title: Modeling tribal exposures to methyl mercury from fish consumption.
abstract: Exposure assessment and risk management considerations for tribal fish consumption are different than for the general U.S. population because of higher fish intake from subsistence fishing and/or from unique cultural practices. This research summarizes analyses of available data and methodologies for estimating tribal fish consumption exposures to methyl mercury (MeHg). Large MeHg fish tissue data sets from the Environmental Protections Agency's (EPA's) Office of Water, USGS's EMMMA program, and other data sources, were integrated, analyzed, and combined with fish intake (consumption) data for exposure analyses using EPA's SHEDS-Dietary model. Results were mapped with GIS tools to depict spatial distributions of the MeHg in fish tissues and fish consumption exposure patterns. Contribution analyses indicates the major sources for those exposures, such as type and length of fish, geographical distribution (water bodies), and dietary exposure patterns. Sensitivity analyses identify the key variables and exposure pathways. Our results show that MeHg exposure of tribal populations from fish are about 3 to 10 times higher than the US general population and that exposure poses potential health risks. The estimated risks would be reduced as much as 50%, especially for high percentiles, just by avoiding consumption of fish species with higher MeHg concentrations such as walleye and bowfin, even without changing total fish intake. These exposure assessment methods and tools can help inform decisions regarding meal sizes and frequency, types of fish and water bodies to avoid, and other factors to minimize exposures and potential health risks from contaminated fish on tribal lands.
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, 109 T.W. Alexander Drive, Research Triangle Park, NC 27709, United States. Electronic address: xue.jianping@epa.gov.
authors.forename: Jianping
authors.initials: J
authors.lastname: Xue
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, 109 T.W. Alexander Drive, Research Triangle Park, NC 27709, United States.
authors.forename: Valerie
authors.initials: V
authors.lastname: Zartarian
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Exposure Research Laboratory, 109 T.W. Alexander Drive, Research Triangle Park, NC 27709, United States.
authors.forename: Bruce
authors.initials: B
authors.lastname: Mintz
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, United States.
authors.forename: Marc
authors.initials: M
authors.lastname: Weber
authors.affiliation: U.S. Environmental Protection Agency, Office of Science Policy, United States.
authors.forename: Ken
authors.initials: K
authors.lastname: Bailey
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, Sustainable and Healthy Communities Research Program, United States.
authors.forename: Andrew
authors.initials: A
authors.lastname: Geller
mesh_terms: D000818:Animals; D004032:Diet / Q000706:statistics & numerical data; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005399:Fishes / Q000378:metabolism*; D005506:Food Contamination / Q000706:statistics & numerical data; D006801:Humans; D008767:Methylmercury Compounds / Q000378:metabolism*; D044382:Population Groups / Q000706:statistics & numerical data*; D014481:United States; D014484:United States Environmental Protection Agency; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical
keywords: Exposures; Fish consumption; Mercury; SHEDS-Dietary; Tribal