title: Iodine-129 in snow and seawater in the Antarctic: level and source.
abstract: Anthropogenic (129)I has been released to the environment in different ways and chemical species by human nuclear activities since the 1940s. These sources provide ideal tools to trace the dispersion of volatile pollutants in the atmosphere. Snow and seawater samples collected in Bellingshausen, Amundsen, and Ross Seas in Antarctica in 2011 were analyzed for (129)I and (127)I, including organic forms; it was observed that (129)I/(127)I atomic ratios in the Antarctic surface seawater ((6.1-13) × 10(-12)) are about 2 orders of magnitude lower than those in the Antarctic snow ((6.8-9.5) × 10(-10)), but 4-6 times higher than the prenuclear level (1.5 × 10(-12)), indicating a predominantly anthropogenic source of (129)I in the Antarctic environment. The (129)I level in snow in Antarctica is 2-4 orders of magnitude lower than that in the Northern Hemisphere, but is not significantly higher than that observed in other sites in the Southern Hemisphere. This feature indicates that (129)I in Antarctic snow mainly originates from atmospheric nuclear weapons testing from 1945 to 1980; resuspension and re-emission of the fallout (129)I in the Southern Hemisphere maintains the (129)I level in the Antarctic atmosphere. (129)I directly released to the atmosphere and re-emitted marine discharged (129)I from reprocessing plants in Europe might not significantly disperse to Antarctica.
authors.affiliation: †Xi'an AMS Center, SKLLQG, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Institute of Earth Environment, CAS, Xi'an 710061, China.|⊥University of Chinese Academy of Science, Beijing 100049, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Xing
authors.affiliation: †Xi'an AMS Center, SKLLQG, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Institute of Earth Environment, CAS, Xi'an 710061, China.|‡Technical University of Denmark, Center for Nuclear Technologies, Risø Campus, Roskilde 4000, Denmark.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Hou
authors.affiliation: §Department of Geology, United Arab Emirates University, Al Ain, United Arab Emirates.|#Department of Earth Sciences, Uppsala University, Uppsala 75120, Sweden.
authors.forename: Ala
authors.initials: A
authors.lastname: Aldahan
authors.affiliation: ∥Tandem Laboratory, Uppsala University, Uppsala 75120, Sweden.
authors.forename: Göran
authors.initials: G
authors.lastname: Possnert
authors.affiliation: ‡Technical University of Denmark, Center for Nuclear Technologies, Risø Campus, Roskilde 4000, Denmark.|¶School of Nuclear Science and Technology, Lanzhou University, 73000, Lanzhou, China.
authors.forename: Keliang
authors.initials: K
authors.lastname: Shi
authors.affiliation: §Department of Geology, United Arab Emirates University, Al Ain, United Arab Emirates.
authors.forename: Peng
authors.initials: P
authors.lastname: Yi
authors.affiliation: †Xi'an AMS Center, SKLLQG, Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application, Institute of Earth Environment, CAS, Xi'an 710061, China.
authors.forename: Weijian
authors.initials: W
authors.lastname: Zhou
mesh_terms: D000864:Antarctic Regions; D005591:Chemical Fractionation; D002681:China; D005060:Europe; D005618:Fresh Water / Q000737:chemistry; D005843:Geography; D006801:Humans; D007455:Iodine / Q000032:analysis*; D007457:Iodine Radioisotopes / Q000032:analysis; D010084:Oxidation-Reduction; D011891:Rain; D012015:Reference Standards; D012623:Seawater / Q000737:chemistry*; D012914:Snow / Q000737:chemistry*; D012972:Sodium Hydroxide / Q000737:chemistry
chemical_list: D007457:Iodine Radioisotopes; D012972:Sodium Hydroxide; D007455:Iodine