Megan A. Arnold, Ph.D.

Senior Scientist
Health Sciences
  • CV (English)
  • Contact Card

Dr. Arnold is a toxicologist with expertise in the evaluation of chemical exposures and their impacts on human health. This includes toxicological risk assessments of extractable and leachable substances from medical devices and consumer products. Dr. Arnold has over a decade’s experience with cognitive and behavioral assays used to evaluate rodent models of neurodevelopmental disorders. Her research background is in developmental neurotoxicity of metals, chemotherapeutics, maternal immune response, and maternal diet. She also has familiarity evaluating epidemiology studies related to metals, perfluorinated chemicals, biopersistent fibers, and herbicides.

Prior to joining Exponent, Dr. Arnold held the position of Associate Toxicologist at Gradient, providing human health risk assessment consulting services from 2019 until 2021. Dr. Arnold earned her Ph.D. in Cognitive and Behavioral Sciences from Auburn University in 2020. Her doctoral work focused on developmental exposures and effects on neuromotor, learning, and memory in adult offspring. Her thesis work compared the effects of acute and chronic maternal immune activation during gestation on intradimensional shifts, extradimensional set-shifting, and working memory in adult offspring and attenuation by an immunomodulatory compound. In addition, she has served as instructor and provided teaching support for courses including psychopharmacology, research methods in social sciences, and psychology of learning at Auburn University and Harvard University.


  • Ph.D., Cognitive and Behavioral Sciences, Auburn University, 2020
  • M.S., Psychology, Auburn University, 2016
  • B.S., Psychology, James Madison University, 2012


Kendricks, D.R., Boomhower, S.R., Arnold, M.A., Glenn, D.J., Newland, M.C. (2020). Adolescent methylmercury exposure alters short-term remembering, but not sustained attention, in male Long-Evans rats. Neurotoxicology 78:186–194.

Arnold, M.A., Newland, M.C. (2018). Variable behavior and repeated learning in two mouse strains: Developmental and genetic contributions. Behavioural Processes 157:509–518.

Shen, A.N., Cummings, C., Hoffman, D., Pope, D., Arnold, M.A., Newland M.C. (2016). Aging motor function, and sensitivity to calcium channel blockers: an investigation using chronic methylmercury exposure. Behavioural Brain Research315:103–114.


Arnold, M.A., Sauer, R.A., Newland, M.C. (2018, March). Doxorubicin-induced neuromotor impairments in male athymic NCr Mice: Partial protection by phenylaminoethyl selenide. Poster presented at the meeting of Society of Toxicology, San Antonio, TX.

Arnold, M.A., Newland, M.C. (2015, October). Baseline-dependent effects of d-amphetamine on operant variations: A strain comparison. Poster presented at the meeting of the Southeastern Association for Behavior Analysis, Roanoke, VA.

Arnold, M.A., Boomhower, S.R., Newland, M.C. (2015, April). Gestational exposure to high-fat diet and polyinosinic:polycytidylic acid in mice: Effects on spatial and visual discrimination. Seminar presented at Auburn University’s Student Symposium, Auburn, AL.

Prior Experience

Associate Toxicologist, Gradient, 2019–2021

Academic Appointments

Teaching Support, Faculty of Arts and Sciences, Harvard University, 2020–2021

Professional Affiliations

Society of Toxicology (SOT), 2015–present

Society for Neuroscience (SFN), 2014

Project Experience

Dermal Assessments

Performed chemical hazard assessments and quantitative risk assessments for skin sensitization and irritation after potential exposure to constituents of various consumer products designed for limited contact with skin. Identified potential chemicals of concern and established exposure levels intended to protect consumers from adverse skin reactions.

Medical Device Extractables

Performed toxicological risk assessments for extractable and leachable substances from medical devices.

Systematic Literature Reviews

Performed systematic reviews of the epidemiological and experimental animal literature assessing developmental, neurodevelopmental, immune, cognitive, and behavioral effects for a variety of exposures including paraquat, perfluorinated chemicals, polychlorinated biphenyls (PCBs), metals, and industrial solvents.

News & Events


  • Ph.D., Cognitive and Behavioral Sciences, Auburn University, 2020
  • M.S., Psychology, Auburn University, 2016
  • B.S., Psychology, James Madison University, 2012