Arsenic groundwater contamination and its health effects in Patna district (capital of Bihar) in the middle Ganga plain, India

Abstract

We investigated the extent and severity of groundwater arsenic (As) contamination in five blocks in Patna district, Bihar, India along with As in biological samples and its health effects such as dermatological, neurological and obstetric outcome in some villages. We collected 1365 hand tube-well water samples and analyzed for As by the flow injection hydride generation atomic absorption spectrometer (FI-HG-AAS). We found 61% and 44% of the tube-wells had As above 10 and 50 μg/l, respectively, with maximum concentration of 1466 μg/l. Our medical team examined 712 villagers and registered 69 (9.7%) with arsenical skin lesions. Arsenical skin lesions were also observed in 9 children of 312 screened. We analyzed 176 biological samples (hair, nail and urine). Out of these, 69 people had arsenical skin lesions and rest without skin lesions. We found 100% of the biological samples had As above the normal levels (concentrations of As in hair, nail and urine of unexposed individuals usually ranges from 20 to 200 μg/kg, 20–500 μg/kg and <100 μg/l, respectively), indicating many people are sub-clinically affected. Arsenical neuropathy was observed in 40.5% of 37 arsenicosis patients with 73.3% prevalence for predominant sensory neuropathy and 26.7% for sensor-motor. Among patients, different clinical and electrophysiological neurological features and abnormal quantitative sensory perception thresholds were also noted. The study also found that As exposed women with severe skin lesions had adversely affected their pregnancies. People including children in the affected areas are in danger. To combat As situation in affected areas, villagers urgently need (a) provision of As-safe water for drinking and cooking, (b) awareness about the danger of As toxicity, and (c) nutritious food.