Trump admin drops chemical program critics say was weaponized to target American manufacturing plants

The Environmental Protection Agency (EPA) is pivoting from a long-contested chemical risk assessment program it notes Congress never authorized and critics say became a tool for targeting chemical facilities, including plants sterilizing medical equipment at the height of COVID-19.

While the agency’s Integrated Risk Information System (IRIS) program was launched in 1985 as an internal library of chemical safety assessments, former agency insiders told The Lion that IRIS findings were never designed to stand alone. However, critics argue IRIS assessments have been wielded as a weapon by government agencies, lawyers and local communities – through litigation, regulation and public pressure campaigns – to target and even shut down chemical facilities.

EPA Deputy Administrator David Fotouhi issued an internal memo on April 27, writing that IRIS “values represent only the first two steps of the four-step risk assessment process and are not necessarily intended for use as regulatory levels. Before relying on IRIS values, users should ensure that the IRIS assessments and values are fit for their intended purpose and that the values are consistent with the most current scientific literature.”

Agency offices that used IRIS program information as part of regulatory decision-making should “review how that information was employed in their specific regulatory or programmatic actions and determine if any updates or changes are warranted,” Fotouhi wrote. He added that IRIS information would remain available, but with a disclaimer attached.

Green activist groups that have defended IRIS, such as Greenpeace, Earthjustice, the Environmental Defense Fund and the Natural Resources Defense Council, have also historically opposed the Trump administration’s broader deregulatory agenda, which has framed Biden-era and Obama-era environmental regulations as economically burdensome.

Notably, several top Biden EPA officials previously worked for some of these green groups, and the agency set aggressive regulations against the chemical industry during the Biden years.

Support for the shift away from IRIS has come from EPA stakeholders, the chemical industry and some energy policy experts. Chemical industry insiders told The Lion they do not view IRIS assessments as representing the best available science and that IRIS program values have been used by federal and state agencies to justify stringent regulations.

Previous efforts

The first Trump administration considered either improving IRIS assessments or eliminating the program altogether, according to Mandy Gunasekara, the EPA’s chief of staff at the time. Gunasekara told The Lion that during her time at the EPA she witnessed “pervasive consequences from the misuse of IRIS as an assessment tool.”

Gunasekara recalled efforts to shut down chemical facilities, noting that demonstrators donned an IRIS assessment number on t-shirts (0.2) that was “grossly taken out of context and flew in the face of general consensus around it. … Nonetheless, trial attorneys ginned up these community groups and fed them this misinformation,” Gunasekara said.

She noted that ethylene oxide (EtO) plants were targeted, even at the height of the COVID-19 pandemic. EtO is used to sterilize medical equipment, including medical devices that were vital during the pandemic, such as respirators.

“There were a lot of folks in the career offices that liked IRIS as a regulatory tool [or] something to take into consideration, but they were extremely frustrated with how one factor in a broader analysis was ultimately used to try and create this false sense of achieving zero risk,” Gunasekara said. She added that under IRIS assessments, the only way to completely eliminate EtO risks “meant shutting down these facilities.”

Fotouhi referenced EtO in the memo, noting that a March 2026 EPA proposal states the chemical is five times safer than the 2016 IRIS figure. In the case of a 2024 EtO rule, the Biden EPA relied on the 2016 IRIS-derived toxicity value. Notably, the agency proposed reconsidering the rule in March “in response to legal, scientific and policy concerns.”

Gunasekara pointed to one recently shuttered plant as an example of the broader federal and community pressure facing chemical facilities.

Forcing a plant to shut down 

One Denka chemical plant – home to a region in Louisiana that attracted protesters citing EPA chemical safety levels – indefinitely suspended production in May 2025.

Denka noted in its closure announcement that it did not anticipate the costs associated with limiting chloroprene emissions.

A 2010 IRIS assessment found that chloroprene was “likely to be carcinogenic to humans,” and the EPA later released a National Air Toxics Assessment (NATA) in December 2015 that found higher-than-expected levels of chloroprene in the region.

Mounting community concerns and federal probing then led Denka to enter into an agreement with Louisiana in January 2017 to lower chloroprene emissions by 85%.

Denka’s plant and several other chemical facilities are home to a region nicknamed “cancer alley,” though the evidence is sparse and contested, according to the Louisiana State University Health Sciences Center New Orleans.

Protesters and reports on the plant tend to highlight that minority communities allegedly are disproportionally impacted by these emissions.

The Biden Department of Justice (DOJ) also filed a civil action complaint on behalf of the EPA against the Denka plant in February 2023, citing the 2010 IRIS assessment and calling on the plant to lower emissions beyond the 85% reduction goal. Additionally, an EPA 2024 presidential transition brief states that though the 85% reduction goal was met, emissions still exceeded the threshold derived from the 2010 IRIS assessment.

The Trump DOJ dismissed the EPA’s suit in March 2025, arguing the Biden EPA had invoked emergency powers without alleging any regulatory violation and framed the case as advancing its “environmental justice” agenda. The administration said the dismissal was consistent with President Donald Trump’s day-one executive order demanding an end to “radical” diversity, equity and inclusion programs and preferencing.

