapman.
5
HEARING OFFICER TIPSORD: And why didn't you
6 pose that question?
7
THE WITNESS: That's what I was going to
8 answer. Because when I looked at the written testimony,
9 what I got from that was that the State was looking at a
10 one-to-one reduction. They were looking for linear
11 reduction. They were quoting the Florida studies, and
12 it seemed to me fairly apparent that if you got an "X"
13 amount reduction in the inorganic mercury from power
14 plants, then you get the same amount of reduction of
15 methylmercury in fish, and that will not occur.
16
HEARING OFFICER TIPSORD: Will there be a
17 reduction in methylmercury in fish, in your opinion, if
18 the air emissions of mercury is reduced?
19
THE WITNESS: It depends on how much of a
20 reduction, how much reduced the air emissions, how much
21 of a reduction you get. But whether you get a
22 measurable reduction is very questionable. So you will
23 you get measurable reduction, but it's a question of how
24 much you reduce and where. Because the problem is that
12
1 as I mentioned mercury is a global issue. And based on
2 looking at Illinois, in some areas of Illinois, it seems
3 that the most of the mercury that may be occurring in
4 the waterbodies and getting to fish is not coming from
5 the power plants. In other areas the winds would
6 indicate that there is deposition occurring. So it'll
7 vary across the state. I can't give a simple answer to
8 this because it's a very, very complex issue.
9
HEARING OFFICER TIPSORD: Mr. Bonebrake?
10
MR. BONEBRAKE: Just a follow-up for
11 clarification, Dr. Chapman. Did you indicate in your
12 written testimony that based upon your understanding of
13 the deposition modeling that had been performed by a
14 gentleman who we'll refer to as Krish and I'll do better
15 with that name than his last name, that you would not
16 expect to see a measurable reduction in fish tissue
17 mercury levels in the State of Illinois?
18
THE WITNESS: That is correct based on his
19 analysis. Thank you for that because I spelled out the
20 name for the court reporter, so Krish is a lot easier.
21
HEARING OFFICER TIPSORD: Go ahead, Mr. Kim.
22
MR. KIM: Just to follow-up on
23 Mr. Bonebrake's question, is it correct to say then that
24 you did not perform any independent analysis of your own
13
1 along the lines of Krish's testimony, and, in fact, you
2 simply did, as you just stated, looked at his testimony
3 and assumed it was accurate and then you based your
4 suppositions from that point forward.
5
THE WITNESS: That is correct.
6
HEARING OFFICER TIPSORD: Now I have to ask
7 the next question. Which suppositions? I mean because
8 as we heard yesterday, I mean he had one set of
9 suppositions for 2010, another set of suppositions for
10 2020. And his modeling showed differing results for
11 2010 and 2020, and different results for CAMR/CAIR
12 versus the Illinois rule. So under all of those
13 modeling?
14
THE WITNESS: The one I took was the
15 additional reduction could be as high as 4 percent of
16 the inorganic mercury emitted. And based on that, my
17 conclusion that you really wouldn't see a measurable
18 difference.
19
HEARING OFFICER TIPSORD: A measurable
20 difference from --
21
THE WITNESS: From the 4 percent. Basically
22 if mercury from the power plants were reduced by an
23 additional 4 percent, the outputs, would you see a
24 measurable decrease in the methylmercury concentrations
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1 in fish in Illinois.
2
HEARING OFFICER TIPSORD: Right. But my
3 question is did -- Is there a difference with the 5
4 percent under CAIR/CAMR, and then you're saying that
5 there is no additional difference between what you get
6 with CAIR/CAMR and what you get with Illinois?
7
THE WITNESS: That's right.
8
MR. RAO: Just for the point of
9 clarification, you mentioned 5 percent reduction in
10 mercury emitted by power plants. Is it emitted or is it
11 what's deposited on the waterbodies?
12
THE WITNESS: I was talking about 4 percent,
13 I believe, not 5 percent.
14
MR. RAO: Deposition, right, not emissions?
15
THE WITNESS: I was talking emissions.
16
MR. RAO: I thought Mr. --
17
THE WITNESS: He was talking about
18 depositions. I'm sorry. You're right. Depositions.
19
HEARING OFFICER TIPSORD: Mr. Harley?
20
MR. HARLEY: But your question that you pose
21 to yourself to answer in your prefiled testimony is an
22 emissions, not a deposition question; is that correct?
23
THE WITNESS: That's correct.
24
MR. HARLEY: And it talks about the
15
1 reduction of emissions, not the reduction of
2 depositions; is that correct?
3
THE WITNESS: That's right. Because that's
4 a first step in the process. And then in my testimony I
5 follow through and looked at deposition and looked at
6 the processes that occurred in the waterbodies.
7
MR. HARLEY: A follow-up question. Already
8 in your testimony you've talked about the high
9 variability in different waterbodies in terms of
10 reduction. And yet you also indicate that there will be
11 no measurable reductions in any waterbody in Illinois
12 based on the data that you reviewed; is that correct?
13
THE WITNESS: No. I didn't say there'd be
14 no measurable reduction in any waterbody. I said
15 there'd be no measurable, and I have to look to see the
16 exact wording, but what I meant is if you're looking at
17 Illinois in general, which is what you're looking at,
18 you're not going to really see a measurable reduction.
19
MR. HARLEY: How is it possible to talk
20 about Illinois in general in reference to waterbodies
21 when waterbodies by definition, according to your
22 testimony, are highly variable.
23
THE WITNESS: Because when you look at it,
24 what you're trying do, my interpretation of the rule is
16
1 you're trying to reduce across Illinois, across the
2 waterbodies, the mercury that's in fish. So there's no
3 longer an issue. That's the major issue, not a single
4 waterbody. So we're looking generically. Certainly,
5 and if you look at the studies, for instance, done in
6 Florida or other locations, you'll see that there's a
7 very great difference between what they found. There's
8 some waterbodies where reductions occurred, some
9 waterbodies where no reductions occurred, and some
10 reductions where concentrations actually increased.
11
MR. HARLEY: In light of the Florida study
12 and in light of the variability of waterbodies, in
13 reference to conditions where methylmercury might be
14 produced, is it fair to say that we might see the same
15 results in Illinois as they saw in Florida: Some
16 reductions, some no effect, and perhaps even some
17 increases in some waterbodies.
18
THE WITNESS: It's possible, but I can't say
19 for sure because one of the problems we have, candidly,
20 is there's not a lot of data. And I'm frankly going to
21 put this gently, quite surprised at the lack of data on
22 which this is all occurring. Because I would have
23 expected there to be a lot more data on where the
24 mercury is coming from, what's occurring, a lot more
17
1 information on the mercury in the waterbodies, and the
2 data really is somewhat sparse for this. So it's
3 difficult with the sparseness of the data and
4 incompleteness of the data to make those sort of
5 conclusions. That's something I would have candidly,
6 again, expected IPA to be following up on to produce
7 more information on that which I haven't seen.
8
MR. HARLEY: Would your own testimony also
9 be more confident if you had had access to more data?
10
THE WITNESS: More data is always good. It
11 depends on which data. Data by itself can often be an
12 oxymoron.
13
MR. HARLEY: Thank you.
14
HEARING OFFICER TIPSORD: Mr. Kim?
15
MR. KIM: Dr. Chapman, when you say that you
16 believe that there's a sparseness of data, that you
17 believe more data should have been collected, are you
18 referring to short-term studies, long-term studies?
19 What exactly is it that -- something akin to the Florida
20 study or the Massachusetts study?
21
THE WITNESS: Well, the Florida study was
22 mainly a modeling study. It wasn't so much a
23 data-gathering study. What I'm looking at are what are
24 the main sources of mercury reaching Illinois? Where
18
1 are they coming from? And I'm not just talking
2 atmospheric. I'm talking other sources such as runoff,
3 waste plants. There's all sorts of different sources
4 where mercury can be coming from. Where are they coming
5 from? And then looking as well to see how this relates
6 to the methylmercury in fish. And a lot of the
7 information we have on methylmercury in fish is
8 information below detection levels where assumptions are
9 being made, detection limit is right, and so on. You
10 certainly haven't characterized all the waterbodies in
11 Illinois in terms of mercury levels and sediments and
12 waters or fish. And I'm not saying you have to do them
13 all, but if you don't have a good cross-section then you
14 don't have a good understanding of what's happening
15 across Illinois.
16
MR. KIM: Do you know how many waterbodies
17 there are in the State of Illinois?
18
THE WITNESS: No, I don't.
19
MR. KIM: Do you know what kind of resource
20 from a financial standpoint would be required to conduct
21 even a cross-section of waterbodies?
22
THE WITNESS: I don't, but I imagine there
23 would be substantial resources required.
24
MR. KIM: Do you have any understanding or
19
1 do you have any guess as to how long it would take to
2 conduct the kind of cross-section and data gathering
3 that you're referring to?
4
THE WITNESS: It would depend on the
5 resources you put to it.
6
MR. KIM: Have you seen the beautiful
7 surroundings of our state agency?
8
THE WITNESS: Do you want me to answer that?
9
MR. KIM: No. I think speaks for itself.
10
MR. RAO: Dr. Chapman, I had a clarification
11 question. In your Question No. 1 on Page 2 of your
12 prefiled testimony, I guess I'm assuming you're talking
13 about that you will not see the same extent of reduction
14 when you, I think to quote it, it says power plants in
15 Illinois under the proposed rule reduced organic
16 methylmercury concentrations in fish living in Illinois
17 waterbodies to the same extent. And when you say same
18 extent, I'm assuming you're talking one-to-one
19 reduction?
20
THE WITNESS: Yes.
21
MR. RAO: But in your opinion will there be
22 some measurable reductions? Because in response to
23 Mr. Harley's question, you said you're not going to see
24 any measurable reductions.
20
1
THE WITNESS: Well, I was talking, in that
2 respect, about the difference between the CAMR and the
3 additional, you know. Because we're talking from
4 Krish's testimony about a 4 percent difference in
5 deposition and in scientific terms we usually lack at
6 significant differences as a difference of 95 percent or
7 so. And so it would be very difficult to, I think,
8 measure that and see that across the state, particularly
9 given how complex a situation is from when inorganic
10 mercury is deposited and sometimes reemitted from
11 waterbodies. It don't always stay there. And the whole
12 process of going through forming the methylmercury and
13 then the methylmercury getting into the fish. It's a
14 very, very complex process we don't fully understand.
15 But there's so many steps, so much variation between
16 waterbodies, that it's -- I don't think there's much
17 science out there to support a one-to-one relationship
18 in any shape or form.
19
MR. RAO: My question was will there be any
20 significant measurable reductions, not one-to-one.
21
THE WITNESS: Okay. Let me clarify. Are
22 you talking about the difference between the rule and
23 what U.S. EPA is proposing, or are you talking about --
24
MR. RAO: The rule itself, the Illinois
21
1 proposed rule. I'm not comparing it.
2
THE WITNESS: You're not comparing it. If
3 you just put in the rule as opposed to -- which
4 includes, you know, what's being done by the CAMR and so
5 on, you will see some reduction. How much I cannot say.
6
HEARING OFFICER TIPSORD: And now I have to
7 ask this: According to Krish's testimony and what we're
8 hearing today, under CAMR in 2010, there will be a 5
9 percent deposition reduction. And you're saying that
10 under the Illinois rule which will include CAMR, you do
11 believe there's going to be a reduction in mercury --
12 methylmercury in fish, correct?
13
THE WITNESS: I think there will be some
14 reduction, yes.
15
HEARING OFFICER TIPSORD: Okay. That's
16 fine. Thank you.
17
MR. KIM: And just as a very general
18 proposition, you would agree that without necessarily
19 going to the specific number, the greater the reduction
20 in mercury emissions, the greater expectation you would
21 have that mercury, methylmercury found in fish tissue
22 would increase. I'm not saying on a one-to-one basis,
23 but I'm saying -- decrease, I mean. Would you agree
24 with that?
22
1
THE WITNESS: What you're talking about is
2 as you reduce inputs, you'll see the amount of
3 methylmercury in fish decrease. It depends, again. You
4 can't say if you reduce it point one percent in the
5 emissions you'll see something measurable. It's a
6 question of, you know, you might actually see some --
7 there might be some reduction that wouldn't be
8 measurable. It would be so tiny. So I just have
9 trouble answering this directly, and I'm not trying to
10 shirk the question, it's just that this is not an easy
11 question to answer.
12
HEARING OFFICER TIPSORD: Which is why there
13 are so many questions.
14
THE WITNESS: I appreciate that, and I hope
15 I'm helping.
16
MR. KIM: I think we'll come back to this a
17 couple of questions down the road.
18
HEARING OFFICER TIPSORD: Question No. 2.
19
THE WITNESS: Question No. 2: On Page 5 of
20 your testimony you state that "methylmercury produced in
21 waterbodies from inorganic mercury can be augmented by
22 direct precipitation of methylmercury from other
23 sources, including: The atmosphere, runoff from land or
24 inputs from other waterbodies such as wetlands." What
23
1 are the sources of methylmercury in the atmosphere, on
2 the land or in other waterbodies?
3
Other sources of mercury that can form
4 the basis for methylmercury production that can augment
5 that in other waterbodies are various and can include,
6 for example, Leksi contamination such as waste dumps,
7 current industrial related sources such as mining and
8 oil processing, alkylate plants, waste from nuclear
9 reactors, pharmaceutical plants, all refining plants,
10 military ordinance facilities, incineration waste,
11 dispose of batteries and fluorescent lamps, medical and
12 dental sources and geological, e.g. natural sources.
13
HEARING OFFICER TIPSORD: Question No. 3.
14
THE WITNESS: Question 3: On Page 6 of your
15 testimony you refer to testimony provided by Marcia
16 Willhite in support of your statement that "runoff may
17 be a significant source of mercury in southern
18 Illinois"?
19
Yes. I specifically reference her June
20 14, 2006 verbal testimony.
21
HEARING OFFICER TIPSORD: Question No. 4.
22
THE WITNESS: Citing to the analysis of
23 mercury in effluent of point source discharges, you
24 emphasize the potential 1.5 ton maximum loading (as
24
1 found on Page 6 of your testimony), isn't it true that
2 to reach the potential maximum loading of 1.5 tons per
3 year state wide, all point sources would have to
4 simultaneously discharge in their maximum level and
5 maximum mercury effluent concentration?
6
First of all, I do not emphasize this
7 potential maximum loading. In fact, I place quotation
8 marks around the word maximum in my written testimony.
9 Although I cannot confirm what's involved in this
10 potential maximum loading, I'm citing the TSD in Marcia
11 Willhite's testimony. My understanding is that this is
12 a maximum value.
13
HEARING OFFICER TIPSORD: Question No. 5.
14
MR. RAO: Just a clarification. Do you
15 expect that maximum value to occur in real life?
16
THE WITNESS: I can't say. I've seen
17 situations where the maximum value, in fact, was not the
18 maximum value and the higher values did occur. And I
19 just don't have the background for all those
20 calculations to determine what might actually occur. So
21 I don't want to postulate.
22
HEARING OFFICER TIPSORD: Question No. 5.
23
THE WITNESS: Regarding footnote 20 at the
24 bottom of Page 6 of your testimony, please describe the
25
1 "available data on mercury related to combined sewer
2 overflow discharges from MWRDGC" and demonstrate how you
3 calculated the loading as being tens of pounds per year.
