Exactly what's in floor cleaner? What's stain remover made of? And what effects, if any, might they have on human health or the environment?

Environmental advocates want to know, and they asked a court Thursday to use a 1971 New York state law to force such manufacturers as Procter & Gamble and Colgate-Palmolive to reveal just what makes up such household staples as Ajax, Ivory soap and Tide.

The cleanser industry - which recently ramped up voluntary efforts to unveil product ingredients - says that the legal case is unwarranted, and that fears about health risks are misinformed.

But groups including the American Lung Association and the Sierra Club want the public to know more.

Members "want access to the information so they can determine the kind of chemicals that they are introducing into their homes and whether there are any risks associated with them," Keri Powell, an attorney for the environmental firm Earthjustice, told a state judge at a hearing Thursday.

A victory in the New York case would require companies to report their contents only to the state. But the advocates hope it will fuel nationwide reform of regulations on chemicals in cleaners and other products.

The case comes amid growing concerns about potential toxins lurking in consumer goods, from the heavy metal cadmium in jewelry to the chemical bisphenol A in baby bottles. While lawyers argued the cleaning-products case in New York, a Senate subcommittee in Washington held a hearing to examine current science on the public's exposure to toxic chemicals.

Some studies have linked cleaning product components to asthma, antibiotic resistance, hormone changes and other health problems. The industry's major trade group, the Soap and Detergent Association, assails the research as flawed, says the products are safe if used correctly and notes that cleaning can itself help stop the spread of disease.

Federal environmental laws don't require most household cleaning products to list their ingredients, though there are congressional proposals to change that. The Consumer Product Safety Commission requires hazard warning labels on some cleansers, and the National Institutes of Health offer some health and safety information for hundreds of cleaning products, drawn from data gathered for industrial use.

Cleanser industry groups unveiled their own ingredient-listing initiative last month, offering information on participating manufacturers' Web sites. New York-based Colgate-Palmolive Co., Cincinnati-based Procter & Gamble Co. and several other industry heavyweights are participating.

"We think we've done it in a meaningful way that provides more information than ever before," Soap and Detergent Association spokesman Brian Sansoni said.

Environmental advocates welcome the disclosures but say they are too selective and vague - some components can be listed simply as "fragrance" or "dye," for instance.

"We must be careful about exposures for all household chemicals," said Joseph A. Gardella Jr., a Sierra Club member from Buffalo.

The activists say only regulation can insure full disclosure, and they hope the New York law can serve as a model.

The law and subsequent regulations authorized the state Department of Environmental Conservation to make manufacturers detail household cleaning products' ingredients, as well as any company-led research on the products' health and environmental effects.

The DEC, and the companies fighting the lawsuit, say the law allows but doesn't require the agency to collect the data. The companies have said in legal papers they would make the disclosures if required but haven't been officially asked.

"The DEC has never enforced these regulations," John J. Kuster, a lawyer for New York-based Colgate-Palmolive, told the judge Thursday.

The companies - also including Church & Dwight Co. Inc., Procter & Gamble and Reckitt-Benckiser Inc. - asked a state Supreme Court judge to dismiss the case. There's no definite time frame for a ruling.

Reckitt-Benckiser, a British company with its U.S. headquarters in Parsippany, N.J., makes products including Lysol and Woolite. Princeton, N.J.-based Church & Dwight makes Arm & Hammer cleaners, among other items.

Some other companies have sent ingredient lists to the DEC since Earthjustice and other organizations began asking in 2008.

Seventh Generation, which prides itself on its environmental bona fides, already listed ingredients on most of its cleaning products' packages. But the Burlington, Vt.-based company said it released more detailed information to the New York environmental agency, including the percentage of various ingredients within cleaners.

"We thought it was the right thing to do," said Dave Rapaport, Seventh Generation's Senior Director of Corporate Consciousness.

The DEC is looking at ways to publicize such information for consumers who want it, spokeswoman Maureen Wren said.