Additionally, the Environmental Defense Fund – the green group that Biden EPA Administrator Michael Regan previously worked for – entered the legal fight on the EPA’s side against Denka. In a joint legal filing alongside other intervenors, the group argued Denka’s claim that it might have to shut down over an emissions reduction compliance deadline was “hard to take seriously” as its parent company is a “massive multinational conglomerate.”

Denka closed the plant 11 months later, citing unanticipated costs and staffing needed for the emissions equipment.

The plant was the only facility in the U.S. that produced neoprene, a rubber used to make some adhesives, wetsuits, orthopedic braces and medical gloves. The U.S. is a major importer of neoprene products and was the largest importer of neoprene latex in 2024, relying on Germany, Japan and China’s exports, according to data from the Global Trade Algorithmic Intelligence Center.

The cost of regulation

Another longtime critic of IRIS assessments is the Competitive Enterprise Institute, a conservative think tank.

CEI’s Director of the Center for Energy and Environment Daren Bakst told The Lion, “It is always important to remember that there can be a huge cost for not allowing something.”

“Chemicals are a critical part of our lives,” Bakst said. “They exist in nature and are used in many ways to help advance human prosperity and well-being. This includes improving our health and safety. If flawed and overly precautionary assessments are informing the EPA, then extremely important chemicals may not be made available.”

Despite its limitations, some EPA staffers want to keep using IRIS, according to former Trump EPA transition team member and Energy and Environment Legal Institute Senior Fellow Steve Milloy.

Milloy described IRIS as a “frozen in time database” that grants the agency “maximum flexibility to do what it wants with any given chemical.”

He added that though he believes the EPA relies on “50 years of bad regulation,” the Trump administration must clearly justify its deregulatory moves, or else “everything is going to look like they’re cherry picking and doing dastardly deeds for the chemical industry.”

EPA Spokeswoman Brigit Hirsch told The Lion the April 27 memo “unequivocally does not rescind, revise, or re-open any existing regulatory standard, level, or decision or direct outside entities to do so.”

“If a program office determines that a change is warranted in light of this review, it will follow all required steps to propose such a change,” she said. “As has always been the case, any revision to a regulatory standard must follow all applicable procedures, often including public participation.”

The EPA will expand the role of its program offices in conducting risk assessments tied to their regulatory responsibilities, building on work many of them already perform, Hirsch said. Certain offices are already tasked with administering laws such as the Clean Air Act or the Atomic Energy Act, as is the case with the Office of Air and Radiation.

Some reports have characterized the restructuring as potentially politicizing independent science, but Hirsch said that the changes will allow assessments to be faster and directly responsive to Congressional statutes. The EPA has added more scientists and technical staff to program offices as well, Hirsch said.

“The Trump EPA is committed to protecting Americans from toxic chemical exposure and is delivering that protection by relying on gold standard science, the most rigorous, transparent studies and information available,” Hirsch continued, arguing that IRIS assessments “did not always fully account for critical scientific considerations like mode-of-action information (which explains how a substance actually causes harm in the body) and were not always tailored to the specific regulatory decisions they were meant to inform.”

Welcoming change

Representatives of industry stakeholders, including for National Funeral Directors Association and the Society of Chemical Manufacturers & Affiliates, also told The Lion they responded favorably to the shift from IRIS.

The Government Accountability Office (GAO) has flagged IRIS for delayed reviews and has placed the program on a high-risk watchlist multiple times, though the most recent review noted there have been some improvements to program management.

The American Chemistry Council (ACC) frequently cites the GAO critiques and has been at the forefront of opposing the IRIS program. In addition to ACC, a coalition of 81 different industry groups signed onto a letter in January 2025, urging EPA to address their problems with IRIS.

ACC’s vice president of regulatory and scientific affairs, Dr. Kimberly Wise White, told The Lion that the group supports recently introduced legislation that would prohibit the EPA from using IRIS assessments for regulations or permitting.

The No Industrial Restrictions in Secret Act of 2025, known as the NO IRIS Act, was introduced in February 2025 by Rep. Glenn Grothman, R-Wisconsin, in the House and Sen. John Kennedy, R-Louisiana, in the Senate.

Grothman highlighted IRIS’ lack of Congressional authorization in a statement to The Lion, arguing that the program “has for years operated in a way that puts unrealistic burdens on American industry.”

Grothman added that “I’m encouraged to see the EPA taking steps to address these issues and moving toward a more transparent, accountable process grounded in sound science. … If we truly care about reducing emissions worldwide, it needs to be a priority to keep manufacturing in the United States in a manner that reflects Gold Standard Science.”

“In too many cases, IRIS assessments pushed impractical toxicity standards and emissions thresholds far below naturally occurring ambient levels. That’s a direct hit on small businesses who don’t have the resources to chase ever-changing or unattainable standards,” Grothman said. “When you set targets that are effectively impossible to meet, you don’t get better outcomes; you get stalled projects, fewer jobs, less innovation, and manufacturing outsourced to countries whose scientific standards are already more lax than the United States.”