Environmental Arsenic Contamination and Human Health Risk Assessment in the Kosi Plain Region of Bihar, India

Abstract

Groundwater arsenic poisoning in the recent times has caused serious health hazards to the exposed population of Bihar. The arsenic causing disease burden in the Gangetic plains of Bihar has been well documented. But the present study aims to find out the arsenic exposure in the Kosi River plain region of Bihar for the first time. This study investigates arsenic exposure through breastfeeding among children in Bihar’s Kosi region -Madhepura, Saharsa, Supaul, Katihar districts while Bhagalpur and Nalanda in the Gangetic plain region where groundwater arsenic poisoning poses severe health risks. From a cohort of n = 312 lactating women, breast milk, blood, and urine samples, along with urine samples from n = 101 breastfed infants, were analyzed. Results show 25.3% of breast milk samples exceeded the WHO limit of 0.64 µg/L, with elevated levels also in maternal blood and urine samples. Infant’s urine indicated 2% above the permissible limit (< 50 µg/L). The multivariate study reveals a moderate to strong correlation between water arsenic levels and arsenic accumulation in rice. As water arsenic contamination increases, rice arsenic content also increases, indicating a significant uptake from irrigation. This underscores the role of rice as a major dietary source of arsenic in the studied area. The Monte Carlo simulation study shows the exceeding carcinogenic risk assessment in the rice samples as 79.94% in comparison to the breastmilk samples 1.73%. In conclusion, additional research in the Kosi region is imperative to thoroughly tackle this health challenge, with far-reaching implications for the well-being of future generations.