Foundation With Side Effects

NARS Firming Foundation Liquid

Oxybenzone can be a double-edged ingredient, protecting against UV rays but also causing irritation or triggering allergic reactions to light in some cases. The chemical can also be absorbed by skin, and 97 percent of Americans have built up some amount in their bodies, according to the U.S. Centers for Disease Control & Prevention.

"The way we're being exposed to chemicals every day is really concerning," Malkan said. "The one thing we can absolutely do something about is what we put on our bodies."

There are about 10,500 ingredients used in personal care products, according to the Environmental Working Group. Just 13 percent of the ingredients have been safety-tested, by an industry panel, over the past 30 years.