Household contributions to and impacts from air pollution in India

A quantification of PM2.5 pollution finds that mortality risk lies disproportionately within low-income households, and that addressing their indoor air pollution sources can avert more absolute deaths, yet wealthier individuals are more responsible for the emissions. Airborne fine particulate matter (PM2.5) is the largest environmental risk factor for premature mortality worldwide, and the probable cause of several hundred thousand premature deaths every year in India. Indian households contribute to ambient PM2.5 directly from several sources, including biomass-burning cook stoves and transport, and indirectly through the manufacturing of products triggered by their purchases. Here, we quantify consumption-based PM2.5 contributions from, as well as the mortality burden suffered by, urban and rural households by income deciles. Indirect PM2.5 emissions contribute almost twice as much to ambient PM2.5 concentrations as direct emissions from biomass cook stoves. We find that the impacts are distributed differently from contributions. We show that the mortality risk from indirect sources falls disproportionately on lower-income households. This suggests that industry-wide pollution controls can reduce inequity in the impacts of ambient air pollution. However, as low-income households face an order of magnitude higher mortality risks from indoor air pollution, clean cooking fuels remain the most effective way to reduce the number of premature deaths from air pollution in India.