Environmental Source Samplers, Inc.
EPA Proposes Utilizing 2016 IRIS Value EtO Emissions
The U.S. Environmental Protection Agency (EPA) is proposing to reconsider ethylene oxide (EtO) emissions the August 2020 National Emission Standards for Hazardous Air Pollutants (NESHAP) for chemical plants that fall under the Miscellaneous Organic Chemical Manufacturing source category , 40C CFR Part 63 Subpart FFFF. The NESHAP for the miscellaneous organic chemical (MON) manufacturing industry established emission limits and work practice standards for new and existing miscellaneous organic chemical manufacturing process units, wastewater treatment and conveyance systems, transfer operations, and associated ancillary equipment and implemented section 112(d) of the Clean Air Act (CAA) by requiring all major sources to meet hazardous air pollutants (HAP) emission standards to reflect application of the maximum achievable control technology (MACT).
EPA’s peer-reviewed value showed that ethylene oxide (EtO) was significantly more toxic than previously understood. The agency is proposing this action because the 2016 ethylene oxide Integrated Risk Information System (IRIS) assessment remains the best available science.
In this reconsideration action, EPA is addressing these two issues and is proposing the following:
- To not change its decision to use EPA’s 2016 IRIS value for ethylene oxide when assessing risk for the source category in the 2020 MON final rule, as the 2016 ethylene oxide IRIS assessment remains the best available science;
- To decline to use the TCEQ risk value for ethylene oxide instead of the EPA’s 2016 IRIS value, after careful consideration of the TCEQ risk value for ethylene oxide.
As such, EPA is not proposing any changes to our risk assessment for the 2020 MON final rule.
EPA is moving ahead with actions under the Clean Air Act that will address air emissions of ethylene oxide. The agency is currently undertaking a review of a rule for commercial sterilizers, which will consider risk, and expects to issue a proposal in 2022. EPA intends to use the 2016 IRIS value in the upcoming proposed rule for sterilizers. The agency has been collecting information about the source category, including Information Collection Requests (ICR) under the Clean Air Act. The deadline for commercial sterilizers to submit their most recent ICR response was November 2021. EPA is evaluating that data now.
Learn more: 40 CFR Part 63 Subpart FFFF
The U.S. EPA signed an amendment to the rule on February 28, 2022 that removes the stay of the formaldehyde limit for lean premix and diffusion flame gas-fired units that were constructed or reconstructed after January 14, 2003.
The U.S. Environmental Protection Agency (EPA) is proposing to reconsider ethylene oxide (EtO) emissions the August 2020 National Emission Standards for Hazardous Air Pollutants (NESHAP) for chemical plants that fall under the Miscellaneous Organic Chemical Manufacturing source category , 40C CFR Part 63 Subpart FFFF.