Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay-Aux-Roses 92260, France.
Rivne Nuclear Power Plant (ENERGOATOM), Varash, Rivne Region 34400, Ukraine.
Environ Sci Technol. 2021 Oct 19;55(20):13834-13848. doi: 10.1021/acs.est.1c03314. Epub 2021 Sep 29.
From early April 2020, wildfires raged in the highly contaminated areas around the Chernobyl nuclear power plant (CNPP), Ukraine. For about 4 weeks, the fires spread around and into the Chernobyl exclusion zone (CEZ) and came within a few kilometers of both the CNPP and radioactive waste storage facilities. Wildfires occurred on several occasions throughout the month of April. They were extinguished, but weather conditions and the spread of fires by airborne embers and smoldering fires led to new fires starting at different locations of the CEZ. The forest fires were only completely under control at the beginning of May, thanks to the tireless and incessant work of the firefighters and a period of sustained precipitation. In total, 0.7-1.2 TBq Cs were released into the atmosphere. Smoke plumes partly spread south and west and contributed to the detection of airborne Cs over the Ukrainian territory and as far away as Western Europe. The increase in airborne Cs ranged from several hundred μBq·m in northern Ukraine to trace levels of a few μBq·m or even within the usual background level in other European countries. Dispersion modeling determined the plume arrival time and was helpful in the assessment of the possible increase in airborne Cs concentrations in Europe. Detections of airborne Sr (emission estimate 345-612 GBq) and Pu (up to 75 GBq, mostly Pu) were reported from the CEZ. Americium-241 represented only 1.4% of the total source term corresponding to the studied anthropogenic radionuclides but would have contributed up to 80% of the inhalation dose.
从 2020 年 4 月初开始，乌克兰切尔诺贝利核电厂（CNPP）周边高度污染地区发生了野火。大约 4 周的时间里，火势在切尔诺贝利隔离区（CEZ）周围和内部蔓延，距离 CNPP 和放射性废物储存设施都只有几公里远。4 月份发生了多次野火。火势被扑灭了，但天气条件和火乘风蔓延，以及闷烧的火势，导致 CEZ 的不同地点又开始新的火灾。多亏了消防员不知疲倦的不懈努力和持续一段时间的降水，森林大火才在 5 月初完全得到控制。总共有 0.7-1.2 TBq 的 Cs 被释放到大气中。烟雾羽流部分向南和向西扩散，导致乌克兰领土以及远至西欧的上空检测到了空气中的 Cs。空气中的 Cs 浓度从乌克兰北部的几百 μBq·m 到trace 水平（几个 μBq·m 甚至在其他欧洲国家的正常背景水平内）不等。扩散模型确定了羽流到达的时间，有助于评估欧洲空气中 Cs 浓度可能增加的情况。从 CEZ 报告了空气中 Sr（排放量估计为 345-612 GBq）和 Pu（高达 75 GBq，主要是 Pu）的检测。241Am 仅占研究的人为放射性核素总源项的 1.4%，但可能占吸入剂量的 80%。
