It has long been established that the air we breathe is essential to keep us alive. Oxygen is necessary for all of the body's processes. However, with changes to climate and increases in air pollution abounding, how dangerous is our vital air becoming?

Air pollutants are variable. They can be gases, like carbon monoxide or ozone, as well as fine particulate matter, which can be made up of anything. According to the Environmental Protection Agency (EPA), particulate matter can be made up of acids, chemicals, metals, soil or dust particles, and other toxins that should not enter our bodies but can if they are in the air. While we cannot see this matter in the air, we do inhale trace amounts of it, and eventually those amounts can build up to dangerous levels.

A new study has found that air pollution causes thousands of premature deaths, thanks to respiratory issues. Shockingly, researchers, by the use of models to estimate how air pollution affects health, found that 2.1 million premature deaths occur globally each year because of increases in air pollution caused by humans. The researchers indicate that particulate matter alone is related to 93 percent of cardiovascular diseases, such as high blood pressure, heart attacks, strokes, and atherosclerosis, along with seven percent of lung cancer occurrences.

The two forms of pollution focused on in this study were particulate matter and ozone. Particulate matter enters the air when materials are not disposed of properly, or simply due to wind and humidity keeping the particles in the air instead of on the ground. Ozone is a dangerous gas, known to kill when it makes contact with cells like it does in the lungs. It is a key component of smog, and long-term exposure to it can be highly dangerous, according to the EPA. The researchers indicate that lately, we are emitting more of these kinds of pollutants than ever before, even at the dawn on the industrial age.

The researchers suggest that deaths caused by past changes to air pollution and climate were much lower than what they are now. They indicate that we are polluting the air so much now that the deaths caused by ozone have increased by nearly 400 times. Deaths caused by ozone in the air due to past changes in climate were measured to be 1,500 per year, but with models that project further pollution estimate that 470,000 deaths will occur related to the contaminant, thanks to the high rate at which we pollute our air.

The researchers explain that climate change is the reason for this sudden worsening in air pollution, as estimates regarding air pollution and related deaths only increase when climate change is factored in. Climate change affects air pollution in many ways, possibly leading to local increases or decreases in air pollution. For instance, temperature and humidity can change the formation or lifetime of a pollutant, and amount of rainfall can determine the time that pollutants can accumulate to cause severe health risks.

"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," said Jason West, Ph.D., co-author of the study.

Different countries have different levels of pollution. However, it is clear that the amount of air pollution currently measured is becoming out of control if it can be the cause of more than 2.1 million deaths. The researchers suggest that we find ways to reduce our emissions of air pollution while still considering our climate and how that can worsen current pollution's effect on health.

Source: Silva RA, West JJ, Zhang Y, et al. Global premature mortality due to anthropogenic outdoor air pollution and the contribution of past climate change. Environmental Research Letters. 2013.