The scariest part about the 2014 chemical spill in West Virginia was that, in the beginning, no one really knew anything about the chemical that poisoned their drinking water. Ten thousand gallons of a licorice-scented chemical called MCHM had leaked from a storage container into the Elk River, a tap water source for 300,000 people in Charleston. Schools closed, hospitals evacuated patients, and the local economy of the state’s most populated city came grinding to a halt. For weeks, citizens were unsure whether they had been exposed to unsafe levels of the chemical, and what exactly MCHM would do to their bodies if they consumed it.

West Virginians did eventually get a clearer picture of MCHM. Tom Burke, who served as the Environmental Protection Agency’s chief science adviser under President Obama, thinks that’s partially because of an EPA program called the Integrated Risk Information System (IRIS), which assesses the health risks of thousands of chemicals across the country. “When there is a mystery like West Virginia, it’s those world-class scientists in the IRIS program that do the exposure assessment and risk analysis that lead to future decision-making about the chemical,” he told me. Congress is well aware of its value. “From the dusts of the World Trade Center and the faucets of Flint; to the toxic waters of Katrina and Harvey; [IRIS scientists] are there, working selflessly to protect our nation’s environment and public health,” Burke said in September before a House Science Committee hearing on the program. “Our health depends on them.”

We may not be able to depend on them for much longer. On Monday, the Republican-controlled Senate released a spending bill that eliminates IRIS. The bill asserts that IRIS’s functions would be maintained, just transferred to the agency’s Toxic Substances Control Act (TSCA) program. But Burke and others say the TSCA program is not large or well-funded enough to handle all the different types of chemical risk assessments IRIS does. “EPA’s ability to conduct risk evaluations under the new TSCA would be severely curtailed by the loss of both expertise and capacity that reside in the IRIS program,” wrote Richard Denison, a senior scientist at the Environmental Defense Fund.

But this is good news for companies that produce and disseminate chemicals. IRIS scientists’ findings have huge financial implications for polluters. When chemicals get into the air, soil, or water, regulators often base their cleanup requirements on what IRIS scientists say is safe. And chemical industry–funded scientists have been recently accusing the program of misconduct, claiming IRIS scientists exaggerate the health risks of certain chemicals. (One asserted that formaldehyde is not carcinogenic when inhaled.) A recent report also found that the IRIS program was operating more efficiently and more transparently than ever. That will surely cease being the case if the program is transferred to TSCA.

The Senate’s spending bill is just the latest victory for the chemical industry, which since Donald Trump’s inauguration has had a lot to celebrate. Freed from the Obama administration’s clampdown on safety, companies that produce essential but oftentimes toxic substances are seeing their stocks rally. Pesticides and chemicals banned for their poisonous nature are being newly reviewed; safety regulations are being relaxed; and industry representatives are being chosen for top government positions.