4
Answer: Note that my correct statement
5 was that, quote, inputs can be on the order of tens of
6 pounds per year, unquote. I examined available combined
7 sewer overflow CSO data from publically available
8 records of the Metropolitan Water Reclamation District
9 of Greater Chicago's, MWRGDGC, Stickney Plant Tunnel and
10 Reservoir Plant, TARP, pumpback records for the years
11 2000 to 2005. Whenever there is a heavy storm event in
12 the city, TARP, T-A-R-P, collects waste water when the
13 primary treatment facilities are overcapacity. This
14 waste water is stored in the tunnel system until such
15 time as it can be pumped back through the treatment
16 plant, treated, and discharged. Although mercury
17 concentrations are not measured in direct CSO
18 discharges, they are measured in water that does not
19 actually overflow but which is to be pumped back for
20 waste water treatment prior to that treatment. These
21 measurements may provide a reasonable approximation of
22 mercury concentrations in other CSOs in the system which
23 do not currently go through any type of treatment prior
24 to direct discharge. These data were used together with
26
1 flow data to estimate the amount of mercury that could
2 be discharged yearly from CSOs during treatment bypass.
3 Average annual concentration data were used. Per IEPA's
4 approach, a value of half the detection was used when
5 data were below detection limits. The MWRDGC web site
6 has flow records available for five of the major CSO
7 points: North branch, Racine Avenue, 95th Street, 122nd
8 Street, and 125th Street. The annual flow from each of
9 these five CSO discharges was calculated. Together with
10 the average annual total mercury concentration obtained
11 from the Stickney TARP pumpback data to calculate what
12 the estimated annual concentration of total mercury
13 would be in all of these five CSO discharges combined.
14 As an example for 2005, the annual average Stickney TARP
15 pumpback total mercury concentration was 0.14 micrograms
16 per liter while a total flow from the five CSOs combined
17 was 2,433 million gallons. Concentration times flow
18 with appropriate conversions, gallons to liters, for
19 example, gives a value of 2.8 pounds per year from these
20 five CSOs. Higher values have been recorded in previous
21 years. For instance, 55.9 pounds per year in 2000.
22 There appears to be a trend of decreasing loadings.
23 However, since both the MWRDGC and the City of Chicago
24 own hundreds of CSOs throughout the Chicago area, a vast
27
1 majority of them unmonitored, and there are likely other
2 CSOs in other areas of the state with similar potential.
3 My statement that quote, inputs can be on the order of
4 tens of pounds per year, end quote, may be conservative
5 it. The intent of this exercise was simply to show that
6 there are likely many sources of mercury input surface
7 waters which were not accounted for by IEPA's analysis.
8
MR. KIM: Dr. Chapman, my understanding is
9 based upon the description of data that you just
10 described that much of this is available to the public,
11 and I would imagine probably a lot of it is available
12 on-line. And I don't know if that's exactly how you
13 acquired the data.
14
THE WITNESS: That is.
15
MR. KIM: I know that you've performed and
16 you gave an example of some basic calculations to come
17 up with the figures that you ultimately made reference
18 to in your footnote. Would it be possible to have a
19 list of the links of the data sets that you used and the
20 calculations that you performed to arrive at your
21 answer?
22
THE WITNESS: Yes.
23
MR. BONEBRAKE: You were asking for web site
24 link information?
28
1
MR. KIM: I'm guessing it's probably a lot
2 of paper, so if it's available on line, I think a web
3 site address is probably sufficient.
4
THE WITNESS: The only thing I'd ask is I am
5 going back to holidays, so if you can wait until early
6 September I'd appreciate it.
7
MR. KIM: That's fine.
8
HEARING OFFICER TIPSORD: Mr. Harley?
9
MR. HARLEY: Dr. Chapman, in developing your
10 testimony, was it your assumption that in order to
11 regulate mercury from coal-fired power plants, the
12 Pollution Control Board would have to regulate every
13 anthrogenic source of mercury that may enter a
14 waterbody?
15
THE WITNESS: No. But if your overall goal,
16 and you need to be clear about what your overall goal
17 is, to reduce the amount of methylmercury in fish in the
18 waterbodies in Illinois, you need, first of all, to
19 determine what all the sources are and then determine
20 which are the ones that are most important to regulate.
21 You shouldn't just make an assumption that is,
22 unfortunately I'll have to see, concur that one source
23 is the only source of mercury. In this case there's,
24 you know, clearly many sources and you need to look at
29
1 it more fully, more holistically.
2
MR. HARLEY: In developing your testimony,
3 was it your assumption that in order to regulate mercury
4 from coal-fired power plants, the Illinois EPA needed to
5 propose and a board needed to enact a rule which would
6 accomplish a one-to-one correspondence between
7 reductions and emissions and levels of methylmercury
8 fish tissue?
9
THE WITNESS: I can't speak to the exact
10 wording of the rule. That's something I looked at and
11 my eyes glazed over. Sorry. But basically my
12 assumption in all of this was that what the State of
13 Illinois wanted was to reduce the amount of
14 methylmercury in fish. From Marcia Willhite's testimony
15 and other sources it seemed, at least initially, that
16 they were looking to a one-to-one relationship; that if
17 you reduced, as I've said repeatedly, by -- say a factor
18 of "X" the amount of emissions from a coal-fired power
19 plant, the same reduction of "X" methylmercury in fish.
20 And I continue to repeat that that's not something that
21 will occur.
22
MR. HARLEY: Dr. Chapman, setting aside the
23 issue of one-to-one reduction, to clarify the record, it
24 is your testimony that CAMR/CAIR 2010 reductions plus
30
1 the reduction that would be added on by the Illinois
2 rule would, in your opinion, lead to some reductions in
3 methylmercury levels in fish tissue?
4
THE WITNESS: And just to clarify, what
5 you're talking is the U.S. EPA plus the additional from
6 IEPA? There would be some reduction. How much I can't
7 say.
8
MR. HARLEY: Thank you, Doctor.
9
HEARING OFFICER TIPSORD: Question No. 6.
10
THE WITNESS: What is the basis of your
11 opinion as stated on Page 7 of your testimony that,
12 "other local sources of mercury will have inputs to
13 different waterbodies that likely are, in some cases,
14 greater than these from coal-fired power plants"?
15
Answer: As noted in my answer to
16 Question 2, there can be a variety of other sources of
17 mercury to waterbodies. In come cases mercury from
18 these sources to those waterbodies will be greater than
19 that coming from atmosphere sources including, but not
20 restricted to, coal-fired power plants. For example, I
21 personally experienced with contaminated site
22 assessments where elevated levels of mercury in
23 waterbodies were primarily related other inputs than
24 atmospheric.
31
1
MR. KIM: Couple of questions: First of
2 all, when you state -- make reference to other local
3 sources of mercury, what are you specifically referring
4 to?
5
THE WITNESS: Other sources of -- I'm sorry.
6 Atmospheric or local sources.
7
MR. KIM: Just the reference that you have
8 in your testimony. I believe the quoted portion from
9 the question states other local sources of mercury will
10 have inputs to other waterbodies.
11
THE WITNESS: Basically it depends what's
12 there. If you have alkaline plant there you'll have
13 mercury coming out. Mills have a lot of mercury. If
14 you've got, as I mentioned before, pharmaceuticals,
15 disposal of substance containing mercury, hospitals,
16 dentists, you know, major source of mercury from the
17 amalgamum and so on. Atmospheric deposition can come
18 from other areas as well. But, you know, locally you
19 can have some very big differences, and the sources can
20 overwhelm anything that comes in from the atmosphere for
21 any source. And we've seen that repeatedly in
22 contaminated sites assessments and other similar
23 assessments.
24
MR. KIM: And if it's all right with the
32
1 hearing officer, Dr. Hornshaw has a follow-up question
2 that I won't do justice to.
3
DR. HORNSHAW: We have of what we call
4 special mercury advisory for waterbodies that are
5 significantly worse than the rest of the bodies of the
6 state where we have a state-wide advisory. The
7 state-wide advisory cautions women of childbearing age
8 and children under 15 to eat no more than one meal per
9 week of any predator species, and then the special
10 mercury advice is more restricted than that; for women
11 of childbearing age and children usually a
12 recommendation to eat no more than one meal per month.
13 And we also have recommendations for the general
14 population as well. We have 14 bodies of water and one
15 entire river system on a special mercury advisory. So I
16 was wondering, in these waters where we already know
17 conversion of methylmercury is substantial, what would
18 you expect as a percent reduction in those waters from
19 the reductions that we're talking about from the CAMR
20 rule and -- the CAMR rule plus the Illinois rule.
21
MR. BONEBRAKE: Just for clarification we've
22 been asking some questions about the impact in the
23 aggregate of CAMR and the Illinois rule. And when these
24 questions had been presented, I had been assuming that
33
1 they're asking for the aggregate impact of CAMR
2 reductions across the nation and not just Illinois. Is
3 that the predicate for your question, Dr. Hornshaw?
4
DR. HORNSHAW: Yes. But directed towards
5 specific waterbodies rather than the entire state where
6 we already know we have a problem.
7
THE WITNESS: Okay. I cannot say because,
8 first of all, I don't know exactly where those
9 waterbodies are in relation to other -- to potential
10 sources of different types. So I don't know the
11 relative importance. It's so hypothetical it's -- I
12 can't really say, I'm afraid.
13
MR. KIM: Dr. Hornshaw, to, I guess, set up
14 his question to you, repeated information that had been,
15 you're lucky you weren't here for the entire, that he
16 had previously provided either through oral testimony or
17 through prefiled testimony. I guess were you, in the
18 course of preparing for the hearing today, were you
19 familiar with the background facts and the different
20 advisory levels that he just described in his preface to
21 his question to you?
22
THE WITNESS: I've looked at the different
23 advisory levels, but I haven't looked in detail at each
24 of the sites in which they apply.
34
1
HEARING OFFICER TIPSORD: Question No. 7.
2
THE WITNESS: Question 7: In your
3 professional opinion, what are the most important
4 factors to mercury bioaccumulation in fish tissue and
5 how would you recommend those factors be controlled in
6 order to reduce mercury levels in fish tissue?
7
Answer: There are many factors that
8 affect mercury bioaccumulation in fish including a
9 source of biodegradable inorganic mercury and proceeding
10 through to production of methylmercury and it's uptake
11 by fish via their diet. Site specificity is critically
12 important related the conversion of inorganic mercury to
13 methylmercury. Reducing mercury levels in fish is best
14 accomplished by reducing the levels of methylmercury
15 that are available to them via their food in the
16 waterbodies they live in. Research on this issue is
17 continuing. For example, as stated in my written
18 testimony based on very recently published research,
19 quote, decreases in sulfate deposition alone with no
20 changes in mercury inputs could result in lower
21 methylmercury levels in fresh water fish, end quote.
22 Thus the apparently obvious approach to reduce mercury
23 levels in fish tissue, namely by reducing inputs of
24 inorganic mercury aquatic systems, may well not be the
35
1 best approach. At this point in time given the
2 advancing state of mercury research, it is not clear
3 what the best approach or combination of approaches is
4 and whether such are best-applied generically or site
5 specifically.
6
HEARING OFFICER TIPSORD: Mr. Kim?
7
MR. KIM: When would you imagine from a
8 scientific standpoint you would research or theories
9 would advance to the point that you would have a better
10 idea of what the best approach is.
11
THE WITNESS: Two comments: First of all,
12 we never have absolute certainty in science and we're
13 often blamed for saying we need more data. But you can
14 reach a reasonable level of certainty. The research I'm
15 quoting just came out a couple of months ago in a very
16 prestigious journal. It was quite exciting. There
17 seemed to be a number of breakthroughs occurring
18 nowadays that may lead us to have information sufficient
19 once you have, in this case of Illinois, a good
20 understanding where the sources are, what's coming and
21 what's happening, to make some decision in maybe a few
22 years, reasonable decision in maybe a few years. This
23 may well be possible.
24
MR. KIM: Do you understand, however, that
36
1 the Illinois -- that the State of Illinois acted within
2 the confines of the directives of the federal CAMR does
3 not have that period of time to act in a manner so that
4 the state could have its own plan, is that correct,
5 based upon your understanding?
6
MR. BONEBRAKE: I'm just going to object to
7 that to the extent that it calls for a legal conclusion.
8 But you can answer, Dr. Chapman.
9
THE WITNESS: I was going to answer. As I
10 said, the regulations and rules, you know, not my thing
11 at all by any means.
12
But just comment generally that I've had
13 a number of cases in my career where I've watched things
14 occur which seemed to be the obvious solution, and a lot
15 of time and money was expended on them and it turned out
16 to not be the obvious solution. A good example is in
17 Canada where we've done a lot of work with the pulp
18 mills, and the issue there was deformed fish, fish with
19 lesions and so on. And they went to various high levels
20 of treatment, but that did not obviate the problem.
21 They spent all this time and money and energy. And then
22 there was no time, money, and energy to dedicate what
23 turned out to be the real problems and address them. So
24 my personal concern, I speak personally now, not as a
37
1 scientist, is that we not rush into things, and maybe we
2 need to take the time to make sure we don't make the
3 mistakes and lose the opportunity to fully address the
4 issues that need to be addressed. My personal opinion.
5
MR. KIM: Do you believe that if a state
6 decides to engage in an initiative such as the Illinois
7 Mercury Rule, that it's the State's responsibility to
8 conduct that science and research before they go forward
9 with some kind of proposition?
10
THE WITNESS: I cannot speak as to whose
11 responsibility it is, but -- in a legal sense. But I
12 would think simply in a human sense that if you're going
13 to put something forward and it's going to make a heck
14 of a difference or you hope it's going make a heck of a
15 difference, you'd have enough research to be absolutely
16 sure that it was going to occur.
17
MR. KIM: Do you have any understanding or
18 any knowledge as to the resources available to the State
19 of Illinois to conduct the type of research and study
20 that you're referring to?
21
THE WITNESS: I do not.
22
MR. KIM: Do you have any idea how much --
23 You said you're referring to Canada, the studies
24 concerning pulp mills. Do you have any estimate as to
38
1 how much from a financial standpoint conducting those
2 types of studies or data collection, how much that would
3 cost?
4
THE WITNESS: I don't.
5
HEARING OFFICER TIPSORD: Dr. Chapman, I'm
6 kind of curious, because a couple of times you've talked
7 about the lack of data to support the Illinois rule as
8 far as to do a correlation between reducing the mercury
9 emissions and methylmercury in predator fish. Would you
10 agree then that that would be true also of the federal
11 rule? Because it seems to me a lot of the basis of
12 what's in Illinois is actually natural information. Do
13 you also believe that the CAMR rule may be premature
14 because of lack of data?
15
THE WITNESS: I can't say because I haven't
16 looked into that in any great detail. As I mentioned,
17 my areas of expertise are scientific. I tend to avoid
18 looking at rules, per se, unless I have a reason to do
19 so.
20
HEARING OFFICER TIPSORD: Mr. Harley?
21
MR. HARLEY: In answering the last question
22 and also in your prefiled testimony, you stress the
23 potentially important rule of sulfates in waterbodies
24 and producing methylmercury created conditions; is that
39
1 correct?
2
THE WITNESS: Yes.
3
MR. HARLEY: Do the emissions of coal-fired
4 power plants also contribute sulfates, sulphate
5 deposition into waterbodies?
6
THE WITNESS: I'm not sure.
