进口钛铁矿放射性超标事件的调查分析

Investigation Report on the Event of Radioactive Standard of Imported Ilmenite

2015年4月,湛江出入境检验检疫局对从湛江口岸进口的一批钛铁矿进行放射性监测,发现钛铁矿集装箱外的γ辐射剂量率水平值最高为920 n Gy/h,超出《有色金属矿产品的天然放射性限值》(GB20664-2006)的筛选水平。抽取样品进行核素分析,结果表明其中的232Th活度浓度为1.94 Bq/g,超过GB20664-2006的限量要求,判定为不合格。放射性超标物质输入中国,可能造成环境污染,对此出入境检验检疫机构应高度重视,加强对进口矿产品的放射性监测。

In April 2015,the Zhanjiang entry exit inspection and Quarantine Bureau monitors a batch of titanium iron ore for radioactive imported from Zhanjiang Port. It is found that the gamma radiation dose rate of the container is 920 n Gy/h,which is beyond the screening level of the natural radioactivity limit of the non-ferrous metal products（GB20664-2006）. The analysis of the samples was carried out,the results showed that the232 Th activity concentration was 1.94 Bq/g,and the limit of the natural radioactivity limit of the non-ferrous metal mineral products was more than limited requirement of GB20664-2006,which was judged to be unqualified. Radioactive materials is transferred to China,may cause environmental pollution,the entry and exit inspection and quarantine institutions should attach great importance to strengthen the radioactive monitoring of imported mineral products.