Mr. Radermacher, your company offers turnkey ethylene oxide sterilization systems for its customers. Can you explain the process?
Patrick Radermacher: Our clientele includes medical device manufacturers and sterilization service providers. We are experts in the design, construction, on-site installation, and commissioning of ethylene oxide sterilization systems. This process is one of two industrial sterilization processes. Between 50-55 percent of all medical devices produced in the world are sterilized using ethylene oxide gas. The other industrial process is radiation sterilization.
Ethylene oxide gas is introduced into a hermetically sealed chamber, which houses the ready-to-be-sterilized medical devices. The gas penetrates the different types of packaging and destroys most bacteria, viruses, and microbes (fungi) on the surfaces of the devices. This means cellular reproduction is disrupted at the microbiological level, thereby sterilizing the products.
After sterilization, the packaging for medical devices ensures safe handling at medical practices and hospitals, preventing the risk of contamination of the equipment as this would have catastrophic consequences for the patients. Non-sterile medical devices could lead to infections during treatment.
Does the gas sterilize both the outer layers of packaging and the package contents?
Radermacher: The primary packaging of medical devices contains a barrier or foil that is partly gas-permeable – the so-called Tyvek film. The gas slowly works its way through the various cardboard layers, through the Tyvek film of the primary barrier, all the way to the medical devices. In doing so, both the medical devices and the complete packaging are sterilized.
What devices are sterilized with ethylene oxide? Are there exclusion criteria?
Radermacher: Ethylene oxide sterilization is product neutral and does not cause changes to the physical and mechanical properties of the materials in medical devices. It is a so-called cold gas sterilization process (with temperatures typically between 45 and 55°C), which makes it ideal for the sterilization of so-called thermolabile and single-use medical devices. For obvious reasons, the latter cannot be disinfected using hot steam sterilization (at sterilization temperatures of about 130°C). The use of radiation sterilization (gamma or x-ray) is also limited, as this process adversely affects the physical and chemical properties of certain plastics during the sterilization process – for example, PVC becomes brittle after intensive irradiation.