Lead exposure in Bihar, Eastern India: a risk assessment study

An estimated 800 million people globally are reported to be suffering from lead poisoning. In India, lead exposure has affected many states such as Andhra Pradesh, Uttar Pradesh, Jharkhand, Madhya Pradesh, and Chhattisgarh. The current research study has been conducted in various districts for Bihar such as Patna, Vaishali, Saran, Nalanda, Buxar and Bhojpur for the first time to estimate the lead exposure levels in subjects. The study was conducted on n = 282 lactating mothers and their breastfed infants. In the studied n = 282 lactating mother's blood samples, 94% had lead contamination higher than the WHO permissible limit of 50 µg/L. In the lactating mother's urine samples, 90% had lead contamination higher than the WHO permissible limit of 50 µg/L. Similarly, in the child's urine study, 41% had lead contamination higher than the WHO permissible limit of 50 µg/L. However, the analysed household handpump water also had lead contamination in 6% of the water sources more than the WHO permissible limit of 10 µg/L, while 94% of water sources had safer levels. This indicates that the source of lead contamination in biological samples of the studied subjects was mildly due to lead contaminated water. Hence, food, vegetables, animal milk or animal meat could be the source of lead contamination in the exposed subjects. Moreover, this could also be due to the use of local market turmeric, use of ayurvedic medicines, cosmetic - whitening creams by the exposed subjects. The long-term exposure to lead has caused non-carcinogenic HQ higher values i.e. > 1 in child and their mothers. Hence, the current study concludes that significant amount of lead contamination was observed in the exposed population's biological samples. The exposed lactating mother's breastfed infants are at high risk of developing neurological disorders which could cause severe health risk to them. The study recommends the state Government to take preventive measures to control the lead poisoning within the exposed community of Bihar (India).