Heat Waves Are Bad For (Even The Healthiest) Lungs

It's been the hottest summer on record in many cities on the East Coast -- and the hot days that keep coming could be dangerous. Ozone and fine particles are the two types of pollution that trigger Code Red and Orange days. Both are formed out of exhaust from power plants, cars and other things. And when people breathe in the chemicals, it irritates their lungs.

Avril Lavigne Bali Rodriguez Bar Refaeli