Air pollution kills over 2 million a year, says new study

Outdoor, man-created air pollution could be responsible for over 2.5 million deaths a year, according to a new study. The research, published in the Environmental Research letters Journal, highlights that particulate matter and ozone are the biggest culprits of air pollution related fatalities.

The study, entitled 'Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change', suggests that around 2.1 million people worldwide die as a result of fine particulate matter, more precisely particulates of up to 2.5 micrometres wide (PM2.5). This form of air pollution is caused by the burning of certain fossil fuels, such as coal, and from diesel exhausts. PM2.5 pollution has been linked to heart disease and lung cancer by previous studies.

It has also been suggested by the study that around 470,000 people worldwide die due to exposure from ozone pollution. Ozone is a very unstable molecule that is highly toxic even at low levels. Unlike the stratospheric ozone, it is man-made. It is created when nitrogen dioxide, released from combustible engines, reacts with oxygen and is more prevalent in city areas with higher temperatures.

Jason West, co-author of the study, said: "Our estimates make outdoor air pollution among the most important environmental risk factors for health.  Many of these deaths are estimated to occur in East Asia and South Asia, where population is high and air pollution is severe."

The estimated death counts related to air pollution were determined by comparing the new research to previous mathematical models on air pollution induced fatalities. The surprising result was that the estimates that were then calculated were lower than the researchers' original figures. However, the research team suggests that both the final figures and their pre-comparison results are both likely to underestimate the true result of air pollution on human health due to the fact the study only assessed those aged 30 and older and because the use of different climate models within the research altered the estimated figures.

Mr West continued: “We have also found that there is significant uncertainty based on the spread among different atmospheric models. This would caution against using a single model in the future, as some studies have done”.