A comparative hydrogeochemical study evaluated arsenic release mechanism and differences in contamination levels in the shallow groundwater of two areas within the deltaic environment of West Bengal (i.e. Karimpur and Tehatta blocks of Nadia district) in India. Groundwaters from both the areas are Ca-Na(K)-Cl-HCO₃ type with highly reducing character (−110.16 ± 16.85 to −60.77 ± 16.93 mV). Low correlations among As, Fe, and Mn and the higher association between As and DOC are indicative of microbial decomposition of organic matter enhancing the weathering of shallow aquifer materials. Arsenic contamination in groundwater is higher in Karimpur (95 ± 81.17 μg/L) than that in Tehatta (43.05 ± 41.06 μg/L). The release mechanism of arsenic into groundwater is very complex. Low Fe (0.27–4.78 mg/L and 0.81–4.13 mg/L), Mn (0.08–0.2 mg/L and 0.03–0.22 mg/L), and SO₄²⁻ (3.82 ± 0.31 and 2.78 ± 0.40 mg/L) suggest that the mechanism of arsenic release is not a single mechanistic pathway. Clustering of redox-active parameters in the principal component planes indicate that the reductive dissolution, and/or weathering/co-precipitation of Fe/Mn-bearing minerals in the shallow aquifer sediments control the dominant mechanistic pathway of arsenic release.

一项比较水文地球化学研究评估了印度西孟加拉邦三角洲环境中两个地区（即纳迪亚地区的卡里姆布尔和特哈塔地块）的浅层地下水中砷的释放机理和污染物水平的差异。这两个地区的地下水都是Ca-Na（K）-Cl-HCO ₃具有高度降低特性的类型（−110.16±16.85至−60.77±16.93 mV）。As，Fe和Mn之间的相关性较低，而As和DOC之间的相关性较高，表明有机物发生了微生物分解，从而增强了浅层含水层材料的耐候性。Karimpur（95±81.17μg/ L）地下水中的砷污染高于Tehatta（43.05±41.06μg/ L）。砷释放到地下水中的机制非常复杂。低铁（0.27–4.78 mg / L和0.81–4.13 mg / L），锰（0.08–0.2 mg / L和0.03–0.22 mg / L）和SO ₄ ^2-（3.82±0.31和2.78±0.40 mg / L）表明砷释放的机制不是单一的机械途径。氧化还原活性参数在主成分平面中的聚类表明，浅层含水层沉积物中含铁/锰的矿物的还原溶解和/或风化/共沉淀控制着砷释放的主要机理。