2002—2018年陕西省市售谷物中铅、镉、总汞和总砷污染状况及暴露评估

Pollution status and exposure assessment of lead,cadmium,total mercury and total arsenic in grains on sale from Shaanxi Province,2002-2018

目的探讨陕西省市售谷物中铅、镉、总汞和总砷污染状况,并分析潜在的膳食暴露风险。方法 2002—2018年在流通环节随机采集小麦、小麦粉、稻米、玉米及其制品1873份,采用原子吸收分光光度法和电感耦合等离子体质谱法测定铅和镉含量,原子荧光光谱法测定总汞和总砷;采用单因子污染指数法评价谷物中4种元素污染状况、暴露边界比(margin of exposure, MOE)进行铅暴露评估、每月摄入量与每月可耐受摄入量的比值进行镉暴露评估、每周摄入量与每周可耐受摄入量的比值进行汞和砷的暴露评估。结果陕西省市售谷物食品中铅、镉、总汞和总砷的平均值为0.070、0.022、0.0079和0.030 mg/kg,铅、镉和总汞的总超标率为6.30%、1.39%和4.43%;铅、镉、总汞与总砷的均数单因子污染指数均<0.7;谷物中铅MOE为0.99~18.41,谷物镉摄入量占每月可耐受摄入量的19.08%,汞、砷摄入量占每周可耐受摄入量的10.28%、10.67%。结论 2002—2018年监测的陕西省市售各类谷物中铅、镉、总汞、总砷污染较轻,摄入量均在安全范围内。

OBJECTIVE To investigate the pollution status of lead, cadmium, total mercury and total arsenic in grains sold in Shaanxi Province, and to analyze the potential risk of dietary exposure. METHODS A total of 1873 samples of wheat, wheat flour, rice, maize and their products were randomly collected in circulation. The contents of lead and cadmium were determined by atomic absorption spectrophotometry and inductively coupled plasma mass spectrometry, and total mercury and arsenic were determined by atomic fluorescence spectrometry. The pollution status of four elements in grains was evaluated by single factor pollution index method, margin of exposure(MOE) was used to assess lead exposure, cadmium exposure was assessed by the ratio of estimated monthly intake(EMI) to provisional tolerable monthly intake(PTMI), and exposure to mercury and arsenic was assessed using the ratio of estimated weekly intake(EWI) to provisional tolerable weekly intake(PTWI).RESULTS The average values of lead, cadmium, total mercury and total arsenic in grains sold in Shaanxi Province were 0.070, 0.022, 0.0079 and 0.030 mg/kg. The over-standard rates of lead, cadmium and total mercury were 6.30%, 1.39% and 4.43%. The average single factor pollution index of lead, cadmium, total mercury and total arsenic was less than 0.7;The MOE value of lead in grains was 0.99-18.41, the intake of cadmium in grains accounted for 19.08% of PTMI, and the intake of mercury and arsenic accounted for 10.28% and 10.67% of PTWI. CONCLUSION Lead, cadmium, total mercury and total arsenic in all kinds of cereals sold in Shaanxi Province from 2002 to 2018 were less polluted and their intake was within the safe range.