Reduced EtO emissions to safeguard biomedical supply chains - Summary/Abstract
The overarching goal of this project is to protect the nation’s supply chain of critical medical
devices that are sterilized using ethylene oxide (EtO). Despite the search for alternative
approaches, numerous types of single-use devices are sterilized with EtO. These devices,
including catheters, heart valves, and tracheostomy tubes, are critical to routine and life-saving
procedures and therapies. As regulation of EtO emissions and community and worker exposure
levels continues to become more stringent, there is a threat that supply chains for critical devices
will be disrupted, in turn threatening the health and well-being of the nation. The specific
objectives of this project include the development of a novel photocatalytic method to mitigate
EtO at levels that are hazardous but difficult to address with existing adsorptive and thermal
catalytic approaches. Specifically, the technology addresses concentrations in the range of 10 ppm
and below. The technology can be used to mitigate EtO from existing sterilization plants as an
adjunct to stack scrubbers, as well as deployed to address ambient levels of EtO in plants and
warehouses. Objectives include determining operating conditions at which low concentrations of
EtO (<10 ppm) are oxidized at 99% destruction and removal efficiency (DRE), identifying
optimum photocatalyst and parameter space for achieving high DRE, developing a prototype
photoreactor operating at 20 cfm capable of 99% EtO DRE that is scalable to commercial
requirements, and evaluating the performance of the prototype for a target 99% EtO DRE at 20
cfm. The specific aims are determining operating parameters at lab-scale, building a scalable
prototype reactor capable of 20 cfm operation, and evaluating the performance of the prototype
at 20 cfm for a target of 99% EtO DRE. Study designs are centered around systematic catalyst
modifications and exploration of gas flow / illumination geometries. Standard and cutting-edge
detection approaches that are capable of measuring EtO into the low ppb and ppt ranges will be
used in the experimental program.