title: Fukushima derived radiocesium in subsistence-consumed northern fur seal and wild celery.
abstract: In July 2014, our investigative team traveled to St. Paul Island, Alaska to measure concentrations of radiocesium in wild-caught food products, primarily northern fur seal (Callorhinus ursinus). The 2011 Fukushima Daiichi Nuclear Power Plant accident released radiocesium into the atmosphere and into the western Pacific Ocean; other investigators have detected Fukushima-derived radionuclides in a variety of marine products harvested off the western coast of North America. We tested two subsistence-consumed food products from St. Paul Island, Alaska for Fukushima-derived radionuclides: 54 northern fur seal, and nine putchki (wild celery, Angelica lucida) plants. Individual northern fur seal samples were below minimum detectable activity concentrations of (137)Cs and (134)Cs, but when composited, northern fur seal tissues tested positive for trace quantities of both isotopes. Radiocesium was detected at an activity concentration of 37.2 mBq (134)Cs kg(-1) f.w. (95% CI: 35.9-38.5) and 141.2 mBq (137)Cs kg(-1) f.w. (95% CI: 135.5-146.8). The measured isotopic ratio, decay-corrected to the date of harvest, was 0.26 (95% CI: 0.25-0.28). The Fukushima nuclear accident released (134)Cs and (137)Cs in roughly equal quantities, but by the date of harvest in July 2014, this ratio was 0.2774, indicating that this population of seals has been exposed to small quantities of Fukushima-derived radiocesium. Activity concentrations of both (134)Cs and (137)Cs in putchki were below detection limits, even for composited samples. Northern fur seal is known to migrate between coastal Alaska and Japan and the trace (134)Cs in northern fur seal tissue suggests that the population under study had been minimally exposed Fukushima-derived radionuclides. Despite this inference, the radionuclide quantities detected are small and no impact is expected as a result of the measured radiation exposure, either in northern fur seal or human populations consuming this species.
authors.affiliation: Colorado State University, Department of Environmental & Radiological Health Sciences, 1618 Campus Delivery, Fort Collins, CO 80523, USA. Electronic address: elizarue@lanl.gov.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ruedig
authors.affiliation: Colorado State University, Department of Microbiology, Immunology and Pathology, Veterinary Diagnostic Laboratory, 300 West Drake Rd, Fort Collins, CO 80523, USA.
authors.forename: Colleen
authors.initials: C
authors.lastname: Duncan
authors.affiliation: National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA.
authors.forename: Bobette
authors.initials: B
authors.lastname: Dickerson
authors.affiliation: National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Regional Office, PO Box 21668, Juneau, AK 99802, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Williams
authors.affiliation: National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gelatt
authors.affiliation: Colorado State University, Department of Environmental & Radiological Health Sciences, 1618 Campus Delivery, Fort Collins, CO 80523, USA.
authors.forename: Justin
authors.initials: J
authors.lastname: Bell
authors.affiliation: Colorado State University, Department of Environmental & Radiological Health Sciences, 1618 Campus Delivery, Fort Collins, CO 80523, USA.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Johnson
mesh_terms: D000413:Alaska; D029969:Angelica / Q000378:metabolism*; D000818:Animals; D002588:Cesium Radioisotopes / Q000032:analysis* / Q000378:metabolism; D005507:Food Contamination, Radioactive / Q000032:analysis*; D062406:Fukushima Nuclear Accident; D046069:Fur Seals / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000737:chemistry; D011834:Radiation Monitoring; D012990:Soil Pollutants, Radioactive / Q000032:analysis / Q000378:metabolism; D014875:Water Pollutants, Radioactive / Q000032:analysis / Q000378:metabolism
chemical_list: D002588:Cesium Radioisotopes; D012990:Soil Pollutants, Radioactive; D014875:Water Pollutants, Radioactive
keywords: Bioaccumulation; Cs-134; Cs-137; Fukushima; Nuclear reactor; Seal