Dr Dave:
You are correct that ethylene oxide is readily available and in most states
for hospital use.
However, EPA has only issued licenses to Mayland, North Carolina, and Maine
for use of ETO on honey bee equipment.  Although Maryland has had a  portable
ETO fumigation chamber in use for many years, EPA has now Reinterpreted their
rather wild regulations, so that to date, Maryland has not been allowed to
purchase Ethylene Oxide yet this year.  Another shining example of "someone
looking over your shoulder".
                                                                                George Imirie