Trying to make scents of the chemicals in household cleaners

Labels of the all-purpose cleaners we've just tested typically warn you to protect your eyes, skin and clothing during use. Much less common is a warning to ventilate your surroundings—although most of the products might include synthetic fragrances that, according to critics, contain ingredients that can cause breathing problems, affect hormone levels, and raise the risk of cancer.

The key word is "might," for manufacturers of products containing fragrances aren't required by federal law to list every chemical compound on the labels. To do so would be difficult if not impossible, since one fragrance can contain 50 to 100 different compounds. Companies also call much of this information "confidential business information"—trade secrets that they shield from the competition.
 
But efforts are under way to require makers of household products such as cleaners to do more than they're doing now. One U.S. Senate bill, dubbed the Safe Chemicals Act of 2010, would update the Toxic Substances Control Act of 1976 to require manufacturers to prove to the Environmental Protection Agency the safety of every chemical in a household product on the market. And in New York State, the Department of Environmental Conservation is considering how to enforce a law, on the books since 1971, that requires manufacturers to share even confidential data on compounds in their products with the state, which in turn would issue public warnings when appropriate.
 

The large companies involved are quick to say they are already revealing ingredients of their products. Clorox Co., Procter & Gamble, Reckitt Benckiser, and S.C. Johnson are among manufacturers that list ingredients by product on their websites. Still a growing body of research says the seemingly innocuous "fragrance," can be a hidden hazard by itself.
 
One recent study (PDF), from the University of Washington, measured the levels of volatile organic compounds (VOCs) in 25 common fragranced consumer products, including household cleaners. (VOCs are linked to ozone, smog, respiratory illnesses, indoor air pollution and memory impairment.) Of the 133 unique VOCs the study identified, 24 are classified as toxic or hazardous under at least one federal law. Four of the 24, including formaldehyde, are compounds the EPA has classified as probable carcinogens.
 
Several of the 24 VOCs fall under the chemical class of terpenes. Of these, limonene is commonly found in household cleaners; others include camphor and alpha-pinene. Terpenes in particular can react with ozone—whether ambient or emitted by an air purifier—to create formaldehyde and other irritants. The same combination can create ultrafine particles that hang in the air before settling and can be easily inhaled.
 
Industry organizations such as the Consumer Specialty Products Association (CSPA) and the International Fragrance Association (IFRA) call claims in the University of Washington study misleading and its criticisms overly broad. The IFRA in particular noted that a number of the VOCs the study cites are present in many natural foods, including fruit, in concentrations similar to or higher than the parts-per-million levels present in the tested household products. The CSPA's take: "These products are safe when used according to product labels, and they have been utilized safely by consumers for decades."
 
Consumers Union, which publishes Consumer Reports, believes that consumers have a right to know what's in their products. CU supports government efforts to advise consumers of any and all risks in using a product, even if the label doesn't allow a complete listing of product ingredients. While the debate continues, our advice is to play it safe when you use a household cleaner, even one billed as "green." Start with the label's warnings. And whether or not you read a caution to ventilate, crack open a window.
 
—Ed Perratore
 
All-purpose cleaner Ratings: The results of our tests will be available online and on newsstands in early December.