School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794, USA.
Proc Natl Acad Sci U S A. 2013 Jun 25;110(26):10670-5. doi: 10.1073/pnas.1221834110. Epub 2013 Jun 3.
Radioactive isotopes originating from the damaged Fukushima nuclear reactor in Japan following the earthquake and tsunami in March 2011 were found in resident marine animals and in migratory Pacific bluefin tuna (PBFT). Publication of this information resulted in a worldwide response that caused public anxiety and concern, although PBFT captured off California in August 2011 contained activity concentrations below those from naturally occurring radionuclides. To link the radioactivity to possible health impairments, we calculated doses, attributable to the Fukushima-derived and the naturally occurring radionuclides, to both the marine biota and human fish consumers. We showed that doses in all cases were dominated by the naturally occurring alpha-emitter (210)Po and that Fukushima-derived doses were three to four orders of magnitude below (210)Po-derived doses. Doses to marine biota were about two orders of magnitude below the lowest benchmark protection level proposed for ecosystems (10 µGy⋅h(-1)). The additional dose from Fukushima radionuclides to humans consuming tainted PBFT in the United States was calculated to be 0.9 and 4.7 µSv for average consumers and subsistence fishermen, respectively. Such doses are comparable to, or less than, the dose all humans routinely obtain from naturally occurring radionuclides in many food items, medical treatments, air travel, or other background sources. Although uncertainties remain regarding the assessment of cancer risk at low doses of ionizing radiation to humans, the dose received from PBFT consumption by subsistence fishermen can be estimated to result in two additional fatal cancer cases per 10,000,000 similarly exposed people.
2011 年 3 月日本地震和海啸后，来自受损的福岛核反应堆的放射性同位素在当地海洋动物和洄游性太平洋蓝鳍金枪鱼（PBFT）中被发现。该信息的公布在全球范围内引起了反应，导致公众焦虑和担忧，尽管 2011 年 8 月在加利福尼亚捕获的 PBFT 的放射性活度浓度低于天然放射性核素。为了将放射性与可能的健康损害联系起来，我们计算了福岛衍生放射性核素和天然放射性核素对海洋生物群和人类食用鱼类的剂量。结果表明，在所有情况下，剂量均主要由天然放射性α发射体（210）Po 决定，福岛衍生剂量比（210）Po 衍生剂量低三个到四个数量级。海洋生物群的剂量比为生态系统提出的最低基准保护水平（10µGy⋅h(-1)) 低两个数量级。美国食用受污染 PBFT 的人类的额外福岛放射性核素剂量分别为普通消费者和自给渔民的 0.9 和 4.7µSv。这些剂量与人类从许多食物、医疗、航空旅行或其他背景来源中自然获得的天然放射性核素的常规剂量相当，或者低于常规剂量。尽管人类在低剂量电离辐射下的癌症风险评估仍存在不确定性，但自给渔民食用 PBFT 所接受的剂量可估计导致每 1000 万人中额外增加 2 例致命癌症病例。
