基于参数实测的水中重金属暴露的健康风险研究

以位于长江和淮河流域交界处河南泌阳县为研究区,利用ICP/MS分析城镇和农村居民饮用水中14种重金属含量,抽样选取2 500名城镇和农村不同性别和年龄的受试者作为研究对象,详细记录受试者3 d内的饮水和皮肤接触水的活动频率,并对有关饮水和皮肤暴露参数进行了测量.用暴露和健康风险模型计算了城镇和农村居民对14种重金属的经...

Health Risk Assessment of Heavy Metals in Drinking Water Based on Field Measurement of Exposure Factors of Chinese People

This study was carried out in Biyang County,located in the junction of Yangtze river and Huaihe river. Drinking water samples of 20 sites in urban and rural areas in this county were collected to measure 14 heavy metals by ICP/MS. About 2500 subjects with different age and sex were selected to measure exposure factors. Time-activity of drinking water by ingestion and dermal contact of each individual subject during the last three days were kept in dairy in detail by questionnaires. Intake of drinking water from direct and indirect consumption of water and time duration of dermal contact to water in each individual subject were kept in record based on real time measurements. Human health risks were assessed and sensitivity of exposure factors and uncertainty of risks were also analyzed. The results showed that the average drinking water intake rate of male and female are 2276 mL/d,2265 mL/d in urban adults and 2464 mL/d,2170 mL/d in rural adults respectively. Body surface area of male and female are 1.806 m²,1.641 m² in urban adults and 1.747 m²,1.617 m² in rural adults respectively. The contents of 14 heavy metals in this study area are all below the national drinking water standards. Cancer risks from exposure to As are ranged from 2.5×10^-6 to 5.2×10^-6 through ingestion and 1.1×10^-7 to 2.3×10^-7 through dermal exposure.Non-cancer risks are ranged from 2.1×10^-7 to 1.7×10^-6 through ingestion and 1.0×10^-8 to 6.0×10^-8 through dermal exposure. Non-cancer risks in rural population are 2.1 times to 5.6 times to the risks in urban populations. However all the risks are below the acceptable level. The sensitivity of various exposure factors including drinking water intake rate,dermal exposure time and body surface area are 71.5% . This indicates that exposure factors play a very important role in health risk assessment. Health risks in this research based on real measurement of exposure factors are about 0.94 time to 6.33 times higher than the risks based on the references of the data from the exposure factors handbooks in other countries. This study showed that the accuracy of health risk assessment could be improved a lot by the real measurements of exposure factors. Attentions should be attached to exposure factor investigation to decrease uncertainty of health risk assessment.