摘要
地下水是张掖盆地的重要水资源,其硝酸盐污染尚未得到足够重视。对张掖盆地2004、2015年地下水硝酸盐浓度进行了系统分析,并采用美国环境保护署(USEPA)推荐的健康风险评价模型评估了地下水硝酸盐的健康风险。结果表明:自2004年以来张掖盆地地下水硝酸盐污染日趋严重。2015年硝酸盐浓度最高已达到283.32 mg·L-1,17.61%的采样点硝酸盐氮浓度超过GB5749-2006《生活饮用水卫生标准》中饮用地下水限量值(20 mg·L-1)。研究区人群经皮肤接触途径摄入硝酸盐的健康风险在可接受水平,而饮水摄入硝酸盐的健康风险较高,总风险中饮水途径引起健康风险的贡献率占99.40%,远大于皮肤接触途径。儿童经饮水摄入和皮肤接触两种途径的健康风险均显著高于成人,分别为成人的1.544倍和1.039倍。32.39%的采样点地下水硝酸盐对儿童的健康风险超出了可接受水平,14.79%的采样点地下水硝酸盐对成人的健康风险不可接受。甘州区城区、临泽县北部边缘及高台县城区周围硝酸盐浓度最高,这些区域内所有人群都面临硝酸盐引发的高健康风险,其余区域硝酸盐引发的健康风险相对较低。
Groundwater is an important water resource in Zhangye Basin that is a typical inland river basin.However,groundwater nitrate pollution in this region has not been paid enough attention.This study analyzed the concentrations of groundwater nitrate in Zhangye Basin and evaluated the health risks posed by groundwater nitrate using the health risk assessment model recommended by the US Environmental Protection Agency(USEPA).The results show that the groundwater nitrate pollution in Zhangye Basin has become increasingly serious since 2004.The highest nitrate concentration reached 283.32 mg·L-1 in 2015.Concentrations of NO-3-N at more than 17.61%of the sample sites exceeded the Grade III threshold(20 mg·L-1).The non-carcinogenic risks of nitrate through dermal contact pathway in the study area were at acceptable level while those through ingestion(by drinking water)was relatively higher.Non-carcinogenic risks caused by drinking water,much higher than those posed by dermal contact,contributed to 99.40%of the total risks,which indicated that groundwater nitrate affected human health mainly through ingestion pathway.The nitrate health risks for children through drinking water and dermal contact pathways were 1.544 and 1.039 times those of adults.The health risks at 32.39%of the sampling sites exceeded the acceptable level for children while those at 14.79%of the sampling sites were unacceptable for adults.The concentrations of groundwater nitrate in Ganzhou district,the northern edge of Linze County and the surrounding areas of Gaotai County were the highest so that residents in these regions were facing the highest health risks.The results of this study suggest that groundwater monitoring and effective nitrate control in Zhangye Basin are needed.
作者
盛丹睿
温小虎
冯起
武君
司建华
吴敏
Sheng Danrui;Wen Xiaohu;Feng Qi;Wu Jun;Si Jianhua;Wu Min(Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University ofChinese Academy of Sciences,Beijing 100049,China;Qinghai Institute of Salt Lakes,Chinese Academy of Sciences,Xining,810008,China)
出处
《中国沙漠》
CSCD
北大核心
2019年第5期37-44,共8页
Journal of Desert Research
基金
国家重点研发计划项目(2017YFC0404305)
中国科学院前沿科学重点研究项目(QYZDJ-SSW-DQC031)
青海省应用基础研究项目(2016-ZJ-755)
中国科学院“西部之光”人才计划项目
关键词
地下水
硝酸盐
健康风险评价
张掖盆地
groundwater
nitrate
health risk assessment
Zhangye Basin
