Fluoride Action Network

New study finds cancer rate higher in C8-exposed areas

Source: The Parkersburg News and Sentinel (West Virginia) | May 6th, 2004 | By Pamela Brust
Industry type: Perfluorinated chemicals

PARKERSBURG – A recently released study authored by Dr. James Dahlgren, a nationally known toxicologist retained by plaintiffs in a pending Wood County Circuit Court C8 class action lawsuit filed against DuPont Washington Works, states “the overall cancer prevalence rate is higher in the population exposed to C8 when compared to the general population.”

Perfluorooctanonic Acid (PFOA), a man-made perfluorooctaned chemical also referred to as C8, is a key ingredient agent in the production of Teflon and other fluorochemical products.

DuPont officials issued a statement refuting the claims made in Dahlgren’s report and questioned the scientific validity of his study.

According to Dahlgren’s report, the aim of the study “was to compare cancer distribution and cancer prevalence rates in a PFOA-exposed population (residents) to that of the industry cancer registry data from an occupational exposed population and finally to the general population. We performed a questionnaire on 599 residents living near DuPont Washington Works.”

Cancer registry data from the PFOA DuPont workers was made available through discovery motions filed in connection with the pending litigation against DuPont, according to the report.

“The overall cancer prevalence rate is higher in the PFOA-exposed population when compared to the general population,” according to the report.

“The residents from age 24 to 65 have a significantly higher rate of prevalence cancer when compared to the general population,” according to the study.

“Our findings indicate that the exposed residential population (residents) have similar cancer prevalence findings to the PFOA exposed workers. Prostate cancer in the workers was proportionately elevated among young age males,” the report states.

The report also notes findings of elevated prevalence rates of atypical cancers such as Hodgkin’s, Leukemia and Multiple Myeloma. This data suggest that exposure to PFOA may alter cancer distribution in exposed populations (worker and residents) and may be an important risk factor for an excess of cancer cases,” according to Dahlgren’s report.

DuPont has challenged Dahlgren’s findings.

“DuPont’s position is very clear: PFOA is not a human carcinogen and there are no known health effects associated with PFOA. Dahlgren’s claims are inaccurate and inconsistent with published scientific studies. In fact, the more we study PFOA, the more confident we are in our conclusions that PFOA is safe,” said Dr. Robert Rickard, DuPont’s lead toxicologist.

“Based on what we have seen, we question the scientific validity of the conclusion in the Dahlgren report. It is clear from the abstract of the paper, and the methodology reported at a recent meeting in Europe, that the analysis do not represent the scientific approach used by epidemiologists. There is no indication that other factors impacting the health of populations were considered or analyzed,” said Dr. Robin Leonard, principal epidemiologist for DuPont.

“Appropriate comparisons were not made using age-adjusted, standardized populations, which results in conclusions that are unfounded; recruitment (of residents) for the report was made through radio and television advertising; there is no evidence that it reflects an accurate representation of the community,” Leonard said.

“The report purports to use DuPont data as a cancer prevalence rate comparison, yet DuPont did not report prevalence data. We reported 50 years of age-adjusted, cumulative incidence data and rates. It is inappropriate to compare DuPont data with resident prevalence data.

“Finally, the report does not measure PFOA exposure at the individual level so no estimate of risk due to PFOA exposure can be made. The report focused only on occurrence of cancer and did not take into consideration any lifestyle or medical history, all of which were captured in the questionnaire given to the residents but were not analyzed,” Leonard said.

Copies of Dahlgren’s report and related information have been turned over to the U.S. Environmental Protection Agency and the files are available to the public. Dahlgren presented the results of his C8 study at the recent annual meeting of the Society of Environmental Toxicologists and Chemists in Prague, Czech, Republic.

DuPont recently announced plans to conduct its own $1 million study to compare the health of employees who work directly with C8 and those who do not.

Rickard earlier stated no new data prompted the decision to conduct the survey.

Plaintiffs in the pending lawsuit allege DuPont intentionally withheld and misrepresented information concerning the nature and extent of the human health threat posed by the C8 from DuPont in drinking water supplies. They are claiming C8 damaged their health and increased their risk for additional health problems.