Ethylene Oxide: Techniques for Sample Collection and Overcoming the Challenges of the Analysis.

Air Monitoring, Methods, and Technology
Oral Presentation

Prepared by H. Calder, L. Miles
Markes International, 1000B Central Park, Western Avenue, Bridgend, (State/Province), CF31 3RT, United Kingdom


Contact Information: [email protected]; 01443230935

ABSTRACT

The health risks associated with exposure to ethylene oxide have been highlighted since 2016 when the EPA updated their risk estimates on the chemical. Long term exposure to ethylene oxide has been shown to increase the risk of developing certain cancers and as such it is now important that ethylene oxide is measured in a broader context than it has been previously.

To truly understand exposure it is important to look at the background air concentrations, emissions from industry and undertake monitoring within at risk communities. Thermal desorption (TD)/pre-concentration equipment combined with GC-MS is the gold standard analytical method for sampling and analysis of ethylene oxide in air. TD enables multiple sampling methods to be used such and active and passive sampling onto sorbent tubes and collection of whole air samples in canisters and bags. This helps the technique to be applicable to each of the sampling scenarios outlined which all have very different requirement and can poses a challenge when designing a sampling campaign. Another advantage is the inherent pre-concentration effect of the technique. With no need for dilution of the sample very low (ppt) limits of detection can be reached for ethylene oxide.

However the analysis is not without its challenges. Ethylene oxide can be difficult to chromatographically resolve from interferences with similar chemistry which can effect quantitation. It has also been shown to be released from some canisters introducing bias and increasing minimum method detection limits for the analysis. Within this presentation we will discuss the challenges outlined and share results from research to try and solve them using TD-GC-MS.