The US Environmental Protection Agency on Tuesday proposed a set of new restrictions on facilities that use the cancer-causing chemical ethylene oxide, a colorless, odorless gas that is used to sterilize medical devices and spices.
The agency said the new rules, which have not been finalized, would help to reduce ethylene oxide gas that these facilities release by 80%, bringing emissions below a Clean Air Act standard for elevated cancer risk.
Communities exposed to ethylene oxide gas have been pushing the EPA to put tighter controls on plants that use ethylene oxide gas.
In 2018, an EPA report found that dozens of communities across the nation faced elevated cancer risks because of trace of amounts of ethylene oxide released into air as part of the sterilization process.
The EPA issued the report on the new risks without issuing a news release, as it had done for the same report in years past. Some affected communities learned of the risk through a health assessment conducted by the Agency for Toxic Substances and Disease Registry, a division of the US Centers for Disease Control and Prevention, and media reports. A report from the EPA’s Office of the Inspector General found that some communities weren’t alerted to their risk by EPA at all.
The elevated risk became apparent after a two-decade long review of the toxicity of ethylene oxide by scientists in EPA’s Integrated Risk Information System (IRIS) program.
While the EPA acknowledged that ethylene oxide was more dangerous that had been previously understood, it continued to use an older set of rules to regulate facilities that released ethylene oxide as well as companies that manufacture it.
The proposed rules aim to better align regulations on the producers and users of ethylene oxide with the cancer risk posed by the chemical. They follow a set of proposed rules issued by EPA last week that would put new controls on facilities that manufacture ethylene oxide.
Taken together, the two sets of rules would remove 77 tons of ethylene oxide emissions a year, an 84% reduction compared with 2020 levels, EPA Deputy Administrator Janet McCabe said in a call with reporters on Tuesday.
Environmental watchdog groups applauded the proposed restrictions, but noted that they don’t go far enough to protect vulnerable communities, where residents are often low-income and disproportionately people of color.
“These regulations are long overdue, by almost a decade. I’m relieved and pleased that the EPA has finally issued proposed standards that are based on their own scientists’ recommendations on an updated, higher cancer risk value. If enacted, these updated regulations would reduce emissions in fenceline communities,” said Darya Minovi, a senior researcher scientist at the Union of Concerned Scientists.
“When the EPA issues the final rule, they should throw the net wider. The standard should cover a larger range of facilities to include off-site warehouses that often store recently sterilized equipment that continue to release ethylene oxide, but aren’t regulated for their air emissions.”
Minovi also said the EPA should require fenceline monitors – devices that constantly read the air outside of facilities to make sure that toxic gas isn’t drifting into neighborhoods.
Jaime Rukstales, a member of the Illinois grassroots advocacy group Stop EtO in Lake County – one of the communities impacted by ethylene oxide pollution – says the EPA needs to impose tougher restrictions on “all types of facilities that impact the health of our communities … including sterilizers, manufacturers and warehouses near our homes, schools and businesses.”
Some off-site warehouses used to store newly sterilized products have registered high levels of ethylene oxide due to off-gassing of the products.
Meanwhile, chemical manufacturers sued the EPA in February over its updated hazard assessment for ethylene oxide. The industry wants the agency to use a less protective standard developed by the Texas Commission on Environmental Quality.
AdvaMed, a group that lobbies for the interests of medical device manufacturers, warned that more regulations could pose problems for patients.
“If new EPA regulations force sterilization facilities to close, patients could face treatment delays as sterile technology supplies, such as pacemakers and surgical equipment, fall short,” Scott Whitaker, president and CEO of AdvaMed, said in a comment posted on the group’s website.
The EPA said some commercial sterilizers have already made the planned changes.
“Many sterilization and health care facilities are already taking the steps outlined in the proposal and have seen emissions drop significantly,” McCabe said.
Most facilities have taken action to control ethylene oxide blown out of sterilization chambers through exhaust vents known as “back vents” but only 25% to 33% of sterilizers are controlling so-called fugitive emissions, ethylene oxide that escapes or leaks into room air, said Jonathan Witt, an environmental engineer and technical lead on EPA’s review of the National Emissions Standards for Hazardous Air Pollutants.
“So we think it’s a good sizable chunk of the industry, but still a little ways to go,” Witt said on a call with reporters.
If the rules go into effect, sterilizers would have 18 months to make the changes, which the EPA said is an accelerated time frame under the Clean Air Act.
AdvaMed’s Whitaker says that’s not enough time.
“It could take many months for abatement equipment to arrive. Supply chains and manufacturing are still recovering from the pandemic,” he noted in the statement.
In issuing the proposed rules, the EPA said it aimed to strike a balance between lowing cancer risks for impacted communities and workers who use ethylene oxide while preserving “critical sterilization capabilities.”
The proposed rules would apply to 86 commercial sterilization facilities in the United States that use ethylene oxide gas to fumigate spices and medical devices.
The EPA says 20 billion medical devices – mostly single-use, disposable items used in health care such as catheters, gloves and surgical gowns – are sterilized using ethylene oxide.
The US Food and Drug Administration is actively exploring alternatives to the use of the gas, the EPA said on Tuesday, but some devices still can’t be sterilized any other way.
In proposing the new rules, EPA said its new analysis found that exposure to ethylene oxide, or EtO, on the job significantly increased cancer risks for workers in sterilization facilities and those who apply ethylene oxide in health care facilities.
“Now, a new EPA analysis shows that there may also be significant risks to workers who handle [ethylene oxide] and people who live, work or go to school near places where EtO is used in sterilization. And failing to take action to address these risks is simply unacceptable,” EPA Administrator Janet McCabe said on a call with reporters.
The additional lifetime cancer risk for a worker exposed to ethylene oxide for eight hours a day, 240 days a year for 35 years was between 1 in 10 and 1 in 36 for workers in sterilization facilities; and between 1 in 12 and 1 in 25 for workers exposed to ethylene oxide in health care facilities.
To help lower those risks, the proposed rules require greater use of personal protective equipment for workers and new controls to decrease the amount of ethylene oxide in indoor air.
Whitaker from AdvaMed, the medical device industry group, said the cancer risk for employees exposed to ethylene oxide on the job is overstated and disregards “the strong employee protections already in practice.”
Companies will also be required to use new real-time monitoring methods to confirm that these pollution controls are working inside facilities. These controls can measure ethylene oxide in indoor air down to 10 parts per billion. If ethylene oxide levels climb above this threshold, everyone in the workplace would be required to wear protective equipment.
They will also lower the amount of ethylene oxide that can be used for each sterilization cycle. The EPA is proposing to limit the application rate for ethylene oxide to no more than 500 milligrams per liter of air.
The rules would eliminate some niche uses of ethylene oxide where alternatives exist, including its use in museums, archival settings, beekeeping, some cosmetics, and in musical instruments.
The EPA will take public comment on the new rules for 60 days. The agency will also host a virtual public webinar on May 1 to discuss its proposed rules and new risk assessment.