by Breathing in dirty air not only affects the lungs, but also increases the risk of developing a common type of brain tumor, as a study has determined.
Scientists analyzed several air pollutants, including those that are usually connected to traffic – such as nitrogen dioxide and ultra -fine particles that can often be found in urban environments.
The study published in the journal neurology It is more likely that people who are exposed to this type of pollution develop a meningioma – a typical not cancer -like brain tumor.
“It has been shown that different types of air pollution have negative effects on health, and ultra-fine particles are small enough to cross the blood-brain barrier and can directly influence the brain tissue,” said the study author Dr. Ulla Hvidtfeldt at the Danish Cancer Institute in Copenhagen.
“Our study suggests that long-term exposure to air pollution through traffic and other sources can play a role in the development of the meningioma, and increases the growing evidence that air pollution can influence the brain-not only the heart and lungs.”
This frequent type of brain tumor is formed in the lining of the brain and spinal cord.
Meningiomas are the most common type of primary brain tumor and, according to MacMillan, form around three primary brain and spinal cord tumors in adults in Great Britain.
However, the results do not prove that air pollution causes meningioma; They only show a connection between the two.
Data from almost 4 million adults in Denmark with an average age of 35 were included in the study.
The participants were followed over a period of 21 years. During this time 16,596 people developed a tumor of the central nervous system, including 4,645, which developed meningioma.
The use of house details and advanced modeling researchers were able to estimate the long-term exposure to air pollution and calculated an average 10-year exposure to certain pollutants.
The researchers examined the exposure to the following: Ultrafine particles with particles with a diameter of less than 0.1 micrometers; Fine -fine particles, also called PM2.5, with particles with 2.5 micrometers in diameter or less; Nitrogen dioxide, a gas mainly from traffic emissions; and elementary carbon, a marker for diesel pollution.
The people in the lowest group had an average 10-year exposure of 11,041 ultra-stones per centimeter (CM3) compared to people with the highest exposure of 21,715 particles/cm3.
Those with the lowest level of exposure were compared to people with the highest. The researchers were also adapted to factors such as age, gender and socio -economic status.
The results showed that people with a higher exposure to pollutants had a higher risk of meningioma.
For each increase of 5,747 particles/cm3 there was a higher risk of ultra -fine particles by 10 percent, a higher risk of fine particles for every increase of 4.0 micrograms per meter (μg/m3), a risk of 12 percent for each nitrog dioxide for each 8.3 & mgr; G/M3 and a 3 percent increase in elemental carbon carbon.
The researchers found no strong connection between these pollutants and more aggressive brain tumors.
