The contents of isotopes of plutonium (238Pu and 239, 240Pu) and 137Cs in samples of bottom sediments and hydrobionts (water moss, amphipods, and caddisfly larvae with casings) taken in the Yenisei River in the vicinity of the radioactive discharge from the Mining and Chemical Combine in 2012 and 2018 were comparatively estimated. It is shown that the content and ratios between the specific activities of plutonium isotopes (238/239 and 240) in samples of BSs and hydrobionts increased after the recommencing of plutonium discharges into the Yenisei due to the beginning of MOX fuel production. The background content and the ratio between plutonium isotopes in BSs of the Yenisei were estimated for the first time. Hydrobionts and BSs were ranged differently according to the content of plutonium and 137Cs: we recorded the highest content of 137Cs in BSs and that of plutonium in water moss. The plutonium content in hydrobionts of the Yenisei River varies considerably, which permits specification of representatives of biota (water moss and caddisfly larvae with casings) that, along with BSs, can be used as effective indicators of ecosystem pollution with plutonium.

中文翻译：

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叶尼塞河底部沉积物和水生生物中钚（238Pu、239+240Pu）和放射性铯（137Cs）含量的比较估算

在叶尼塞河采矿和放射性排放附近采集的底部沉积物和水生生物（水苔、片脚类动物和带壳的石蚕幼虫）样品中钚（238Pu 和 239、240Pu）和 137Cs 的同位素含量2012 年和 2018 年的化工联合体进行了比较估计。结果表明，由于开始生产 MOX 燃料，在重新开始向叶尼塞排放钚后，BSs 和水生生物样品中钚同位素比活（238/239 和 240）的含量和比值增加。首次估算了叶尼塞 BS 中钚同位素的本底含量和比值。Hydrobionts 和 BSs 的范围根据钚和 137Cs 的含量不同：我们记录了 BSs 中 137Cs 和水苔中钚的最高含量。叶尼塞河水生生物中的钚含量变化很大，这允许指定生物群的代表（水苔和带肠衣的石蛾幼虫），它们与 BS 一起可用作钚污染生态系统的有效指标。