Je re-ouvre ce topic pour ne pas creer une enieme discussion sur la pollution, mais j'ai trouve cet article (en Anglais) interessant... J'ai enetendu plusieurs theorie sur les effets a long terme de la pollution, don't une qui dit que notre systeme se nettoie quand il n'y est plus expose.. mais cette etude dit le contraire - inquietant..
Exposure to air pollution 30 years ago associated with increased risk of death
Exposure to air pollution more than 30 years ago may still affect an individual's mortality risk today, according to new research from Imperial College London.
The new report comes from one of the world's longest running air pollution studies, which included 368,000 people in England and Wales followed over a 38 year period. The team, from the MRC-PHE Centre for Environment and Health, estimated air pollution levels in the areas where the individuals lived in 1971, 1981, 1991 and 2001, using measurements from Britain's extensive historic air pollution monitoring networks.
Highest risks were seen for respiratory disease, such as bronchitis, emphysema and for pneumonia. Air pollution also affected mortality risk from cardiovascular diseases, such as heart disease.
We were surprised to find pollution has effects on mortality that persist over three decades after exposure
– Dr Anna Hansell
Dr Anna Hansell, lead author of the study, from the MRC-PHE Centre for Environment and Health at Imperial, said: "Air pollution has well established impacts on health, especially on heart and lung disease. The novel aspects of our study are the very long follow-up time and the very detailed assessment of air pollution exposure, using air quality measurements going back to the 1970s.
"Our study found more recent exposures were more important for mortality risk than historic exposures, but we need to do more work on how air pollution affects health over a person's entire lifetime.
"We were surprised to find pollution has effects on mortality that persist over three decades after exposure."
In the study, published in the journal Thorax, the researchers assessed levels of black smoke and sulphur dioxide air pollution from 1971 to 1991 and PM10 air pollution in 2001. Both black smoke and PM10 are measures of small particles in the air. Black smoke and sulphur dioxide were produced mainly by burning fossil fuels, including coal, oil, diesel, petrol.
Today, the methods of measuring air pollution have changed. A common measure is PM10, which measures very small particles that are less than 10 microns in size. These can travel deep into the lungs and may even be small enough to enter the bloodstream. This type of air pollution is mainly produced by transport and industry with a contribution from construction activities and natural sources, for example sea salt and soil.
Dr Rebecca Ghosh, co-author of the study from the School of Public Health at Imperial, said "Putting this in context, an individual who lived in a higher polluted area in 1971 had a 14 per cent higher risk of dying in 2002 to 2009 than someone who had lived in a lower polluted area. An individual living in a higher polluted area in 2001 also had an increased risk of mortality of 14 per cent compared to someone in a low pollution area.
