EPA researchers collected data on a variety of at-risk demographic groups in New York City to determine who has the greatest risk of exposure to mercury. Data was analyzed using a geographic information system tool that enabled the scientists to identify areas and populations in most need of outreach. The resulting geographical information system (GIS) targeting tool identifies areas and populations most in need of outreach based on their exposure to certain fish and shellfish. The tool is being shared with the Pediatric Environmental Health Specialty Unit (PEHSU) at New Yorks Mt. Sinai School of Medicine, as well as the States of New York and New Jersey, to develop a strategy for sharing these results with pediatricians and ob/gyns in affected areas.