Groundwater is an important source for domestic drinking, agriculture, and industrial activities. However, arsenic and nitrate contamination in groundwater are major world problem and public health concern. This research aimed to evaluate the concentration and spatial distribution of arsenic and nitrate in groundwater of 22 cultivated villages of Chahardoli Plain of Iran by geostatistical techniques and their possible health hazards in local residents. A total of 94 groundwater samples were collected from wells in agriculture areas and analyze for arsenic and nitrate concentrations. Geostatistical analysis and health risk assessment model were applied to investigate spatial distribution, and associated health risks of arsenic and nitrate in groundwater of the study area. The levels of nitrate in groundwater had a range of 3.20–428.00 mg/L with the mean value of 152.95 ± 115.49 μg/L. Nitrate concentration in 73% of samples exceeded the World Health Organization (WHO) acceptable limits of 50 mg/L. Arsenic (As) was found in groundwater which ranged from 0.39 to 220.82 μg/L (mean 30.16 μg/L) and exceeded the WHO recommended level (10 μg/L) for 59% of the groundwater samples. The health risk of nitrate indicated the Hazard quotient (HQ) values suggesting an unacceptable noncarcinogenic health risk. For arsenic, the mean values of HQ for a men, women, and children were.0.24 (0.04–1.54), 0.29 (0.05–1.85), and 0.65 (0.11–4.15), respectively. Generally, exposure to arsenic and nitrate via groundwater depicts that, children were at greater risk followed by women and men. Gold mining was also one of the proposed causes of elevated arsenic concentrations in the northern part of the plain. It can be concluded that in addition to the specific geology of the study area that has led to high concentrations of arsenic in the plain, the spatial distribution of arsenic revealed an increase in the northern part of the region that may be due to the presence of gold mine.

地下水是家庭饮用水、农业和工业活动的重要来源。然而，地下水中的砷和硝酸盐污染是主要的世界问题和公共卫生问题。本研究旨在通过地统计学技术评估伊朗恰哈多利平原 22 个耕地地下水中砷和硝酸盐的浓度和空间分布及其对当地居民的健康危害。从农业区的井中收集了总共 94 个地下水样品，并分析了砷和硝酸盐的浓度。应用地统计分析和健康风险评估模型，研究了研究区地下水中砷和硝酸盐的空间分布及相关健康风险。地下水中硝酸盐的含量范围为 3.20-428。00 mg/L，平均值为 152.95 ± 115.49 μg/L。73% 样品中的硝酸盐浓度超过了世界卫生组织 (WHO) 可接受的 50 mg/L 限值。地下水中的砷 (As) 含量范围为 0.39 至 220.82 微克/升（平均 30.16 微克/升），超过 59% 的地下水样本的世界卫生组织推荐水平（10 微克/升）。硝酸盐的健康风险表明危害商 (HQ) 值表明不可接受的非致癌健康风险。对于砷，男性、女性和儿童的 HQ 平均值分别为 0.24（0.04-1.54）、0.29（0.05-1.85）和 0.65（0.11-4.15）。一般来说，通过地下水接触砷和硝酸盐表明，儿童面临更大的风险，其次是女性和男性。金矿开采也是导致平原北部砷浓度升高的原因之一。可以得出结论，除了研究区的特定地质导致平原砷浓度较高外，砷的空间分布揭示了该地区北部砷的增加可能是由于存在金矿。