Cumulative effect of PM(2.5) components is larger than the effect of PM(2.5) mass on child health in India

While studies on ambient fine particulate matter (PM(2.5)) exposure effect on child health are available, the differential effects, if any, of exposure to PM(2.5) species are unexplored in lower and middle-income countries. Using multiple logistic regression, we showed that for every 10 μg m(−3) increase in PM(2.5) exposure, anaemia, acute respiratory infection, and low birth weight prevalence increase by 10% (95% uncertainty interval, UI: 9–11), 11% (8–13), and 5% (4–6), respectively, among children in India. NO(3)(-), elemental carbon, and NH(4)(+) were more associated with the three health outcomes than other PM(2.5) species. We found that the total PM(2.5) mass as a surrogate marker for air pollution exposure could substantially underestimate the true composite impact of different components of PM(2.5). Our findings provide key indigenous evidence to prioritize control strategies for reducing exposure to more toxic species for greater child health benefits in India.