7
MR. HARLEY: Another question I'd like to
8 ask you is also related to the prefiled testimony in the
9 way that you've framed the question that you then
10 answered in your testimony under Question 2. In light
11 of your concerns about levels of certainty, in
12 Question 2 you pose the question will reducing inorganic
13 mercury emissions from coal-fired power plants in
14 Illinois under the proposed rule ensure that impairment
15 restrictions can be lifted. Would you please comment on
16 what level of certainty is attached to the word ensure
17 in the way you characterized your question to yourself.
18
MR. BONEBRAKE: Just for clarification,
19 you're referring to Question No. 2 on Page 2 of his
20 testimony.
21
MR. HARLEY: Thank you, Mr. Bonebrake. I
22 am.
23
THE WITNESS: Basically I'm looking for not
24 100 percent certainty because, as mentioned, we never
40
1 get that in science, but a reasonable level of
2 certainty. And one of the issues related to Question 2
3 is that the mercury is not the only factor causing
4 impairment. We also have PCBs which are not addressed
5 by the proposed rule.
6
MR. HARLEY: And also later your question
7 can be lifted for waterbodies. Did you mean for all
8 waterbodies or any waterbody, especially in light of the
9 high variability in waterbody conditions?
10
THE WITNESS: I'm talking about waterbodies
11 generically across the state of Illinois.
12
MR. HARLEY: Is it possible that
13 restrictions could be lifted for some and not others?
14
THE WITNESS: I would not be surprised if
15 that were the case. You know, if you had substantial
16 reductions in mercury inputs from all sorts of sources,
17 it's still -- in some cases you will have mercury, as I
18 mentioned, in the deeper sediments that will still be
19 cycled through and forming methylmercury, and it'll vary
20 site specifically. So I would not expect total
21 uniformity. I'm talking generically.
22
MR. HARLEY: And when you talk about the
23 proposed rule in the way that you phrase Question 2 to
24 yourself, when you say the proposed rule, did you mean
41
1 CAMR/CAIR 2010 plus the Illinois rule?
2
THE WITNESS: I was talking about the
3 Illinois rule.
4
MR. HARLEY: The reductions that would be
5 achieved through the Illinois rule alone.
6
THE WITNESS: By the Illinois rule over and
7 above CAMR.
8
HEARING OFFICER TIPSORD: Mr. Rao?
9
MR. RAO: Dr. Chapman, on Page 10 of your
10 testimony, actually it was referenced to in Question
11 No. 10, you state that there is no consistent
12 relationship between total mercury concentrations in
13 sediments and mercury concentrations, primarily metal
14 mercury, in fish tissues of impaired waters. Are you
15 aware of any peer review studies dealing with the
16 relationship between total mercury concentration in
17 sediments and mercury concentration in fish tissues?
18
THE WITNESS: There have been a number of
19 studies that have looked at the total mercury
20 concentrations in sediments, but realize it's inorganic
21 and methylmercury combined. Ideally what you want to do
22 is measure the methylmercury concentrations in
23 sediments. I've been involved in a number of these
24 where you look at the methylmercury concentrations in
42
1 sediments. You look at them in the creatures eating the
2 sediments, and then you try to relate it back to fish.
3 And if you're looking at it in terms of methylmercury,
4 then you can draw up some reasonable conclusions. But
5 in terms of total mercury which includes inorganic and
6 organic, there's nothing that's really reached
7 reasonable conclusions in the literature that I'm aware
8 of.
9
MR. RAO: So it would make more sense to
10 analyze the relationship between methylmercury rather
11 than total mercury?
12
THE WITNESS: Yes. Because that's what
13 you're concerned about. And as Marcia Willhite said and
14 pointed out in her testimony, the concentrations, well
15 to proportion of methylmercury in sediments compared to
16 total mercury can be quite variable in different
17 sediments, in different circumstances. What you're
18 concerned about is not the inorganic mercury. Inorganic
19 mercury effects will be acute, and you have to have very
20 high concentration to have an acute effect. They do not
21 biomagnify. They do not move through the food chain.
22 And inorganic substances are taken out by organisms
23 through a very different process of passive diffusion
24 rather than accumulation through the lipid, through the
43
1 fat, which the methylmercury has. It's a totally
2 different ball game, so to speak. I could go on, but I
3 won't bore you.
4
MR. RAO: Thank you.
5
HEARING OFFICER TIPSORD: Mr. Kim?
6
MR. KIM: Just to back up a little bit.
7 Where Mr. Harley was asking you a question about
8 different advisories, is it your understanding that in
9 Illinois we may have waterways that have advisories that
10 would be specific as to mercury, and we may have other
11 advisories that may be based upon combination of mercury
12 and PCB levels?
13
THE WITNESS: I believe there are
14 waterbodies where mercury is the major issue, possibly
15 the only issue, and others where it's mercury and PCBs.
16 But, again, I haven't looked into that extensively.
17
MR. KIM: As to the waterbodies that may
18 have a mercury-only designation in terms of being
19 identified in the advisory, is it possible then that if
20 mercury emissions were limited in the matter that's
21 being proposed by the Illinois rule, that some or a
22 number of those waterways may be able to have that
23 mercury-only advisory lifted?
24
THE WITNESS: Can you clarify? Are you
44
1 talking about the CAMR plus the rule, or are you talking
2 only about the rule?
3
MR. KIM: Well, I guess -- and I'm just sort
4 of following up on your testimony. I'm -- And maybe
5 this is just a little problem I'm having in my head.
6 But obviously under -- and I'm not trying to testify,
7 but my understanding is under the federal scheme, CAMR
8 will be in place for any state that does not decide to
9 adopt its own rule. So I guess when people are saying
10 CAMR plus Illinois or Illinois alone, I'm having, in my
11 mind, a hard time distinguishing -- I'm speaking in
12 terms of the Illinois rule while not attempting to take
13 a blind eye to the fact that whatever states decide to
14 vote on CAMR go and vote on CAMR. So in my mind I'm not
15 sure how to make that distinction when people are
16 saying, well, Illinois rule plus CAMR or just the
17 Illinois rule. I'll let you try to make that
18 distinction if you want to try.
19
MR. BONEBRAKE: Just a point of
20 clarification, if I will, Mr. Kim. One of the
21 conceptual differences is CAMR is a rule of national
22 applicability, so it may create emission reductions in
23 other states. And we've had a lot of testimony in this
24 proceeding regarding transport of mercury. So I think
45
1 there probably, and I'm not going to testify either, but
2 there are potential differences in an Illinois-rule-only
3 scenario versus Illinois rule plus the impact of rules
4 adopted in other states. And I guess that was the point
5 of distinction that I was trying to raise earlier in my
6 clarification that I had raised and I think you're now
7 addressing.
8
HEARING OFFICER TIPSORD: If I may, if I
9 may. I think we established earlier with Dr. Chapman
10 that what the modeling approach that he looked at from
11 Krish's testimony was the CAMR rule implementation
12 versus CAMR rule plus Illinois. And so I think that
13 when we're asking these questions, we are looking to
14 what you looked at, Dr. Chapman, and based on what you
15 looked at using Krish's modeling. Am I adequately
16 addressing that?
17
MR. KIM: That's fair.
18
HEARING OFFICER TIPSORD: So I think when
19 we're all asking these questions, we're all asking you
20 to use the modeling data you used in forming the basis
21 of your testimony and asking questions that further
22 clarify that.
23
THE WITNESS: Just to clarify, Madam Chair.
24 So unless it's specifically stated otherwise, I will
46
1 assume despite the wording of the question that what
2 they're talking about is the 4 percent difference in
3 deposition that Krish talked about. Is that okay?
4
HEARING OFFICER TIPSORD: That's fine.
5
THE WITNESS: I do need the question again
6 because I've lost it at this point. You might want to
7 rephrase that. I'm not sure.
8
MR. KIM: I'm trying to backtrack in my head
9 to find out what the question was. I think the question
10 was would you expect, I'm going to speak generically,
11 under the Illinois rule with the understanding that the
12 hearing officer has just provided, that it is possible
13 that some of the waterways in the State of Illinois that
14 have been identified under a mercury-only advisory would
15 be able to have -- would be able to have that advisory
16 lifted as a result of the implementation of the Illinois
17 rule?
18
THE WITNESS: It's possible. Anything is
19 possible. Given there's only a 4 percent difference in
20 deposition between CAMR and the rule, you'd have to be
21 awful close to the level in terms of methylmercury in
22 fish and you'd have to have a waterbody that was really
23 just a tipping point for that to occur. So it's
24 possible, but would it occur in a lot of areas? No. As
47
1 I've stated before, I'm not looking for -- I don't
2 believe in my professional opinion that 4 percent
3 deposition difference will result in a measurable
4 across-the-state difference in the methylmercury fish,
5 but variations do occur in waterbodies.
6
HEARING OFFICER TIPSORD: Question No. 8.
7
THE WITNESS: In Section 4.0 of your
8 testimony on Pages 9 and 10 you state that, "The
9 relationship between the power plant mercury emissions
10 and mercury in fish in Illinois can be assessed using
11 two key pieces of information: Sediment mercury data
12 and fish tissue mercury data." You further state,
13 "there is no consistent relationship between total
14 mercury concentrations in sediments and mercury
15 concentrations in fish tissues of impaired waters." How
16 would you explain the very wide-spread occurrence of
17 elevated mercury fish tissue levels; i.e., two-thirds of
18 the Illinois waterbodies have been tested?
19
Answer: My statement was that, quote,
20 "there is no consistent relationship between total
21 mercury concentrations and sediments and mercury
22 concentrations in fish tissues," end quote. I was
23 addressing the fact that it's not a one-to-one; i.e., a
24 linear relationship. It is clear from the data that
48
1 fish in Illinois have accumulated tissues. Their
2 widespread occurrence is likely a result of numerous
3 types of mercury inputs in the aquatic environment as
4 addressed in Question 2, coupled with conditions
5 appropriate for methylmercury production and its
6 assimilation into the food chain.
7
HEARING OFFICER TIPSORD: Question No. 9.
8
THE WITNESS: Question 9: On pages 10 and
9 11 of your testimony you state that, "[coal-fired power
10 plant] emissions cannot be directly related to mercury
11 concentrations in fish collected from nearby waters."
12 Why not?
13
For two reasons: First, because there
14 are other courses of mercury to waterbodies; and,
15 second, because as detailed in my testimony, emissions
16 are of inorganic mercury while mercury in fish is
17 largely organic mercury. I previously noted in my
18 written testimony the complexity of the relationship
19 between inorganic mercury in waterbodies and organic
20 mercury in fish in those waterbodies.
21
HEARING OFFICER TIPSORD: Question No. 10.
22
THE WITNESS: Question 10: On Page 11 of
23 your testimony, you state that "Illinois' proposed rule
24 would only result in a 4 percent reduction in deposition
49
1 in Illinois from Illinois coal-fired power plant
2 emissions compared to CAMR." What percent reduction in
3 deposition would occur under CAMR from units that buy
4 credits to comply rather than control?
5
I have no idea. This isn't my area of
6 expertise. As noted in my written testimony and
7 previously in my verbal testimony, I relied on
8 Dr. Vikayaraghavan's testimony for the 4 percent value.
9
HEARING OFFICER TIPSORD: Question No. 11.
10
THE WITNESS: No. 11. By your answer to
11 the second question you pose in your testimony, are you
12 recommending that Illinois not aggressively address the
13 26 percent of waters currently listed as impaired only
14 for mercury?
15
Answer: I am making no policy
16 recommendations. My written and present testimony deal
17 only with scientific realities.
18
HEARING OFFICER TIPSORD: Question 12.
19
THE WITNESS: Question 12: The Illinois
20 EPA's technical support document (TSD) states that the
21 average mercury concentration of 397 largemouth bass
22 samples collected between 1985-2004 is 0.17 or 0.19
23 milligram per kilogram, depending on how non-detects are
24 treated (TSD, Pages 62-63.) Further, Dr. Hornshaw
50
1 submitted tables showing that approximately two-thirds
2 to three-quarters of all waters with fish sampled for
3 mercury between 1998-2001 had predator species that
4 would require a consumption advisory. Give this
5 information, would you agree that more than 26 percent
6 of the state's waters might be impaired due to mercury?
7
The answer: I would agree there are a
8 number of waterbodies in Illinois that have fish with
9 mercury concentrations above consumption advisory level.
10 Exactly what percentage of the state's waters is
11 currently involved, I cannot say given that
12 Dr. Hornshaw's data series stops at 2001, and given that
13 the state has not sampled all the waters in Illinois.
14 Designation of impairment is a decision and that is not
15 my area of expertise.
16
MR. KIM: When you reviewed the technical
17 support document and Dr. Hornshaw's testimony, and this
18 sort of falls into something that Dr. Hornshaw asked you
19 previously, do you have an understanding as to the
20 method by which Illinois conducts fish sampling, and
21 specifically how it conducts the process that it follows
22 to conduct mercury sampling in fish tissue?
23
THE WITNESS: I read it. Candidly, I've
24 been holidays for over a week, and I can't recall it at
51
1 this point.
2
MR. KIM: Do you recall in your review of
3 the testimony or the transcripts reference to a program
4 entitled the Illinois Fish Contaminant Monitoring
5 Program?
6
THE WITNESS: I recall reading about and
7 seeing that program mentioned, yes.
8
MR. KIM: Maybe just to jog your memory, I'm
9 going to -- I'd like to ask you just some basic leading
10 questions concerning the program just to sort of see if
11 you can pick it up where it is I'm trying to go here.
12
Do you recall that under that program,
13 which I will go by the acronym FCMP, that there's a
14 criteria or there's a policy, rather, that two or more
15 samples that exceed a criterion for fish tissue are
16 necessary for issuing or changing an advisory?
17
THE WITNESS: I don't recall.
18
MR. KIM: Do you recall or do you have any
19 recollection based upon your review of that program any
20 inherent limitations concerning the number of fish that
21 would be sampled through an implementation of that
22 program?
23
THE WITNESS: To answer that question
24 correctly, I'd have to go back and look through it and
52
1 provide you with a full answer. I'd be very reluctant
2 to do so based on my limited recollection having read
3 that a couple of months ago.
4
MR. KIM: Okay. If your review of your --
5 that information resulted in your conclusion that it is
6 very possible that more Illinois waterways are impaired
7 due to mercury but have not been specifically identified
8 under the FCMP, would that change your testimony in any
9 way?
10
THE WITNESS: That's a hypothetical
11 question, but it wouldn't change my testimony in any way
12 because the bottom line for my testimony is simply that
13 there's this big disconnect between the amount of
14 inorganic mercury coming from coal-fired power plants
15 and the assumption that there's a linear reduction in
16 the amount of methylmercury in fish in waterbodies.
17
MR. KIM: Okay.
18
HEARING OFFICER TIPSORD: Question No. 13.
19
THE WITNESS: Would the information
20 presented above change your answer to your second
21 question regarding lifting impairment listings for
22 mercury?
23
Answer: No, it would not. As I noted
24 in my written testimony and as Marcia Willhite's verbal
53
1 testimony confirms, the amount of methylmercury in fish
2 is site specific and is not related simply to the amount
3 of inorganic mercury that's deposited to waterbody.
4
HEARING OFFICER TIPSORD: Question 14.
5
THE WITNESS: In Table 2 of your testimony
6 there are several entries in which two fish mercury
7 samples having the same concentration are paired with
8 two different sediment mercury values; e.g., lines 3 and
9 4 for the 1988 Jackson County samples. Do the two
10 sediment values represent the averages for the 2.5 years
11 before and after the 1988 fish sample or something else?
