Vaping weed is very popular, but users should be aware it carries risks : NPR

Vaping pot from an e-cigarette can be relatively odorless and discreet, compared to smoking dried marijuana flower. And because it is cooler, it may be a little easier on the lungs than smoking. But it is rife with chemicals whose safety profile is unknown. For the How Safe Is Your Weed Series. Yuki Noguchi/Diane Webber