Dennis Paustenbach

Dennis J. Paustenbach PhD, CIH, DABT, (born Oct 29, 1952) is an American scientist, businessman, researcher, and author. Dennis is the senior scientist and head of the risk assessment group at TRC Companies, which is an international consulting, engineering, and construction management firm. He is the founder and former president of ChemRisk, a consulting firm specializing in the use of toxicology, exposure science, epidemiology, and health physics to characterize the hazards of chemicals in soil, air, water, food, sediments and consumer products. For about 4 years, Paustenbach was a Group Vice-President at Exponent, a publicly traded consulting firm.

Paustenbach has published approximately 320 peer-reviewed papers in scientific journals, about 55 book chapters, and has presented nearly 350 papers at various scientific conferences during his career. His widely read textbook on health risk assessment is in its third edition (issued June 2024). He has given expert testimony in many courts, often on behalf of corporations being sued, regarding the health hazards posed by dioxins, talc, asbestos, benzene, lead, chromium, beryllium, formaldehyde, carbon monoxide, cobalt, chlorinated solvents, kratom (and other herbals), PFAS chemicals, food additives, and other chemicals.

Early life, education, and work

Paustenbach was born in Tarentum, Pennsylvania (a Pittsburgh suburb) in 1952. He left his hometown after first grade and moved to Akron, Ohio, where he attended St. Matthews. His family later moved to Strasburg, Ohio, which was in a rural setting adjacent to many Amish communities, where he graduated from high school.

In 1974, Paustenbach graduated from the Rose Polytechnic Institute with a BS in Chemical Engineering (now Rose-Hulman Institute) where he was a Kemper Scholar.

Paustenbach worked at Eli Lilly and Company, a pharmaceutical firm, as a process engineer for two years. Paustenbach earned a master's degree in Industrial Hygiene and Toxicology from University of Michigan in 1977. In 1987, ChemRisk became a joint venture with McLaren Engineering. ChemRisk grew to have about 125 persons in 10 locations in the U.S. and Australia between 1987-1995. In 1993, Paustenbach was selected to be the president and CEO of McLaren-Hart Environmental Engineering, a national firm with 15 offices and 600 employees. He was the youngest CEO of a major engineering firm in this industry.

In the 1980s and 1990s, Paustenbach conducted research into the dioxins and furans. Among his first major undertakings was characterizing the health hazards posed by dioxin contaminated soil including the site in Times Beach, Missouri and 37 other related sites. In the 1990s, he conducted research evaluating the hazards posed by occupational exposure to pharmaceuticals, benzene, nitrosamines, beryllium, and formaldehyde. Also, in the 1990s, he published many studies which evaluated the exposure and health hazards associated with exposure to hexavalent chromium which were pertinent to Hinkley, CA and Hudson County, NJ. He was the lead scientist in conducting dose-reconstructions at several nuclear arsenals: Rocky Flats, Los Alamos, Oak Ridge, and Hanford (the largest assessments ever conducted). From about 2000 to 2024, he performed more than 1,000 risk assessments on many different topics including asbestos exposure of auto mechanics and tradesmen, benzene exposure in refineries, lead in consumer products, arsenic in wine, perfluorinated chemicals in groundwater, MCHM in drinking water, hydrocarbons in drinking water, and PFAS in drinking water. Paustenbach and colleagues developed many of the earliest guidelines for identifying safe levels of exposure in the workplace and multi-pathway exposure assessment methods. Later, he conducted research involving the release of cobalt and chromium from medical devices. ChemRisk was sold to Cardno Engineering of Australia in 2014.

In April 2019, Dennis founded and became president of Paustenbach and Associates. The consulting firm had 3 offices, 19 full-time professionals, and several “at will” professionals. In August 2024, the firm was purchased by TRC, an engineering firm, and Paustenbach became a risk assessment group leader and chief scientist.

Teaching Paustenbach has worked as an adjunct professor at seven universities: the University of Texas (Houston), Purdue University, University of Bridgeport, University of Massachusetts (Amherst), University of California at Irvine School of Medicine (clinical professor of Occupational Medicine), University of Michigan (Ann Arbor) and, currently, the University of Kansas Medical School (Kansas City).

He was awarded an honorary Doctor of Science degree from Purdue University in 2006 and a Doctor of Engineering from the Rose-Hulman Institute of Technology in 2007.

