Rääf C L, Hubbard L, Falk R, Agren G, Vesanen R
Department of Radiation Physics, Lund University, Malmö University Hospital, SE-205 02 Malmö, Sweden.
Sci Total Environ. 2006 Aug 15;367(1):324-40. doi: 10.1016/j.scitotenv.2005.12.006. Epub 2006 Feb 28.
Data from measurements on the body burden of (134)Cs, (137)Cs and (40)K in various Swedish populations between 1959 and 2001 has been compiled into a national database. The compilation is a co-operation between the Departments of Radiation Physics in Malmö and Göteborg, the National Radiation Protection Authority (SSI) and the Swedish Defense Research Agency (FOI). In a previous study the effective ecological half time and the associated effective dose to various Swedish populations due to internal contamination of (134)Cs and (137)Cs have been assessed using the database. In this study values of human body burden have been combined with data on the local and regional ground deposition of fallout from nuclear weapons tests (only (137)Cs) and Chernobyl debris (both (134)Cs and (137)Cs), which have enabled estimates of the radioecological transfer in the studied populations. The assessment of the database shows that the transfer of radiocesium from Chernobyl fallout to humans varies considerably between various populations in Sweden. In terms of committed effective dose over a 70 y period from internal contamination per unit activity deposition, the general (predominantly urban) Swedish population obtains 20-30 microSv/kBq m(-2). Four categories of populations exhibit higher radioecological transfer than the general population; i.) reindeer herders ( approximately 700 microSv/kBq m(-2)), ii.) hunters in the counties dominated by forest vegetation ( approximately 100 microSv/kBq m(-2)), iii.) rural non-farming populations living in sub-arctic areas (40-150 microSv/kBq m(-2)), and iv.) farmers ( approximately 50 microSv/kBq m(-2)). Two important factors determine the aggregate transfer from ground deposition to man; i.) dietary habits (intakes of foodstuff originating from natural and semi-natural ecosystems), and ii.) inclination to follow the recommended food restriction by the authorities. The transfer to the general population is considerably lower ( approximately a factor of 3) for the Chernobyl fallout than during the 1960s and 70s, which is partly explained by a higher awareness of the pathways of radiocaesium to man both by the public and by the regulating authorities, and by the time-pattern of the nuclear weapons fallout during the growth season in Sweden.
1959年至2001年间，瑞典不同人群体内（134）铯、（137）铯和（40）钾负荷量的测量数据已被汇编成一个国家数据库。这项汇编工作是马尔默和哥德堡的辐射物理部门、国家辐射防护局（SSI）以及瑞典国防研究局（FOI）合作完成的。在之前的一项研究中，利用该数据库评估了瑞典不同人群因（134）铯和（137）铯内部污染导致的有效生态半衰期和相关有效剂量。在本研究中，人体负荷量值与核武器试验沉降物（仅（137）铯）和切尔诺贝利残骸（（134）铯和（137）铯）在当地和区域地面沉积的数据相结合，从而能够估算出所研究人群中的放射生态转移情况。对该数据库的评估表明，切尔诺贝利沉降物中放射性铯向人类的转移在瑞典不同人群之间差异很大。就单位活度沉积导致的内部污染在70年期间的待积有效剂量而言，瑞典普通（主要是城市）人群获得的剂量为20 - 30微希沃特/千贝克勒尔·平方米（-2）。有四类人群的放射生态转移高于普通人群：i.）驯鹿牧民（约700微希沃特/千贝克勒尔·平方米（-2）），ii.）森林植被占主导的县的猎人（约100微希沃特/千贝克勒尔·平方米（-2）），iii.）生活在亚北极地区的农村非农业人口（40 - 150微希沃特/千贝克勒尔·平方米（-2）），以及iv.）农民（约50微希沃特/千贝克勒尔·平方米（-2））。有两个重要因素决定了从地面沉积到人体的总转移量：i.）饮食习惯（来自自然和半自然生态系统的食物摄入量），以及ii.）遵循当局建议的食物限制的倾向。切尔诺贝利沉降物对普通人群的转移量比20世纪60年代和70年代低得多（约为三分之一），部分原因是公众和监管当局对放射性铯进入人体途径的认识提高，以及瑞典生长季节核武器沉降物的时间模式。
