Anne Steinemann, a University of Washington professor of civil and environmental engineering, says she analyzed the products to discover the chemicals' identity.

"I first got interested in this topic because people were telling me that the air fresheners in public restrooms and the scent from laundry products vented outdoors were making them sick," Steinemann said in a statement. "And I wanted to know, 'What's in these products that is causing these effects?'"

The study, published online by the journal Environmental Impact Assessment Review, found nearly 100 volatile organic compounds were emitted from these six products, and none were listed on any product label. Five of the six products emitted one or more carcinogenic "hazardous air pollutants," which are considered by the U.S. Environmental Protection Agency to have no safe exposure level, the study said.

"I was surprised by both the number and the potential toxicity of the chemicals that were found," Steinemann said.

Chemicals included acetone, the active ingredient in paint thinner and nail-polish remover; limonene, a molecule with a citrus scent; and acetaldehyde, chloromethane and 1,4-dioxane, Steinemann said.