The invisibility of health effects associated with water pollution within disease burden estimates: Analysis from a Colombian Andean watershed

Modernization is marked by an increase in pollution-related health risks due to the rapid economic and technological growth. In the Global South, there is concern regarding the disease burden attributable to chemical contaminants released into the environment, especially in river basins, where populations are exposed through multiple pathways. While significant research exists linking chemical exposure to disease, mostly in occupational settings, less data is available for the open environment. Emerging pollutants have shown ecotoxicological and genotoxic effects at low concentrations in both terrestrial and aquatic ecosystems, with humans at the apex. Despite such evidence, water quality standards focus primarily on communicable diseases risks, and the burden of disease method mainly includes gastrointestinal and respiratory infections. Therefore, the use of DALYs as a prioritization strategy needs to be evaluated to suggest alternatives for integrated analysis. Our aim was to enhance the comprehension of watersheds as socioecological entities that necessitate inclusive indicators to display the intricate and diverse links between water, health, and the resultant inequities. Based on previous research and information collected in a tropical Andean watershed at southwestern Colombia, we characterized drivers of pollution and health hazards. Using standardized methods for calculating DALYs, we estimated the water-related environmental burden of communicable and noncommunicable diseases. Estimates of disease burden were analyzed to find out disparities driven by ethnic, gender and socioeconomic status. Results indicate that significant inequalities persist affecting the most vulnerable populations for preventable communicable diseases. Furthermore, the impact of noncommunicable diseases, which are linked to chemical pollution from individual substances and their cocktail effect, remains largely invisible due to insufficient data and research. The econometric approach of the DALY addition effect needs to be expanded with historical and critical perspectives to expose the profound social and health inequities present in the socioecological systems of the Global South.