靖边县地下水氟影响因素及健康风险评价

周佩瑶 杨乔洋 王玮

摘 要：基于靖边县61组地下水样检测结果，运用相关性分析和水文地球化学方法，分析了F-分布特征及富集的影响因素，并结合US EPA非致癌健康风险评价模型进行了健康风险评价，结果表明：第四系含水层中F-超标区域分布于柠条梁、王渠则至县城一带，白垩系含水层F-超标区域为柠条梁和席麻湾至县城一带，超标面积较第四系含水层小;含氟矿物是F-的主要来源，蒸发作用、离子交换作用和矿物质的饱和状态是地下水中F-富集的主要原因，而人类活动的影响甚微;部分区域健康风险高，建议以第四系含水层中地下水为水源的地区建立除氟处理设施、集中供水或雨水收集系统，以确保饮用水安全。

关键词：氟;第四系含水层;白垩系含水层;健康风险评价;靖边县

中图分类号：P641   文献标志码：A

doi：10.3969/j.issn.1000-1379.2020.07.014

Abstract：Based on the data of 61 groundwater samples from Jingbian， the correlation analysis and hydrogeochemical methods were applied to study the fluorine distribution characteristics and influencing factors. At the same time， the health risk assessment of F- was assessed with the health risk assessment model recommended by US EPA. The results show that the high-fluorine water of the quaternary aquifer mainly distributes from Ningtiaoliang， Wangquze to the county， which of the cretaceous aquifer mainly distributes from Ningtiaoliang， Ximawan to the county. The fluorine content in the quaternary aquifer is higher than that in the cretaceous aquifer. Fluorine in groundwater primarily comes from the fluorine minerals. The main enrichment mechanisms of fluorine in groundwater are the evaporation condensation， ion exchange and mineral saturation and human factors have a small impact. The health risk of the quaternary aquifer is higher than that of the cretaceous aquifer. Establishing central water supply system and rainwater collecting system are suggested to guarantee safe drinking water in this area.

Key words： fluoride; quaternary aquifer; cretaceous aquifer; health risk assessment; Jingbian County

1 研究背景

氟与人体健康密切相关，低氟水（0.5～1.0 mg/L）的攝入有助于预防龋齿和加强骨骼，而高氟水（>1.0 mg/L）的摄入不仅会导致硬组织畸形，即氟斑牙和氟骨症，还会造成肝、肾、肺等损伤[1-2]，因此高氟水的研究备受关注。Wei等[3]立足我国西北地区，分析了第四系沉积含水层和第三系碎屑含水层中氟化物的富集情况;李培月等[4]以铜川市为研究对象，综合分析了地下水中氟化物的空间分布和成因，提出通过建立集中供水系统来保障该地区的饮水安全;吴建华等[5]、朱亮等[6]分别以石嘴山、兰州市为例，探究了自然因素和人为因素影响下高氟水的动态变化特征。高氟水研究的常用方法有相关性分析法[7]、水文地球化学法[8]和数值模拟法[9]等。