title: Assessing potential health risks to fish and humans using mercury concentrations in inland fish from across western Canada and the United States.
abstract: Fish represent high quality protein and nutrient sources, but Hg contamination is ubiquitous in aquatic ecosystems and can pose health risks to fish and their consumers. Potential health risks posed to fish and humans by Hg contamination in fish were assessed in western Canada and the United States. A large compilation of inland fish Hg concentrations was evaluated in terms of potential health risk to the fish themselves, health risk to predatory fish that consume Hg contaminated fish, and to humans that consume Hg contaminated fish. The probability that a fish collected from a given location would exceed a Hg concentration benchmark relevant to a health risk was calculated. These exceedance probabilities and their associated uncertainties were characterized for fish of multiple size classes at multiple health-relevant benchmarks. The approach was novel and allowed for the assessment of the potential for deleterious health effects in fish and humans associated with Hg contamination in fish across this broad study area. Exceedance probabilities were relatively common at low Hg concentration benchmarks, particularly for fish in larger size classes. Specifically, median exceedances for the largest size classes of fish evaluated at the lowest Hg concentration benchmarks were 0.73 (potential health risks to fish themselves), 0.90 (potential health risk to predatory fish that consume Hg contaminated fish), and 0.97 (potential for restricted fish consumption by humans), but diminished to essentially zero at the highest benchmarks and smallest fish size classes. Exceedances of benchmarks are likely to have deleterious health effects on fish and limit recommended amounts of fish humans consume in western Canada and the United States. Results presented here are not intended to subvert or replace local fish Hg data or consumption advice, but provide a basis for identifying areas of potential health risk and developing more focused future research and monitoring efforts.
authors.affiliation: Colorado Parks and Wildlife, 317 West Prospect Rd., Fort Collins, CO 80526, United States. Electronic address: Salvelinus2005@gmail.com.
authors.forename: Jesse M
authors.initials: JM
authors.lastname: Lepak
authors.affiliation: U.S. Geological Survey, Colorado Cooperative Fish and Wildlife Research Unit, Department of Fish, Wildlife, and Conservation Biology, Department of Statistics, Colorado State University, 1484 Campus Delivery, Fort Collins, CO 80523, United States. Electronic address: mevin.hooten@colostate.edu.
authors.forename: Mevin B
authors.initials: MB
authors.lastname: Hooten
authors.affiliation: U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331, United States. Electronic address: ceagles-smith@usgs.gov.
authors.forename: Collin A
authors.initials: CA
authors.lastname: Eagles-Smith
authors.affiliation: U.S. Geological Survey, Wisconsin Water Science Center, 8505 Research Way, Middleton, WI 53562, United States. Electronic address: mttate@usgs.gov.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Tate
authors.affiliation: U.S. Geological Survey, Wisconsin Water Science Center, 8505 Research Way, Middleton, WI 53562, United States. Electronic address: malutz@usgs.gov.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Lutz
authors.affiliation: U.S. Geological Survey, Dixon Field Station, 800 Business Park Drive, Dixon, CA 95620, United States. Electronic address: jackerman@usgs.gov.
authors.forename: Joshua T
authors.initials: JT
authors.lastname: Ackerman
authors.affiliation: U.S. Geological Survey, Forest and Rangeland Ecosystem Science Center, 3200 SW Jefferson Way, Corvallis, OR 97331, United States. Electronic address: jwillacker@usgs.gov.
authors.forename: James J
authors.initials: JJ
authors.lastname: Willacker
authors.affiliation: Oregon State University, Department of Fisheries and Wildlife, 104 Nash Hall, Corvallis, OR 97331, United States. Electronic address: allyson.jackson@oregonstate.edu.
authors.forename: Allyson K
authors.initials: AK
authors.lastname: Jackson
authors.affiliation: Biodiversity Research Institute, 276 Canco Road, Portland, ME 04103, United States. Electronic address: david.evers@briloon.org.
authors.forename: David C
authors.initials: DC
authors.lastname: Evers
authors.affiliation: University of Wisconsin La Crosse, River Studies Center, 1725 State Street, La Crosse, WI 54601, United States. Electronic address: jwiener@uwlax.edu.
authors.forename: James G
authors.initials: JG
authors.lastname: Wiener
authors.affiliation: National Park Service, Air Resources Division, PO Box 25287, Denver, CO 80225, United States. Electronic address: colleen_flanagan_pritz@nps.gov.
authors.forename: Colleen Flanagan
authors.initials: CF
authors.lastname: Pritz
authors.affiliation: San Francisco Estuary Institute, 4911 Central Ave, Richmond, CA 94804, United States. Electronic address: jay@sfei.org.
authors.forename: Jay
authors.initials: J
authors.lastname: Davis
mesh_terms: D000818:Animals; D002170:Canada; D004784:Environmental Monitoring / Q000379:methods*; D005260:Female; D005399:Fishes / Q000378:metabolism*; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D008297:Male; D008628:Mercury / Q000032:analysis*; D018570:Risk Assessment / Q000379:methods; D014481:United States; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Advisory development; Benchmark; Consumption advice; Hierarchical modeling; Monitoring; Size class; Uncertainty