Dean Baker has more than 25 years of research experience in occupational and environmental epidemiology. The primary emphasis of his research has been on community-based epidemiological studies. During the past several years, he has focused on developmental toxicity and children's environmental health. He has conducted several epidemiological research studies examining chronic health effects of gestational and early childhood exposure to heavy metals and organochlorine chemicals. His other area of research has been on the health effects of psychosocial stressors in the workplace and in communities exposed to environmental hazards. In both of these areas, Dr. Baker has made contributions to… the epidemiological study design and methods. He was elected 3 times as Secretary-Treasurer of the International Society for Environmental Epidemiology, and was a founding member. He is an active teacher at the university, directing an occupational medicine residency program and supervising graduate students. Mark J Nieuwenhuijsen has been involved in various environmental exposure assessment, epidemiology, and health risk assessment studies in the Netherlands, the UK, Eastern Europe and the US. His interests include the health effects of chlorination by-products in water, traffic related air pollution and metals, specifically in relation to reproductive, respiratory, renal and cancer effects. He has published over a hundred papers. He graduated from Wageningen University, the Netherlands, and went to do a PhD at the National Heart and Lung Institute in London, UK. For his post doc he went to the University of California, Davis, USA after which he took up a faculty position at Imperial College London, UK. In January 2007 he joined the Center for Research in Environmental Epidemiology (CREAL) in Barcelona, Spain as a Research Professor. He is associate editor on the journals 'Occupational and Environmental Medicine' and the 'Journal of Exposure Science and Environmental Epidemiology'.Dean Baker has more than 25 years of research experience in occupational and environmental epidemiology. The primary emphasis of his research has been on community-based epidemiological studies. During the past several years, he has focused on developmental toxicity and children's environmental health. He has conducted several epidemiological research studies examining chronic health effects of gestational and early childhood exposure to heavy metals and organochlorine chemicals. His other area of research has been on the health effects of psychosocial stressors in the workplace and in communities exposed to environmental hazards. In both of these areas, Dr. Baker has made contributions to the epidemiological study design and methods. He was elected 3 times as Secretary-Treasurer of the International Society for Environmental Epidemiology, and was a founding member. He is an active teacher at the university, directing an occupational medicine residency program and supervising graduate students. Mark J Nieuwenhuijsen has been involved in various environmental exposure assessment, epidemiology, and health risk assessment studies in the Netherlands, the UK, Eastern Europe and the US. His interests include the health effects of chlorination by-products in water, traffic related air pollution and metals, specifically in relation to reproductive, respiratory, renal and cancer effects. He has published over a hundred papers. He graduated from Wageningen University, the Netherlands, and went to do a PhD at the National Heart and Lung Institute in London, UK. For his post doc he went to the University of California, Davis, USA after which he took up a faculty position at Imperial College London, UK. In January 2007 he joined the Center for Research in Environmental Epidemiology (CREAL) in Barcelona, Spain as a Research Professor. He is associate editor on the journals 'Occupational and Environmental Medicine' and the 'Journal of Exposure Science and Environmental Epidemiology'.