No specific regulatory legislation exists in Italy on the use of ethylene oxide. Studies were carried out to determine the concentration of ethylene oxide to which workers are exposed, potential pollution hazards from ethylene oxide and Freon 12, effectiveness of the treatment, presence of ethylene oxide and Freon 12 residues in paper after treatment, the desorption time for paper with regard to ethylene oxide and Freon 12. Standard sterilization and disinfestation procedures are described. Experiments were carried out using both mobile and immobile systems. The work concluded that the neutralization system for the sterilization mixture at the end of the treatment is either absent or ineffective, significant quantities of ethylene oxide remain in the autoclaves after treatment, residual amounts of ethylene oxide and Freon 12 still remain in the paper, and treatment is not always effective. Further research is being carried out.