日本福岛核事故期间浙江省环境放射性的监测结果及分析

Monitoring Results and Analysis of Environmental Radioactivity in Zhejiang Province during Japan's Fukushima Nuclear Power Station Accident

汇总了日本福岛核电站事故期间浙江省的环境γ辐射空气吸收剂量率、空气中放射性惰性气体氙浓度的测量结果以及气溶胶、雨水、生物等样品中的人工放射性核素的分析结果。结果如下:浙江省境内γ辐射空气吸收剂量率平均值为65.2 nGy/h,未见异常;3月25日开始,空气中放射性惰性气体中133Xe、131mXe浓度较本底有明显的上升,5月初呈逐渐回落的趋势,且与相同点位采集的气溶胶样品中131I、134Cs、137Cs的活度浓度变化趋势一致;在4月3日杭州采集的雨水样品中检测到了微量的131I,用放化法和γ谱法测得的结果分别为0.18 Bq/L和0.24 Bq/L;4月7日,在青菜和菠菜样品中检测出微量人工放射性核素131I和137Cs,而牛奶、鱼等生物样品中未检测出人工放射性核素。监测结果表明,在3月下旬至4月中旬,日本福岛核电站事故对浙江省辐射环境产生了较轻微的影响,部分辐射环境监测结果略高于本底环境水平。

In this paper, monitoring results of gamma-ray absorbed dose rates, xenon gas concentrations and levels of artificial radioactive nuclides in aerosol, rainwater and living organisms sampled in Zhejiang Province during the Fukushima accident are presented. The monitoring results show that the averaged γ radiation dose rate of Zhejiang Province was 65.2 nGy/h, which was mainly consistent with the backgro und level; comparing with background, concentrations of mXe and 133mXe ascended significantly since March 25, then descended gradually in early May that echoed with the concentration variations of 131I, 134Cs and 137Cs in aerosol samples at the same spot; Trace amount of 131I was detected in sampled rainwater from Hangzhou on April 3, the concentrations of which by radiochemical method and γ spectrometry were 0. 18 Bq/L and 0.24 Bq/L respectively; Trace amount of artificial radioactive nuclid es 131I and 137Cs were detected in green vegetables and spinach samples on April 7, but no artificial radioac tire nuclides were detected in milk, fish and other biological samples. The results indicate that the accident in Japan caused slight affection to the environment of Zhejiang Province during late March to mid April with part of the monitoring results slightly above the background.