12 Are the two fish values of 0.167 milligram per kilogram
13 for a single sample, two samples, or all samples
14 collected from Jackson County in 1988?
15
Answer: The duplicate samples reflect
16 multiple sites within the same county for which
17 different fish samples with the same value were
18 collected but different sediment values. Specifically
19 for the samples with 0.167 milligram per kilogram of
20 mercury there were two sites with different GPS
21 coordinates that both show the fish tissue concentration
22 but the sediment mercury concentrations of those sites
23 different. The other duplicates were also due to
24 multiple sites with identical averages.
54
1
HEARING OFFICER TIPSORD: Question 15.
2
THE WITNESS: There are two 1990 Cook County
3 samples in Table 2 having a fish mercury concentration
4 of 0.47 milligram per kilogram and sediment values of
5 0.061 and 0.1 milligram per kilogram, and there's a 1990
6 Cook County fish sample in Table 3 also having a mercury
7 concentration of 0.47 milligram per kilogram but with a
8 sediment mercury value of 0.074 milligrams per kilogram.
9 If this is the same fish mercury sample, please explain
10 the discrepancy between the list of sediment mercury
11 values.
12
Answer: My apologies. This
13 discrepancy is due to an averaging error that occurred.
14 When the calculations were being done for Table 2, one
15 value was inadvertently excluded from the average. The
16 fish tissue value is correct at 0.47 milligram per
17 kilogram, but the sediment value should be 0.074
18 milligram per kilogram as in Table 3, not 0.061
19 milligram per kilogram. They should be one value for
20 1990 with fish tissue at 0.47 and sediments at 0.074. I
21 apologize for this error, but note that it has no
22 material effect on my written testimony.
23
MR. BONEBRAKE: Prairie questions.
24
THE WITNESS: Question one: Do you expect
55
1 that a 90 percent reduction mercury emissions from
2 Illinois power plants will result in similar reduction
3 of methylmercury concentrations in fish in Illinois? If
4 not, why not?
5
Answer: No, I do not. Because, as
6 explained in my written testimony, the relationship
7 between deposition of inorganic mercury from power
8 plants and other sources and accumulation of organic
9 mercury in fish is complex, site specific, and very
10 highly unlikely to be linear.
11
HEARING OFFICER TIPSORD: Question 2.
12
THE WITNESS: Do you believe there is a
13 linear relationship between mercury reductions in power
14 plant emissions and mercury reductions in fish tissue?
15
Answer: I do not.
16
HEARING OFFICER TIPSORD: Question 3.
17
THE WITNESS: Do you believe that a 90
18 percent reduction in mercury emissions from coal-fired
19 power plants in Illinois will cause a water restriction
20 for mercury to be lifted in Illinois? If not, why not?
21
Answer: No, I do not for two reasons which
22 are fully -- which are explained more fully in my
23 written testimony. First and foremost, coal-fired power
24 plants in Illinois are not the only sources of inorganic
56
1 mercury to Illinois waters. Some reduction in mercury
2 in Illinois waters would be expected due to reductions
3 in mercury emissions. But such reduction is not
4 expected to be immediate or to have a linear
5 relationship to any reduction in air emissions as
6 previously stated in my testimony.
7
Second, it would be difficult to
8 predict the level of reduction in the aquatic
9 environment and time frame for any such reduction due to
10 the fact that mercury is an element and does not
11 biodegrade with the tide. So reducing one of the
12 sources cannot be expected to reduce levels already in
13 the aquatic system. Mercury impairment, TMDL
14 classifications for Illinois waterbodies are a
15 reflection of numerous inputs to the environment natural
16 and manmade over a long period of time. Reducing one
17 input that is not directly related to the total
18 concentrations already in the waterbodies will not, in
19 my opinion, result in the lifting of mercury TMDL fish
20 consumption restrictions.
21
HEARING OFFICER TIPSORD: For the record,
22 those last three questions are from Prairie State
23 Generating Company. Is there anything else for
24 Dr. Chapman?
57
1
MR. BONEBRAKE: If I may have just a moment.
2 No further questions on our end.
3
HEARING OFFICER TIPSORD: Anything else?
4
MR. KIM: No. We hope Dr. Chapman gets to
5 enjoy the rest of his holiday.
6
HEARING OFFICER TIPSORD: Dr. Chapman, thank
7 you very much. We appreciate your taking the time to be
8 with us.
9
THE WITNESS: Thank you.
10
HEARING OFFICER TIPSORD: We'll take a
11 ten-minute break.
12
(Short break taken.)
13
MR. BONEBRAKE: Madam Hearing Officer, I
14 would tender the written testimony of Dr. Gail Charnley.
15
HEARING OFFICER TIPSORD: We will enter this
16 as Exhibit 130. Seeing no objection, this is Exhibit
17 No. 130.
18
MR. BONEBRAKE: I think Miss Charnley had a
19 short introduction and then she was going to turn first
20 to the questions of IEPA.
21
THE WITNESS: As advertised, I'm Gail
22 Charnley, and I am a toxicologist. I have a Ph.D. in
23 toxicology from MIT. I've spent the last 30 years
24 studying the relationships between chemical exposures
58
1 and adverse health effects. I'm a risk analyst. I have
2 been the director of the Toxicology and Risk Program at
3 the National Academy of Sciences. I've been the
4 executive director of the Presidential Congressional
5 Commission on Risk Assessment and Risk Management. I've
6 been the president of the International Society For Risk
7 Analysis. And I now work part-time on a consulting
8 basis.
9
So as to the questions. No. 1: Prior to
10 this rule-making, have you ever provided expert
11 testimony on the relationship between power plant
12 mercury emissions and fish methylmercury concentrations?
13
Yes. I provided expert testimony to the
14 Pennsylvania State Senate Environmental Resources and
15 Energy Committee on June 6, 2006; to the Idaho House
16 Environment Energy and Technology Committee on March 2,
17 2006, and to the Montana Governor's Board of
18 Environmental Review in September of 2005. I had an
19 informal conversation about that subject with Illinois
20 legislators on March 16, 2006, and I've been invited to
21 make a presentation to the Pennsylvania House
22 Environment Resources and Energy Committee in September.
23
1B: Have you ever conducted and
24 published any scientific research on the relationship
59
1 between power plant mercury emissions and fish
2 methylmercury concentrations?
3
Answer: I no longer conduct laboratory
4 research. I have published two articles on power plant
5 mercury emissions and fish methylmercury concentrations.
6 The American Council on Science and Health published a
7 report on power plant mercury emissions and fish
8 methylmercury concentrations using some of the
9 information from one of my articles.
10
1C: Have you ever conducted and
11 published any scientific research on the toxicology of
12 methylmercury?
13
Answer: I have a Ph.D. in toxicology
14 from MIT. I have published two articles on the
15 toxicology of methylmercury. I have studied the
16 relationship between chemical exposures and public
17 health for over 30 years.
18
1G: Have you ever conducted an
19 environmental health risk analysis of power plant
20 emissions for any of the coal-fired power plants in
21 Illinois?
22
Answer: Not in Illinois, no.
23
1E: Were you asked by the National
24 Research Council/national Academy of Sciences to provide
60
1 an independent review of any draft versions of the
2 report entitled Toxicological Effects of Methylmercury
3 (2000)?
4
Answer: No. I was employed by the
5 Academy during part of the time that that committee
6 deliberated, so it would have been considered a
7 conflict.
8
Question No. 2: How do you reconcile
9 the statement in your testimony on Page 2 that "About
10 half of global mercury emissions are naturally
11 occurring" with the cited source for this information
12 (see footnote No. 1) which indicates, both in text and
13 in a pie-chart, that only one-third of mercury emissions
14 are naturally occurring?
15
Answer: The cited source also says that
16 its estimates of emissions are highly uncertain. I
17 should also have included Pacyna, et al., P-A-C-Y-N-A,
18 et al, 2003, Friedli, et al., F-R-I-E-D-L-I, 2003, and
19 Pyle, P-Y-L-E, and Mather, M-A-T-H-E-R, 2003, as
20 sources. Based on those sources about 55 percent of
21 global emissions can be attributed to natural sources.
22 That estimate is higher than EPA's -- USEPA's because of
23 higher estimates for mercury emissions from volcanoes
24 and forest fires. My statement that, "about half" of
61
1 emissions are naturally occurring lies somewhere between
2 the two estimates and is intended to reflect their
3 inherent uncertainty.
4
Question 3: Do you dispute that the
5 National Research Council's Committee on the
6 Toxicological Effects of Methylmercury produced a
7 recommendation on the reference dose for methylmercury
8 exposure that supported USEPA's numerical value of 0.1
9 micrograms per kilogram per day?
10
Answer: The Academy Committee produced
11 an RFD recommendation, yes, but the suggested RFD does
12 not fully support the USEPA position. USEPA developed
13 its current reference dose with an uncertainty factor of
14 10 for within human variability and a one-fold factor
15 for data base gaps. In contrast, the NAS panel
16 suggested an uncertainty factor of three-fold for human
17 variability with an additional three-fold for data base
18 gaps (both of these factors, when put together, result
19 in a ten-fold factor). Although the total factor is the
20 same in both cases, the reasons for the factors are
21 different.
22
MR. BONEBRAKE: Just for clarification,
23 Dr. Charnley, your shorthand RFD, is that short for
24 reference dose?
62
1
THE WITNESS: RFD is shorthand for reference
2 dose.
3
HEARING OFFICER TIPSORD: Mr. Harley?
4
MR. HARLEY: Good morning, Dr. Charnley. My
5 name is Keith Harley. I'm an attorney representing a
6 group called Environment Illinois.
7
Dr. Charnley, are there any potential
8 benefits at all that can be achieved by regulating
9 mercury emissions from coal-fired power plants?
10
THE WITNESS: I should think so, but I'll
11 get to that when we talk about benefits. I was going to
12 go through my questions here. Is there something -- Is
13 there a question you had related to the National Academy
14 of Sciences report?
15
MR. HARLEY: I'm referring to the first part
16 of your testimony in which you question many of the
17 assumptions which would underlie both the federal rule
18 and both the Illinois rule in terms of the benefits
19 being achieved by regulating mercury emission from
20 coal-fire power plants. I'm just wondering in light of
21 those fundamental questions you have about the value of
22 regulating those emissions, do you see that there is any
23 benefit whatsoever to be achieved by regulating these
24 emissions?
63
1
MR. BONEBRAKE: Just so it's clear, you mean
2 any regulation, or are you referring, Mr. Harley,
3 specifically to the Illinois rule?
4
MR. HARLEY: Any regulation whatsoever.
5
THE WITNESS: I think reducing methylmercury
6 emissions from power plants and other sources is a good
7 idea in general, yes, and I'll be talking about this
8 much more specifically as we go along.
9
MR. HARLEY: Just one follow-up quickly.
10 From power plant specifically?
11
THE WITNESS: Yes.
12
MR. HARLEY: Thank you.
13
HEARING OFFICER TIPSORD: Question No. 4.
14
THE WITNESS: On Page 4, you state that
15 "Figure 24 in the Florida report shows clearly that
16 between 1994 and 2000, the time period of interest,
17 there was no decline in deposition." Do you disagree
18 with the assertion that the plot shows a general decline
19 from 1994-1999, as well as an overall decline for the
20 longer time period of 1994-2002?
21
HEARING OFFICER TIPSORD: Excuse me,
22 Dr. Charnley. Before you answer that, just for purposes
23 of the record, the Florida report referenced there is
24 the Florida report that is in the Board's record. It's
64
1 the integrating atmospheric mercury deposition with
2 aquatic cycling from South Florida from the Florida
3 Department of Environmental Protection.
4
THE WITNESS: Thank you.
5
Answer: I don't disagree with that
6 assertion. What I dispute is the relevance of the
7 statement on Page 78 of the Florida report that
8 deposition of mercury at one site declined by 25 percent
9 between 1994 and 2002. That is the statement used to
10 support a relationship between emissions, deposition,
11 and fish. The problem is the fact that the TSD includes
12 fish data from Florida that support its position and
13 excludes fish data that do not.
14
HEARING OFFICER TIPSORD: Question No. 5?
15
THE WITNESS: In regard to the Florida and
16 Massachusetts studies, do you contend that the results
17 are scientifically invalid because they weren't
18 published in a peer-reviewed journal (see Page 6)?
19
Answer: In my testimony on Pages 4 and
20 6, I merely state that those studies have not been
21 peer-reviewed or published in peer-reviewed scientific
22 journals. Publication is not related to scientific
23 validity. The results may be valid. The way Illinois
24 EPA is using them is not.
65
1
MR. MATOESIAN: Could you explain what you
2 mean by not valid?
3
THE WITNESS: Well, the TSD only uses the
4 fish methylmercury data from two sites: From the
5 Florida report where, in fact, methylmercury levels did
6 decrease. But the study itself looked at 12 sites in
7 Florida, and in some of those sites methylmercury levels
8 didn't change, and in one of them they actually -- it
9 actually went up. So I thought that representing the
10 Florida study as showing methylmercury decreases given
11 that it did in some cases and it didn't in others didn't
12 convey the full weight of the scientific evidence.
13
HEARING OFFICER TIPSORD: Question No. 6.
14
THE WITNESS: You state that "reducing
15 mercury emissions should not be oversold as a means of
16 improving public health and protecting children in
17 general" (Page 8). How would you define an "oversold"
18 situation for Illinois?
19
Answer: The implication made in the TSD
20 is that reducing Illinois power plant mercury emissions
21 by 90 percent will reduce Illinois fish methylmercury
22 concentrations by 90 percent and that this will reduce
23 health risks for methylmercury. As most Illinois
24 residents, methylmercury exposure is unlikely to come
66
1 from Illinois fish, a reduction in health risk as a
2 general matter is unlikely. If there is a group of
3 people in Illinois who subsist on mercury contaminated
4 Illinois fish which the TSD has not clearly established
5 and conditions are such that reducing Illinois power
6 plant emissions does reduce fish methylmercury
7 concentrations in the particular fish consumed by that
8 particular group, a reduction in risk is certainly
9 possible for that group. Extrapolating from that
10 theoretical situation to Illinois residents in general
11 is what I mean by oversold.
12
For example, the August 6 edition of the
13 Chicago Tribune states, "Governor Rob Blagojevich
14 proposed some of the toughest mercury pollution controls
15 for utilities in the nation. He did so, he said, in
16 response to a frightening Tribune series on mercury
17 contamination in fish. The Tribune series to which he
18 referred was based on seafood for sale in Chicago area
19 stores, not on Illinois freshwater fish and subsistent
20 fishers. His proposed rule will have no impact on
21 methylmercury levels in seafood at the supermarket.
22
HEARING OFFICER TIPSORD: Mr. Harley?
23
MR. MATOESIAN: First, where in the TSD were
24 you referring to a direct 90 percent reduction equated
67
1 to a 90 percent mercury reduction?
2
THE WITNESS: Well, I note that first the
3 TSD establishes that in order to achieve the goal, which
4 I read as being making it possible for all women of
5 childbearing age and children in Illinois to eat as many
6 predator fish caught from Illinois waters as they chose,
7 that a 90 percent reduction in methylmercury
8 concentrations would be necessary. And then the TSD
9 goes on to say that the 90 percent reduction in
10 emissions is the goal of controlling the emissions. So
11 their juxtaposition led one to conclude, well, that
12 is -- by reducing emissions by 90 percent there seems to
13 be an implication anyway that that would lead to a 90
14 percent reduction in methylmercury concentrations in
15 predator fish.
