Harrison J D, Smith H, David A J
National Radiological Protection Board, Didcot, Oxon, United Kingdom.
Sci Total Environ. 1988 Jan;68:187-96. doi: 10.1016/0048-9697(88)90371-3.
Winkles (Littorina littorea) and mussels (Mytilus edulis) collected on the Cumbrian coast contain americium-241 and isotopes of plutonium discharged from the nuclear-fuel reprocessing plant at Sellafield. Shellfish have been fed to rats and measurements made of the gastrointestinal absorption of the actinides. For shellfish collected over a 1-year period from March 1983 to February 1984, the average values for the fractional absorption of plutonium and americium were 9 x 10(-4) and 3 x 10(-4), respectively, for winkles and 1.5 x 10(-3) and 6 x 10(-4), respectively, for mussels. Comparisons with results for winkles collected in December 1981 and mussels collected in July 1982 suggest that there may be considerable seasonal variation in the availability of the actinides for absorption. The results suggest that in calculations of doses to individuals consuming shellfish in west Cumbria, it may be prudent to examine the effect of using the new ICRP gut transfer factor of 1 x 10(-3) for both actinides, in comparison with the value of 5 x 10(-4) recommended previously by NRPB. The use of 1 x 10(-3) would increase the estimate of the committed effective dose equivalent for 1985 intakes, from the value of 0.73 mSv calculated by the Ministry of Agriculture, Fisheries and Food, to 1.29 mSv. However, taking into account up-to-date estimates of the retention of the actinides in liver and bone would reduce this value to 1.07 mSv. If, in addition, allowance is made for the effect of the burial and recycling of actinides in bone, a significant reduction in the dose estimate could result; for example, the use of one proposed dynamic bone model would reduce the value from 1.07 to 0.54 mSv.
在坎布里亚海岸采集的滨螺（滨螺属）和贻贝（紫贻贝）含有从塞拉菲尔德核燃料后处理厂排放的镅 - 241和钚的同位素。已将贝类喂给大鼠，并对锕系元素在胃肠道的吸收情况进行了测量。对于1983年3月至1984年2月这1年期间采集的贝类，滨螺对钚和镅的分数吸收平均值分别为9×10⁻⁴和3×10⁻⁴，贻贝分别为1.5×10⁻³和6×10⁻⁴。与1981年12月采集的滨螺和1982年7月采集的贻贝的结果比较表明，锕系元素可供吸收的量可能存在相当大的季节性变化。结果表明，在计算坎布里亚西部食用贝类个体的剂量时，与国家辐射防护委员会先前推荐的5×10⁻⁴的值相比，谨慎的做法可能是研究对两种锕系元素都使用国际辐射防护委员会新的肠道转移因子1×10⁻³的影响。使用1×10⁻³会使1985年摄入量的待积有效剂量当量估计值从农业、渔业和食品部计算的0.73毫希沃特增加到1.29毫希沃特。然而，考虑到锕系元素在肝脏和骨骼中滞留的最新估计值，该值将降至1.07毫希沃特。此外，如果考虑到锕系元素在骨骼中的埋藏和再循环的影响，剂量估计值可能会显著降低；例如，使用一种提议的动态骨骼模型会使该值从1.07降至0.54毫希沃特。
