Your favorite laundry products and air fresheners could be emitting a lot more than just a ‘fresh scent’, according to a University of Washington study.

Researchers analyzed a range of top-selling products from plug-in oils to dryer sheets, fabric softeners and detergents. What they found was that all of them contained dozens of different chemicals. In fact, researchers said all six products tested gave off at least one chemical regulated as toxic or hazardous under federal laws.

"I was surprised by both the number and the potential toxicity of the chemicals that were found," said Anne Steinemann, a University of Washington professor, in a news release. “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.”

VIDEO: Click here to learn more about dangerous everyday frangrances.

In the laboratory, each product was placed in an isolated space at room temperature and the surrounding air was analyzed for chemicals.

Results showed 58 different volatile organic compounds above a concentration of 300 micrograms per cubic meter. For example, a plug-in air freshener contained more than 20 different volatile organic compounds. Of these, seven are regulated as toxic or hazardous under federal laws.

Steinemann had this advice for consumers.

"Be careful if you buy products with fragrance, because you really don't know what's in them," she said. "I'd like to see better labeling. In the meantime, I'd recommend that instead of air fresheners people use ventilation, and with laundry products, choose fragrance-free versions."

The study is published online by the journal Environmental Impact Assessment Review.