Medical Device Sterilization: 4 Alternatives to Ethylene Oxide

With thanks to Emily Lorcheim of ClorDiSys Solutions for her contributions.

Ethylene Oxide (EtO) is the man-made chemical that’s responsible for sterilizing roughly half of the medical equipment used in the U.S. today. The popularity of EtO as a sterilizing agent stems from its versatility — it’s compatible with a wide range of materials, highly penetrative, and as a result of these characteristics, very convenient.

However, despite its prevalence in medical device sterilization (both throughout history and currently), the use of EtO has come under scrutiny in recent years. Mounting evidence shows that long-term exposure to Ethylene Oxide increases the risk of certain cancers, putting those who work with EtO and others who live, work, or attend classes near facilities that regularly use the chemical at particular risk. As a result, many of these facilities across the country have been shuttered while new regulations propose stricter standards for the ones that continue to operate.

These shutdowns and regulations are good news for public health and safety, but without an alternative sterilization solution in place to fill the gap left behind, the consequences for patients could be disastrous. Healthcare-associated infections (HAIs) pose a significant risk to patient safety, so proper device sterilization is essential.

As it stands, the future of the use of EtO in sterilization is uncertain. Here, we’ll highlight why it’s important to branch out and highlight four of the most viable alternatives. Read on to find out what they are.

Why Is Sterilization With Ethylene Oxide So Widely Used?

In addition to being a powerful sterilizing agent, these are some of the reasons behind why the industry has historically relied so heavily on EtO:

• It’s penetrative and can successfully sterilize instruments and devices when they’re sealed inside layered packaging.
• It’s versatile, and even moisture-sensitive medical devices can withstand it.
• It’s convenient and can sterilize a large load of devices at once without needing to remove them from boxes or other containers.

Lastly, resistance to change plays a part in the continued use of EtO. “It was really the first gaseous method out there that was used for medical device sterilization, so people got used to using it,” says Emily Lorcheim of ClorDiSys Solutions. “The medical device industry is slow in transitioning so if [EtO sterilization] works, they’re fine with keeping it.”

The Importance Of Branching Out From EtO For Sterilization

There are several reasons why it’s a good idea to explore alternative options to EtO for medical device sterilization. The first and foremost being that it’s a known carcinogen, making its emissions dangerous to those subjected to long-term exposure. Other motivating factors include:

• Its future is uncertain. As EtO use dwindles and becomes subject to tougher regulations, the volume of devices processed will decrease. Currently, there are no comparable sterilization alternatives for some medical devices, so diversification is essential.
• It’s inefficient. In order to be effective, EtO needs time to aerate (depending on the device, this can take two hours or two weeks), which results in a longer and more drawn-out process when compared to other sterilization methods.
• It’s explosive. In addition to its status as a carcinogen, EtO is both highly flammable and explosive, making it especially dangerous.

4 Alternatives To EtO Sterilization

Thankfully, the FDA is working with the medical device industry to find a comparable alternative to EtO. As for other proven sterilization methods that are readily accessible, the following four are worth considering:

Steam Sterilization

This process relies on moisture and extreme heat to sterilize instruments and devices.

• Pros: Fast acting, easy to use
• Cons: Not ideal for devices that can’t handle moisture and heat

Chlorine Dioxide Gas

In addition to being an effective sterilizing agent, ClO₂ is also used as an oxidizer and disinfectant.

• Pros: The closest gaseous alternative to EtO, compatible with most materials
• Cons: Is currently only an option for industrial medical device sterilization

Nitrogen Dioxide Gas

The unique properties of NO₂ gas allow for sterilization to occur at room temperature.

• Pros: Has the same penetrative abilities as EtO
• Cons: Can’t sterilize paper, can be harsh on some materials

Irradiation: E-Beam, X-Ray & Gamma Ray

This method uses radiation to kill bacteria by breaking down their DNA, preventing division.

• Pros: Good for materials that can’t be autoclaved and have no gas path
• Cons: Requires large equipment, not feasible to introduce this type of machinery in a hospital setting, not ideal for plastics

What Makes Steam The Best Choice For Medical Device Sterilization?

Out of all EtO alternatives, steam sterilization offers the most benefits. Not only is it just as effective as EtO, but it provides fast and efficient sterilization for metal instruments, autoclave-safe plastics, implants, and other devices that can withstand heat and moisture. Most healthcare workers are also already familiar with the associated machinery and processes, so the learning curve is very slight — if one exists at all.

Is Your Healthcare Facility on The Right Track?

Steam sterilization technology provides an excellent alternative to EtO-reliant methods and serves an essential purpose in providing comprehensive patient care. Ready to put your ambulatory surgery center sterilization setup to the test? Take our free self-assessment to see whether your current setup sufficiently meets your needs.