The amount of Americans who are exposed to secondhand smoke has decreased by nearly half in the past 12 years, reports the CDC.

The decline— from 53 percent in 2000 to 25 percent in 2012—is due to many cities and states banning cigarettes in public areas, which has also led smoking to become increasingly less socially accepted.

But secondhand smoke is not entirely a thing of the past—1 in 4 nonsmokers (or 58 million Americans) are still being exposed to these harmful chemicals.

And even more alarming is this statistic: 2 in 5 children, between the ages of 3 and 11, are still exposed to secondhand smoke, according to the Centers for Disease Control and Prevention. Experts also estimate that secondhand smoke has caused more than 400 infants to die from SIDS each year.

"Children are often exposed to smoke in their homes, and the report speculated that the sluggish decline in exposure of children might have to do with the fact that the fall in the adult smoking rate has slowed,"  reports The New York Times.

Infants and children are dependent on others to keep them out of harm's way, so avoid smoking and exposing them to secondhand smoke at all costs—especially if they suffer from asthma—and everyone will be healthier as a result.

Caitlin St John is an Editorial Assistant for who splits her time between New York City and her hometown on Long Island. She's a self-proclaimed foodie who loves dancing and anything to do with her baby nephew. Follow her on Twitter: @CAITYstjohn

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