Exposure to air pollution can increase risk of premature death from heart or lung disease for more than 30 years, suggests one of the longest running air pollution studies.
British scientists, who found the long-term negative health effects of air pollution, said that the reliability of their findings stems from the very long follow-up time and the very detailed assessment of air pollution exposure, using data that in some cases went back to the early 1970s.
The researchers monitored air pollution levels in areas of England and Wales for nearly 40 years and estimated pollution levels in 1971, 1981, 1991 and 2001. From 1971 to 1991, the scientists measured levels of black smoke and sulfur dioxide air pollution. These types of pollution are primarily from burning fossil fuels, such as coal and oil.
In addition, the investigators measured particulate air pollution, or tiny particles in the air. This type of pollution is typically associated with natural sources, such as soil and sea salt, as well as industrial and construction activities. These miniscule particles can travel deep into the lungs, and may even be small enough to enter the bloodstream.
The researchers also tracked the health of 368,000 people living in the study areas. Lung diseases, such as bronchitis, emphysema and pneumonia, were the most likely to be tied to exposure to air pollution, as was death from heart disease, the study revealed.
The study results showed that for every additional unit of pollution per cubic meter of air that people inhaled in 1971, the risk of death between 2002 and 2009 increased by two percent.
Putting this in context, an individual who lived in a higher polluted area in 1971 had a 14 percent higher risk of dying in 2002 to 2009 than someone who had lived in a lower polluted area.
The study also showed that more recent air pollution exposure made a bigger difference on health. For each additional unit of pollution that people were exposed to in 2001, the risk of death between 2002 and 2009 increased by 24 percent, the findings showed.
However, the researchers added, air pollution's effects on one’s health were small compared to other lifestyle risk factors, including smoking, exercise levels, weight and medical conditions, such as high blood pressure. But the study did add weight to the growing evidence that breathing in air pollution is not good for us in either the short- or long-term.