杭州产大米中重金属污染状况调查及暴露风险评估

Survey of heavy metal contamination and risk assessment of exposure in Hangzhou indigenous rice

目的了解杭州地区本地产大米中砷、汞、铅、镉、铬、镍污染状况,对杭州农村居民大米重金属暴露进行风险评估。方法随机采集杭州地区主要产粮区的大米样品,用微波消解-电感耦合等离子体质谱法检测;用人均月(周)摄入大米量和平均体质量估算米中重金属摄入量占暂定每月(周)允许摄入量的比重。结果113份大米中镉含量为0.010 mg/kg^2.46 mg/kg,超标率为42.6%;铅含量为0.00014 mg/kg^0.262 mg/kg,超标率为0.88%;总汞含量为0.0014 mg/kg^0.0196 mg/kg;铬含量为0.0058 mg/kg^0.377 mg/kg;总砷含量为0.051 mg/kg^0.204 mg/kg;镍含量为0.041 mg/kg^1.003 mg/kg;总汞、铬均未有超标。估算农村居民每月通过大米摄入镉为22.30μg/kg·BW;每周分别摄入铅的平均量为0.46μg/kg·BW;摄入汞的平均量为0.21μg/kg·BW;摄入铬的平均量为1.87μg/kg·BW;摄入砷的平均量为2.44μg/kg·BW;摄入镍的平均量为5.68μg/kg·BW。结论本地产大米中砷、汞、铅、镉、铬、镍均有检出,其中镉含量偏高,暴露风险较高,应加强监测,采取措施,控制污染。

Objective The contamination of arsenic,mercury,lead,cadmium,chromium and nickel in Hangzhou indigenous rice were investigated.And the health risk assessment of heavy metal for Hangzhou rural residents was evaluated.Methods The rice samples were randomly collected from the local breadbaskets in Hangzhou area for the detection of heavy metals by microwave digestion-inductively coupled plasma mass spectrometry(ICP-MS).Meanwhile,the proportion of monthly(weekly)intake of heavy metals to provisional tolerable monthly(weekly)intake was also estimated.Results Among 113 samples of rice,the levels of cadmium and lead are within 0.010 mg/kg-2.46 mg/kg and 0.00014 mg/kg-0.262 mg/kg,and the exceeding standard rate is 42.6%and 0.88%,respectively.The contents of mercury and chromium in rice are within 0.0014 mg/kg-0.0196 mg/kg and 0.0058 mg/kg-0.377 mg/kg,respectively.The levels of arsenic and nickel in rice are within 0.051 mg/kg-0.204 mg/kg and 0.041 mg/kg-1.003 mg/kg,exceeding the standards.For the rural residents,the amount of intake exposure of cadmium from rice is 22.30μg/kg·BW per month;the amount of intake exposure from rice is 0.46μg/kg·BW,0.21μg/kg·BW,1.87μg/kg·BW,2.44μg/kg·BW and 5.68μg/kg·BW per week for lead,mercury,chromium,arsenic and nickel,respectively.Conclusion Arsenic,mercury,lead,cadmium,chromium and nickel were all detected in Hangzhou indigenous rice.The contamination of cadmium in rice is at high level and the exposure risks for rural residents are relatively high.The surveillance and control should be strengthened in this area.