Fact-finding Analysis on Carcinogenic Compounds and Its Impact on Spurts of Cancer Cases in Bhavani River Basin, Tamil Nadu, India - Evidence-Based Research

Background: Toxic effluents from various industries, agricultural sectors, and domestic waste products released directly into the river systems act as promoters of carcinogenesis. Aim: The study aimed to identify the presence of carcinogens in the river Bhavani and determine their impact on the number of cancer cases in the Bhavani flowing districts of Tamil Nadu, namely Nilgiris and Erode. Materials and Method: Carcinogens were identified based on the "International Agency for Research on Cancer” lists of carcinogens with cancer sites. The concentration of potential carcinogens such as cadmium, hexavalent chromium, nickel, lead, arsenic, nitrite/nitrate, and phosphates are evaluated in Nilgiris and Erode through cross-sectional studies published from 2014 to 2020. Their levels were compared with the WHO standard limit for drinking water. Tamil Nadu Cancer Registry Project Report 2021 was used to calculate the percentage of cancer cases reported in each district contributing to the overall Tamil Nadu. Results: The results show that Nilgiris is slightly polluted with Nickel (0.062) and phosphates (0.925) that correspond to fewer number of cancer cases in the district compared to Tamil Nadu average status. As the river flows by Erode, the water gets highly contaminated with cadmium, chromium lead, and nickel more 1000 times the permissible limit and the results corresponds to elevated number of cancer cases compared to Nilgiris. Conclusion: A clear relationship exists between the number of cases reported and the concentration levels of carcinogenic compounds. Key words: Heavy metals, Cancer, Environmental pollution, Industrial effluents, Toxic elements, Water resources, Soil contamination, Carcinogenesis