— A bill that he’s pushing to regulate toxic chemicals represents “the only realistic shot we have at reforming a very broken and dysfunctional system,” U.S. Sen. David Vitter, R-La., told a Senate committee Wednesday.

But Sen. Barbara Boxer, D-Calif., said, “Let’s be clear what we’re dealing with here: We’re dealing with a bill that does harm.”

Supporters of the bipartisan effort lead by Vitter and Sen. Tom Udall, D-N.M., to update the 1976 Toxic Substances Control Act said that public protection would be enhanced were the measure to be strengthened. They said the proposal represents a significant and long-overdue overhaul of the 1976 law.

Much of the testimony in the hearing revolved around what is doable, in comparison to what might be desirable, in terms of regulating chemicals.

“Major environmental laws do not get passed without bipartisan support,” Environment and Public Works Committee Chairman James Inhofe, R-Okla., said. He is a co-sponsor of the Udall-Vitter bill, as are 15 additional senators. The seven Democrats who have signed on to the legislation are enough to provide a filibuster-proof majority in the Senate, if the bill draws unanimous Republican support.

TSCA was intended to provide for the federal Environmental Protection Agency to protect Americans from exposure to toxic or harmful substances in clothing, furniture, cleaning products and elsewhere in the environment. But chemical manufacturers and environmentalists agree the law is outdated and largely ineffective. It largely exempted chemicals already in the marketplace from regulation, and a court decision that struck down a ban on asbestos weakened the law. Of the more than 80,000 chemicals in commercial use today, nine are regulated under TSCA.

Several states have stepped into the breach to regulate chemicals, and the status of future state enforcement efforts is a key point of contention in the TSCA debate. In Louisiana, home to the second-largest chemical manufacturing industry in the nation (after Texas), state laws regulate the presence of mercury and lead in consumer products.

The Udall-Vitter legislation would subject many more chemicals to regulation, set minimum requirements and timelines for EPA testing, establish a fee system to finance the program and address major weaknesses in TSCA revealed by the court decision in the asbestos case.

But it also would largely preempt additional state regulation of a chemical once EPA placed it on its high-priority list — and the EPA would have up to seven years to complete testing of the chemical. The chemical industry would prefer to avoid the complication of complying with a welter of different state regulations, although state laws on the books as of Jan. 1, 2015 would remain in effect.

“Are we here to accomplish something that protects the public health and environment while ensuring that American industry has the ability to continue to lead and innovate, or are we willing to let the status quo remain?” Vitter, a committee member, asked in the hearing room. Among the audience was Erin Brockovich, the environmental activist portrayed by Julia Roberts in the 2000 Hollywood movie of the same name.

Udall, who is not on the committee but showed up to speak for the bill, said, “I’m here because in my heart I believe this bill will do the job. I believe we have the opportunity to reform the law and save lives.”

Udall also said, “Sen. Vitter and I are not accustomed to working together on environmental issues.” Vitter is considered a friend of industry, while Udall has enjoyed a reputation as an environmentalist — although recent media reports have pointedly noted a surge in financial support for him from the chemical industry since he replaced Frank Lautenberg, the former New Jersey senator who died in 2013, as Vitter’s Democratic partner in the TSCA reform effort.

Members of the Democratic minority on the committee questioned Republican support for an expanded EPA enforcement role, in light of Republican efforts to cut funding for the agency. The committee took no action Wednesday on the bill, which is expected to win its approval when a vote occurs.

Several environmental groups oppose the legislation and prefer a Boxer bill that does not pre-empt state enforcement. That bill has attracted two cosponsors, neither one a Republican.

But the Environmental Defense Fund, which has a nearly 50-year history in the movement, backs the Udall-Vitter measure, as a pragmatic approach to TSCA.

“The need to reform this law is urgent,” EDF senior scientist Richard Denison told the committee.

“None of the provisions in the bill are perfect from our perspective,” he added. “Clearly, most of them represent compromises.”

Lautenberg’s widow, Bonnie, also testified for the bill.

“This cause is urgent, because we are living in a toxic world,” she said.

Opponents of the measure, she said, “are letting the perfect be the enemy of the good.”

Gregory Roberts is chief of The Advocate Washington bureau. His email address is groberts @theadvocate.com and he is on Twitter, @GregRobertsDC. For more coverage of national government and politics, follow The Advocate Politics Blog at http://blogs.the advocate.com/politicsblog.