Collaboration with the South Coast Air Quality Management District
The Vernon facilities operate in compliance with current regulations, and Sterigenics continues to work proactively with SCAQMD to further reduce emissions. Sterigenics has successfully completed remediation efforts to address the previously announced SCAQMD notices of violation. Other near-term measures are in progress, including additional fugitive emissions capture projects at both the 49th and 50th Street facilities. The longer-term commitment is to make both facilities permanent total enclosures, operating under negative air pressure and routing all inside air through an enhanced emission control system that improves on the high efficiency of the existing system. Sterigenics is working with AQMD to put these measures in place as quickly as possible, recognizing that some of the steps in that process are beyond the control of the facility, including City and AQMD permitting for facility upgrades and access to contractors and equipment.
Sterigenics operates safely and in compliance with regulatory requirements
Sterigenics consistently complies with environmental permits issued for each of its sterilization facilities. Sterigenics has disclosed its EO emissions for decades in federal and state filings – even when not required and when others in the industry did not – and has a track record of implementing leading safety practices to further perform better than regulatory requirements.
-
NESHAP are stationary source standards for hazardous air pollutants. The regulation sets standards for allowable emissions levels, as well as a framework for ongoing compliance and inspection (i.e., reviewing records, inspecting facilities, interviewing personnel).
The medical sterilization industry has been anticipating an update to EO regulation under NESHAP for multiple years. A notice of proposed rulemaking is anticipated during 2022, with a final rule to follow completion of the rulemaking process. Sterigenics is making investments today to best position its EO sterilization facilities for compliance with future regulations.
Controversy over the use of EO
-
Recent controversy related to EO is ultimately grounded in a study published in December 2016 by EPA’s Integrated Risk Information System program (IRIS). IRIS assessments are a source of information used by EPA, state and local health agencies, other federal agencies, and international health organizations. It is not a safety limit and is not intended to be a regulatory standard.
In 2016, EPA’s IRIS group completed a review and reclassified EO from “Probably Carcinogenic” to “Carcinogenic” and updated its inhalation unit risk estimate. During this multi-year review, EPA’s independent Science Advisory Board (SAB) raised several questions about the basis for these conclusions. The IRIS group’s final report failed to resolve those questions.
The IRIS update gained attention in 2018, when the EPA used it to evaluate nationwide cancer risks as part of its National Air Toxics Assessment (NATA). NATA’s computer-simulated assessment combined the widely disputed IRIS inhalation unit risk estimate with outdated 2014 public emissions data from facilities across the country that are not always reflective of current emission control systems. This flawed analysis implied that 106 census tracts across the country, including the Sterigenics facilities located in Willowbrook, IL, Smyrna, GA, and Santa Teresa, NM, were identified as having an elevated risk of cancer due to EO, including several locations near other medical sterilizers that use EO.
The EPA has recently agreed to reconsider the use of the IRIS value for EO in assessing cancer risk for the source category
-
The IRIS value of 0.1 parts per trillion of EO is an inhalation unit risk estimate, which assumes that inhaling EO 24 hours per day, 7 days per week for 70 years might increase the risk that 1 additional person in 1 million will get cancer.
The IRIS program has been widely questioned in the past by reputable organizations such as the Government Accountability Office and a National Academy of Sciences panel. EO exists naturally at concentrations significantly exceeding the IRIS value, including in the human body.
