Affected by human activities and agricultural development, the nitrogen content of groundwater in the Songnen Plain seriously exceeded the standard. To explore the status of nitrogen pollution and its effect on human health, this study employed shallow groundwater sampling test data, geostatistical analysis and conducted the triangular random model to assess the risk of nitrogen exposure in children and adults, and performed the uncertainty analysis. The results showed that: 1) The main nitrogen pollutants was nitrate nitrogen, and the sample exceeded the standard rate of 44.35%, and the maximum value reached 566.2 mg/l, and the region with a concentration of nitrate nitrogen greater than 20 mg/l accounts for about 60% of the total area in the region, mainly distributed in the high plain area of the eastern and central parts, and the western front slope plain is less polluted; 2) Based on the triangular fuzzy coupled stochastic model on the Isight5.9-2 platform, considering the impact of human activities and agricultural development, the study area is divided into different units. The analysis shows that the non-carcinogenic risk ranking is: evaluation unit III> evaluation unit II>evaluation unit I, and the contaminants in Unit III are mainly derived from agricultural activities, and the risks in Units III and II are much higher than the safety threshold value of 1, which may cause potential harm to children and adults, and threaten children more; 3) The uncertainty of pollutant concentration and parameters has a large fluctuation range for the risk value, and the triangular random model is more sensitive to data changes, which can reduce the uncertainty of the triangular fuzzy method. The unit I risk interval value crosses the safety threshold 1 ,and it may mislead pollution prevention and control decisions; the contribution rate of nitrate nitrogen concentration to risk is above 90%, which clarifies the necessity of random sampling, at the same time, the test error of nitrate nitrogen should be minimized and relevant data should be collected to improve the reliability of the evaluation results.
Key words:groundwater; nitrogen pollution; health risk assessment; uncertainty.