Air pollution and neurodegenerative diseases have been linked in recent scientific studies. A new research added another argument that shows how pollution directly influences dementia. The study was conducted by 12 researchers who studied a group of seniors from Ontario, Canada , from 2001 to 2013.
Twelve years ago, experts selected a group of approximately 2.1 million people . The requirements for the selection were: that in 2001 they were between 55 and 85 years old, were born in the United States and were not diagnosed with dementia. In the information about the group an algorithm was applied to measure the incidence of pollution in the diagnoses of dementia. At the same time, their residences were studied in order to estimate the exposure in which they lived. Then cross these data with other factors such as diabetes, brain injury and neighborhood income.
The finding, published in the journal Environment International , warned that although Ontario is one of the least polluted cities in the world, its population is an invisible risk. During the twelve-year follow-up, researchers counted 257,816 cases of diagnosed dementia, of which 6.1% were directly attributed to environmental contamination. The main sources of pollution were finer particulate matter ( PM 2.5 ) and nitrogen dioxide .