16
MR. MATOESIAN: So it wasn't an actual
17 statement. It's an inference?
18
THE WITNESS: No, not as I recall. But the
19 way that they're juxtaposed and presented together
20 certainly implies that they're related.
21
MR. MATOESIAN: Are you aware that Illinois,
22 for instance, has a large menu of programs to reduce
23 mercury in the environment?
24
THE WITNESS: I'm not familiar with all of
68
1 Illinois's menu to reduce mercury in the environment,
2 no.
3
MR. MATOESIAN: And I can't remember if you
4 were at the June hearing in Springfield or not.
5
THE WITNESS: No.
6
MR. MATOESIAN: Where Dr. Keiler went over
7 deposition in great depth, and I believe his assumption
8 or his studies cited roughly a 70 percent reduction in
9 mercury.
10
THE WITNESS: In deposition.
11
MR. MATOESIAN: In deposition from local
12 power plants.
13
MR. BONEBRAKE: Are you presenting a
14 question, Mr. Matoesian?
15
MR. MATOESIAN: I was questioning whether
16 she was -- excuse me -- familiar with that testimony.
17
THE WITNESS: I read it, but I don't
18 remember. What I'm talking about is what's in the TSD.
19
MR. MATOESIAN: Now, would you agree that
20 the goal of public policy, though, should be to detect
21 as many people as possible if not everyone?
22
THE WITNESS: Of course.
23
MR. MATOESIAN: And then public policy,
24 certainly public health, should be based upon an
69
1 abundance of caution.
2
THE WITNESS: Reasoned abundance of caution,
3 yes.
4
MR. MATOESIAN: And you stated that the fish
5 at the supermarket which generally would not be
6 locally-caught fish, wouldn't be affected. I believe
7 that was in the Chicago Tribune article. But shouldn't
8 Illinois do what it can within its jurisdiction? I mean
9 you wouldn't expect us to regulate
10 internationally-caught fish, would you?
11
THE WITNESS: I wasn't implying that, no.
12
MR. MATOESIAN: Okay. But would you agree
13 that Illinois should at least try to take care of what
14 it can legally take care of?
15
THE WITNESS: Of course.
16
HEARING OFFICER TIPSORD: Mr. Harley?
17
MR. HARLEY: The language about the risk of
18 overselling, reductions in mercury emissions from
19 coal-fired power plants as a means to protect public
20 health and children in general is in the context of your
21 general concern about the lack of information about
22 people consuming fish in Illinois; is that correct?
23
THE WITNESS: That's part of it, yes.
24
MR. HARLEY: And you indicate on Page 7 of
70
1 your pretrial testimony that there's no information
2 available on the extent to which Illinois anglers
3 consume what they catch; is that correct?
4
THE WITNESS: That is what I gathered from
5 the TSD, yes.
6
MR. HARLEY: And there's no information --
7
THE WITNESS: In fact, it states as much, I
8 believe.
9
MR. HARLEY: There's no information about
10 the number of people who could be characterized as
11 subsistent anglers in Illinois; is that correct?
12
THE WITNESS: Correct.
13
MR. HARLEY: What's the definition of a
14 subsistence angler?
15
THE WITNESS: Well, I don't know what the
16 dictionary definition is. When I use that phrase I
17 think of people who catch and eat the local fish as
18 their primary and use it as their primary protein
19 source.
20
MR. HARLEY: Would one serving of fish,
21 predator fish caught in Illinois waters be subsistent
22 fishing?
23
THE WITNESS: One serving --
24
MR. HARLEY: Would consuming one serving of
71
1 fish per week caught in Illinois waters constitute
2 subsistent fishing?
3
THE WITNESS: I don't think of that as
4 subsistence fishing, but if there's a technical
5 definition, I'm not familiar with it.
6
MR. HARLEY: Then certainly once per month
7 would not constitute subsistence fishing, would it?
8
THE WITNESS: Correct.
9
MR. HARLEY: You're aware that there are
10 advisories in place in Illinois for all waterbodies
11 limit -- suggesting that people limit their fish
12 consumption to one serving per week of fish caught in
13 those waterbodies?
14
THE WITNESS: Yes.
15
MR. HARLEY: Do you agree with those
16 advisories?
17
THE WITNESS: I haven't performed an
18 analysis of that.
19
MR. HARLEY: Would you defer to people who
20 had performed a credible analysis?
21
THE WITNESS: Sure.
22
MR. HARLEY: Are you aware that there are
23 certain waterbodies in Illinois where there are even
24 more stringent and specific advisories that would limit
72
1 people to one serving per week?
2
THE WITNESS: I'm aware that there are, yes.
3
MR. HARLEY: That would not -- You would not
4 characterize that as being subsistent fishing, would
5 you?
6
THE WITNESS: Correct.
7
MR. HARLEY: Dr. Charnley, could you
8 describe for the Pollution Control Board your notion of
9 the Precautionary Principal in Toxicology and Public
10 Health?
11
THE WITNESS: The precautionary principal is
12 not part of toxicology. Precautionary principal is a
13 risk management strategy that relies on decisions that
14 are health protective when we're uncertain about risks.
15 But it does presuppose that we do know something about
16 risk.
17
MR. HARLEY: Do the fish advisories that
18 exist for Illinois waterways provide an adequate
19 characterization of risk of consuming fish from those
20 waterways in your opinion?
21
THE WITNESS: I don't know.
22
MR. HARLEY: In light of the fact that you
23 don't know, wouldn't the precautionary principal suggest
24 that we should resolve your uncertainty in such a way as
73
1 to protect the residents of Illinois rather than
2 endanger them?
3
THE WITNESS: From the way you've asked
4 that question, it sounds like I've said something about
5 how there shouldn't be fish advisories. I've never said
6 that.
7
MR. HARLEY: I'll withdraw the question.
8
HEARING OFFICER TIPSORD: Question No. 7.
9
THE WITNESS: You have largely focussed on
10 the results of the Seychelles Islands studies in your
11 discussion on methylmercury and developmental toxicity
12 and give limited to the discussion of the Faroes Islands
13 study and essentially none to the New Zealand study. Do
14 you dispute the findings (regarding
15 methylmercury-related development neurotoxicity) of the
16 New Zealand study as described in the TSD? Do you
17 disagree with Dr. Louise Ryan's evaluation of the
18 modeling results for the three epidemiological studies
19 (see technical Support Document, Appendix A, Pages
20 26-27).
21
Response: Yes. I dispute the findings
22 of the New Zealand study as described in the TSD. The
23 description of the findings of the New Zealand study in
24 the TSD is inaccurate reflecting the inaccurate summary
74
1 of the study in Appendix A. The TSD describes the
2 findings of the New Zealand study as follows: Quote, a
3 case control study was conducted in New Zealand of 74
4 children representing white, Maori, and Pacific Islander
5 ethnic groups. When tested at the age of 4, 52 percent
6 of this group had abnormal results when compared to 17
7 percent of the children in the control group.
8
Here is how a Harvard School of Public
9 Health report describes the findings of the same study.
10 From the 73 women with elevated hair mercury levels, 31
11 children were identified and administered tests of
12 neurologic development. Results were either
13 questionable or abnormal in 16 subjects, 52 percent,
14 compared to five subjects, 17 percent in the reference
15 group. The TSD thus misrepresents the number of
16 children involved in the study, describes results as
17 abnormal instead of questionable or abnormal and states
18 that more children were affected than actually were.
19 What I dispute about the TSD's portrayal of the Ryan
20 analysis is that it implies that IQ deficits were
21 observed, and this is the TSD's portrayal of the Ryan
22 analysis is that it implies that IQ deficits were
23 observed in the three epidemiologic studies. Neither
24 the New Zealand nor the Seychelles Island studies
75
1 reported a statistically significant IQ deficit. The
2 Faroes Islands study did not evaluate IQ, so an estimate
3 of an effect was made based on other studies. USEPA
4 points out that there is only limited evidence linking
5 IQ and methylmercury exposure. Using IQ as a surrogate
6 for other effects allowed USEPA to monetize potential
7 effects of methylmercury exposure for the purpose of
8 performing its regulatory impact analysis which it is
9 required to perform by the US Office of Management and
10 Budget. Furthermore, USEPA relies on an assumption
11 about the model it uses to monetize benefits that is
12 inconsistent with the way it evaluates methylmercury
13 risks. Because, as the USEPA puts it, it is technically
14 more simple and practical to do so. In other words, the
15 IQ model was chosen as a policy matter to simplify the
16 regulatory impact analysis. This is an example, I
17 believe, of the TSD's biased analysis; in other words,
18 failure to describe simplifying assumptions that are
19 based on policy, not science, and conveying the notion
20 that a statistical analysis used to monetize benefits
21 actually reflects a biological effect.
22
HEARING OFFICER TIPSORD: Question No. 8.
23
THE WITNESS: Has the Hibbeln, that's
24 H-I-B-B-E-L-N (2006) work received widespread acceptance
76
1 in the scientific community? Has it undergone
2 peer-reviewed publication?
3
Answer: The Hibbeln work has gone
4 through peer review and is in press in the Lancet, one
5 of the highest-quality medical journals in the world. I
6 include reference to it in my testimony because it is
7 consistent with some other studies suggesting that
8 eating fish during pregnancy can be beneficial. That
9 notion was not considered by the Illinois EPA.
10 Dr. Hibbeln has published quite a number of other
11 peer-reviewed studies on the neurodevelopmental benefits
12 of Omega-3 fatty acids, the components of fish believed
13 to contribute children's brain development.
14
Question 9: On Page 12, you state
15 that "it is my opinion and that of many other scientists
16 that the results of the Faroe Islands study at best
17 should be attributed to combined exposure to
18 methylmercury and PCBs." Is your opinion (and
19 presumably that of others) supported by data that you
20 have independently generated regarding breast milk PCB
21 concentrations in the Faroes Islands study (maternal)
22 participants? On what basis to you reject the position
23 expressed by the NRC's Committee on the Toxicological
24 Effects of Methylmercury in the 2000 NRC report?
77
1
Response: The NAS committee did not
2 completely rule out a potential real for PCB exposure in
3 the Faroes outcome because it listed PCBs as a source of
4 uncertainty in Table 8-2 of their report. In any case,
5 I have not rejected the Mercury Report Committee's
6 position because the Committee did not express a
7 position with regard to confounding by PCBs from breast
8 milk. The Committee evaluated only prenatal exposure to
9 PCBs, not postnatal exposure via breast milk, about
10 which publications were occurring at the time of the NAS
11 report. PCB exposure has been associated with poorer
12 performance on the Boston Naming Test which is the end
13 point upon which the NAS and USEPA methylmercury risk
14 assessments were based. According to a report by
15 Darsen, the level of postnatal PCB exposure in the
16 Faroes was 18 times higher than the level associated
17 with neurologic effects in the Lake Michigan studies.
18 PCBs have been associated with developmental
19 neurotoxicity in infant monkeys fed PCBs postnatally in
20 formula at a dose equivalent to about half that
21 experienced by the children in the Faroes.
22
In other words, the level of PCBs to
23 which the Faroese children were exposed via breast milk
24 was almost double the level demonstrated to produce
78
1 neurologic effects in infant monkeys, 18 times higher
2 than the levels associated with neurologic effect in
3 children near Lake Michigan, and 600 times higher than
4 USEPA's recommended exposure limit or reference dose for
5 PCBs. With any other similar exposure the USEPA would
6 very likely be taking immediate action to prevent
7 further exposure. The fact that the Faroe Islands
8 currently has a do not consume pilot whale blubber
9 advisory for pregnant women, the source of the majority
10 of the PCBs in mother's milk is consistent with this
11 being recognized as a serious health problem. A
12 comparison of PCB and methylmercury exposures in the
13 Faroes and Seychelles is depicted graphically in
14 Exhibit 3 of my testimony, and we have copies of that if
15 it's of interest; if not, if you remember it from my
16 testimony.
17
HEARING OFFICER TIPSORD: Actually, excuse
18 me, Dr. Charnley. If you have a color copy we'd like to
19 put that in as an exhibit because I think the testimony
20 has black and white, and since you went to all the
21 troubling to print them out.
22
We'll admit this as Exhibit No. 131.
23
THE WITNESS: So while I can't absolutely
24 prove that postnatal PCB exposure contributed to the
79
1 effects seen in the Faroese children, I consider it
2 impossible to conclude that they did not based on the
3 available toxicological information.
4
MR. MATOESIAN: Ma'am, did you do any
5 independently-generated work on this?
6
THE WITNESS: I took the -- Well, actually,
7 this is adapted from the 2001 paper by Darsen, et al.,
8 where he calculated intake of PCBs from breast milk
9 using the data from the Faroese investigators. I
10 checked his calculation independently and found my
11 answer was the same as his.
12
MR. MATOESIAN: Have you done any additional
13 independent research on this topic?
14
THE WITNESS: Myself, no.
15
MR. MATOESIAN: Okay. As PCBs tend to
16 accumulate in the fat tissue, correct?
17
THE WITNESS: Correct.
18
MR. MATOESIAN: Not in the muscle tissue.
19
THE WITNESS: Correct.
20
MR. MATOESIAN: So you wouldn't see it in
21 the pilot whale meat.
22
THE WITNESS: Not in the meat.
23
MR. MATOESIAN: Or in fish meat tissue. It
24 would be in the fatty tissue of fish, right?
80
1
THE WITNESS: Right.
2
MR. MATOESIAN: And mild caught fish can be
3 very lean and with fatty tissue would they not, or are
4 they not?
5
THE WITNESS: I'm not an expert in fish fat.
6
What these data show are the PCB levels
7 actually in the mother's milk. So they're reflecting
8 whatever they ate from whatever fish or pilot whale
9 source, so these are measurements.
10
Question 10: On Page 11 you write that,
11 "it is not surprising that where there were fewer
12 benefits from fish, the effects of methylmercury were
13 more likely to be manifests". Under what circumstances,
14 and for which particular studies, would you consider
15 there to be fewer benefits from eating fish?
16
Response: There were fewer benefits
17 from eating fish in the Faroe Islands compared to the
18 Seychelles because people in the Faroes didn't eat as
19 much fish as people in the Seychelles. In the Faroes,
20 more than half the mothers reported eating between zero
21 and two fishing meals per week with the remaining
22 mothers classified as eating more than two meals per
23 week. In the Seychelles, mothers ate an average of
24 twelve fish meals per week. In addition the pilot whale
81
1 blubber consumed in the Faroes is like to be rich in
2 Omega-6 fatty acids which compete at the cellular level
3 for the same sites as Omega-3 fatty acids, thereby
4 reducing the beneficial influence of the Omega-3 fatty
5 acids found in fish.
6
HEARING OFFICER TIPSORD: Question No. 11.
7
THE WITNESS: You write (on Page 12) that,
8 "the US Centers For Disease Control (CDC)reports that
9 children and women of childbearing age in the US have
10 methylmercury levels in their blood well below those
11 that have been reported to produce adverse effects". Do
12 you believe that this can be interpreted as a CDC claim
13 that there are no children and women of childbearing age
14 with methylmercury levels that have resulted in adverse
15 health effects?
16
Response: I believe that the statement
17 speaks for itself. And the representative sample of US
18 women tested, no one had blood mercury levels that have
19 been associated with adverse health effects. CDC states
20 that, "All women of childbearing age had levels below 58
21 micrograms per liter" which identifies as the
22 statistical lower limit on the dose associated with
23 effects on the Faroes. CDC also states, "blood mercury
24 levels in both the 1999-2000 and 2001-2002 subsamples
82
1 are below levels considered associated with known health
2 effects". And, "finding a measurable amount of mercury
3 in blood or urine does not mean that the level of
4 mercury causes an adverse health effect."
