[Date Prev][Date Next][Date Index]
E-M:/ what DEQ wanted to say about the Dow November 2004 community update
- Subject: E-M:/ what DEQ wanted to say about the Dow November 2004 community update
- From: "Dave Dempsey" <email@example.com>
- Date: Fri, 25 Feb 2005 22:49:36 -0500
- Delivered-to: firstname.lastname@example.org
- Delivered-to: email@example.com
- List-name: Enviro-Mich
- Reply-to: "Dave Dempsey" <firstname.lastname@example.org>
Enviro-Mich message from "Dave Dempsey" <email@example.com>
Pardon the long post, but I agree with DEQ communications director Patricia
Spitzley that "The more information and education people can receive about
the effects of dioxin the better." In that spirit, here are the full DEQ
staff draft comments on Dow's November community update that were, for some
reason, never released.
Comments on Dow?s November 2004 Community Update
1. Page 1, Column 1, Paragraph 2: This is an overly generalized and
ambiguous statement. The Environmental Protection Agency, International
Agency for Research on Cancer (IARC), U.S. Department of Health and Human
Services, and other government organizations recognize 2,3,7,8-TCDD as a
known human carcinogen and dioxin mixtures (toxic equivalence or TEQ) as
suspected or probable human carcinogen.
2. Page 1, Columns 2 and 3: It is difficult to review this section because
Dow would not provide the actual study results or even a copy of the
Powerpoint presentation given to staff of the Departments of Community
Health (DCH) and Environmental Quality on November 3, 2004. DCH staff
requested this information on November 4, 2004. Dr. Michael Carson of Dow
declined to provide the requested information.
3. Page 1, Column 2, Paragraph 3: The heading of this section states ?No
Indication of Health Effects? and the text indicates that Dow finds ?little
indication of any health effect related to dioxin exposure in our
4. Page 1, Columns 2 and 3, Paragraph 6: In 2004, this is the range Dow
reports. Dioxin is eliminated from the body with a half life of
approximately seven years. If the Dow reported levels are corrected for
elimination via half life, this range would be much higher. It is not
accurate to compare the 2004 Dow data to the levels reported by the Centers
for Disease Control which are the estimated highest serum levels at the time
of last exposure.
5. Page 1, Columns 3, Paragraph 2: The section, ?People More Resistant,? is
misleading. The statement cited is not proven for all adverse effects that
have been associated with dioxin exposure. For example, for effects that
have been clearly associated with dioxin exposure, such as chloracne and the
induction of liver enzymes, humans and animals respond at similar body
burdens. For some effects, humans are more sensitive than certain other
mammalian species (e.g., chloracne in mice, cancer in hamsters, decreased
testosterone in rats).
6. Page 2, Column1, Paragraph 4: The more comprehensive studies by National
Institute for Occupational Safety and Health (NIOSH) and IARC do show
increased risk of disease (cancer, ischemic heart disease). These results
were reaffirmed in 2004. Dow should cite the study to which they referred.
7. Page 2, Column 2, Paragraph 4: The bioavailability study design has not
been approved by the DEQ. An independent peer review by Toxicology
Excellence in Risk Assessment (TERA) indicates that there are major problems
with the study design. In addition, it has not been demonstrated at this
location that dioxins are ?firmly bound? to soil and are not readily
absorbed into the blood. In fact, based on Dow?s wild game study and
Michigan State University?s (MSU) ecological risk studies, dioxins in the
Tittabawassee River floodplain appear to be very bioavailable.
The German study referred to in this discussion may not be relevant as
bioavailability varies based, in part, on soil type and contamination.
8. Page 3, Columns 2 and 3: Dow?s graphs and comparisons are flat out
misrepresentations of the actual facts, data, and model for the DEQ?s
screening level terrestrial ecological risk assessment (ERA) evaluation.
The DEQ made no estimates of the level of contamination expected to be
present in squirrels and turkeys from the Tittabawassee River floodplain.
It would have been, and is, inappropriate to use the DEQ?s screening level
terrestrial ERA to attempt to make such calculations.
The DEQ was, in fact, surprised by the high levels of dioxins found in the
portions of squirrels, turkeys, and deer consumed by humans. Higher levels
of contamination are expected to be present in portions of animals that are
consumed by prey species. The recently released MSU ecological data support
the DEQ?s conclusion that ecological risk from dioxins is present in the
Tittabawassee River floodplain. Levels of dioxin in small ground dwelling
mammals is on the order of 100 times higher than the squirrel data reported
9. Page 4, Column 3, Paragraph 1: The ?guidelines? referred to in this
paragraph are actually concentration ranges. Exposure to these
concentration ranges may result in adverse health effects. Some studies in
humans have shown adverse health effects associated with background levels
10. Page 5, Columns 1 and 2: The Interim Response Activities (IRAs)
referred to in this section have not been approved by the DEQ. This section
does not discuss critical components of the IRAs, which include advisory
signage to reduce exposure to contaminated soil and fish.
Please note that ?permit approval? likely refers to floodplain permits, not
Part 111 approval of the IRAs for corrective action purposes as is implied
by the wording.
11. Page 5, Column 3, Paragraph 1: Based on Dow?s November 3, 2004
presentation to DCH and DEQ staff, chloracne did not predict serum dioxin
levels (i.e., some workers with high dioxin levels did not exhibit
Dow?s exposure estimates did not predict actual measured dioxin levels as
stated in this paragraph. Instead, they predicted relative levels of
12. Page 5, Column 7: Although Dow briefed DCH and DEQ staff on the worker
study, Dow declined to provide the actual study results when requested to do
so on November 4, 2004.
13. Page 6, Column 2, Paragraph 2: A publication of the study cited by Dow
supports the TEQ approach, which is an order of magnitude estimate of
overall toxic potency (not just cancer). Also, it should be clarified that
toxic equivalency factors (TEFs) are developed based on specific toxicity
studies of the individual compounds. The TEF for 2,3,4,7,8-PeCDF (not
2,4,7,8-PCDF) estimated from this study were 0.16 to 0.34 for four tumor
types, which are within half an order of magnitude of the current TEF of
0.5. The study cited here also verified that the cancer incidence from a
mixture of three dioxin-like compounds was adequately predicted by the TEF
approach and did not over-predict toxicity as implied by Dow.
14. Page 7, Column 1, Paragraphs 3 and 4: The University of Michigan Dioxin
Exposure Study (UMDES) as designed will not be able to conclusively
determine the exposure of the specific population of greatest concern,
residents who live on properties that frequently flood. Also, as noted
above, even if these residents have dioxin levels within the background
range, it does not mean that there will be no increased health risk.
The DEQ will not be able to use the UMDES for corrective action purposes as
described here. In addition, it is not appropriate to wait until the study
is completed in 2007 to begin to take actions to reduce exposure.
ENVIRO-MICH: Internet List and Forum for Michigan Environmental
and Conservation Issues and Michigan-based Citizen Action. Archives at
Postings to: firstname.lastname@example.org For info, send email to
email@example.com with a one-line message body of "info enviro-mich"