State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, 418 Guanglan Road, Jingkai District, Nanchang, 330013, People's Republic of China.
Jiangxi Provincial Key Laboratory of Genesis and Remediation of Groundwater Pollution and School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang, 330013, People's Republic of China.
Environ Geochem Health. 2024 Aug 20;46(9):366. doi: 10.1007/s10653-024-02166-1.
Groundwater nitrate (NO) contamination is a global concern. The distribution patterns, enrichment mechanisms, and human health risks of NO contaminated groundwater were investigated using 144 groundwater samples collected from domestic and irrigation wells in the piedmonts of the North China Plain (Beijing and Shijiazhuang areas). The results showed that the groundwater was neutral to weakly alkaline, and 47% of the groundwater samples had NO concentrations exceeding 50 mg/L, a threshold proposed by world health organization to threaten infants up to 3 months. Groundwater NO concentrations were generally higher in the Beijing piedmont than in the Shijiazhuang piedmont and decreased with depth in both piedmonts. High-NO (> 50 mg/L) groundwater was distributed sporadically spatially and mainly was of Ca-Mg-HCO hydrochemical facies. Stable isotopes (D and O) compositions and NO/Cl ratios indicated that NO accumulation in groundwater was primarily due to use of N-fertilizers under agricultural practices, and was associated with groundwater recharge sources such as septic tank leakage and re-infiltration of reclaimed irrigation water. Water quality evaluation showed that groundwater quality was highly dependent on NO concentration, with entropy-weighted water quality index values increasing linearly with increasing NO concentrations. The potential health risk of high-NO groundwater was the most serious for infants in both the piedmonts. Therefore, reducing NO input from sources and drinking water intake is recommended to minimize the human health risk.
地下水硝酸盐（NO）污染是一个全球性问题。本研究采用 144 个取自华北平原山前平原区（北京和石家庄地区）民井和农灌井的地下水样本，调查了地下水 NO 污染的分布模式、富集机制和对人体健康的风险。结果表明，地下水呈中性至弱碱性，47%的地下水样本中 NO 浓度超过 50mg/L，这一阈值被世界卫生组织（WHO）提出，以威胁 3 个月以下婴儿。北京山前平原的地下水 NO 浓度普遍高于石家庄山前平原，且在两个山前平原均随深度增加而降低。高浓度（>50mg/L）地下水呈点状空间分布，主要为 Ca-Mg-HCO 水化学类型。稳定同位素（D 和 O）组成和 NO/Cl 比值表明，农业施肥是导致地下水 NO 积累的主要原因，与地下水补给来源如化粪池渗漏和再生灌溉水的再入渗有关。水质评价表明，地下水质量高度依赖于 NO 浓度，熵权水质指数值随 NO 浓度的增加呈线性增加。高浓度 NO 地下水对两个山前平原区的婴儿健康风险最大。因此，建议减少来自源头和饮用水摄入的 NO 输入，以最大程度降低人体健康风险。
