EPA has added ethylene oxide to the pollutants that will be measured at all existing, longstanding monitoring sites in the National Air Toxics Trends Stations and the Urban Air Toxics Monitoring Program networks. These 34 sites include the sites where EPA has already detected ethylene oxide in the outdoor air, along with sites that have not begun sampling for the chemical. For some sites, EPA is training laboratories to analyze air samples for ethylene oxide. This work will help us understand whether ethylene oxide levels vary seasonally and regionally.

Below are links to a map of the air toxics monitoring networks and summary data from 18 monitoring sites in nine states gathered between October 1, 2018-March 31, 2019. Moving forward, data from all of these sites will collect information about ethylene oxide concentrations.

• Map of NATTS/UATMP sites (PDF)(1 pg, 248 K)
• Data Summary -- Oct 2018 - Mar 2019 (PDF)(1 pg, 88 K)