Dietary Exposure of Arsenic Due to Mining Activities and the Plight to Human Health: an Assessment Through Multimodal Statistical Approaches

This study aims to investigate the potential risk of As contamination in rice cultivated in agricultural fields affected by mica mining in Jharkhand, India. For this purpose, soil and rice grain samples were collected from the agricultural fields 500 m (Zone 1) and 50 m (Zone 2) from the mica mines. Total As (mean +/- SD) content in the Zone 1 and Zone 2 were 4.79 +/- 0.11 and 44.74 +/- 1.01 mg kg(-1), respectively. The available As was of 3.76 +/- 0.22 mg kg(-1) in Zone 1 and 1.55 +/- 0.02 mg kg(-1) in Zone 2. The As in rice grain varied from 1.09 +/- 0.08 mg kg(-1) in Zone 2 to 0.11 +/- 0.02 in Zone 1. From sequential extraction the concentration of As in Zone 2 followed the order: amorphous (14.59 mg kg(-1)) > crystalline iron oxide-bound phases (6.27 mg kg(-1)) > exchangeable fraction (0.62 mg kg(-1)) > water-soluble (0.15 mg kg(-1)). Amorphous iron oxide bound As have significant (p < 0.05) positive correlation with As in rice plant parts. From self-organizing map and positive matrix factorization analysis, mining activities and improper disposal of mica mining waste were recognized as significant contributors to As toxicity in the region. The measured total cancer risk for children, men and women were 3.10 x 10(-2), 7.7 x 10(-3) and 8.4 x 10(-3), respectively, exceeding the tolerable limit of 10(-5). The hazard index values were below toxic thresholds, children experienced the highest impact, followed by women and men.