几种海洋软体动物对低放射性水平^(65)Zn和^(134)Cs的积累、分布和排泄

ACCUMULATION, DISTRIBUTION AND EXCRETION OF LOW LEVEL OF ^(65)Zn AND ^(134)Cs IN SOME MARINE MOLLUSC

在大亚湾核电站附近的潮间带采集腹足类的滨螺(Littorinopsis sp.)、桑椹螺(Clypemorus humilis)、沟纹笋光螺(Terebralia sulcata)和瓣鳃类的畸心蛤(Anomalocardio flexuosa),于室内进行^(65)Zn和^(134)Cs的吸收积累、分布和排泄试验。结果表明,这些海洋软体动物对低放射性水溶液的^(65)Zn有较大的吸收能力,且腹足类大于瓣鳃类。积累试验第9天,滨螺、桑椹螺、沟纹笋光螺对^(65)Zn的吸收率分别为32.33％、37.30％和15.14％,畸心蛤为11.95％;腹足类的3种螺对^(134)Cs的吸收率分别为1.30％,1.08％和1.53％,畸心蛤为1.39％。^(65)Zn在畸心蛤各器官组织的分布顺序为:外套腔液>鳃>内脏团>外套膜>闭壳肌>贝壳>足。排泄试验结果表明,上述动物体内的放射性核素积累按方程式y=A.e^(-λτ)的规律下降。

The accumulation,distribution and excretion of 65Zn and 134Cs by the marine organism were investigated using four kinds of marine mollusc: Littorinopsis sp.Clypemorus humilis,Terebralia sulcata and Anomalocardio flexuosa,which were collected in Dong Shan of tidal zone near Dayawan nuclear power station.The results showed that different kinds of marine mollusc had considerable capability of concentrating 65Zn in low radioactive level water and Gastropoda had greater capability than Bivalce.The absorption rate of Littorinopsis sp.,Clypemorus humilis and Terebralia sulcata were 32.3%,37.3% 15.14% respectively and Anomalocardio flexuosa was 11.95% on the 9th day of accumulation experiment.The absorption rate of above three kinds conches for 134Cs were 1.3%,1.08%,1.53% respectively and that of Anomalocardio flexuosa was 1.39%.It indicated that there was no significant differences between the absorption rate of Gastropoda and Bivalve for 134Cs,which was much lower than that of 65Zn.The distribution order (from high to low) of 65Zn in different organs and tissues of Anomalocardio flexuosa was mantle cavity Iiquid>gill>viscera mass>mantle>adductor muscle>shell> foot.The results of excretion experiment indicated that radioactivities accumulated in all kinds of the animal bodies decreased in accordance with the equation of y=A.eλt