Zhang Li E, Huang Daizheng, Yang Jie, Wei Xiao, Qin Jian, Ou Songfeng, Zhang Zhiyong, Zou Yunfeng
Department of Occupational and Environmental Health, School of Public Health, Guangxi Medical University, Nanning 530021, China.
Department of Biomedical Engineering, School of Preclinical Medicine, Guangxi Medical University, Nanning 530021, China.
Environ Pollut. 2017 Mar;222:118-125. doi: 10.1016/j.envpol.2016.12.074. Epub 2017 Jan 4.
Studies have yet to evaluate the effects of water improvement on fluoride concentrations in drinking water and the corresponding health risks to Chinese residents in endemic fluorosis areas (EFAs) at a national level. This paper summarized available data in the published literature (2008-2016) on water fluoride from the EFAs in China before and after water quality was improved. Based on these obtained data, health risk assessment of Chinese residents' exposure to fluoride in improved drinking water was performed by means of a probabilistic approach. The uncertainties in the risk estimates were quantified using Monte Carlo simulation and sensitivity analysis. Our results showed that in general, the average fluoride levels (0.10-2.24 mg/L) in the improved drinking water in the EFAs of China were lower than the pre-intervention levels (0.30-15.24 mg/L). The highest fluoride levels were detected in North and Southwest China. The mean non-carcinogenic risks associated with consumption of the improved drinking water for Chinese residents were mostly accepted (hazard quotient < 1), but the non-carcinogenic risk of children in most of the EFAs at the 95th percentile exceeded the safe level of 1, indicating the potential non-cancer-causing health effects on this fluoride-exposed population. Sensitivity analyses indicated that fluoride concentration in drinking water, ingestion rate of water, and the exposure time in the shower were the most relevant variables in the model, therefore, efforts should focus mainly on the definition of their probability distributions for a more accurate risk assessment.
关于水质改善对饮用水中氟化物浓度的影响以及对中国地方性氟中毒病区（EFAs）居民相应健康风险的研究，尚未在全国层面展开评估。本文总结了已发表文献（2008 - 2016年）中有关中国地方性氟中毒病区水质改善前后水中氟化物的现有数据。基于这些获取的数据，采用概率方法对中国居民饮用改善后饮用水中氟化物暴露进行了健康风险评估。利用蒙特卡洛模拟和敏感性分析对风险估计中的不确定性进行了量化。我们的结果表明，总体而言，中国地方性氟中毒病区改善后饮用水中的平均氟化物水平（0.10 - 2.24毫克/升）低于干预前水平（0.30 - 15.24毫克/升）。在中国北方和西南部检测到最高的氟化物水平。中国居民饮用改善后饮用水相关的平均非致癌风险大多可接受（危害商数<1），但大多数地方性氟中毒病区95百分位数儿童的非致癌风险超过了安全水平1，表明对该氟暴露人群存在潜在的非致癌健康影响。敏感性分析表明，饮用水中的氟化物浓度、水的摄入率以及淋浴时的暴露时间是模型中最相关的变量，因此，为了进行更准确的风险评估，应主要致力于确定它们的概率分布。
