"The scented fabric sheet makes your shirts and socks  smell flowery fresh and clean. That plug-in air freshener fills your home with  inviting fragrances of apple and cinnamon or a country garden. But those common  household items are potentially exposing your family and friends to dangerous  chemicals, a University of Washington study has found. 
 Trouble is, you have no way of knowing it. Manufacturers  of detergents, laundry sheets and air fresheners aren't required to list all of  their ingredients on their labels -- or anywhere else. Laws protecting people  from indoor air pollution from consumer products are limited. When UW  engineering professor Anne Steinemann analyzed of some of these popular items,  she found 100 different volatile organic compounds measuring 300 parts per  billion or more -- some of which can be cancerous or cause harm to respiratory,  reproductive, neurological and other organ systems. Some of  the chemicals are categorized as hazardous or toxic by federal regulatory  agencies. But the labels tell a different story, naming only innocuous-sounding  'perfume' or 'biodegradable' contents."