江苏省居民镉的膳食暴露评估

目的 评估江苏省居民镉的膳食暴露水平并进行安全性评价.方法 食物中镉含量资料来源于2001-2006年江苏省12大类共229种食物中镉含量的监测;江苏居民膳食消费量数据来源于2002年中国居民营养与健康状况调查中江苏省居民3 d 24 h膳食回顾资料,共有调查对象3938名,分为<7、7～、13～、18～岁4个年龄组,共获得778种食物消费资料.分别采用点评估和简单分布评估方法计算镉的膳食暴露量,对不同年龄组镉的膳食暴露量进行比较,评价其安全性.结果 点评估结果显示,江苏省居民每天镉的膳食平均暴露量为5.7～8.6 μg/kg,为暂定每日允许摄入量(PTDI,1.0μg/kg)的567.1%～857.1%.简单分布评估结果显示,江苏省居民每天镉的膳食平均暴露量为0.2～0.4μg/kg,为PTDI的20%～40%;每周镉的膳食平均暴露量为1.4～2.5μg/kg,为暂定每周允许摄人量(PTWI,7.0μg/kg)的20%～35.7%.<7、7～、13～、18～岁年龄组居民每天镉的膳食暴露量的平均值分别为0.4.0.3、0.2、0.2μg/kg,差异有统计学意义(F=69.0,P<0.05);各年龄组每周镉的膳食暴露量平均值分别为2.5、2.0、1.4、1.4μg/kg,差异有统计学意义(F=41.6,P<0.05).<7、7～岁年龄组居民每天镉的膳食暴露餐的第97.5百分位数(P97.5)分别为1.4、1.2μg/kg,高于PTDI.13～、18～岁年龄组居民每天镉的膳食暴露量第99.0百分位数(P99.0)分别为1.3、1.1μg/kg.不同年龄组膳食中谷类来源的镉暴露量为每天21.5～253.4μg/kg,构成比为42.2%～47.8%.蔬菜来源的镉暴露量为每天8.0～119.4μg/kg,构成比为14.6%～20.1%.结论 简单分布评估得到的江苏居民镉的膳食暴露平均水平位于安全限值以下,且远低于点估计得到的暴露值.各年龄组均有每天或每周镉的膳食暴露量的P97.5、P99.0暴露量超过PTDI或PTWI安全限值.镉膳食暴露主要来源为谷类和蔬菜类.

Resident dietary exposure of cadmium in Jiangsu province

Objective To investigate the resident dietary cadmium exposurein Jiangsu province and assess its safety. Methods Cadmium concentration of 229 food items under 12 food groups were obtained from the food surveillance program in Jiangsu province between 2001 and 2006. Food consumption data of 778 food items of 3938 residents who were classified into four age groups( <7,7 - ,13 - ,18 - ) were got from the Nutrition and Health Status Survey of the Jiangsu resident in 2002 by 24 h dietary recall on three consecutive days. Dietary cadmium exposures for the residents of different age groups were obtained by using both point estimation and simple distribution estimation through integrating the two datasets above. The safety of dietary cadmium exposure was assessed. Results Point estimation showed that the average dietary cadmium intakes of different age groups ranged from 5.7 to 8.6 μg/kg, accounting for 567. 1% - 857. 1% of the provisional tolerable daily intake (PTDI, 1.0 μg/kg). Result of simple distribution method showed mean daily cadmium exposure of different age groups ranged from 0. 2 to 0. 4 μg/kg, accounting for 20% - 40% of PTDI. Mean weekly cadmium exposure ranged from 1.4 to 2.5μg/kg, accounting for 20% - 35. 7% of the provisional tolerable weekly intake (PTWI,7.0 μg/kg). The mean daily dietary cadmium exposure for different groups were as follows: <7,0.4 μg/kg; 7 - ,0.3 μg/kg; 13 - ,0.2 μg/kg; 18 - ,0.2 μg/kg.Differences of daily dietary cadmium exposures among groups were significant (F=69.0, P < 0. 05). The mean weekly dietary cadmium exposure for different groups were: <7,2.5μg/kg; 7 - ,2.0 μg/kg; 13 - , 1.4 μg/kg; 18-, 1.4 μg/kg. Differences of weekly dietary cadmium exposures among groups were also significant (F=41.6,P <0. 05). The P97.5 of daily cadmium exposure for <7 and 7 - were 1.4 and 1.2 μg/kg,respectively,both of which were higher than PTDI. The P99. 0 of daily cadmium exposure for 13-and 18 - were 1.3 and I. 1 μg/kg, respectively. The daily dietary exposure from cereals for different agegroups were 21.5 -253.4 μg/kg,occupying 42. 2%-47. 8% of the total daily exposure. Vegetables were 8.0-119.4 μg/kg, occupying 14.6% - 20. 1%. Conclusion The average level of dietary cadmium exposures for residents in Jiangsu province calculated by simple distribution estimation were much lower than that calculated by point estin, ation and were considered to be at no risk. P97.5 or P99.0 of daily or weekly dietary cadmium exposure of different age groups exceeded PTWI and PTDI. The main food types of dietary cadmium exposure were cereals and vegetables.