Tomas R. Guilarte, PhD is professor of neurotoxicology in the Divisions of Toxicological Sciences and Radiation Health Sciences in the Department of Environmental Health Sciences at the Johns Hopkins University Bloomberg School of Public Health. He also holds a joint appointment in the division of Human Nutrition in the Department of International Health. Dr. Guilarte received Bachelors (1974) and Masters of Science (1976) degrees from the University of Florida and doctoral degree (1980) in environmental health sciences from the Johns Hopkins University School of Hygiene and Public Health (now named Johns Hopkins University Bloomberg School of Public Health). He has spent his entire academic career at Johns Hopkins and was promoted to full professor with tenure in 1994. Dr. Guilarte was President (2000) of the Neurotoxicology Specialty Section of the Society of Toxicology. He has served in numerous scientific advisory panels and boards including the National Center for Toxicological Research of the Food and Drug Administration. He is currently a member of the Environmental Health Review Committee for the National Institute of Environmental Health Sciences. He is associate editor of the journal NeuroToxicology and is in the editorial board of Toxicology and Applied Pharmacology. Dr. Guilarte has been a member of several NIH study sections and he reviews for several scientific journals. Research Interests Dr. Guilarte's current research interests are in the area of neurotoxicology/neuroscience and brain imaging. His laboratory is elucidating the central nervous system (CNS) effects produced by exposure to low levels of lead (Pb2+) during development, and the role of the NMDA subtype of glutamate receptors. The research focuses on the molecular and cellular mechanisms by which Pb2+ produces impairments in cognitive function using multidisciplinary approaches. His laboratory is also interested in assessing intervention strategies that can ameliorate or modify the effects of developmental Pb2+ exposure on cognitive function. In this regard, his research has recently shown that environmental enrichment reverses the cognitive and molecular deficits induced by exposure to Pb2+ during early development. A second major focus of research in his laboratory is to validate and apply an in vivo biomarker of brain injury that is applicable to assess the effects of environmental chemicals on the brain as well as to assess the onset and progression of neurodegenerative diseases. This research is focused in understanding and measuring the response of a glial protein, the peripheral benzodiazepine receptor (PBR). The PBR is exclusively expressed in glial cells in the brain making it a biomarker of gliosis and indirectly of brain injury. His work has demonstrated that following neurotoxicant-exposure in experimental animals this protein is selectively increased in brain regions that are damaged. The goal is to use this biomarker in human studies since the PBR response to brain injury can be monitored using non-invasive imaging techniques such as Positron Emission Tomography (PET). Dr. Guilarte's laboratory is also examining the effects of chronic low-level manganese exposure on the CNS. Manganese has recently been approved for use in gasoline and exposure to high levels of manganese results in a Parkinsonian-like syndrome. However, the CNS effects of chronic low-level exposures are not known. In this regard, he is also interested in the interaction(s) between environmental and genetic factors in the etiology of Parkinson's disease.