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EWG Urges Censure of 'Brockovich' Scientist

For Immediate Release: 
Tuesday, July 18, 2006

(WASHINGTON, July 18) — A scientific consultant whose firm fraudulently planted a study rebutting a link between chromium and cancer should be censured for violating toxicology's professional code of ethics, said the watchdog group whose investigation led to the study's retraction.

In a letter to the international Society of Toxicology (SOT), the Environmental Working Group (EWG) documents how Dr. Dennis Paustenbach directed a scheme to distort the findings of a Chinese study linking chromium-6 in drinking water with an increase in stomach cancer, then publish a paper under the byline of the original researcher, refuting the original findings. Paustenbach's San Francisco-based firm, ChemRisk, was working for Pacific Gas & Electric Co. in the infamous "Erin Brockovich" case, but concealed its role and the utility's funding.

"Dr. Paustenbach has failed to conduct himself with integrity, has failed to be honest and truthful in reporting and communicating his research, has hidden clear material conflicts of interest, and has failed to avoid situations that imply a conflict of interest"—all violations of specific articles of the Society of Toxicology's published Code of Ethics, said the letter from EWG Senior Vice President Richard Wiles. The letter is available at

The peer-reviewed Journal of Occupational and Environmental Medicine, which published the fraudulent study in 1997, is running a retraction in its current issue. Dr. Paul Brandt-Rauf, editor, writes that the article "failed to meet the journal's published editorial policy ... [F]inancial and intellectual input to the paper by outside parties was not disclosed." The journal was alerted to the fraud by an Environmental Working Group investigation published in December 2005.

EWG uncovered and published documents from California state scientists and the Brockovich court record that showed how ChemRisk tampered with the data reported by Dr. JianDong Zhang in 1987, which showed elevated rates of stomach cancer in Chinese villagers whose water was contaminated with chromium-6. ( The documents show that ChemRisk scientists rewrote Zhang's study to cast doubt on the cancer-chromium link, then submitted it under his name—and over his written objection. Zhang, who was paid $2,500 for his original data, has since died.

ChemRisk was helping PG&E fight a lawsuit by residents of Hinkley, Calif., for dumping chromium in their drinking water, that the utility eventually settled for $333 million. But the fraudulent article had a wider effect, influencing both state and federal regulations on chromium in drinking water. Paustenbach, whose firm holds federal contracts with the Department of Energy and the Centers for Disease Control, has a long record of consulting and testifying on behalf of major industrial polluters including PG&E, ExxonMobil and Dow Chemical.

"By concealing the funding source," Wiles wrote to the Society of Toxicology, "Paustenbach was able to use this study to weaken public health protections for chromium, a strategy that would not have been possible had the client that paid for the study been properly disclosed. PaustenbachÕs calculated deception was designed to benefit a client at the expense of millions of people with chromium-contaminated tap water.... In order to preserve the integrity of SOT as an organization with high ethical standards, we urge you to investigate the matter, and to censure Dr. Paustenbach."

The Society of Toxicology ( is "a professional and scholarly organization of scientists from academic institutions, government, and industry representing the great variety of scientists who practice toxicology in the U.S. and abroad." According to his online resume (, Paustenbach, who holds a Ph.D. in environmental toxicology from Purdue University, has received numerous awards from the Society.


Letter to the Society of Toxicology


EWG is a nonprofit research organization based in Washington, D.C., that uses the power of information to protect human health and the environment.