What kills more than two million people a year?  The answer is air pollution, considered to be the ultimate lifestyle-induced health problem.

We all know air pollution is bad, but how exactly does it cause death? This happens when fine particulate matter in the air gets into the tissue of the lungs and causes respiratory illnesses and even cancer. Increased ozone levels are responsible for a further 470,000 deaths each year. Most of these deaths happen in South and East Asia, where the population and air pollution levels are both very elevated.

Environmental Research Letters published these results from a study earlier this month. Using a total of twenty different climate models, researchers simulated concentrations of ozone and fine particulate matter between 1850 and 2000. The study chose 1850 as the starting point for their research to represent the beginning of the industrial age. The twenty different atmospheric models showed somewhat different results, which although inconclusive, does caution against any past or future studies that use only one model.

A lot of information is needed to create an atmospheric model, especially one representing a specific time in the past. One way to try to understand the atmospheric conditions of times past is to look at previous epidemiological studies. These can show the relationship of concentrations of air pollution to global deaths.

Where does climate change fit in to all this? Not as much as air pollution itself. Climate change is responsible for just 1,500 ozone-related deaths and 2,200 fine particulate matter deaths per year. Climate change has only a small effect on air pollution and increased related deaths. It can affect air pollution in a couple of different ways. For example, higher temperatures cause trees to emit more organic compounds, which react in the atmosphere to form ozone and fine particulate matter. Changes in rainfall can also change the way or locations of pollutant accumulation.

Read the entire article here: 2 Million Deaths a Year Could Be Due to Air Pollution: Study