Sterigenics said today that it has applied for permits to upgrade emissions controls at its Willowbrook, Ill. medical device sterilization plant, which had sterilized thousands of devices daily until its Feb.15 shutdown.

The Illinois Environmental Protection Agency (EPA) closed the Willowbrook plant, citing excessive emissions of the sterilant ethylene oxide (EO), based on a federal disease registry’s conclusion that residents and off-site workers in the area around the plant were at risk for a “30-fold increase in cancer potency.”

The shutdown created some device shortages and affected medtech giants such as Becton Dickinson (NYSE:BDX), Boston Scientific (NYSE:BSX), Medtronic (NYSE:MDT), Smith & Nephew (NYSE:SNN) and Stryker (NYSE:SYK), as well as medium-sized and smaller firms such as Teleflex (NYSE:TFX), Arthrex and ArthroCare, which also had devices processed there. The Willowbrook plant sterilized 594 types of devices, including sutures, clamps, knives, stents and needles.

Sterigenics is not the only company with Illinois operations seeking to upgrade its EO emissions controls in the wake of a tough new state law regulating discharge of the gas. The law could prevent the Willowbrook plant from reopening and bar other medtech sterilizers from opening new plants in the state, according to a report in the Cook County  (Ill.) Record.

Medline Industries said it has completed the first step of an emissions controls upgrade at its plant in Waukegan. “We remain confident that the additional emission control systems we have begun to install will substantially reduce our facility’s emissions,” the company said in an email to Medical Design & Outsourcing. Further emissions testing will be conducted later this summer and annually thereafter, Medline told us.

Sterigenics said the pollution control measures it wants to add at Willowbrook are consistent with upgrades that the company proposed to the Illinois EPA over the past several months and prior to the agency’s seal order. The upgrades would also allow the facility to comply with the new Illinois law regulating EO emissions and “would establish the Willowbrook facility as the highest emissions control environment” for EO sterilization facilities in the country, Sterigenics said.

The new equipment would establish a permanent total enclosure through the use of negative pressure, increase the number of emission control stages and combine existing emissions stacks into one common stack at the facility, according to Sterigenics, which is owned by Sotera Health. Sterigenics would also add a continuous emissions monitoring system, which the company said has not been employed before at any plant that uses ethylene oxide. Preliminary modeling shows that the installation of new emissions controls will further reduce the 0.1% of remaining emissions at the Willowbrook facility to minimal levels, the company said.

“By implementing these new controls, our Willowbrook facility will outperform the requirements in the recent Illinois (EO) law,” Sterigenics president Philip Macnabb said in a news release. “Additionally, Willowbrook will operate with the highest control level for (EO) emissions in Illinois and in the country, once again demonstrating our commitment to go beyond regulatory requirements.

The move by Sterigenics also comes in advance of a regulatory upgrade for EO emissions by the U.S. EPA, due this summer. The federal agency in February published proposed amendments to the National Emissions Standards for Hazardous Pollutants in the Federal Register, including ethylene oxide in a document proposed regulations for hydrochloric acid. The EPA’s latest EO proposal, since separated from the hydrochloric acid proposal, seeks comment on the science-based health risk of EO.

The EPA’s last formal rule governing EO came out in 2006. Ten years later, the agency changed the sterilant’s classification from “possibly carcinogenic” to a determination that long-term exposure could cause elevated risks for certain cancers, including non-Hodgkins lymphoma, myeloma, lymphocytic leukemia and breast cancer. That change prompted howls of protest from the sterilization and medtech industries, including the medtech trade group AdvaMed.

The Ethylene Oxide Sterilization Assn.’s website says the EPA’s conclusions about the cancer risk posed by EO are overstated and therefore flawed. The association also claims that the EPA did not take into consideration other sources of EO in the environment in reaching its conclusions. The American Chemistry Council’s ethylene oxide panel also claims that the EPA vastly overestimates the cancer risk from inhaled EO.

The federal EPA will likely collect emissions data from every facility listed as a source of EO and perform a risk assessment, said Penelope Fenner-Crisp, a former senior science advisor to the director of EPA’s Office of Pesticide Programs. Ethylene oxide is an EPA-registered pesticide, but its use also falls under the jurisdiction of the FDA.

“If the data exceeds the level of concern, they’ll come back with recommendations for mitigation and the affected parties will complain even more than they did for the carcinogenicity,” added Fenner-Crisp, one of more than 400 former EPA staffers involved with the activist group Environmental Protection Network. The assessment will apply to all EO facilities and the agency will work with each one that is out of compliance at that point, Fenner-Crisp explained. Those conversations will likely cover mitigation possibilities and alternatives to EO, she said.

Ethylene oxide is a colorless, odorless gas popular for medtech sterilization because it works at low temperatures and can penetrate device packaging, speeding the process and keeping costs down. Alternatives to EO include nitrogen dioxide, another low-temperature, gaseous sterilization method, and vapor-based peracetic acid, according to an industry expert who requested anonymity. Another low-temperature option, gamma sterilization, can alter the chemical makeup of some devices, making them brittle and discoloring them, according to David Gilbert, EO sterilization consulting study director for Nelson Laboratories. Gamma may also compromise some electronic components’ functions, he added.

Medtech sterilization method selection depends on several factors, including material compatibility, process availability, processing location, physical device attributes, legacy regulatory approval, processing volume, speed to market, cost and regulatory registration within the countries in which the medical device or products are to be distributed and used, according to the Gamma Processing Industry Alliance. Once a sterilization process is selected, it must be validated and approved by the FDA.

Changing the sterilization method for a device can be costly and take many years, the alliance said in a 2017 white paper. Risk aversion in healthcare markets and the complexities of securing FDA approval for devices that have many previous iterations have prompted the medtech industry to stick with traditional methods such as EO and gamma radiation, the group said.

AdvaMed has been lobbying hard to prevent stricter EO regulation. In an April letter to the U.S. EPA, the group said EO is used to sterilize “hundreds of millions” of devices annually in the U.S.

“Many of these devices cannot be sterilized in any other way because of the sensitive nature of the device materials, the components, or the complexity of design,” the letter said. “The majority of these devices are not resistant to damage caused by moist heat, radiation, and other modes of sterilization.”

Devices that can only be sterilized using EO include implantable devices containing electronic components and batteries, anesthesia products, combination products (devices that contain drugs), MRI conditional/safe devices and IV devices, the group added. “For a number of other types of products, our members utilize other modes of sterilization, such as gamma irradiation and electron beam sterilization when possible, but for many devices, there is currently no viable alternative technology to (EO).”

“Our focus is on acting in the best interest of the community, our employees, our customers and the patients and hospitals we serve every day,” Sterigenics’ Macnabb told us. “We are taking these additional steps to reassure the public while moving toward a solution which enables us to resume the critical work of sterilizing vital medical products and devices in Willowbrook for patients in Illinois and beyond.”

Sterigenics declined to reveal how much the upgrades to the Willowbrook plant would cost.

“We are making a significant investment to implement these upgrades consistent with our commitment to go beyond regulatory requirements but are not going to comment on the details,” spokeswoman Kristin Gibbs said in an email to us. “We are prepared to move quickly once the permit is approved and expect to install the new equipment as soon as is practicable. Through the permit, the new controls will be authorized by IL EPA, and there will be monitoring requirements associated with our operations. IL EPA inspects the facility routinely.

“No comment on the financial impact on the business, however what is more concerning is the impact this has had on the healthcare supply chain which is feeling the pain every day,” Gibbs said.

Sterigenics said it will continue to pursue its lawsuit against the Illinois EPA, seeking to reopen the plant.