Depressed? Anxious? Air pollution could be among the reasons why, research finds

It’s well established that air pollution takes a serious toll on the human body, affecting almost every organ. (stock.adobe.com)

In the 1990s, residents of Mexico City noticed their dogs acting strangely. Some didn’t recognize their owners, and the animals’ sleep patterns had changed.

At the time, the sprawling, mountain-ringed city of more than 15 million people was known as the most polluted in the world, with a thick, constant haze of fossil-fuel pollution trapped by thermal inversions.