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Bernard Weiss, Ph.D.

Contact Information

Phone Numbers

Office: (585) 275-1736



Neurobiology and Behavior
Our brains, the ultimate product of millions of years of evolution, are what make us human. But over the past few decades, scientists have discovered that many chemicals in our environment threaten the integrity of our brains. Thousands more have never been studied for their effects. We know some of the outcomes: reduced intelligence and cognitive function, increased antisocial tendencies, impaired senory and motor function, and elevated risks of neurodegenerative disorders such as Parkinson's disease.

Most of these chemicals are ubiquitous and persistent. We are exposed throughout our lifetimes. But some periods of life are more vulnerable than others. Early development is an especially perilous time for exposure to toxic chemicals. The brain is exquisitely sensitive during this period because of the many paths by which it expands and differentiates on the path to maturity. Cells divide and proliferate; they migrate to specific target areas; they grow connections to other cells to form massive neural networks; neurotransmitter systems take root. All these processes are candidates for interference by toxic chemicals. All are reflected in neurobehavioral outcomes that can be measured when organisms mature to a stage at which they can be tested by procedures that are sensitive to such interference. Late in life, we enter another period of enhanced vulnerability. We are not as able as during earlier periods to compensate for toxic processes and many of our organ systems operate at diminished capacity. It is also a period when these reduced capacities may begin to reflect the damage inflicted earlier in life.

My own research aims to relate behavioral measures to neurotoxicant exposure. Behavioral research occupies a special role in safety assessment because it offers the ability to trace changes in function as organisms mature and age. Among the endpoints of salient interest to regulatory agencies such as EPA and to chemical and pharmaceutical manufacturers are learning capacity, other aspects of cognitive capacity, motor and sensory performance, and differences between males and females.

My efforts have spanned a variety of agents: metals such as mercury and manganese; solvents such as toluene and methanol; air pollutants such as ozone; adventitious contaminants such as dioxin; and endocrine disruptors, which include common ingredients in consumer products such as phthalates.


Faculty Appointments


BA | New York University

PhD | University of Rochester


Distinguished Investigator Award, Neurotoxicology Specialty Section, Society of Toxicology

Stokinger Prize, American Conference of Governmental Industrial Hygienists

Scientist of the Year, Association of Children and Adults with Learning Disabilities

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Journal Articles

Evans SF, Kobrosly RW, Barrett ES, Thurston SW, Calafat AM, Weiss B, Stahlhut R, Yolton K, Swan SH. "Prenatal bisphenol A exposure and maternally reported behavior in boys and girls." Neurotoxicology.. 2014 Dec 0; 45:91-9. Epub 2014 Oct 13.

McCaffrey KA, Jones B, Mabrey N, Weiss B, Swan SH, Patisaul HB. "Sex specific impact of perinatal bisphenol A (BPA) exposure over a range of orally administered doses on rat hypothalamic sexual differentiation." Neurotoxicology.. 2013 May 0; 36:55-62. Epub 2013 Mar 13.

van Wijngaarden E, Thurston SW, Myers GJ, Strain JJ, Weiss B, Zarcone T, Watson GE, Zareba G, McSorley EM, Mulhern MS, Yeates AJ, Henderson J, Gedeon J, Shamlaye CF, Davidson PW. "Prenatal methyl mercury exposure in relation to neurodevelopment and behavior at 19 years of age in the Seychelles Child Development Study." Neurotoxicology and teratology.. 2013 39:19-25. Epub 2013 Jun 14.

Books & Chapters

Chapter Title: Psychological Indices of Toxicity
Book Title: Encyclopedia of Toxicology, 3rd Edition
Author List: Bernard Weiss
Edited By: Wexler, P., ed.
Published By: Elsevier2014

Book Title: Aging and Vulnerability to Environmental Chemicals
Author List: Bernard Weiss (editor)
Published By: Royal Society of Chemistry2013 in London

Book Title: The Alzheimer President
Author List: Bernard Weiss
Published By: Healthy World Press2011 in Seattle, WA




Pesticides: What We Don't Know