Mapping Arsenic Contamination and Health Risk Assessment of Arsenic in Agricultural Soils of Eastern India

Arsenic (As) pollution in soil poses a significant risk to human health and sustainable development goals. Accurate measurement of the degree of As contamination and mapping in soil are important for identifying high-risk areas and developing remediation strategies. In this study, 201 soil samples (0–15 cm) were collected from As contaminated rice growing regions in Nadia, West Bengal, India. Various pollution indices (geoaccumulation index, Igeo; contamination factor, CF; ecological risk index, Eri) were computed to understand the contamination level and its health implications. Geostatistical analysis using ArcGIS mapped the spatial distribution of As contamination in soil. The accuracy of different interpolation techniques were evaluated using root mean square error (RMSE) and mean CV (cross-validation) parameters. Results showed that total As content in soil ranged from 3.47 to 53.1 mg kg^‒1 (mean-19.3 mg kg^‒1). The pollution indices such as Igeo, CF, and Eri varied from ‒0.22 to 3.72 (mean-2.11 mg kg^‒1), 0.23 to 3.54 (mean-1.29 mg kg^‒1), and 2.32 to 35.4 (mean-12.9 mg kg^‒1), respectively. The northern side of Nadia showed higher As contamination, while comparatively lower levels were observed in southern side. Two interpolation techniques, viz. ordinary kriging (OK) and inverse distance weighting (IDW) were identified to precisely predict the spatial distribution of As in soil based on RMSE and mean CV values. Health risk assessment showed that children were more vulnerable to As toxicity in the study region. The findings support the development of location-specific remediation strategies and policies to minimize health risks associated with As-contaminated soils.