In-vitro analysis of the cellular toxicity of PVC tubes consecutively sterilized with gamma rays and ethylene oxide

• Grant number: 09/10345-0
• Support Opportunities: Regular Research Grants
• Start date: October 01, 2009
• End date: September 30, 2011
• Field of knowledge: Health Sciences - Nursing - Medical-Surgical Nursing
• Principal Investigator: Kazuko Uchikawa Graziano
• Grantee: Kazuko Uchikawa Graziano
• Host Institution: Escola de Enfermagem (EE). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

In 1967, a letter sent to the British Medical Journal reported that the re-sterilization with ethylene oxide (EtO) of polyvinyl chloride (PVC) that had been previously irradiated with gamma-rays formed "large amounts of ethylene chloridrine". Even without containing measured data, this letter initiated a dispute that, to date, divides the opinions of researchers, who have so far presented controversial results regarding the issue. It is important to clarify this doubt, as gamma-irradiated PVC products for prompt use are usually re-sterilized with EtO in case of expired sterilization date, which is determined by the manufacturer. This study aims at demonstrating the cellular toxicity of PVC materials through the agar diffusion test in NCTC clone 929 cell cultures. Four comparative groups will be created: G1, G2, G3 and G4. G1 will consist of "in natura" PVC tubes, G2 of gamma-ray irradiated PVC tubes, G3 of PVC tubes sterilized in ethylene oxide and G4 of PVC tubes that were irradiated by the manufacturer and re-sterilized in EtO after re-packing. The initial hypothesis is that the cellular toxicity of the tubes in G4 will be higher in comparison to the ones in G1, G2 and G3 groups. (AU)