(CBS) Scented laundry detergent and dryer sheets make laundry smell great - but do they cause cancer?
A small study suggests scented laundry items contain carcinogens that waft through vents, potentially raising cancer risk.
"This is an interesting source of pollution because emissions from dryer vents are essentially unregulated," said lead author Dr. Anne Steinemann, professor of civil and environmental engineering and of public affairs at the University of Washington, said in a written statement. "If they're coming out of a smokestack or tail pipe, they're regulated, but if they're coming out of a dryer vent, they're not."
Previous studies have looked at what chemicals are released by laundry products, since manufacturers don't have to disclose ingredients used in fragrances or laundry products.
Needless to say, these researchers weren't thrilled with what they found.
For the study - published in the August issue of Air Quality, Atmosphere and Health - researchers enlisted two homeowners to volunteer their washers and dryers, which the team scrubbed clean beforehand. The researchers ran a regular laundry cycle for three scenarios in each home: once without any detergent, once with a scented liquid laundry detergent, and the last with both scented detergent and a leading brand of scented dryer sheets.
Their analysis found more than 25 "volatile" air pollutants - including the carcinogens acetaldehyde and benzene.
Benzene causes leukemia and other blood cancers, according to the American Cancer Society. Acetaldehyde has been shown to cause nasal and throat cancer in animal studies.
Steinemann thinks agencies focus too much on limiting other pollution sources when they should look closer to home.
"We focus a lot of attention on how to reduce emissions of pollutants from automobiles," she said. "And here's one source of pollutants that could be reduced."
The American Cleaning Institute, however, Steinemann's study, calling the findings "shoddy science" that didn't take into account many factors like washing machine brands, different load cycles, and non-scented products.
"Consumers should not be swayed by the sensationalist headlines that may come across the Internet related to this so-called research," the Institute emailed CBS News.