Wednesday, July 17, 2013

New Study - Global Premature Mortality due to Anthropogenic Outdoor Air Pollution and the Contribution of Past Climate Change

Published in Environmental Research Letters


Increased concentrations of ozone and fine particulate matter (PM2.5) since pre-industrial times reflect increased emissions, but also contributions of past climate change. Here we use modeled concentrations from an ensemble of chemistry–climate models to estimate the global burden of anthropogenic outdoor air pollution on present-day premature human mortality, and the component of that burden attributable to past climate change. Using simulated concentrations for 2000 and 1850 and concentration–response functions (CRFs), we estimate that, at present, 470 000 (95% confidence interval, 140 000 to 900 000) premature respiratory deaths are associated globally and annually with anthropogenic ozone, and 2.1 (1.3 to 3.0) million deaths with anthropogenic PM2.5-related cardiopulmonary diseases (93%) and lung cancer (7%). These estimates are smaller than ones from previous studies because we use modeled 1850 air pollution rather than a counterfactual low concentration, and because of different emissions. Uncertainty in CRFs contributes more to overall uncertainty than the spread of model results. Mortality attributed to the effects of past climate change on air quality is considerably smaller than the global burden: 1500 (−20 000 to 27 000) deaths/year due to ozone and 2200 (−350 000 to 140 000) due to PM2.5. The small multi-model means are coincidental, as there are larger ranges of results for individual models, reflected in the large uncertainties, with some models suggesting that past climate change has reduced air pollution mortality.


From CNN coverage

An estimated 2.1 million deaths are caused by anthropogenic increases of fine particulate matter (PM2.5) while a further 470,000 are killed annually as a result of human-caused increases in ozone pollution.

Jason West, co-author of the study published in the journal of Environmental Research Letters said: "Outdoor air pollution is an important problem and among the most important environmental risk factors for health."

East Asia is the worst affected area with researchers estimating more than a million people dying prematurely every year from PM2.5 pollution and 203,000 from ozone pollution.

India has the second highest air pollution mortality rates with an estimated 397,000 deaths from fine particulates and ozone accounting for, on average, 118,000.

Next comes Southeast Asia which has estimated average of 158,000 deaths from PM2.5 and 33,300 attributed to ozone.

Europe has fractionally less PM2.5 deaths (154,000, on average) and 32,800 premature deaths related to ozone while in North America there were an average of 43,000 deaths from fine particulates and 34,400 related to ozone.

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