7 Surprising Triggers of Lung Trouble

Candles

A recent study by researchers at South Carolina State University found that paraffin-based candles—the most popular kind of candle—emit toluene and benzene. (Candles made from beeswax and soybean, which the researchers also studied, do not produce these chemicals.)

Lighting paraffin candles for the occasional romantic dinner doesn’t pose a health threat (if you don't count fire). But when used often in unventilated spaces, candles may aggravate asthma.

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