5
Question 12, do you agree that the, "5
6 percent likelihood of poorer performance on the Boston
7 Naming Test among children in the Faroe Islands" was
8 associated with 85 micrograms mercury per liter in
9 umbilical blood, not non-cord blood?
10
Response: I agree that that is what the
11 National Academy of Sciences Mercury Report Committee
12 calculated. However, this association does not
13 necessarily constitute a causal relationship, especially
14 because the Faroes' children had average exposures from
15 mother's milk to the neurotoxicant PCBs at doses that
16 were, on average, 600-fold above USEPA's reference dose.
17 The NAS did not look at PCB exposures from mother's
18 milk.
19
Thirteen: Do you contend that there is
20 no exposure level at which women whose exposures exceed
21 USEPA's methylmercury reference dose are "at risk" of
22 having developmentally-impaired children?
23
Response: Of course not. As I state in
24 my testimony on Page 19, the extent to which someone is
83
1 at risk above an RFD is determined by the dose response
2 relationship, not by the fact of exceeding the RFD.
3 This obvious error in interpretation of the RFD that all
4 exceedances result in risk is specifically discussed and
5 discounted in the original publication of the RFD
6 methodology by the USEPA scientists Barns and Dorsum.
7
Fourteen: You discuss the Seychelles
8 study as being negative as interpreted by the authors of
9 the study.
10
Response: Yes. I provide several
11 quotes in my testimony taken directly from the authors
12 that are omitted by the TSD and that contradict the
13 implications made in the TSD.
14
Question 14A: Please explain benchmark
15 dose analysis and what the BMDL signifies.
16
Response: Benchmark dose analysis is a
17 statistical procedure used to characterize dose response
18 relationships. USEPA defines benchmark dose as, "a dose
19 that produces a predetermined change in response rate of
20 an adverse effect compared to background." The results
21 of a benchmark dose analysis are generally used to
22 identify a statistical lower confidence limit or BMDL on
23 a dose associated with an adverse effect for the purpose
24 of estimating a level of exposure considered to be
84
1 without adverse effects such as a reference dose.
2
When data are considered negative as in
3 the Seychelles study, a benchmark dose cannot be
4 calculated because it would be infinite. However, a
5 BMDL can be calculated reflecting the nature and power
6 of the experimental design. When it is possible that
7 there is no effect of treatment, a BMDL reflects overly
8 the statistical constraints imposed by the experimental
9 design. Even when data are negative, an effect cannot
10 be completely ruled out because exposure could have
11 caused a small increase in an adverse health effect that
12 was not detected for some reason. That case a BMDL
13 represents a precautionary health protective value that
14 could be used as the basis of a reference dose for
15 health protective policy reasons. It's not a real
16 number reflecting a measured effect. It's a statistical
17 creation generated for policy reasons.
18
Question 14B: Are you aware that the
19 Seychelles investigators have published a BMD analysis
20 of their results in the children at 66 months of age and
21 more recently at 9 years of age?
22
Response: Actually, their analyses
23 produced BMDLs, not BMDs. As I just pointed out. You
24 can't calculate BMDs from negative studies.
85
1
14C: Are you aware of statement from
2 the van Wigngaarden, that's V-A-N, new word
3 W-I-G-N-G-A-A-R-D-E-N, et al., in neurotoxicology which
4 is in press and available on-line "benchmark mercury
5 concentrations of around 20 parts per million in
6 maternal hair from the nine-year follow-up of the
7 Seychelles cohort are slightly below...estimates
8 previously reported for this cohort at 66 months
9 follow-up. Additionally, they are within the range of
10 benchmark findings reported for the Faroe Islands and
11 New Zealand"?
12
Response: That question is an example
13 of how the IEPA has effectively mischaracterized the
14 conclusions of the investigators themselves. What the
15 authors actually state is, "In conclusion, benchmark
16 mercury concentrations of around 20 parts per million in
17 maternal hair from the nine-year follow-up of the
18 Seychelles cohort are slightly lower but not
19 meaningfully different from estimates previously
20 reported for this cohort after 66 months of follow-up".
21
D --
22
MR. MATOESIAN: Excuse me, but they are
23 within the range of benchmark findings reported for the
24 Faroe Islands and New Zealand. You don't dispute that?
86
1
THE WITNESS: I don't know what you mean by
2 within the range.
3
MR. MATOESIAN: Well, the second sentence in
4 that quote.
5
THE WITNESS: They're within the range of
6 benchmark findings reported for the Faroe Islands and
7 New Zealand. I guess I have to say I don't have an
8 opinion on that because I don't know who within the
9 range means here. And they're in the same order of
10 magnitude, yes.
11
D, are you aware of the following
12 statement from the Seychelles investigators (Davidson,
13 et al., neurotoxicology, in press, available on-line):
14 "Secondary analyses have generally supported the primary
15 analyses, but more recently have suggested that latent
16 or delayed effects might be emerging at exposure above
17 10 to 20 parts per million as the child matures"?
18
Response: Yes. The authors also state
19 the following: "These nonlinear analyses suggest that
20 the Seychelles study must consider the potential for
21 adverse effects of prenatal methylmercury exposure at
22 maternal hair levels above 10 to 12 parts per million,
23 but the numbers of observations in that exposure range
24 are limited. One possible interpretation of these
87
1 results is that adverse effects may be emerging as
2 children enter adolescence...the data suggest that
3 determining the true developmental effects of low level
4 prenatal exposure to methylmercury such as those
5 stemming from maternal consumption of fish during
6 pregnancy may be quite complex. Continued longitudinal
7 data collection in the Seychelles cohort as the children
8 mature is needed to confirm whether late effects of
9 prenatal exposure will appear." Thus, unlike the TSD,
10 the investigators are careful to convey the high level
11 of uncertainty associated with any conclusions based on
12 these results. The authors also state in the same paper
13 that, quote, "There is no convincing evidence for an
14 association between prenatal exposure and child
15 development in this fish-eating population ".
16
E: Are you aware that the starting
17 point (BMDL) from the Boston Naming Test from the Faroe
18 Islands study is 12 parts per million in maternal hair?
19
Response: No. I am aware that Table
20 7-2 in the National Academy of Sciences Mercury Report
21 indicates that the benchmark dose for the Boston Naming
22 Test from the Faroe Islands is 15 parts per million
23 methylmercury and maternal hair and that the BMDL is ten
24 parts per million.
88
1
Question 15: You refer to the Daniels
2 et al. study in which umbilical mercury levels were used
3 as a marker for methylmercury exposure.
4
Response: I refer to it because the TSD
5 does not, and I believe it to be a significant part of
6 any objective analysis.
7
Question A: Are you aware of any other
8 studies that used this tissue as the marker of exposure
9 in analyses of the effects of in utero exposure to
10 methylmercury on neuropsychological function of
11 children?
12
Response: Yes. In the Faroes mercury
13 concentrations were measured in stored cord tissue from
14 about half of the cohort members examined. It is a
15 marker that permits retrospective analysis of potential
16 prenatal mercury exposure. Daniels, et al. stated that
17 maternal fish intake during pregnancy was associated
18 with increased umbilical cord mercury concentrations.
19
B, are you aware of the statement in
20 Daniels et al., quote, we noted a threshold for the
21 relation between fish and cognitive development,
22 indicating benefit from eating fish in cognitive
23 development -- I don't know if I have this right --
24 indicating benefit from eating fish at least once every
89
1 two weeks, but no incremental increase in benefit with
2 more frequent fish consumption"?
3
MR. BONEBRAKE: Hang on just a second. Read
4 15B from the original.
5
THE WITNESS: Are you aware from the
6 statement in Daniels et al., quote, "We noted a
7 threshold for the relation between fish and cognitive
8 development, indicating benefit from eating fish at
9 least once every two weeks but no incremental increase
10 in benefit with more frequent fish consumption"?
11
Response: Yes. The authors also state
12 in the next sentence, quote, "This threshold could
13 indicate that some fish, but not large amounts of fish,
14 are needed to benefit development". That conclusion
15 would be consistent with the results with O-K-E-N, et
16 al."
17
C, are you aware that the average fish
18 intake in the Faroe Islands study was about two meals
19 per week and that almost half the women ate three or
20 more fish meals per week.
21
Response: I am aware that more than
22 half the participants ate between zero and two meals per
23 week while fewer than half ate more than two meals per
24 week. I'm also aware that exposure to methylmercury and
90
1 PCBs in the Faroes was higher than that reported by
2 Daniels, et al., and that an Omega-6 fatty acid rich
3 diet was consumed via whale blubber in the Faroes so the
4 beneficial effects of fish would have been substantially
5 reduced compared to Daniels et al.
6
Question 16: You refer to a talk by
7 Dr. Hibbeln on the relationship between IQ, fish intake,
8 and methylmercury exposure. Have any data from this
9 study with Dr. Hibbeln as an author been published in
10 the peer-reviewed literature?
11
Response: His work has been
12 peer-reviewed and is in press in the Lancet. The IEPA
13 relies primarily on unpublished, unpeer-reviewed studies
14 from Florida and Massachusetts to support its regulatory
15 proposal. As far as I know there are no plans to have
16 the Florida and Massachusetts studies peer-reviewed or
17 published.
18
Question B: Do you have access to the
19 results of the study so that you can make a scientific
20 determination regarding its quality?
21
Response: Not yet. Based on my
22 discussions with Dr. Hibbeln, I have no reason to
23 believe that the version soon to appear in the Lancet
24 will reflect anything other than that which he spoke
91
1 about in January.
2
Seventeen: You mention the Oken, et al.
3 study in Massachusetts of the relationship between fish
4 consumption, mercury levels in the mother, and
5 performance of the infants.
6
A: Are you aware that in that study,
7 for each increase of 1 PPM of mercury in the mother's
8 hair, the score of the baby decreased (got worse) by 7.5
9 points?
10
Response: That is what the authors
11 reported, yes.
12
B, are you aware that in an ancillary
13 analysis, performance of infants whose mothers had hair
14 levels corresponding to intake above the EPA reference
15 dose performed more poorly on the test of memory than
16 infants whose mother's hair mercury levels were below
17 the EPA reference dose.
18
Response: Yes, the 14 women whose hair
19 mercury level exceeded EPA's reference dose had children
20 who performed somewhat more poorly than the children of
21 the women who had lower hair mercury. The authors
22 concluded that, quote, "these findings based on a
23 relatively small group of women merit further
24 investigation and verification in other populations
92
1 consuming moderate amounts of seafood". In other words,
2 the authors concede that their results are basically
3 preliminary due to the small sample size. Their results
4 are not confirmed by the results in the Seychelles which
5 involved significantly higher methylmercury exposure,
6 (6.9 parts per million in hair methylmercury on
7 average), 779 infant mother pairs, and no effect on VRM
8 scores."
9
C, did you hold the position of adjunct
10 faculty member with the Harvard Center For Risk
11 Analysis?
12
Response: At one time, yes, I became an
13 adjunct faculty member so that I could work on a
14 specific project involving evaluation of the health
15 effects of siri (sic).
16
D, are you aware that in the analysis of
17 the potential benefits of fish consumption performed by
18 the Harvard Center For Risk Analysis and funded by the
19 fishing industry, the effects on the child's IQ related
20 to the mother's methylmercury intake and fish
21 consumption was estimated under various scenarios of
22 changes in fish consumption pattern, including women
23 decreasing consumption of high mercury fish while
24 maintaining the same overall fish consumption,
93
1 decreasing total fish consumption by 17 percent, or
2 increasing their fish consumption by 50 percent with no
3 regard to mercury levels?
4
Response: Yes. I'm aware of the
5 analysis.
6
E: Are you aware that, under every
7 scenario, the effect of methylmercury on IQ was greater
8 than any effect resulting from Omega-3 fatty acids, and
9 that an indiscriminate increase in fish consumption
10 resulted in a net loss of 270,000 IQ points a year?
11
Response: That's what their analysis
12 concluded under the particular assumptions made like
13 depending on linear extrapolation of neurotoxicity at
14 high methylmercury dose through the origin, and, thus,
15 assuming threshold for adverse effect. That assumption
16 is not valid based on our understanding of the
17 toxicology of methylmercury, general principles of
18 toxicology, or methods used to determine the RFD. A
19 better extrapolation would have been to consider the RFD
20 as zero risk and extrapolate existing data to this
21 point. The authors also assume that it's the entire US
22 population of reproductive-age women that
23 indiscriminately chooses to increase fish consumption
24 without choosing fish species with lower mercury levels.
94
1 According to the authors, that result translates to a
2 loss of 0.07 IQ points for every child born in the US.
3 Interestingly, the indiscriminate scenario also shows
4 that in terms of quality adjusted life years, there is a
5 net gain of 90,000 years despite calculated IQ loss
6 based on fish-reducing coronary heart disease and
7 stroke.
8
So indiscriminately increasing fish
9 consumption apparently improves life overall according
10 to the author's calculations. Benefits analyses like
11 these can be useful for the purpose of comparing policy
12 alternatives but do not reflect actual biological
13 observations. Speaking of biological observations, a
14 recent Japanese study evaluated the interaction between
15 methylmercury and Omega-3 fatty acids on developmental
16 neurotoxicity using a rat model. Exposing pregnant dams
17 consuming an Omega-3 deficient diet to methylmercury
18 produced developmental neurotoxicity in the pups.
19 Restoration of dietary Omega-3 fatty acids completely
20 eliminated developmental neurotoxicity despite exposure
21 of dams to the same dose of methylmercury. These
22 results suggest that diets with sufficient Omega-3 fatty
23 acids might alleviate the damage to higher brain
24 function caused by methylmercury.
95
1
Question 18: I'm sorry.
2
HEARING OFFICER TIPSORD: Dr. Hornshaw?
3
DR. HORNSHAW: Following up on the statement
4 you just made, and it's part of my position as the
5 chairman of the Illinois Fish Contaminant Monitoring
6 Program, I discuss with anglers occasionally what they
7 eat, and I also talk with my counter-parts at the
8 Illinois Department of Natural Resources, the field
9 staff who are also aware of what anglers are targeting
10 and taking home. And two fish species that they
11 particularly target, predator species are walleye and
12 flat-head catfish, and they actively target these fish
13 species. And I believe these two fish species are
14 notoriously low in Omega-3 fatty acids. So maybe our
15 fish advisory program is on the right track with trying
16 to keep the consumption of these fish to one meal per
17 week for women of childbearing age or in the case of the
18 Rock River, flat head catfish, one meal per month.
19 Would you agree then that the program that we're trying
20 to establish to reduce mercury in these particular
21 predator species would have important health benefits
22 for these populations that actively target high mercury
23 Omega-3 fatty acid fish?
24
THE WITNESS: That was high mercury low
96
1 Omega-3 fatty acid fish?
2
DR. HORNSHAW: Yes.
3
THE WITNESS: I'm not an expert on the
4 levels of Omega-3 fatty acids in those particular
5 species, but I do agree that overall targeting high
6 methylmercury contaminated fish is a good idea.
7
DR. HORNSHAW: And trying to reduce content
8 of mercury in this fish is also a good idea to the
9 extent that we can.
10
THE WITNESS: To the extent that that's
11 possible, yes.
