High Cadmium Contamination in the Biological Samples of the Exposed Subjects in the Kosi Plain Region of Bihar

Abstract

The persistent nature of cadmium in the environment and its extensive industrial usage makes it a major threat to human health across the world. Cadmium is a human carcinogen because of its extreme toxicity and the fact that it affects many different organ systems. The present study was carried out in three districts of Kosi plain region of Bihar - Madhepura, Saharsa, and Supaul. A total of n = 60 lactating women voluntarily participated in the study after obtaining the written informed consent. Their biological samples such as blood, breastmilk, urine samples were collected for cadmium contamination study. Moreover, their household water and food samples such as rice, wheat and pulse were also collected for cadmium contamination study. Analysis revealed that 16.66% of the water samples exceeded permissible cadmium levels, whereas food samples, particularly rice, wheat, and pulses, exhibited significant cadmium contamination, highlighting dietary sources as a major route of exposure. In the analyzed biological samples, 100% of blood samples exhibited cadmium concentrations exceeding the WHO permissible limit (< 1.2 µg/L). Likewise, all lactating mothers had breast milk cadmium levels above the WHO permissible limit (< 1.0 µg/L), while 83% of urine samples also surpassed the WHO threshold (< 5.0 µg/L). These findings indicate that mothers exposed to cadmium in the Kosi plain region are transferring this toxic metal through breast milk to their infants, posing potential health hazards. Prolonged exposure in early life may result in gastrointestinal disturbances and impaired renal function, underscoring the critical risk to infant health. The potential health risks average daily dose (ADD) for the infants are higher than their lactating mothers. These findings highlight the urgent need for medical interventions in the Kosi plain region to address the prevailing cadmium poisoning problem. Moreover, a more comprehensive and systematic assessment of cadmium exposure across all districts of Bihar is required for better understanding the magnitude of the risk and to guide targeted public health strategies.