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US EPA aims to crack down on chemical makers’ ethylene oxide emissions

Proposed regulation would require facilities to control leaks

by Cheryl Hogue
November 7, 2019


Drawing shows chemical structure of ethylene oxide.
Credit: Shutterstock

US chemical manufacturers would have to trim their annual emissions of ethylene oxide, a carcinogenic gas, under an Environmental Protection Agency proposal.

Ethylene oxide emissions from chemical manufacturing plants would fall by about 9 metric tons (t) per year under the proposed regulation, the EPA says. The agency wants to require facilities to control emissions of the gas from storage tanks, vents, and leaky equipment.

Chemical plants collectively reported emitting about 100 t of ethylene oxide in 2018, according to the EPA Toxics Release Inventory. Of this, about 42 t were fugitive emissions that leak from vents, pumps, and valves, the inventory data show.

Ethylene oxide, which is made from petroleum or natural gas, is a chemical building block for making plastics, detergents, medicines, solvents, and a slew of other products. The substance is also used to sterilize medical devices.

The proposed rule, which the EPA unveiled Nov. 6, is aimed at trimming about 105 t of hazardous air pollutants, including toluene and methanol in addition to ethylene oxide, from manufacturers of miscellaneous organic chemicals. The agency says this sector’s current releases of toxic pollutants pose unacceptable risks of cancer to the public.

The EPA is under a federal court order to finalize the regulation by March 13, 2020.

“EPA’s actions underscore the Trump Administration’s commitment to addressing and reducing hazardous air pollutants, including ethylene oxide emissions, across the country,” says EPA administrator Andrew Wheeler.

The Ethylene Oxide Panel of the American Chemistry Council, a trade association of chemical manufacturers, says it is reviewing the proposal. Companies that make and use this chemical are investing in research and product stewardship technologies to protect the health of communities around their plants, the panel says in a statement.

In a related move, the EPA says it is studying the amount of airborne ethylene oxide in urban and rural areas that aren’t near industrial facilities that make or use the chemical.



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