广东省沿海城市居民膳食结构及食物污染状况的调研--对持久性卤代烃和重金属的人体暴露水平评价

Nutritional Status in Dietary Intake and Pollutants via Food in Coastal Cities of Guangdong Province,China——Assessment of Human Exposure to Persistent Halogenated Hydrocarbons and Heavy Metals

自改革开放以来,广东沿海城市逐步成为经济发展的热点地区。飞速的经济发展、快速的城市化进程以及有机氯农药的历史使用等原因,使得广东省内环境介质受到持久性卤代烃和重金属污染,这些污染物最终主要通过食物影响到处于生物链终端的人类。本文运用随机抽样的方法对广东省经济较发达的12个沿海城市居民的膳食情况进行问卷调查,分析其膳食营养状况。同时,结合该地区食物中持久性卤代烃和重金属的污染水平,对居民通过食物摄入的污染物进行人体暴露水平评价。结果表明,广东省沿海城市居民对蛋类、豆制品、乳品及水果的消费量均高于广东省平均水平,而蔬菜、禽肉和谷物的摄入量却低于广东省平均水平。与国家推荐摄入量相比,居民对蔬菜的摄入量仅为推荐量的一半,乳品的摄入也明显偏低。若以每标准人为单位,广东省沿海居民日均摄入能量低于全国平均值,占参考摄入量的90%,视黄醇、硫胺素、核黄素的日均摄入量也低于我国推荐值,而蛋白质和脂肪的日均摄入量则明显超出推荐值。而且,广东省沿海城市居民每日通过食物对持久性卤代烃的摄入量没有超过世界粮农组织和世界卫生组织(FAO/WHO)规定的每日允许摄入量。讨论了膳食中铅、砷、镉、铬4种金属的人体暴露情况,金属铅、砷和铬的暴露水平处于安全线内,但是金属镉的日均摄入量与FAO/WHO规定的最大耐受量相同。

Coastal cities in Guangdong Province are relatively well developed as a result of the economic reform initiated nearly 30 years ago. The rapid economic development and urbanization combined with certain historical reasons have led to substantial accumulation of anthro- pogenic pollutants, such as persistent halogenated hydrocarbons and heavy metals, in the environment. These contaminations may pose health risk to humans via food consumption. Using a question-answer approach, we randomly surveyed a total of 1 786 residents in 12 costal cities of Guangdong Province to obtain dietary data, which allowed a comprehensive assessment of the current nutrient consumption. In addition, hu- man exposure to persistent halogenated hydrocarbons and heavy metals via food consumption was assessed based on published contaminant concentration data. The results indicated that the average daily intakes of egg, bean, milk, and fruit for coastal residents were higher than those for the entire Guangdong Province, but the opposite was true for the daily intakes of vegetable, meat, and corn. The consumption rate of vegetable for the surveyed residents was only 50% of the government-recommended value, and that of milk was also lower than the national level. Moreover, the average daily intake of total calories was approximately 90% of the government-recommended value using an 18-year old male as the reference. The ingestion amounts of retinol, thiamine, and riboflavin were also lower than the recommended values, whereas those of protein and adipose were much higher than the recommended values. Furthermore, the daily intakes of persistent halogenated hydrocarbons via food were lower than the Acceptable Daily Intakes recommended by the FAO/WHO. The daily intakes of lead, chromium, arsenic via food consumption were lower than the Acceptable Daily Intakes recommended by the FAO/WHO, but that of cadmium was equal to the FAO/WHO recommended value.