Drinking water survey to elucidate risk factors in a region with high incidence of gallbladder cancer in India

Abstract

People living near the Ganges River Basin located in northern India show a high incidence of gallbladder cancer, but the onset mechanism for this cancer in this region has not been well defined. Therefore, we conducted a drinking water survey of people living in this region to obtain clues regarding the causes of gallbladder cancer. Samples of Ganges River water, public tap water, public well water from two spots, and well water from four gallbladder cancer patients’ homes were collected in September 2017. Lead levels, bacterial counts, levels of agricultural chemicals, iron, copper, nitrate, nitrite, and chlorine, pH, and hardness were measured using a simple commercial water analysis test kit. The results obtained were then compared with the water quality standards for drinking water in Japan. Of the 10 items, bacteria, iron, and nitrate were present at levels beyond the standard levels. Additionally, three of the four well water samples collected from gallbladder cancer patients’ homes were contaminated with bacteria, and two had iron levels higher than the standard levels. Additional research is needed to clarify whether bacteria in the home well water of gallbladder cancer patients are related to gallbladder cancer risk.