# 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 engineering firm. Paustenbach’s group risk methods to characterize occupational and environmental health hazards. 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. He was, for about 4 years, 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 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 and education

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. He joined Eli Lilly and Company as an engineer and industrial hygienist. After working at Eli Lilly, a pharmaceutical firm, for two years, he decided he needed an advanced degree. He took an educational leave and enrolled at University of Michigan to pursue an MS in Industrial Hygiene and Toxicology, which he completed in 1977. He returned to Eli Lilly. He took another educational leave 3 years later and then earned a PhD in environmental toxicology from Purdue University in 1982. While studying for his PhD, he founded the undergraduate/graduate programs in industrial hygiene at Purdue where he taught industrial hygiene, environmental epidemiology and industrial toxicology. After his PhD, he became the head of risk assessment at Stauffer Chemical in Westport, Connecticut.

## Career

Paustenbach twice started the environmental consulting firm, ChemRisk. The firm applied the principles of health risk assessment to quantitatively characterize the risk to humans of chemicals in foods, water, air, sediment, soil, and consumer products. 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.

## Professor

Paustenbach has served as an adjunct professor at seven universities. Specifically, 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.

## Philanthropy

In recent years, Paustenbach was involved in fundraising for Bellarmine College Preparatory, The Sacred Heart Schools, Purdue University, The University of Michigan, The Jackson Laboratory for Genomic Medicine, 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).

## 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