The fate of the medical device industry’s most widely used sterilization process lies in the hands of the Environmental Protection Agency, which gave the medtech industry mixed signals in November about the gas used to sterilize billions of devices annually.
The agency said it might seek to cut industrial emissions of ethylene oxide (EtO) by 93% nationwide. While that proposal doesn’t affect medtech directly, it may not bode well for an industry that relies on the gas that the EPA considers a carcinogen to sterilize about half of the devices it produces every year.
The February shutdown of a major Sterigenics EtO plant in Willowbrook, Ill. prompted the first in a series of FDA warnings about possible device shortages. Two other shutdowns followed in Georgia (one has since reopened), but state and local scrutiny of EtO emissions and public outcry may lead to what one industry advocate called a “rolling effect” of plant shutdowns and device shortages nationwide.
EtO sterilization works at low temperatures — between 90°F and 135°F — making it a viable option for devices made of multiple components and materials, including plastics, polymers, metals and glass, as well as coatings, bonds and packaging from damage. It can also penetrate different types of device packaging, enabling sterilizers to process truckloads’ worth of devices simultaneously.
The EPA is due to come out with proposed rules regarding commercial EtO operations in May 2020. Meanwhile, the FDA is seeking public input on alternatives to EtO and on methods to reduce emissions. The agency has been mum about responses to its pleas, issued in July. Medtech advocates argue that even if a viable alternative surfaces, it would take years and significant investments to institute, including the time to validate the new method for each device it would sterilize.
Some medtech manufacturers such as Becton Dickinson (BD), and Medline Industries sterilize their devices in-house, but many smaller firms rely on contract sterilizers such as Sterigenics. A Medline EtO plant in Waukegan, Ill. has also drawn attention, but an effort to make the company install a taller emissions stack failed.
The EPA sent medtech a potentially more positive signal in early November about how it measures EtO levels in the environment. The agency said it is working on updating how it characterizes air concentrations of the gas while it reviews the national emissions standards for EtO commercial sterilization operations.
Medtech industry trade group AdvaMed praised the EPA for reconsidering how it characterizes air concentrations of EtO. Specifically, the agency said it has begun to “examine the question of whether ethylene oxide is present more broadly in the air in the U.S., and if so, at what levels” — a step AdvaMed has been advocating for months.
The EPA has begun to analyze air quality samples from a subset of existing, longstanding monitoring stations that are not focused on specific industrial sources of EtO to determine whether the gas was present in the air. The most recent results confirmed the presence of ethylene oxide, with six-month averages ranging from about 0.2 to about 0.4 micrograms per cubic meter.
“We believe that there is no immediate, short-term risk from the levels of ethylene oxide found in these limited air monitoring data,” the agency said. “There is a need to better understand low levels of ethylene oxide over a longer-term period. EPA will continue to collect information from its existing air monitoring networks and share data as it becomes available.”
The agency also added EtO to the list of air toxins to be routinely monitored at all 34 monitoring sites, which are located in urban and rural areas.
“As part of EPA’s ongoing effort to protect people and the environment, yesterday’s preliminary test results show that EtO is present and safe at background levels,” AdvaMed said at the time. “Those levels are safe whether a sterilization facility is present or not. That’s an important finding, and we appreciate EPA’s commitment to doing further research here.
“EPA’s data shows that ambient air levels of EtO are far higher than the proposed standard that some have used as justification to shutter sterilization facilities,” the trade group added. “This demonstrates that the standard is not a reliable or useful gauge for determining appropriate emission levels of EtO. As we continue to study EtO’s presence in our atmosphere, it’s important to remember that leading toxicologists and epidemiologists confirm that the communities surrounding these facilities are safe. We look forward to working with EPA, FDA and other stakeholders to find a reasonable solution to the issue of EtO use that will allow for the continued safe and responsible sterilization of needed medical devices.”
The EPA is accepting comments on its proposal and will hold public hearings in early December in Washington, D.C. and Houston, Texas.
The agency said it will seek input on several topics, including possible approaches to calculate and control fugitive EtO emissions; potential improvements to EtO monitoring technologies; and process differences between types of sterilization facilities. The EPA will also seek information from several commercial sterilization companies on facility characteristics, control devices, work practices and costs for emission reductions.