It started with dogs: a neuroscientist noticed that aging dogs in polluted areas of Mexico City often grew confused, disoriented, and forgetful. Since then, evidence has grown that breathing polluted air may be bad for the brain—perhaps even increasing the risk of dementia in humans. For example, a recent study from the University of Toronto found that people in Ontario who lived within 50 meters of a major road were 12% more likely to get dementia than those who lived 200 or more meters away. There is more research to be done to figure out exactly what’s going on and if there are any safe levels of polluted air.

More details here at the Sciencemag.orgAir-Pollution-Impacts-Brain-Health-1

對此問題的關注,是由一個狗隻研究結果開始的。一名神經學家發現,在墨西哥城污染地區的高齡狗隻變得混亂、健忘,辨別方向能力也有所減弱。其後,越來越多證據顯示,吸入受污染空氣可能對大腦有害 — 甚至可能增加人類患上癡呆症的風險。例如:多倫多大學最近的一項研究指出,住在公路50米範圍內的安太略居民,比住在距離公路200米或更遠範圍的居民,前者患上癡呆症的風險高出百分之十二。目前,仍有待開展更多的研究,去深入探討這個問題,並嘗試找出安全的空氣污染水平。