Toxicologie environnementale et analytique

Toxicity Due to Arsenic in Gangetic Zone of Patna, India and Its Linkage with Cancer

Abstract

Akhileshwari Nath, Priyanka S E Vendan, Shailendra Kumar, Arun Kumar and J K Singh

Arsenic (As), a well-known environmental toxicant naturally found in rocks in the earth’s crust contaminates groundwater. Patna, a highly populated district of Bihar, India, is situated on the banks of the river Ganges in the area commonly referred to as the Gangetic-Zone. The entire district of Patna is divided into 23 blocks. The purpose of this study was to assess the concentration of As in drinking water and blood samples of people residing in different blocks of Patna.

Drinking water and blood samples were collected from all 23 blocks of Patna. Estimation of As in water samples was done using Arsenic Kit. The observed value was further validated using Atomic Absorption Spectrophotometry with Vapor Generation Assembly (AAS-VGA). More than 50 ppb of As was observed in drinking water samples of 15 blocks (Athmalgola, Bakhtiyarpur, Barh, Belchhi, Bikram, Bihta, Daniyawan, Dulhin Bazaar, Fatuha, Ghoswari, Khusrupur, Maner, Mokama, Paliganj and Pandarakh). A concentration of more than100 ppb of As was detected in the samples from Danapur and Naubatpur, which is more than10 times the WHO permissible limit of 10 ppb. Sample population exhibited high incidence of cancers of various organs such as skin, breast, liver, and gall bladder. Nodular keratosis on palm and sole of the affected population was also observed. As contamination was not observed in the blood samples of healthy people included in the study.

The study showed that surveyed population of blocks of Patna district with high As accumulation in groundwater had a high accumulation of As in their blood samples. High incidence of cancers of skin, liver, breast and gall bladder was also observed in these blocks. The study therefore demonstrates a high degree of correlation between elevated groundwater As concentration and high As concentration in blood stream of persons affected by cancer. The study further concludes that As accumulation is one of the factors causing high rate of cancer in affected areas.