PROJECT SUMMARY With concerns about human exposure to per- and polyfluoroalkyl substances (PFASs) on the rise, regional data about PFASs in various environmental media are needed to inform enforceable and protective standards for common routes of exposure, including seafood consumption. PFASs are persistent environmental contaminants of particular concern for vulnerable and sensitive populations, including children and pregnant women. Four PFASs are commonly detected in blood from United States (US) residents: perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), perfluorononanoic acid (PFNA), and perfluorohexane sulfonic acid (PFHxS). Animal and epidemiologic studies support a role for PFAS effects on the thyroid, liver, cholesterol, and even cancer risk. Human exposure to PFASs occurs primarily through ingestion, notably via PFAS contaminated drinking water and diet. These contaminants pose a regional as well as national threat to surface water and drinking water supplies with detections occurring in 49 states. PFASs in fish and shellfish, particularly in freshwater ecosystems, are recognized as an important dietary source of exposure, but data regarding exposures from marine sourced seafood are limited, hindering the development of health protective standards. In the northeastern United States (US), where an abundance of PFAS contamination sites have been identified and seafood consumption rates tend to be high relative to other regions of the US, marine species comprise a considerable share of the market. In New Hampshire (NH), the PFAS landscape is rapidly evolving with implementation of regulatory limits on drinking water supplies, investigation and remediation efforts at affected sites, and ongoing efforts to monitor exposed communities. As regulations of PFAS use evolve and remediation commences at contaminated sites, seafood monitoring will be integral to evaluating effectiveness of policies and remediation activities. There is an urgent need to collect human exposure data in order to provide critical information to understand the PFAS exposure-health outcome relationship. The proposed research encompasses both measurements of PFASs in regionally sourced, commonly consumed marine seafood species, and an assessment of local seafood consumption habits to help meet this need. The research will be conducted by a highly interdisciplinary team of scientists (marine biologists, epidemiologists, toxicologists, environmental chemists) involving a collaboration between the NH Department of Environmental Services and Dartmouth College. The project will leverage a unique archive of existing fish and shellfish tissue samples harvested throughout the Gulf of Maine (GOM), as well as new samples collected in Great Bay (GB) adjacent to a PFAS contamination site at the Pease Air Force Base. Furthermore, the proposed research will take advantage of the start of active PFAS remediation at the Pease Air Force Base to evaluate remedial effectiveness based on PFAS concentrations in the neighboring GB. The research project is proposed to provide time critical data to support timely action to protect public health in the GOM region.

PROJECT NARRATIVE Efforts to reduce the population burden of perfluoroalkyl substances (PFASs) are urgently needed due to their common presence in our environment and known adverse effects on human health. Since seafood is known to be an important PFAS exposure pathway for humans, investigations of PFAS concentrations in marine- sourced seafood and New Hampshire residents’ seafood consumption patterns will inform PFAS exposure reduction policies across New England aimed at establishing surface water standards and seafood consumption advisories. Investigating changes in PFAS concentrations in shellfish near highly contaminated sites will provide critical information about how newly implemented groundwater remediation systems are addressing PFAS bioaccumulation in commercially- and recreationally-important shellfish beds in the vicinity.