I grew up in rural Colorado, deep in the mountains, and I can still remember the first time I visited Denver in the early 2000s. The city sits on the plain, skyscrapers rising and buildings extending ...

ATLANTA, GEORGIA - JUNE 25: Cars and trucks drive along Interstate 75/85 June 25, 2003 in Atlanta, Georgia. The first "Code Red" smog alert was of the year was announced with tailpipe and smokestack ...

While pollution outdoors poses a significant health risk for people, worsening indoor air quality has also gradually become a pressing issue that needs to be addressed. Annually, almost 4 million ...