The Environmental Protection Agency said on Friday that it would eliminate its scientific research arm and begin firing hundreds of chemists, biologists, toxicologists and other scientists, after denying for months that it intended to do so.
The move underscores how the Trump administration is forging ahead with efforts to slash the federal work force and dismantle federal agencies after the Supreme Court allowed these plans to proceed while legal challenges unfold. Government scientists have been particular targets of the administration’s large-scale layoffs.
The decision to dismantle the E.P.A.’s Office of Research and Development had been widely expected since March, when a leaked document that called for eliminating the office was first reported by The New York Times. But until Friday, the Trump administration maintained that no final decisions had been made.
The E.P.A.’s science office provides the independent research that underpins nearly all of the agency’s policies and regulations. It has analyzed the risks of hazardous chemicals, the impact of wildfire smoke on public health and the contamination of drinking water by hydraulic fracturing, or fracking. Its research has often justified stricter environmental rules, prompting pushback from chemical manufacturers and other industries.
Lee Zeldin, the E.P.A. administrator, has boasted about cutting dozens of environmental regulations, saying he wants to make it cheaper and easier for industries to operate.
When President Trump took office, the science office had roughly 1,155 employees. But more than 325 workers have left since January after accepting “deferred resignation” offers, according to an E.P.A. spokeswoman, Molly Vaseliou.
It was not immediately clear how many of the roughly 830 remaining employees would be fired. Ms. Vaseliou said in an email that the agency had not yet initiated the large-scale layoff, known as a “reduction in force.”
The American Federation of Government Employees Council 238, a union that represents more than 8,000 E.P.A. workers, slammed Friday’s announcement.
The science office “is the heart and brain of the E.P.A.,” said Justin Chen, president of A.F.G.E. Council 238. “Without it, we don’t have the means to assess impacts upon human health and the environment. Its destruction will devastate public health in our country.”
In a wave of departures in recent weeks, the directors of national research programs under the Office of Research and Development all left the E.P.A. They include career employees who oversaw work on measuring contaminants in the atmosphere, responses to environmental emergencies and exposure to chemicals and particulate matter. Others who left include the deputies of those programs, as well as dozens of senior scientists, according to multiple agency officials.
“It is dismantling a world-class organization, and the American people are not going to be well served by this,” Jennifer Orme-Zavaleta, who worked at the E.P.A. for 40 years and led the research office under the first Trump administration. “These actions are very shortsighted, and the way they’re going about it is very callous and very cruel.”
Since Mr. Trump took office, the E.P.A. has lost more than 3,700 employees through firings, retirements, resignations and other moves, dropping from 16,155 employees in January to 12,448 this month. That brings the agency’s work force to levels last seen during the Reagan administration.
The Trump administration previously announced that it would move some of the science functions into a new department in the E.P.A. administrator’s office. Ms. Orme-Zavaleta and others said that move threatened to politicize scientific research.
Chris Jahn, president of the American Chemistry Council, a lobbying group for the chemical industry, said in a statement that the organization “supports E.P.A. evaluating its resources to ensure American taxpayer dollars are being used efficiently and effectively.”
The Heritage Foundation, a conservative research organization, had criticized the E.P.A.’s science office in Project 2025, a blueprint for overhauling the federal government. The group had accused the office of being “bloated, unaccountable, closed, outcome-driven, hostile to public and legislative input, and inclined to pursue political rather than purely scientific goals.”
The Competitive Enterprise Institute, another conservative research organization, has called for eliminating or overhauling the office’s program for evaluating toxic chemicals, known as the Integrated Risk Information System, or IRIS.
“IRIS evaluations often rely on worst-case hazard assumptions that fail to consider real-world exposure scenarios,” James Broughel, a former senior fellow at the Competitive Enterprise Institute, wrote in a recent blog post. Mr. Broughel is now associated with the America First Policy Institute, a conservative think tank closely aligned with the Trump administration.
The E.P.A. said in a news release on Friday that it had already saved $748.8 million through “organizational improvements” and staff reductions. Mr. Zeldin said in the news release that agency officials were committed to “being responsible stewards of your hard-earned tax dollars.”
The E.P.A. plans to hold a “town hall” for staff members in the science office on Monday afternoon, according to a Friday evening email from Maureen Gwinn, the acting head of the office, a copy of which was reviewed by The New York Times.
“I understand that this announcement may bring uncertainty and concern,” Dr. Gwinn wrote. “While I don’t have all the details yet, I am actively working to gather more information.”
She concluded the email with a reminder: “Please remember to take care of yourselves.”