12
DR. HORNSHAW: Thank you.
13
HEARING OFFICER TIPSORD: Question No. 18.
14
THE WITNESS: You mentioned that the
15 greatest source of mercury exposure in the Faroe Islands
16 was from consumption of whale meat, and that this may
17 account for the fact that effects were observed in that
18 study.
19
Response: I'm aware that the Faroe
20 Islands investigators considered whale meat to be the
21 largest source of methylmercury exposure in their
22 studies. I'm also aware that Faroes residents ate far
23 fewer fish meals than their counter-parts in the
24 Seychelles. In addition, the greatest exposure to PCBs
97
1 was from whale blubber which is why a Do Not Consume
2 advisory now exists in the Faroes for pregnant women for
3 this source of PCB contamination.
4
A, are you aware that deficits were
5 observed in the New Zealand longitudinal prospective
6 study, in which methylmercury exposure was from fish?
7
Response: Yes. I am aware that such
8 benefits were reported. I am also aware that there were
9 some technical problems with the New Zealand study, and
10 that no national or international organization has used
11 it to determine limits on methylmercury exposure.
12
B: Are you aware of a number of
13 cross-sectional studies documenting adverse effects of
14 methylmercury on neurological function in children in
15 which exposure was through fish?
16
Response: Yes. In the Portuguese
17 study, the mothers ate an average of about 2.5 meals
18 weekly, and in the Amazon study, prenatal fish
19 consumption was unknown. No neurodevelopmental effects
20 were reported in the Cree study, a population that
21 subsists on fish, although prenatal fish consumption in
22 that study was also unknown.
23
C: Are you aware that deficits were
24 related to methylmercury levels in the Oken, et al.
98
1 study in Massachusetts, in which exposure was through
2 fish?
3
Response: Yes. Average fish
4 consumption in the Oken, et al. study was 1.2 fish meals
5 weekly. As a reminder average fish intake in the
6 Seychelles was ten times higher or twelve meals per
7 week.
8
Question 19.
9
HEARING OFFICER TIPSORD: Excuse me.
10 Mr. Harley?
11
MR. HARLEY: In your response to subpart B
12 you mentioned a study, was it a Portuguese study?
13
THE WITNESS: Yes.
14
MR. HARLEY: In which effects were
15 documented at what level of consumption?
16
THE WITNESS: In the Portuguese study the
17 mothers ate an average of about 2.5 meals weekly.
18
MR. HARLEY: Two point five meals weekly.
19 In your opinion does that constitute the use of fish as
20 subsistence?
21
THE WITNESS: No.
22
MR. HARLEY: Does that constitute the use of
23 fish as a primary protein source in the areas that --
24
THE WITNESS: I don't know what the
99
1 Portuguese people in this study consumed other than
2 fish, so I can't answer that.
3
MR. HARLEY: Is there any legal limit that
4 you're aware of that would prevent a person in Illinois
5 from consuming 2.5 meals of fish weekly?
6
THE WITNESS: Legal limit in the sense that
7 you're arrested if you eat more than that?
8
MR. HARLEY: Yes.
9
THE WITNESS: I don't think so.
10
MR. HARLEY: Thank you.
11
HEARING OFFICER TIPSORD: Question No. 19.
12
THE WITNESS: You discuss the issue of
13 co-exposure to PCBs in the Faroe Islands study.
14
A: Did you hold the positions of
15 Director, Toxicology and Risk Assessment Program, NAS,
16 in 1994, and senior science advisor and project
17 director, 1992-1997?
18
Response: Yes.
19
B: Do you consider the analysis of the
20 health effects of methylmercury performed by the NAS to
21 be of high scientific quality?
22
Response: Yes. What I don't entirely
23 agree with is the Committee's referenced dose
24 recommendation which is a subject upon which reasonable
100
1 people can disagree, and, as I pointed out in my
2 testimony, is a matter of making competing policy
3 choices, not necessarily scientific ones. The fact that
4 other national and international organizations have
5 chosen different exposure limits for methylmercury based
6 on different studies illustrates my point. Moreover,
7 the NAS panel did not analyze neurotoxicity in the Faroe
8 Islands children in relationship to the contribution of
9 PCBs from mother's milk, perhaps because publications on
10 the extra ordinary contamination of this source were
11 just occurring at the time of the NAS publication. In a
12 current analysis of the methylmercury literature that
13 includes the Faroe Islands data must address this post
14 NAS analysis of PCBs in the mother's milk. In contrast,
15 the Seychelles Islands also analyzed for PCB exposures
16 and did not find any. Thus, it is not surprising that
17 the Faroes and Seychelles Island studies, while equally
18 well-done, in many respects have different outcomes.
19
C: Are you aware that the correlation
20 between PCB and mercury levels of the mothers of the
21 Farroe Islands study was 0.28-0.42, depending on the
22 congener.
23
Response: Grandjean, et al., 2001,
24 reported as 0.42 in their abstract on Page 305 and
101
1 conclude on that basis that, quote, the association
2 between cord, PCB and cord blood mercury suggested
3 possible confounding".
4
G, is there any reason to believe that
5 postnatal PCB exposure would be highly correlated with
6 in utero mercury exposure, given that PCB levels in
7 breast milk would be similar to levels in the mother's
8 blood or cord tissue (on a lipid basis)."
9
Response: No. In any case, the Faroe
10 investigators evaluated PCB exposure for fewer than half
11 of the study participants. However, this question
12 misses the key toxicologic difference between the Faroe
13 and Seychelles Islands. PCB's exposures were, on
14 average, twice as high in Faroe children as were fed to
15 infant monkeys given a mixture of PCB similar to that
16 found in Faroe mother's milk. Infant monkeys developed
17 neurological problems after such exposure. Faroe
18 children also developed neurological problems after
19 higher PCB exposures. Seychelles children receiving
20 even higher doses of methylmercury than Faroe children
21 but without the PCB exposures did not develop
22 neurotoxicity. The logical conclusion is that the Faroe
23 children were exposed to something that caused
24 neurotoxicity besides methylmercury. Their exposure to
102
1 600 times EPA's referenced dose for PCBs, a known
2 neurotoxicant, is the most likely candidate for the
3 toxicity in the Faroes, but not the Seychelles -- the
4 additional toxicity evoked in the Faroes, but not the
5 Seychelles' children. NAS did not study the toxicity
6 from PCB exposure to the Faroe children for mother's
7 milk.
8
E: Is there a reason to believe, or
9 data to support, the hypotheses that the length the
10 breast feeding which would be a major determinant of the
11 postnatal PCB exposure to the infant, would be
12 correlated with prenatal methylmercury exposure?
13
Response: No. However, the length of
14 breast feeding would be a major determinant of PCB
15 exposure in Faroe children. The NAS did not study this
16 likely source of neurotoxicity in Faroe children.
17
F: Isn't it the case that if prenatal
18 exposure to methylmercury and postnatal PCB exposure are
19 not correlated, postnatal PCB exposure cannot be
20 responsible for effects attributable to methylmercury?
21
Response: No. Methylmercury exposure
22 is occurring postnatally as well. And at no time have I
23 said that the effects attributed to methylmercury should
24 be attributed to PCBs instead. I have said that it is
103
1 certainly biologically plausible given the toxicology
2 and exposure information that is available for PCBs that
3 the effects observed are due to the combined exposure.
4 The Faroe's investigators have stated that, "the
5 possible neurotoxic influence of PCB exposure did not
6 explain the methylmercury associated neurobehavioral
7 deficits." Which means that PCBs alone did not account
8 for the observations, but that their potential
9 contribution to the outcomes cannot be ruled out.
10
MR. MATOESIAN: Excuse me. Is there a
11 synergistic effect between methylmercury and PCBs?
12
THE WITNESS: A synergistic effect? By that
13 you mean greater than additive?
14
MR. MATOESIAN: Yeah, yeah.
15
THE WITNESS: I don't think we know.
16
MR. MATOESIAN: Do you have some scientists
17 postulate that there may be?
18
THE WITNESS: No. What I know is that PCBs
19 affect the same end points apparently that methylmercury
20 can affect. So if one is exposed to both of them, one
21 might presume that you would see at least an additive
22 effect. I don't know whether it would be greater than
23 additive or not.
24
MR. MATOESIAN: Okay.
104
1
THE WITNESS: G: Are you aware that the
2 Faroe Islands investigators published results in 2006
3 from these same children at 14 years of age and
4 methylmercury-related effects continued to be observed
5 but that no effects of PCBs were identified?
6
Response: I am aware, actually, that
7 the 2006 results showed that the correlation between
8 prenatal PCB exposure which was available for only half
9 the subjects showed "weak associations with outcomes
10 that did not reach statistical significance". I am also
11 aware that at an earlier study when the Faroe Islands'
12 investigators controlled for the effects of prenatal
13 exposure to PCBs, the correlation between methylmercury
14 exposure and poorer performance on the Boston naming
15 test was no longer statistically significant. Those
16 results are consistent with a contributory role played
17 by PCBs. Perhaps more importantly, PCB exposures by way
18 of mother's milk to Faroe Islands inference used to
19 determine USEPA'S RSD should be further studied. Nearly
20 all of those infants were breast-fed but for differing
21 times. Published PCB levels in mother's milk varied
22 among women. It follows that these infants had unknown
23 but likely different PCB exposures. It is these
24 exposures to PCBs that should be studied in relationship
105
1 to neurotoxicity outcome."
2
Twenty: You discuss the review of
3 exposure to PCBs on neuropsychological function in
4 children by Schantz, Widholm, and Rice.
5
A: Are you aware that in addition to
6 discussing the 1997 paper by the Faroe Islands group on
7 the effects of methylmercury at seven years of age,
8 Schantz, et al., also discuss a 2001 analysis of the
9 effects of PCBs in this same study?
10
Response: Yes.
11
B: Are you aware of the conclusion from
12 that subsequent analysis: "After adjusting for mercury
13 exposure in the statistical analysis, the association of
14 test scores with PCB exposure was reduced to a
15 nonsignificant level on both the Boston Naming Test and
16 the CPT" (Schantz et al., Page 366)?
17
Response: That statement does not
18 appear on Page 366. It appears on 368. It is a
19 conclusion stated by Schantz, et al., not by Grandjean,
20 et al., 2001. Here is what Grandjean, et al., concludes
21 regarding their own study in the Faroes: "While no PCB
22 effects were apparent in children with low mercury
23 exposure, PCB-associated deficits within the highest
24 tertile of mercury exposure indicated a possible
106
1 interaction between the two neurotoxicants. The limited
2 PCB-related neurotoxicity in this cohort appears to be
3 affected by concomitant methylmercury exposure".
4
Grandjean, et al, 2001 also state,
5 quote, "The results of this study suggest that in the
6 Faroese population, methylmercury neurotoxicity may be a
7 greater hazard than that associated with PCB, but PCB
8 could possibly augment the neurobehavioral deficits at
9 increased levels of mercury exposure."
10
Interestingly on Page 374 of the
11 Schantz, et al. paper, (co-authored by Rice) the
12 following conclusion is reached: "As the data from
13 ongoing PCB studies are published, the weight of
14 evidence for PCB effects of neurodevelopment is growing.
15 In particular, studies in Taiwan, Michigan, Oswego, New
16 York, the Netherlands, Germany, and the Faroe Islands
17 have now all reported negative associations between
18 prenatal PCB exposure and measures of cognitive
19 functioning in infancy or childhood". In other words,
20 many studies indicate that as PCB exposure increased,
21 cognitive functioning decreased.
22
I am also aware that USEPA must have
23 been concerned about the potential contribution PCBs
24 might be making to the outcome because it calculated
107
1 BMDLs both adjusted and unadjusted for PCBs.
2
C: Are you aware that there was no
3 indication of any effects of PCBs in this study when the
4 children were 14 years old?
5
I responded to that question already
6 when I responded to Question 19G.
7
HEARING OFFICER TIPSORD: Dr. Hornshaw?
8
DR. HORNSHAW: Dr. Chapman mentioned that
9 there are a number of impaired waters that have both
10 PCBs and mercury as the cause of impairment. If we
11 accept that PCBs and mercury have additive effects,
12 wouldn't that make it even more important to control
13 mercury as much as possible for these waters?
14
THE WITNESS: I think it would be important
15 to control both methylmercury and PCBs.
16
DR. HORNSHAW: PCBs are almost entirely a
17 legacy contaminant for which we have no realistic means
18 for control which means if we're going to control
19 anything, it has to be mercury. Would you agree with
20 that?
21
THE WITNESS: Yes.
22
MR. BONEBRAKE: I'll just object to that.
23 It calls for a legal conclusion, but you've answered it.
24
MR. MATOESIAN: Can I just ask you a
108
1 question then? So are you suggesting that we should be
2 more concerned about cleaning up PCBs?
3
THE WITNESS: I'm not really extrapolating
4 that statement to anything about risk management
5 strategy. I'm simply pointing out that USEPA's
6 reference dose and the National Academy of Science's
7 report which was the subject of this question did not
8 address exposure to PCBs postnatally.
9
MR. MATOESIAN: But in general concerning
10 PCBs and mercury, if we -- there's been a lot of
11 testimony, I guess, about PCBs, but if those were
12 somehow taken care of, wouldn't the issue still exist
13 about mercury in the waters?
14
THE WITNESS: Yes.
15
MR. MATOESIAN: So wouldn't, again, you need
16 to control them both?
17
THE WITNESS: Yes.
18
MR. BONEBRAKE: I'm not clear what you -- to
19 accomplish what results, Mr. Matoesian?
20
MR. MATOESIAN: Well, for instance, to
21 reduce or eliminate the fish consumption advisories.
22
THE WITNESS: I'm sorry. Start at the
23 beginning of the question again.
24
MR. MATOESIAN: Well, if we wanted to get
109
1 rid of the fish advisory so that people could eat as
2 many fish as they wanted to, you'd have to get rid of
3 both factors, correct?
4
THE WITNESS: I think -- No, that's not
5 what I'm saying. What I'm saying is that when you look
6 at the neurotoxicity of methylmercury in the Faroe
7 Islands, you need to include consideration of postnatal
8 exposure to PCBs. And what that means is that because
9 the USEPA's reference dose is based on just the
10 methylmercury in that study, it is more stringent than
11 it would be if the PCB's exposure had also been
12 accounted for. So if you were to operate from a
13 different reference dose, for example, then you might
14 make different decisions about the nature and extent of
15 reducing methylmercury exposure in fish.
16
MR. MATOESIAN: But you agree that that's a
17 reasonable policy decision?
18
THE WITNESS: Which is a reasonable policy
19 decision? To reduce methylmercury?
20
MR. MATOESIAN: To establish the reference
21 dose that USEPA did? Isn't that what you state on
22 Page 19?
23
MR. BONEBRAKE: I'm sorry. Are you
24 referring us to a particular page?
110
1
MR. MATOESIAN: Yes. Different factors were
2 used, but then I believe equally competent.
3
MR. BONEBRAKE: Page 19 was it?
4
MR. MATOESIAN: I believe so.
5
MR. BONEBRAKE: Can you point us to some
6 text on that page, please.
7
MR. MATOESIAN: Yes. I'm sorry. I lost it.
8 It was 15, the last paragraph. Can you just explain how
9 none of those choices are necessarily right or wrong and
10 different policy choices made by equally competent
11 scientists looking at the same data.
12
So you're not suggesting that there's
13 anything wrong with EPA's establishing a reference dose;
14 is that correct?