Books The Risk Assessment of Environmental and Human Health Hazards: A Textbook of Case Studies (1989) Human and Ecological Risk Assessment: Theory and Practice (2002).

Awards and honors 1992 - Howard Kusnetz Award 1997 - Outstanding Risk Practitioner by the Society for Risk Analysis 2002 - Arnold Lehman Award by Society of Toxicology 2009 - Fellow of the American Industrial Hygiene Association 2010 - Henry Smyth Award for Contributions in Toxicology by American Conference of Governmental Industrial Hygienists 2010 - Ed Baier Award by the American Industrial Hygiene Association 2011 - Fellow of the Society for Risk Analysis 2015 - Outstanding graduate of the School of Health Sciences. 2016 – Best Published Paper on Medical Devices by Society of Toxicology 2024 – Shubik Award for outstanding contribution to toxicology by the Toxicology Forum

Industry consulting

Chromium Paustenbach and his consulting firms have "drawn the scrutiny of investigative journalists." Paustenbach testified that PG&E paid ChemRick about $1.5 million for litigation support.

In 1996, Paustenbach suggested that the Chrome Coalition, the chromium industry's trade group at the time, should fill a "data gap" to forestall rulemaking so that OSHA does not reduce the allowable amount of chromium dust in workplaces.

Paustenbach was at the center of a publishing scandal involving the research of Chinese scientist Jian Dong Zhang. In 2005, the Wall Street Journal ran a front-page story questioning the role of Paustenbach and his company ChemRisk amidst litigation regarding Hinkley groundwater contamination, on which the movie Erin Brockovich was based.

Zhang's 1987 study reported an association between chromium pollution of drinking water and higher rates of stomach cancer in residents of three villages in Liaoning Province (in rural northeastern China) who lived near a chromium-ore smelter and drank tainted water for years. The study linked chromium-contaminated groundwater with a range of public-health illnesses.

In 2006, after the Wall Street Journal article, the Zhang study was retracted by the Journal of Occupational and Environmental Medicine. The Journal conducted a six-month internal review of the previous 1997 retraction, starting that:"It has been brought to our attention that an article published in JOEM in the April 1997 issue by Zhang and Li failed to meet the journal's published editorial policy in effect at that time ... Specifically, financial and intellectual input to the paper by outside parties was not disclosed." The retraction was written by JOEM editor Paul Brandt-Rauf. Although Zhang had died by the time the JOEM made its investigation, his co-author agreed that the revised paper should be retracted. Environmental groups such as the Environmental Working Group have since sought to have Paustenbach censured by the Society of Toxicology.

According to Allan Hirsch, CalEPA's 2008 review of Zhang's original 1987 paper agreed with his findings that the rates of stomach cancer in the three villages were significantly higher than those in the province.

One of Paustenbach's textbooks claimed that he helped save industry hundreds of millions of dollars in cleanup costs for chromium pollution in New Jersey. From 2002 to 2012, he had published 18 papers on asbestos, was "frequently retained as an expert by automotive manufacturers," and had testified on their behalf.

In 2006, Paustenbach spoke at a Canadian Chrysotile Institute conference (formerly the Asbestos Institute) about "dose-reconstruction" studies and their utility in asbestos litigation, explaining that a corporation hiring a consulting firm to complete a $250,000 to $500,000 study was a "drop in the bucket" compared to the $4 million it costs to defend a case at trial.

In 2016, the Center for Public Integrity published an investigation that highlighted Paustenbach’s work for Ford Motor Company to downplay the dangers of asbestos in car brake pads. Among other concerns, ADAO noted that:"Dr. Paustenbach has a long history of involvement with industries that have a vested interest in the continued use of asbestos. His prior affiliations and consulting work for chemical and environmental risk assessment firms, as well as his association with the Essential Minerals Association, American Chemistry Council, and other industry groups, raise concerns about potential conflicts of interest that could compromise the integrity of the peer review process." The article also noted Paustenbach's work on behalf of tobacco industry lawyers. Peninsula Bridge of Menlo Park (California), The Roux Institute for AI and Genomic Medicine (Maine), The Alan Alda Center for Communicating Science at Stony Brook University, Indiana Landmarks, the Mayo Clinic, the Enfield Shaker Village/Museum (New Hampshire) and The Shakers of Sabbathday Lake (Maine).