I think it will be ok, (poly)ethylene oxide is also an ingredient in spermicide (you know, the stuff in KY jelly.) <--These products have a pretty low hazard rating so don't worry about using them either. But I digress.
I do not believe ethylene oxide is used in the raw for manufacturing medtronic tubing, if I understand correctly it has the potential to be combined with boron trifluoride to cause a chemical reaction that produces Poly(ethylene glycol). Poly(ethylene glycol) is really amazing stuff. In theory it should keep you insulin from sticking to your tubing.
However to date I have not seen the mention of ethylene oxide being used as a lubricant by Medtronic. It's only use labeled so far is for what people use it in hospitals for, gas sterilization of medical supplies.
Read up is my best advice, having a healthy fear of chemicals is alright. I just try to use fear as a learning opportunity. If you are at a liberal University go to the chemistry department and interview them about the chemical. I have done this a number of times going to different departments when I have questions about something. Chances are, university teachers love to talk about what they teach, and they should be happy to talk about their love with you too.