Examine a bottle of Palmolive dishwasher soap or Tide laundry detergent and try to figure out what chemicals they use to break down grease or produce suds. Stuck? You're not alone. Those chemicals aren't listed.

That concerns some consumers, public health advocates and scientists, who say some of these chemicals may be bad for human health and the environment. "I want a clean home but I'm worried about the toxic health impacts of the cleaners," says Barbara Weir of East Islip, N.Y., a consumer who spoke on a conference call organized by environmental advocates Earthjustice. "I think consumers have a right to know what they're buying."

This week, a group of those concerned citizens and advocates, led by Earthjustice, is filing a lawsuit in New York State to force major U.S. manufacturers—Church & Dwight, Colgate–Palmolive and Proctor & Gamble as well as England-based Reckitt Benckiser Group—to disclose ingredients in their household cleaning products. "Consumers deserve to know whether the products they use to wash their dishes, launder their clothes or clean their homes are harmful to themselves or their environment," says Keri Powell, an attorney at Earthjustice.

The lawsuit revolves around a law passed in 1971—but rarely enforced, says Earthjustice—that gives the New York State Department of Environmental Conservation (DEC) the power to force manufacturers to disclose the ingredients of their products as well as any health or safety studies. And, should the DEC commissioner feel it is warranted, it also allows the state to ban the use of certain chemicals—a power that was last invoked back in 1985 to ban the solvent nitroacetic acid, or NTA, that was shown to cause cancer in lab animals, according to program associate Saima Anjam of Environmental Advocates of New York.

Several companies—method, Prestige Brands, Seventh Generation, Sunshine Makers and Weiman Products—filed reports with the DEC to comply with the law when contacted by Earthjustice last September. Sunshine Makers, for example, detailed the ingredients of their "Simple Green" product line. Their All-Purpose Cleaner contains 2-butoxyethanol, a solvent which has been shown to reduce fertility in female lab mice and damaged human red blood cells at high levels in vitro.

But the companies named in the suit—whose plaintiffs also include the Sierra Club and the American Lung Association—either refused to submit such a report or did not respond at all. "We can't comment on pending litigation," Kate DiCarlo, a spokeswoman for Procter & Gamble, told ScientificAmerican.com.

The 1971 law made New York a trendsetter as there is no equivalent in other states or at the federal level, according to Ben Dunham, an associate legislative counsel at Earthjustice. "The federal system to regulate toxic chemicals is just in shambles," he says, noting that the Toxic Substances Control Act of 1976 failed to allow the U.S. Environmental Protection Agency (EPA) to regulate asbestos, despite proof that it is harmful. A law introduced in the House in 2008, known as the Kid-Safe Chemicals Act, would attempt to put the burden of proving a given chemical is safe on manufacturers rather than on the EPA to prove it is unsafe; it will likely be reintroduced this year in Congress.

The chemical industry has launched a voluntary effort to address these issues but "a voluntary program doesn't give you that confidence that the information is going to be accurate," says Tom Neltner, co-chair of the Sierra Club's Toxics Committee. Companies sell at least $14 billion worth of such cleaners, according to Euromonitor International.

An additional problem: Even if you know what's in your cleaner, you may not know whether it's safe or not. "One of the problems that none of this is addressing is that there are more than 100,000 chemicals in commerce and maybe 900 evaluations of chemicals for cancer-risk," says chemist Monona Rossol, industrial hygienist for Arts, Crafts and Theater Safety, a nonprofit that advises on chemical safety for theaters and artists. "For the majority of chemicals, there just isn't any data."

Some studies have shown that certain glycol ethers can irritate the lungs—exacerbating asthma—and, at higher exposure levels, damage red blood cells or reduce sperm count. Chlorine compounds in cleaning products have also been found to exacerbate asthma, whereas certain surfactants—such as nonylphenol ethoxylates—have been shown to grow breast cancer cells in the lab as well as interfere with the reproductive organs of aquatic species from frogs to fish. But, says physician Ted Schettler, science director for the Science & Environmental Health Network, an organization founded by environmental groups to assess health impacts: "We have no idea how those lab results translate to public health impacts."