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Aisha Rivera Margarin, MD, MS

Program Director, Occupational & Environmental Medicine Residency
Faculty Associate, Environmental Health and Engineering
Johns Hopkins Bloomberg School of Public Health

Originally from Puerto Rico, Dr. Rivera is bilingual and board certified in occupational and general preventive medicine. As Program Director, she is responsible for organizing training and educational experiences, evaluating and mentoring residents and maintaining the residency's ACGME accreditation through a number of reporting and administrative tasks. She serves as a Medical Advisor to the International Association of Fire Fighters through a longstanding relationship between the union and the residency program and is the course director for the Department of Environmental Health and Engineering's Clinical Occupational and Environmental Toxicology Course. As of February 2019, she oversees the growing premed focus area for the Master of Health Sciences offered by the Department of Environmental Health and Engineering. Outside of JHSPH, she maintains various professional relationships including working as a per diem physician with Concentra where she was most recently providing medical director and providing oversight for an onsite clinic, is a credentialed Clinical Peer Reviewer for several private companies, and has been assisting the NYC MTA with reviewing their practices in response to COVID-19 pandemic. ​

Her professional interests include: mentoring students and residents, medical education, firefighter health and safety, healthcare worker health, exploring the link between workplace culture and worker well-being, systems thinking, women in the workplace, vulnerable populations, work as a social determinant of health, workplace policies that promote healthy families, and international occupational health. She is a member of the American College of Occupational and Environmental Medicine and serves on the Presidential Taskforce to Increase OEM Visibility. Her hobbies and interests include dedicating time to faith, family, and friends; eating good food; hearing good comedy; listening to podcasts and Audible books and music; traveling; home décor; and keeping up with current events/news.

Brian S. Schwartz, MD, MS

Deputy Program Director, Occupational and Environmental Medicine Residency
Professor and Associate Chair, Department of Environmental Health and Engineering
Johns Hopkins Bloomberg School of Public Health

Dr. Brian Schwartz is a professor, physician, and environmental epidemiologist investigating a broad range of environmental exposures and diseases, from specific toxicants like lead and other metals, to newer concerns such as the environmental health consequences of climate change, food production, and unconventional natural gas development. Much of his research is part of his work as Director of the Environmental Health Institute at the Geisinger Center for Health Research in Danville, PA. There he has become increasingly interested in using electronic health records for “big data” epidemiology. He and his team have ongoing or developing studies of the built environment and obesity, with particular emphasis on the land use, local food, local physical activity, and social environments; the public health impacts of Marcellus shale development in Pennsylvania; the community health effects of animal feeding operations, including the risk of methicillin-resistant Staphylococcus aureus (MRSA); the built environment, abandoned coal mine lands, and diabetes mellitus progression; the contribution of abandoned mine lands to community health and contextual effects; and evaluating the public health risks of energy scarcity and changing energy choices. As the co-director of the Program on Global Sustainability and Health, we are developing courses and research related to these areas.

He is the principal investigator for a number of grants including the surveillance program of former workers of Los Alamos National Laboratories in New Mexico. Each resident typically has an opportunity to travel and participate in surveillance exams of former workers of Los Alamos and Sandia National Laboratories during their residency experience.