WASHINGTON — The U.S. law on chemical safety is 37 years old, riddled with exceptions and widely considered ineffective — so much so that the government hasn't even tried to restrict an unsafe chemical since courts overturned its asbestos ban in 1991.

Now that law could soon get a face-lift, amid growing concern that ingredients in ordinary consumer products are leading to health problems.

On Wednesday, Sen. Frank Lautenberg, D-N.J., and Sen. David Vitter, R-La., announced that they had reached a "groundbreaking" agreement to revamp the Toxic Substances Control Act of 1976, ending two decades of gridlock in the Senate over how to test and regulate the tens of thousands of chemicals found in everything from crib mattresses to water bottles.

If the legislation were to pass, it would be the first time that a major U.S. environmental law was updated since the 1990 overhaul of the Clean Air Act.

"This bill proves that bipartisan compromise can still work in Washington," said Sen. Joe Manchin, D-W.Va., who Senate staffers say was critical in bringing together the main sponsors. All told, the bill has eight Democratic co-sponsors and eight Republicans onboard.

The American Chemistry Council, which represents manufacturers such as Dow and Dupont, hailed the compromise. Environmentalists were split, with some viewing it as a encouraging step and others saying it would do too little.

All sides seemed to agree that the current process is dysfunctional. Under the Toxic Substances Control Act, the Environmental Protection Agency (EPA) can call for testing of a chemical only if evidence surfaces that the substance is dangerous. What's more, tens of thousands of existing chemicals were exempt from review when the law was enacted in 1976.

The law also set a high bar for the EPA to regulate dangerous chemicals — it requires the agency to find the "least burdensome alternative" to current practice, a difficult standard to meet.

All told, the government has required testing for 200 of the 84,000 chemicals registered in the United States — and banned five substances deemed dangerous.

In recent years, however, worries about chemical safety have grown. Several states have moved to ban certain chemicals in everyday products, including Bisphenol A, a chemical widely used in plastics. And in recent years, the flame retardants used in household furniture have come under scrutiny for potential health risks.

Lautenberg has noted that the Centers for Disease Control and Prevention have found at least 212 industrial chemicals in humans, "including at least six known carcinogens and dozens that are linked to cancer, birth defects and other diseases."

To address those concerns, the Lautenberg-Vitter Chemical Safety Improvement Act of 2013 would give the EPA various new tools:

* The agency would review all actively used chemicals and label them as either high or low priority based on their potential risk to human health and the environment. The agency would then subject high-priority chemicals to further review.

* Regulators would no longer have to go through a long, protracted rule-making process to get information from companies about their chemicals.

* The EPA would have greater flexibility to take action on chemicals deemed unsafe, ranging from labeling requirements to outright bans on things such as asbestos.

When previous iterations of this bill were considered, the American Chemistry Council worried that the EPA approval process for new chemicals would be too cumbersome and would slow the pace of new products coming to market. In the compromise, the EPA would have to declare that new products are "likely to be safe."

"We think it's a very fair and very balanced proposal," said Calvin Dooley, president of the American Chemistry Council. He added that chemical companies were prepared to comply with the EPA's requests for more information "in a cost-effective way."

Environmentalists' reactions were more mixed. Ken Cook, president of the Environmental Working Group, said the compromise was a scaled-back version of previous bills from Lautenberg, including stricter health standards for assessing chemicals.

"This bill is basically the least that could be done," Cook said. He expressed concern that it could preempt stricter state laws and would allow chemical companies to have the government deem their products safe.

By contrast, Richard Denison of the Environmental Defense Fund said the bill is "certainly a net improvement over the status quo," although he worried that the lack of hard deadlines in the legislation could allow delays in the regulatory process if the measure passed.

Co-sponsors include Kirsten Gillibrand, D-N.Y.; Mike Crapo, R-Idaho; Richard Durbin, D-Ill.; Lamar Alexander, R-Tenn.; Charles Schumer, D-N.Y.; James Inhofe, R-Okla.; Tom Udall, D-N.M.; Susan Collins, R-Maine; Mary Landrieu, D-La.; Marco Rubio, R-Fla.; John Boozman, R-Ark.; Robert Menendez, D-N.J.; John Hoeven, R-N.D.; and Manchin.