Pamela Lein, PhD is a neurotoxicologist and developmental neurobiologist who studies the interaction between genes and environment that can lead to a variety of complex disorders from asthma to autism and Alzheimer’s.

Dr. Lein’s work focuses on the way environmental stressors like pesticides and near-roadway exposures—which include car exhaust and particles from tire wear and tear—can both change the structure of nerve cells and disrupt how they communicate with each other and with other tissues throughout the body.

Using an array of experimental models and techniques, from primary neuronal cell cultures, zebrafish and rodents, to cellular and molecular testing, in vivo imaging and behavioral studies, Dr. Lein’s groundbreaking research has influenced state and federal policy on the hazards chemicals pose to human health. Through Tox21, her work also contributes to ongoing international efforts identifying the chemicals most likely to negatively affect human health and development.

Dr. Lein’s pioneering research includes:

• Discovering that bone morphogenetic proteins stimulate increased branching in neurons, which controls how many connections they can receive from cells upstream in the neural circuit. Scientists believe that this type of growth may contribute to learning and memory and have found that inappropriate branching (either too much or too little) accompanies behavioral problems, while promoting dendritic growth may help the brain recover from ischemic stroke.
• Providing the first evidence that polychlorinated biphenyls (PCBs), a class of environmental contaminants already shown to interfere with human neurodevelopment, modulate specific signaling pathways and processes in neurodevelopment that are altered in people with neurodevelopmental disorders. This work suggests PCBs may have a causal link with receptors and developmental problems like autism and attention-deficit hyperactivity disorder.
• Proving that the organophosphorus pesticide, chlorpyrifos, interferes with the nervous system that regulates the airways to cause asthma symptoms at levels significantly below those allowed for pest control, a discovery that has influenced changes in state and federal public health policy.
• Demonstrating that persistent organic pollutants have a distinct, toxic effect on neurons by boosting or curbing their growth.
• Identifying PCB 11, which is ubiquitous in pigments sold in the US, as well as in water, air, and the food chain, as potentially harmful to the developing brain.  Scientists now screen for PCB 11, to better understand its neurotoxicity.
• Showing that exposure of rodents to real-world traffic-related air pollution (TRAP) alters the way the brain develops, and may speed up the deterioration that Alzheimer’s Disease causes.

Over the years, Dr. Lein has sat on the editorial boards of a number of peer-reviewed journals and been a member of various scientific programs and committees. Her appointments include:

• Editor-in-Chief, NeuroToxicology
• Editorial Board, Chemical Research in Toxicology
• Editorial Board, Current Research in Toxicology
• Editorial Board, Toxics
• Chair, Society of Toxicology Education and Career Development Committee
• Expert Author, USEPA IRIS Assessment of PCBs
• Scientific Advisor, ENDpoiNTS, EU research consortium, European H2020 EDC Program, Utrecht University, Utrecht, Netherlands
• Member, Committee to Review Report on Long-Term Health Effects on Army Test Subjects National Academies of Sciences, Engineering and Medicine
• Member, NIH CounterACT Program Steering Committee
• Member, Scientific Advisory Panel, U.S. Environmental Protection Agency (USEPA)
• Member, External Advisory Committee, NIEHS Core Center, University of Rochester, NY
• Member, External Advisory Committee, NIEHS T32 Training Program, University of Illinois at Urbana-Champaign
• Member, External Advisory Board, NIA-funded Program Project Grant, “Urban Air Pollution and Alzheimer’s Disease: Risk, Heterogeneity and Mechanisms”, University of Southern California, Los Angeles, CA
• Member, Standing Committee to Advise the Department of State on Unexplained Health Effects on US Government Employees and Their Families at Overseas Embassies, The National Academies of Sciences, Engineering and Medicine
• Member, Committee for the Peer Review of the NTP Monograph on Systemic Review of Fluoride Exposure and Neurodevelopmental and Cognitive Health Effects, The National Academies of Sciences, Engineering, and Medicine
• Member, National Toxicology Program Board of Scientific Counselors
• Endowment Fund Steward, Society of Toxicology Neurotoxicology Specialty Section

Social Media

• Twitter

Positions at UC Davis

• Chair and Professor, Department of Molecular Biosciences, School of Veterinary Medicine
• Director, CounterACT Center of Excellence

Areas of Expertise

• Cellular and molecular neurobiology
• Developmental neurobiology
• Neuropharmacology
• Neurotoxicology
• Neuroinflammation

Major Research Papers

Pan, Shiyue & Bruun, Donald & Lein, Pamela & Chen, CY. (2024). Cardiovascular responses of adult male Sprague–Dawley rats following acute organophosphate intoxication and post-exposure treatment with midazolam with or without allopregnanolone. Archives of Toxicology. 1-13. 10.1007/s00204-023-03679 x. https://www.researchgate.net/publication/377928414_Cardiovascular_responses_of_adult_male_Sprague Dawley_rats_following_acute_organophosphate_intoxication_and_post-exposure_treatment_with_midazolam_with_or_without_allopregnanolone

Valerie A. Porter, Brad A. Hobson, Brent Foster, Pamela J. Lein, Abhijit J. Chaudhari,
Fully automated whole brain segmentation from rat MRI scans with a convolutional neural network,
Journal of Neuroscience Methods, Volume 405, 2024, 110078, ISSN 0165-0270, https://doi.org/10.1016/j.jneumeth.2024.110078

Andrew, Peter & Feng, Wei & Calsbeek, Jonas & Antrobus, Shane & Cherednychenko, Gennady & MacMahon, Jeremy & Bernardino, Pedro & Liu, Xiuzhen & Harvey, Danielle & Lein, Pamela & Pessah, Isaac. (2024). The alpha4 nicotinic acetylcholine receptor is necessary for the initiation of organophosphate-induced neuronal hyperexcitability. 10.1101/2024.01.24.576980. https://www.researchgate.net/publication/377730772_The_alpha4_nicotinic_acetylcholine_receptor_is_necessary_for_the_initiation_of_organophosphate-induced_neuronal_hyperexcitability

Muñoz, Maria & Lein, Pamela. (2024). Toxic textiles: Potential health risks associated with toxic chemicals in clothing. Open Access Government. 41. 384-385. 10.56367/OAG-041-9857. https://www.researchgate.net/publication/377670233_Toxic_textiles_Potential_health_risks_associated_with_toxic_chemicals_in_clothing

Sandoval, Simone & Malany, Keegan & Thongphanh, Krista & Martinez, Clarisa & Goodson, Michael & da Costa Souza, Felipe & Lin, Lo-Wei & Sweeney, Nicolle & Pennington, Jamie & Lein, Pamela & Kerkvliet, Nancy & Ehrlich, Allison. (2023). Activation of the aryl hydrocarbon receptor inhibits neuropilin-1 upregulation on IL-2-responding CD4+ T cells. Frontiers in Immunology. 14. 10.3389/fimmu.2023.1193535. https://www.researchgate.net/publication/375659888_Activation_of_the_aryl_hydrocarbon_receptor_inhibits_neuropilin-1_upregulation_on_IL-2-responding_CD4_T_cells