On Wednesday, 15 health and environmental groups including Greenpeace, the Environmental Working Group and the Breast Cancer Fund will send legislators a letter asking them to oppose the measure.
"We respect and appreciate the efforts to identify areas of bipartisan compromise and consensus on chemical safety legislation," they write. The bill, however, "has serious limitations and will fall far short of our shared goal of safeguarding human health from the risks posed by exposure to toxic chemicals."
They are aided by 34 law professors and public interest lawyers, who warn in a separate letter to leaders on the Senate Environment and Public Works Committee and the House Energy and Commerce Committee that the bill could limit the EPA from issuing new rules.
The lawyers claim that the legislation requires the EPA to justify new safety tests and makes it difficult to prove that they are dangerous, while offering protections for chemical companies.
Those assessments are in opposition to the trade associations in the American Alliance for Innovation coalition, which endorsed the measure on Tuesday.
In a statement, the nearly 90 organizations in the coalition, including U.S. Chamber of Commerce, the National Retail Federation and the National Association of Manufacturers, said the bill "provides a solid scientific foundation for regulatory decisions and provides clear direction for EPA to create a transparent, efficient and sensible process to manage the safety of chemicals in commerce."
Former EPA officials in charge of toxic chemicals have endorsed the measure in recent weeks, as have the Environmental Defense Fund and the Humane Society.
On Thursday, the House Energy and Commerce Committee will hold a hearing on the Toxic Substances Control Act with representatives from environmental, health and chemical groups.