Ambient fine particulate matter (PM2.5) is a major global risk for ill-health and premature death, resulting in ~3 million premature deaths per year. We combine ambient PM estimates from satellite observations and air quality models with epidemiological models to develop spatially-resolved estimates of the global health benefits that could result from cleaner air. We find that global improvements in ambient air quality could avoid millions of deaths each year, with major benefit to public health in clean and polluted countries alike.
Levels of particulate air pollution in New Delhi and in many other Indian cities substantially exceed domestic standards and international guidelines. We investigate the sources, concentrations, and exposures of air pollution in Indian cities in order to fill key data gaps and inform effective policies to protect public health. Current activities in India include (i) analysis of ambient concentration datasets, (ii) in-situ measurement of PM, and (iii) modeling of high-impact scenarios to mitigate this important environmental health hazard.
One important source of air pollution exposure for Delhi residents is time spent in vehicles: many commuters spend 1.5 - 2 hours each day in transit. We conducted an intensive field campaign to measure concentrations of fine, ultrafine, and black carbon particles inside cars and auto-rickshaws in New Delhi. Our measurements showed that particle concentrations in vehicles were 1.5 - 8 times higher than in ambient air. The measured concentrations are among the highest ever reported for a routine transportation microenvironment.
Intake fraction (iF) is a dimensionless parameter that quantifies the population exposure resulting from a unit of pollutant emissions. Intake fraction data are employed in life-cycle assessments and in health risk assessments, and can assist policymakers in setting emissions-control priorities. Among the major outdoor air pollution sources, urban vehicle emissions have especially high iF. In a recently completed project, we've estimated iF for vehicle emissions for 3600+ worldwide cities with a combined total of more than 2 billion inhabitants.