Distribution of Nitrate Content in Groundwater and Evaluation of Potential Health Risks: A Case Study of Rural Areas in Northern China

Abstract

Nitrate pollution is considered to be one of the most common environmental problems in groundwater, especially in areas affected by human mining, such as the arid region of northern China. However, the human health risk assessment of nitrate pollution in this area has not yet been carried out. In this study, groundwater samples were taken in the Selian mining area in Inner Mongolia to conduct a full analysis of water quality. On this basis, the groundwater quality, the distribution range of nitrate pollution, and human health risks were evaluated. The results show that the groundwater in the Selian mining area is neutral to alkaline, with high salinity and hardness. The concentration of nitrate ions in groundwater generally exceeds the standard, and the maximum exceeds 5.48 times the value specified in the Chinese national standard, indicating that groundwater nitrate pollution needs to be controlled urgently. Groundwater is polluted by large amounts of nitrogen fertilizer used by humans in agricultural activities. At the same time, mining activities have accelerated the severity and spread of pollution. Groundwater is not recommended for direct human life and irrigation use in the study area unless purification measures are taken. Nitrate pollution is more harmful to children through groundwater, about 1.54 times that of adults. Excess nitrate is transported into the body through drinking groundwater, so proper drinking water control will reduce the health risks of nitrate, such as centralized water supply. This study will provide a scientific basis for the rational use of groundwater and nitrate pollution control in the area.

Nitrate Water Contamination from Industrial Activities and Complete Denitrification as a Remediation Option

“…A study conducted by [41] revealed the impact of NO 3 − contamination of over 50 mg/L from one mine that was detected in water supplied to a village situated close to a mine in the Limpopo province of South Africa. Groundwater sampled around the Selian mining area in China revealed a maximum NO 3 − concentration of 109 mg/L, which is alarmingly higher than the global acceptable 10 mg/L limit [22]. Most South African mines use ammonium-based explosives, although less data is available on water quality contaminated with NO 3 − from explosives used during mining.…”

“…− concentration [87,88]. During mining, tailings that are transported to the surface from the pits are piled next to the mine, where the residual explosives are washed off and dissolve in rain water, which eventually flows into nearby streams and rivers, resulting in elevated NO 3 − concentrations [9,19,22]. Mine wastewater remediation strategies tend to focus on metal and SO 4 2− remediation due to their known toxicity and lethality, while NO 3 − remediation garners less focus.…”

“…Such increasing and continuous losses of groundwater from NO 3 − contamination has led to the development and application of various physical, chemical, and biological NO 3 − remediation methods in attempt to mitigate contamination [19,20]. Most African countries, including South Africa, have been experiencing exponential increase of NO 3 − contamination in both surface and groundwater sources due to extensive agricultural [21] and mining practices [22], which has elicited major public concern and research into sustainable remediation strategies for NO 3 − contamination [12]. In oxygenated environments such as flowing rivers and the upper layers of the soil, biological nitrification is favored, converting most NH 4 + to yield more NO 3 − compared to other nitrogen species.…”

Research on Rural Environmental Pollution Control Path Under Administrative Intervention Mechanism

“…It not only helps to improve rural residents' participation in environmental pollution control but also helps to weaken social contradictions and promote the healthy development of rural environmental pollution control [9]. However, from the perspective of administrative management, rural environmental pollution control still faces some difficulties, such as unclear legal responsibility of administrative subjects, single relief methods for administrative damage, small scope of application of administrative management, and lack administrative procedures [10]. In this regard, to give full play to administrative management in rural environmental pollution control, all regions also need to clarify the legal responsibilities of administrative subjects and expand administrative damage relief methods and scientific design procedures.…”

Association between Type of Drinking Water and Upper Gastrointestinal Cancer Incidence in the Linxian General Population

“…Similar to perchlorate exposure, one of a major source of nitrate intake is from drinking water [8]. Generally, nitrate does not directly affect the human body, but when converted into nitrite in the digestive tract, it can induce certain diseases, such as cancer [9]. In addition, de ciency of trace elements and microbial contamination in drinking water could also affect the occurrence of EC and GC [10][11][12].…”