There Might Be a Scary Downside to Fabric Softener Sheets

Those wonderfully aromatic smells from your laundry may be a major source of home air pollution.

There are few scents as comforting as warm laundry pulled from the dryer, thanks to the olfactory magic of fabric softener sheets. They are simple enough products, nothing more than thin polyester sheets coated with chemicals to “soften” fabric fibers and give clothes that irresistible scent.

But have you ever wondered what's in those dryer sheets? Start by rubbing one sheet between your fingers. That waxy and slightly tacky feeling is a surfactant compound used to coat your clothes, keeping them soft. The surfactant compound is positively charged to help remove static from clothes in the dryer.

The surfactant is typically a fatty compound such as quaternary ammonium salt (which is linked to asthma), silicon oil, or stearic acid (derived from animal fat). Some dryer sheets may contain more than one surfactant. When these compounds heat up in the dryer, they liquefy and coat the clothes. In essence, your fabrics aren't any softer—they're just coated with a fatty compound to make you think they are.

Along with the surfactant — which may or may not be listed on the ingredients list — is a fragrance whose composition may also be obscured from the consumer. Those fragrances, found in sheets from brands such as Downy and Bounce, may pose health risks, as the toxins they're made with transfer to your clothes and skin and get into the air you breathe when released from dryer vent emissions, which are not regulated by the Environmental Protection Agency. Because the fragrances manufacturers use are trade secrets, consumers have no way of knowing what they contain. Federal laws require only that cleaning products list the ingredients that are active disinfectants or known to pose hazards.

The International Fragrance Association has published a list of more than 3,100 fragrance compounds in known use. But neither the Food and Drug Administration nor the Consumer Product Safety Commission require that individual fragrance ingredients be listed on labels or Material Safety Data Sheets.

But a study, published in the August 2011 issue of the journal Air Quality, Atmosphere and Health, indicates that scented laundry items can actually contain numerous carcinogens and toxins not listed on the packaging, including acetaldehyde and benzene. The University of Washington researchers called the air vented from machines that used scented laundry detergent and scented dryer sheets toxic.

“This is an interesting source of pollution because emissions from dryer vents are essentially unregulated and unmonitored,” said lead author Anne Steinemann, a professor of civil and environmental engineering and of public affairs. “If they're coming out of a smokestack or tailpipe, they're regulated, but if they're coming out of a dryer vent, they're not.”

Steinemann notes that only one of the VOCs (volatile organic compounds) they identified, ethanol, was listed on the label of the products they tested.

The University of Washington study built upon a 2007 study that looked at the chemicals released by laundry products, air fresheners, cleaners, lotions and other scented consumer products. The second study focused on laundry vent emissions.

Researchers bought and pre-rinsed organic towels and gave them to two homeowners, who volunteered their washers and dryers for the study. Before starting, the machines were cleaned with vinegar and run for full cycles to eliminate as much previous residue as possible. They ran three cycles at each home, one without any cleaning or softening products; another with scented laundry detergent; and a third with scented dryer sheets. A canister in the dryer vents of the home captured the exhaust for analysis.

The researchers found more than 25 volatile organic compounds in the captured gases, including seven hazardous air pollutants such as acetaldehyde and benzene, which are classified by the Environmental Protection Agency as carcinogens and for which the agency has established no safe exposure level.

“These products can affect not only personal health, but also public and environmental health. The chemicals can go into the air, down the drain and into water bodies,” Steinemann said.

The project's website also includes letters from the public reporting health consequences from scented consumer products. Steinemann says the reports of adverse reactions to scented air coming from laundry vents is what motivated her to conduct this study.

It's probably best to ditch the dryer sheets altogether. But if you insist on using them, stick with the less toxic options. Seventh Generation makes dryer sheets out of chlorine-free recycled paper, instead of polyester, and they contain no fragrances or masking agents. The company also discloses all the ingredients of the sheets, which includes a plant-derived softening agent. 

Cliff Weathers is a former senior editor at AlterNet and served as a deputy editor at Consumer Reports. Twitter @cliffweathers.