The Environmental Protection Agency (EPA) under President Donald Trump is facing a potential setback in its ability to update air pollution rules based on new scientific findings. This is particularly concerning for ethylene oxide, a chemical once considered unremarkable but now known to be 30 times more carcinogenic than previously thought. The EPA has been revising regulations to protect millions of people exposed to this compound, but its authority to do so is now under scrutiny.
The controversy arises from a legal interpretation by the Trump EPA, which suggests that the agency may not have the authority to reevaluate hazardous air pollution rules based on newly discovered harms if they have already been revised once. This interpretation could significantly limit the EPA's ability to address nearly 200 pollutants from thousands of industrial plants. Environmentalists argue that this decision could hinder the agency's response to new scientific evidence, potentially leading to unacceptable health risks.
The EPA's reconsideration of air pollution rules is centered around the Clean Air Act, which regulates hazardous air pollutants for various industrial operations. The agency must conduct assessments to determine if updates are necessary, considering emissions, chemical toxicity, and their impact on local residents. If risks exceed legal limits, the EPA must tighten rules.
The issue gained prominence in 2021 when the EPA's Office of Inspector General highlighted the toxicity of ethylene oxide, estimating that nearly half a million Americans faced unacceptable cancer risks. The EPA responded by conducting additional reviews and revising rules, asserting its authority under the Clean Air Act. However, the chemical industry challenged these actions, arguing that the EPA lacked the authority to conduct multiple risk reviews.
The Trump EPA's reconsideration of the ethylene oxide rules has led to exemptions for dozens of chemical plants and sterilizer facilities, allowing them to avoid stricter emissions standards. This process is expected to result in watered-down standards, raising concerns about the EPA's ability to effectively regulate hazardous air pollutants.
Despite these challenges, the EPA may still have alternative avenues to strengthen air pollution rules. Abel Russ, a senior attorney, suggests that the agency could use a separate section of the Clean Air Act to update rules if better pollution-control technology is affordable and available. However, limiting the EPA's ability to conduct residual risk reviews would significantly impact its authority over toxic pollutants.
Environmental groups are prepared to sue if the EPA concludes it lacks the legal authority to revise hazardous air pollution rules. They argue that the industry's comments are absurd and fail to account for the evolving nature of scientific knowledge about industrial pollution. Recent evidence of excessive pollution leakage from industrial facilities further underscores the need for ongoing risk assessments and regulatory updates.
