1. What is used to sterilize masks?

Medical masks are sterilized in a variety of ways including with steam, radiation, ethylene oxide and other methods.

Most of the medical and N95 masks available on the market are sterilized by ethylene oxide (EtO). It is an important sterilization method that manufacturers widely use to keep medical devices safe.

2. Can ethylene oxide residue on masks cause immediate/acute health effects?

Only long-term and occupational exposure to EtO has been linked to cancer in research studies.

For major manufacturers that follow production standards and guidelines, the level of residual EtO left on a mask after it has undergone EtO sterilization is within safe limits.