15
THE WITNESS: I think that in that case it
16 failed to include consideration of concomitant exposure
17 to PCBs, and, therefore, is inaccurate to the extent
18 that an RFD can be accurate or inaccurate. I guess what
19 I'm trying to say is that I think that it's based on
20 erroneous assumptions.
21
DR. HORNSHAW: Isn't a large portion of the
22 US population also exposed to PCBs?
23
THE WITNESS: I don't know.
24
MR. MATOESIAN: What about Illinois?
111
1
THE WITNESS: I don't know. I don't have
2 personal knowledge of your PCB exposure.
3
MR. MATOESIAN: Well, you state on Page 6
4 that, the one full paragraph, the last two sentences,
5 you say mercury emissions in Illinois may or may not
6 affect the mercury levels in Illinois fish, and even if
7 it does, reducing Illinois methylmercury fish tissue
8 concentrations to below the Illinois fish tissue mercury
9 consumption advisory levels will not eliminate fish
10 consumption advisories in Illinois because of the
11 presence in Illinois fish or substitutes such as
12 polychlorinated biphenyls.
13
THE WITNESS: Yeah. And I based that
14 statement on the testimony of Peter Chapman.
15
MR. MATOESIAN: So you're using his
16 information?
17
THE WITNESS: Correct.
18
MR. MATOESIAN: And assuming that his
19 information is correct?
20
THE WITNESS: Correct.
21
MS. BASSI: Mr. Matoesian, is it not
22 correct?
23
MR. MATOESIAN: Well, I just want to be sure
24 if she did that independently or if she's just using --
112
1
HEARING OFFICER TIPSORD: I would note that
2 you just asked a question of the attorney.
3
MR. MATOESIAN: Not that I'm sworn in.
4 Thank you.
5
MS. BASSI: Clarifying his question.
6
MR. BONEBRAKE: Move on then.
7
HEARING OFFICER TIPSORD: Question No. 21.
8
THE WITNESS: You discussed the issue of
9 levels of mercury in the mothers of the large
10 epidemiological studies reviewed by the NAS compared to
11 those in the U.S. population.
12
A: Are you aware that according to the
13 NAS modeling in the Faroe Islands study there is no
14 evidence of a threshold within the range of exposures in
15 the study down to about one microgram per liter in cord
16 blood.
17
Response: No. The dose response
18 modeling performed by the NAS is consistent with a less
19 than linear response or sublinearity; that is, their
20 modeling does not rule out a threshold. Committee
21 states on Page 294, quote, "sublinear models would be
22 appropriate, for instance, in the presence of a
23 threshold," and then proceeds to apply the K power model
24 which is consistent with sublinearity to calculate
113
1 benchmark doses."
2
B: Are you aware that an umbilical
3 blood level of 1 microgram per liter would be an average
4 equivalent to a maternal blood level of 0.6 micrograms
5 per liter based on an analysis of a dozen papers of the
6 relationship between maternal and cord blood, and that
7 an RFD based on that difference would be below the level
8 of -- I'm sorry -- the question that's being asked is
9 and that this is below the level of half of the women in
10 the U.S. of reproductive age?
11
I did not understand the question. I
12 did not understand what "this is" referred to. I think
13 what's meant is, and the last phrase of the question
14 would be, "and that an RFD based on that difference
15 would be below the level of half the women in the U.S.
16 of reproductive age." Is that what is meant?
17
MR. MATOESIAN: Yes.
18
THE WITNESS: Response: According to the
19 authors of that analysis, yes, one microgram per liter
20 cord blood is equivalent to 0.6 micrograms per liter
21 maternal blood. However, one of the authors of that
22 study served on the NAS Mercury Committee, and yet that
23 committee did not choose to make any adjustments along
24 those lines assuming, instead, a one-to-one
114
1 relationship. USEPA also believed their analysis to be
2 too uncertain to draw such a conclusion and chose to use
3 a one-to-one assumption. Furthermore, both the NAS and
4 USEPA used an uncertainty factor for within human
5 variability to address this and other unknowns.
6
As for the second part of the question,
7 no, an RFD based on that difference would not result in
8 one half of US women of reproductive age being below it.
9 If an adjustment were made consistent with that cord
10 blood maternal blood differential, the RFD would
11 actually go up; that is, be less stringent than the
12 current RFD, and there would be few or no women above
13 it. A ten-fold uncertainty factor which is what USEPA
14 now uses for methylmercury, comprises two components:
15 Three for toxicokinetic differences or differences in
16 how the body handles the chemical, and three for
17 toxicodynamic differences or differences in
18 susceptibility to the toxicity of a chemical. If we
19 were to replace the toxicokinetic part of the ten-fold
20 uncertainty factor with an adjustment for the maternal
21 blood cord blood differential, we would use the default
22 factor of three for the remaining toxicodynamic part of
23 the uncertainty factor. The resulting RFD would be BMDL
24 times 0.6 divided by three which is approximately
115
1 two-fold higher than the current RFD. Interestingly,
2 according to a report by Iwasaki, more than 90 percent
3 of Japanese women have mercury levels that exceed
4 USEPA's current reference dose for methylmercury. As
5 far as I know there is no epidemic of poor
6 neurodevelopmental performance in Japan.
7
MR. BONEBRAKE: Could you spell Iwasaki for
8 the court reporter.
9
THE WITNESS: I-W-A-S-A-K-I.
10
C, are you aware that when the Faroe
11 Islands children were tested again at 14 years, deficits
12 were also observed starting at the lowest exposures as
13 evidenced by the graphic presentations in the
14 publication?
15
Response: No. The graphic
16 presentations do not show that. They showed the
17 associations between cord blood mercury level and
18 continuous performance test reaction time for Boston
19 Naming Test scores. They do not show where the results
20 become abnormal or significantly different from each
21 other. They simply show the distribution of results.
22 There are no unexposed children in the Faroes study, so
23 there is no true control group; and, therefore, no basis
24 to distinguish effects at the lowest exposures from
116
1 those of an unexposed group.
2
D: Are you aware that at both 7 and 14
3 years, the relationship between exposure and effect was
4 log-linear; in other words, that effects were relatively
5 greater at lower exposures?
6
Response: No, they were not. According
7 to the NASA Mercury Committee, the most biologically
8 plausible dose response model was not log-linear. It
9 was the K power model specifically ruling out super
10 linearity for a log -- supralinearity or a log-linear
11 relationship. "The Committee believes that an additive
12 (linear) or perhaps sublinear model is the most
13 justifiable from a biological perspective, thus ruling
14 out square root and log transformed models. The
15 Committee concludes that considerable caution should be
16 used in fitting models based on log or square root
17 transformations of exposure which might not be
18 appropriate in dose response settings such as those for
19 methylmercury where there are no internal controls and
20 where the dose response is relatively flat."
21
Question 22.
22
HEARING OFFICER TIPSORD: Actually, we have
23 E, F, G, and H of Question 21 still.
24
MR. BONEBRAKE: We may have had a mistake in
117
1 duplicating. So we'll move on to the next question and
2 circle back. Would that be acceptable?
3
HEARING OFFICER TIPSORD: If we need to,
4 yes. Go ahead.
5
THE WITNESS: I don't have the other
6 questions in front of me, so there's obviously been an
7 error.
8
Let's move on to 20 for now, I guess.
9 You state that USEPA did not include the Seychelles
10 study in the derivation of the reference dose.
11
A: Are you aware that the NAS performed
12 an integrative analysis including all three studies:
13 The Faroe Islands, Seychelles, and New Zealand?
14
Response: Yes. And then the NAS
15 excluded the integrative analysis as the basis for a
16 reference dose considering it, quote, premature, end
17 quote, and, quote, exploratory, end quote.
18
B, are you aware that EPA derived
19 exploratory reference doses based on a number of end
20 points, including the integrative analysis, and that
21 this analysis also yielded a reference dose of 0.1
22 micrograms per kilogram per day?
23
Response: Yes. And then EPA chose
24 one end point to carry through the dose conversion and
118
1 application of the uncertainty factor to calculate the
2 RFD; namely, the NRC recommended BMDL of 58 parts per
3 billion mercury and cord blood from the Boston Naming
4 Test.
5
C: Are you aware that the BMDL from the
6 integrative analysis is 34 micrograms per liter mercury
7 in blood, lower than the 58 micrograms per liter for the
8 Boston Naming Test for the Faroe Islands study?
9
Response: I am aware that, according to
10 the NAS Committee, quote, "The integrative analysis does
11 not permit the direct calculation of a BMDL". I am also
12 aware that the EPA's, USEPA's water quality criterion
13 document for mercury lists 32 micrograms per liter
14 mercury in blood as a quote, unquote, BMDL, not 34.
15 And, just as a reminder, you can't actually compare
16 BMDLs. You can't compare a statistical lower bounds as
17 they reflect study design, not comparative toxicity. It
18 is not surprising that a BMDL based on three widely
19 divergent studies might be lower than a BMDL based on a
20 single end point from a single study."
21
D: Are you aware that the reference
22 doses from the New Zealand study were lower than those
23 from the Faroe Islands or Seychelles, and that if EPA
24 had relied on the New Zealand study, the reference dose
119
1 may have been lower than the current 0.1 micrograms per
2 kilogram per day as evidenced in the IRIS summary?
3
Response: I am aware that a lower
4 reference dose can be calculated based on the New
5 Zealand data. I am also aware that neither the NAS
6 Committee nor EPA considered the New Zealand data to be
7 appropriate as the basis for calculating a reference
8 dose. I am also aware that other organizations have
9 calculated reference dose equivalent either equal to or
10 less stringent than EPA's calculation and none relied on
11 the New Zealand study. The principal reason that the
12 New Zealand study is not used as the basis of any
13 group's safe dose assessment is that the determinations
14 of a BMDL from this study is highly dependent on the
15 results of one individual. When this individual is
16 excluded, a BMDL from the New Zealand study is similar
17 to that derived from the Faroes. When this individual
18 is included, a BMDL from the New Zealand study is
19 similar to that derived from the Seychelles. Since the
20 New Zealand study can be used to support either the
21 results of the Faroes or the Seychelles depending on the
22 exclusion or inclusion of results from one individual,
23 the study is not strong enough to serve as the sole
24 basis of the RFD, nor can it be used to support either
120
1 the reports of the Faroes' or the Seychelles' studies
2 except in a general sense.
3
E, are you aware that the hair level
4 that may be associated with the deficits in the
5 Seychelles study at nine years, 12 parts per million in
6 maternal hair, is the same as the point of departure for
7 the EPA reference dose?
8
Response: I am aware that the authors
9 of the Seychelles study reported that at nine years, the
10 average BMDL across 26 endpoints was 20 parts per
11 billion in maternal hair with a range of 17 to 23 parts
12 per million, not 12.
13
F: Are you aware that the analysis by
14 Dr. Louise Ryan of Harvard University calculated that
15 the IQ loss in the children associated with increased
16 maternal hair mercury levels was almost identical for
17 all three studies?
18
Response: As I pointed out already,
19 neither did the New Zealand nor the Seychelles Island
20 studies reported a statistically significant IQ deficit,
21 and the Faroe Islands study did not evaluate IQ, so that
22 effect had to be estimated based on other endpoints.
23 Dr. Ryan used IQ as a surrogate for other effects in
24 order to monetize potential effects of methylmercury
121
1 exposure for the purpose of performing a regulatory
2 impact analysis.
3
Twenty-three: Please state the
4 definition of the reference dose according to USEPA.
5
Response: "An estimate, (with
6 uncertainty spanning perhaps an order of magnitude) of a
7 daily oral exposure to the human population (including
8 sensitive sub groups) that is likely to be without an
9 appreciable risk of deleterious effects during a
10 lifetime".
11
A, does this definition include the
12 phrase "with uncertainty spanning perhaps an order of
13 magnitude"?
14
Response: Yes.
15
B: Is there anything in the definition
16 that indicates that there is any more certainty
17 concerning the level at which adverse effects occur
18 below the reference dose than above it?
19
Response: Yes. By definition. The
20 phrase, quote, likely to be without an appreciable risk
21 of deleterious effects during a lifetime" indicates that
22 risks at or below the reference dose are unlikely. In
23 addition, the original publication on USEPA's RFD
24 methodology addresses the likelihood of risks both above
122
1 and below the RFD and concludes that more certainty
2 exists with regard to adverse effects occurring above
3 the RFD than below."
4
C, is there any reason to believe that
5 there is certainty about the lack of risk of adverse
6 effects below the reference dose compared to the risk of
7 adverse effects above it?
8
Response: The precautionary approach
9 that USEPA takes to determine reference doses account
10 for uncertainty in order to identify a dose below which
11 no effects are anticipated. Because of that
12 precautionary approach, risks below a reference dose are
13 unlikely and risks above it depend on the shape of the
14 dose response curve of concern. As I state in my
15 testimony, "USEPA is careful to point out that while
16 exposure at or below a reference dose indicates that a
17 health risk is unlikely, people who are exposed to a
18 substance above its reference dose should not be
19 considered at risk: "... exceeding the reference dose
20 is not a statement of risk." USEPA's regulatory impact
21 assessment for the Clean Air Mercury Rule states, "It is
22 also important to note that the reference dose does not
23 define a right line above which individuals are at risk
24 of adverse effects".
123
1
In other words, while exposures at or
2 below a reference dose are unlikely to pose a risk, the
3 converse, that exposures exceeding a reference dose are
4 likely to pose a risk, is not the case." And that's the
5 end of the quote from my testimony.
6
Furthermore, the methylmercury RFD is
7 based on observations from the most sensitive life stage
8 of humans, the species and life stage we want to
9 protect. There is no interspecies extrapolation
10 required, removing an important source of uncertainty.
11 An entrust species uncertainty factor of ten has been
12 applied just in case there are kids who could be even
13 more sensitive than the group of kids tested. The
14 benchmark dose upon which the RFD is based is a
15 conservative lower bound; in other words, accounts for
16 uncertainty by erring on the side of protecting children
17 on a 5 percent likelihood of poor performance on the
18 Boston Naming Test. And, remember, none of the kids in
19 the Seychelles appears to have problems at even higher
20 methylmercury exposure levels. Thus, there is no reason
21 to believe that there is uncertainty about the lack of
22 risk of adverse effects below the reference dose
23 compared to the risk of adverse effects above it.
24 Moreover, ensuring that more certainty exists about the
124
1 lack of risk of adverse effects at or below the
2 reference dose when compared to the lack of risk of
3 adverse effects above it is standard operating procedure
4 by USEPA and other health groups around the world. This
5 standard operating procedure is based on sound
6 toxicologic principles that have been studied and
7 accepted by all erudite practitioners of risk analysis.
8
I'm getting a sore throat.
9
HEARING OFFICER TIPSORD: You have one
10 question left.
11
You know what, let's go ahead. Let's go
12 ahead and take lunch break and we'll come back.
13
(At which time a lunch
14
break was taken.)
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1 STATE OF ILLINOIS )
) SS:
2 COUNTY OF COOK )
3
I, Laura Bernar, a Notary Public within and for
4 the County of Cook and State of Illinois, and a
5 Certified Shorthand Reporter of the State of Illinois,
6 do hereby certify that I reported in shorthand the
7 proceedings had at the taking of said hearing and that
8 the foregoing is a true, complete, and correct
9 transcript of my shorthand notes so taken as aforesaid,
10 and contains all the proceedings given at said hearing.
11
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__________________
13
LAURA BERNAR, CSR
CSR NO. 084-003592
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