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Hazardous Air Pollutants: Ethylene Oxide

Frequent Questions: Regulations for Ethylene Oxide


Regulations

What is EPA doing to reduce ethylene oxide in my area and across the country?

We are taking a two-pronged approach to finding opportunities to reduce ethylene oxide emissions:

EPA is reviewing Clean Air Act regulations for facilities that emit ethylene oxide:

  • EPA has begun reviewing its air toxics emissions standards for miscellaneous organic chemical manufacturing facilities, some of which emit ethylene oxide.
  • The Agency also plans to take a closer look at its rules for other types of facilities, beginning with its emissions standards for commercial sterilizers. 

EPA is also getting additional information on ethylene oxide emissions

  • EPA also is gathering additional information on industrial emissions of ethylene oxide, which may include data from testing at facilities.
  • This information will help EPA as it looks for opportunities to reduce ethylene oxide emissions as part of its regulations review.
  • It also will help us determine whether more immediate emission reduction steps are necessary in any particular locations. We do not know yet whether those locations include the location you mentioned.

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Are the MACT standards for sterilization facilities being reviewed? Any updates in regards to the air toxics emissions standards for MON?

EPA has existing rules for industries that emit ethylene oxide, and we have begun to review those.  EPA is currently conducting a Risk and Technology Review (RTR) for the Miscellaneous Organic National Emissions Standards for Hazardous Air Pollutants (also known as the MON). The agency has a court-ordered deadline that requires the MON RTR be finalized by March 13, 2020. We expect a proposed rule in the summer of 2019. We are also beginning work to look at emissions standards for commercial sterilizers.

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Why haven't permissible standards in emissions at the F/S/L level conformed to align with this acknowledgement of environmental pollutant and public endangerment?  When will this conform and affect permitting, etc. as is the case when a law changes?

The Clean Air Act requires EPA to protect air quality and directs different approaches to address different types of air pollution.  Ethylene oxide is a hazardous air pollutant, also referred to as a toxic air pollutant or air toxic. There are 187 different toxic air pollutants regulated by EPA.  They are known to cause cancer and other serious health impacts such as reproductive effects or birth defects.  EPA does not set air quality standards for these pollutants, but rather develops emission standards specifically for those industrial facilities that emit them in two phases. 
  • The first phase is “technology-based.” EPA develops emissions standards for controlling air toxics from sources in an industry group (or “source category”). These emissions standards, called maximum achievable control technology (MACT) standards, are based on emissions levels that are already being achieved by the best-controlled and lowest-emitting sources in an industry. 
  • The second phase is “risk-based.” Within eight years of setting the MACT standards, the Clean Air Act directs EPA to assess the remaining health risks from each source category to determine whether the MACT standards protect public health with an ample margin of safety and protect against adverse environmental effects. In this phase, EPA must determine whether more health-protective standards are necessary.

Also, every eight years after setting the MACT standards, the Clean Air Act requires that the EPA review and revise the MACT standards, if necessary, to account for improvements in air pollution controls and/or pollution prevention.

EPA is currently reviewing Clean Air Act regulations for facilities that emit ethylene oxide including commercial sterilizers and miscellaneous organic chemical manufacturing facilities.

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EPA is influenced by the entities they regulate. This is clear from the record and self-evident in reviewing comment periods and the time elapsed from initial findings to adoptions of new rules. What can be done to eliminate the influence industry has on EPA?

For regulatory programs, EPA often has discussions early in the rulemaking process with government partners (federal, state, local and tribal) and with interested parties such as affected industries, environmental groups, and communities. After a rule is complete, EPA works with government partners and stakeholders to achieve effective implementation.

EPA's regulatory work under the Clean Air Act guarantees that every citizen has opportunities to provide comments on any air pollution rule proposed by EPA. 

EPA publishes every proposed rule in the Federal Register. Any citizen can provide written comments on any proposed rule, and these comments are placed in an electronic docket. EPA must respond in writing to each substantive comment and must place its responses in the docket, the official rulemaking record.

EPA also must offer the opportunity for public hearings on proposed air quality rules.

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Is the EPA planning on setting regulations for EtO and what is the expected timeframe? What regulations are they working on, handling as well as emissions?

EPA has existing rules for industries that emit ethylene oxide, and we have begun to review those.  We are starting with our air toxics emissions standards for miscellaneous organic chemical manufacturing facilities, some of which emit ethylene oxide. We also are beginning work to look at emissions standards for commercial sterilizers.

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What does the EPA think of the Ontario Canada standards for ambient air concentration published in 2007 based upon their own work and review of various standards including North Carolina and California?

EPA’s 2016 unit risk estimate (URE) for ethylene oxide is based on the best available science and follows the EPA guidelines. Ontario’s 2007 air quality standards for ethylene oxide are based on animal carcinogenicity data and do not take into account data on occupational exposures to ethylene oxide. Ontario’s standards were being developed at the same time the U.S. EPA was conducting its revised toxicity assessment of ethylene oxide. EPA’s revised assessment concluded that ethylene oxide is a known human carcinogen and established a URE that is based on human data.

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