Iodine-129 in snow and seawater in the Antarctic: level and source.
Iodine-129 in snow and seawater in the Antarctic: level and source.
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DOI：
10.1021/acs.est.5b01234
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发表时间：
2015-05
影响因子：
11.4
通讯作者：
S. Xing;X. Hou;A. Aldahan;G. Possnert;K. Shi;P. Yi;Weijian Zhou
中科院分区：
文献类型：
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作者：
S. Xing;X. Hou;A. Aldahan;G. Possnert;K. Shi;P. Yi;Weijian Zhou
自20世纪40年代以来，人类核活动以不同的方式和化学形态向环境中释放了人源129 I。这些来源为追踪挥发性污染物在大气中的扩散提供了理想的工具。对2011年在南极洲别林斯高晋海、阿蒙森海和罗斯海采集的雪和海水样品进行了（129）I和（127）I分析，包括有机形态;观测到南极表层海水中的（129）I/（127）I原子比（（6.1-13）× 10（-12））比南极雪低2个数量级（6.8-9.5）× 10 ~（-10）），但比核前水平（1.5 × 10 ~（-12））高4-6倍，表明南极环境中的~（129）I主要是人为来源。南极雪中~（129）I水平比北方半球低2-4个数量级，但与南半球其它站点观测值相比并不显著增高。这一特征表明，南极雪中的（129）I主要来源于1945 ~ 1980年的大气核武器试验，沉降物（129）I在南半球的再悬浮和再发射维持了南极大气中的（129）I水平。欧洲后处理厂直接排放到大气中的（129）I和海洋排放的（129）I可能不会大量扩散到南极洲。
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.