WASHINGTON — The Senate has passed a much-anticipated bill to revise the federal chemical safety law, which environmentalists have long argued puts the American public at unnecessary risk of exposure to toxic substances.
The bill has been in negotiations for more than two years. It finally went to a vote in the Senate on Thursday night and passed with bipartisan support. The bill now heads to a conference committee to be reconciled with a similar measure passed by the House.
The Senate version calls for a major overhaul of the 1976 Toxic Substances Control Act, which gives the Environmental Protection Agency authority to regulate chemicals. In recent years, environmentalists have sought major changes to the law, which they have argued does not give the EPA enough power when it comes to restricting toxic substances.
‘‘This law is about 40 years old, and it simply hasn’t kept up with the new science that is showing how chemicals can affect our health,’’ said Richard Denison, lead senior scientist with the Environmental Defense Fund.
A major problem with the existing law, according to Denison, is that it requires the EPA to demonstrate such a high burden of proof that a chemical is dangerous to human health as to make it nearly impossible to restrict a substance’s use.
The ‘‘poster child’’ for this issue is the EPA’s failed attempts to ban asbestos — a substance known for its cancer-causing qualities — in the 1980s.
As a result of restrictions in the current law, Denison said, the EPA has not been able to generate adequate information on many chemicals still commonly used in the United States, and there are also many restrictions on the information it’s permitted to share with the public, so as not to divulge confidential trade information.
‘‘Most people assume that the chemicals in the products and materials they encounter every day have been thoroughly tested and shown to be safe,’’ Denison said. ‘‘In fact, only a handful of chemicals have ever been reviewed for safety.’’
The new bill would grant greater authority to the EPA to study the effects of chemicals and regulate their use and has received wide support from both Democrats and Republicans. The bipartisan support is a reflection of the amount of time senators have spent negotiating the bill, a process that has required ‘‘careful balancing of the interests on both sides in this debate,’’ Denison said.
While the bill grants much greater regulatory authority to the EPA, which supporters hope will lead to more uniform, national health-based standards, it also includes some protections for the industry from state regulations.
The bill has also received support from members of the chemical industry.
The president of the National Association of Chemical Distributors, Eric Byer, said, ‘‘Today’s vote puts us on the doorstep of finally reforming an outdated law in a way that will build confidence in the US chemical regulatory system, protect human health and the environment from significant risks, and meet the commercial and competitive interests of the US chemical industry and the national economy.’’
The House of Representatives passed a similar, although much more limited, bill earlier in 2015 proposing some smaller-scale reforms to the toxic-chemicals law.
Negotiations between the House and the Senate could be complete, and a compromise bill sent to both chambers for a final vote by early 2016.