Gamma Radiation Sterilization: A Key Weapon in Bacteria & Microorganism Elimination
The most popular form of radiation sterilization, gamma radiation sterilization, is a process used throughout many industries. Though it’s most commonly associated with the medical industry, it's also used in fighting infestations in agricultural products, on product packaging, for reducing microbial contamination on certain foods, and more. It can also be used to sterilize personal protection equipment (PPE) for reuse by professionals throughout a variety of industries.
Gamma Radiation Sterilization Explained
As the name implies, this is a sterilization process, and it's commonly used to kill bacteria and microorganisms that may be living on the surface of products, packaging, or goods. Powered by Cobalt-60, the low-dose process is administered when high-energy photons are emitted from a radiation source, which works to ionize the product or item in question.
Ionization causes disruptions to any cellular structure that it comes into contact with, destroying organisms at the molecular level and making it impossible for them to reproduce. Essentially, the process works to alter a microorganism’s DNA so that it's destroyed and unable to multiply.
The process has been in effect since the 1950s and is commonly carried out in continuous or batch formats. In a continuous format, item(s) pass through an automatic conveyor system where they're exposed to radiation-- in this case, gamma rays. This process is commonly utilized on large sums of products at a time.
The batch process works a little differently, commonly consisting of loading one or more totes into a radiation chamber for treatment. It's often used to treat groups of products/items on an as-needed basis.
What Industries Use Gamma Radiation Sterilization?
The gamma sterilization process is commonly used in the medical industry to disinfect certain tools and products (i.e., implantable medical devices, surgical gowns, etc.). "Sterile" by medical terms, is defined as free from bacteria or other microorganisms to the point where they cannot reproduce and create any further contamination.
As you might expect, performing surgery or a procedure on a patient with contaminated medical tools has the potential to lead to infection or further complications. This is why medical tools are required to be properly sterilized prior to use.
The method can also sterilize personal protective equipment (PPE) both before and after use, so it can be used again. Aside from use in the medical industry, gamma sterilization also proves beneficial when working with:
- Certain packaged goods
- Pharmaceutical packaging and products
- Raw materials
- Certain foods
- Agricultural applications
Gamma Radiation Sterilization Advantages and Disadvantages
Advantages of Gamma Radiation Sterilization
When administered correctly, gamma sterilization is safe and effective. In fact, it's backed by ISO 11137, the internationally recognized standard to achieve a defined sterility assurance level or SAL. Gamma radiation has several advantages over other sterilization methods. It offers better (deeper) penetration, a higher certainty of sterility, and its effectiveness is independent of temperature and pressure conditions.
It's Easy to Administer
This sterilization method is fairly easy to administer. In fact, only the sterilization dose or "radiation dose" and exposure time are required to be monitored by those who oversee the gamma sterilization process. This makes it relatively easy to learn and execute.
The biggest advantage of the gamma sterilization process is that when it's used correctly, it's both efficient and effective. While the process can take hours in some industries for certain applications, effective sterilization in others can be performed relatively quickly. For instance, certain products can be sterilized in a matter of seconds.
No Negative Environmental Impact
After the process, the products and items treated are not radioactive, which tends to be a common misconception. Additionally, there is no negative environmental impact resulting from this process.
Gamma sterilization is able to penetrate deep into items, which makes it ideal for cleansing a wide range of products, no matter the density, orientation, or type of material. It can also work on products that have already been packaged, further reducing the risk of contamination after sterilization. This process is also suitable for more than just solid dry goods; it works well on frozen materials as well.
Simply put, gamma radiation sterilization can help ensure sterility assurance, giving those associated with the product or items the peace of mind that what they're wearing, handling, consuming, producing, or distributing is safe.
Disadvantages of Gamma Radiation Sterilization
While many industries use this method to sterilize products, goods, and items, it's not suitable for certain applications.
- It doesn't work well on liquid products due to the potential for product degradation
- Foods that are high in fat are often not good candidates to be treated using this method
- It may discolor or alter the texture of certain products
Though the gamma sterilization process is internationally recognized as a way of effectively and efficiently treating products and items, there are some potential safety concerns to note. As you might expect, any process that uses any sort of radiation is going to present some risk if it's not administered properly — and that's one of the major safety hazards associated with gamma processing. Hence, if the process is carried out incorrectly, workers risk the potential for harmful exposure to radiation.
However, it's worth noting that facilities that do administer this method are regulated and operators are required to undergo training to ensure that they're following safety protocols. Furthermore, the manufacturing and treatment of any medical product is regulated by the U.S. Food and Drug Administration (FDA) and foods are regulated by the U.S. Department of Agriculture (USDA).
There are a few other safety concerns to note with the method. For instance, this process has the potential to damage or discolor the material or item that is being treated. It may also create irregular changes in material, including properties such as color, solubility, and texture. These potential drawbacks demonstrate the importance of proper training to ensure the method is used correctly and safely where and how it is administered.
One of the many ways that gamma sterilization has gained prominence over the past year is when it comes to sterilizing PPE for re-use. The use of this process became critical when the COVID-19 pandemic erupted, and medical workers scrambled to find adequate amounts of PPE and medical devices to care for patients that flooded hospitals.
According to the International Atomic Energy Agency (IAEA), the method is effective in sterilizing all PPE aside from respiratory masks for reuse. But why not respirator face masks? The IAEA discovered that the radiation had the potential to weaken the respirator component of the covering making it less effective.
Aside from the medical industry, sterilization prior to re-use (or even initial use) plays a role in other industries as well. Restoration workers can re-use certain pieces of PPE for abatement jobs. Industries such as construction and emergency response can also benefit from this process. While the gamma sterilization method isn't suggested for treating respiratory masks, it can be used for other types of masks and facial coverings, which can help more than just medical workers.
Overall, with proper training, it's safe, effective, flexible, and a highly efficient means of eliminating bacterial contamination and microorganisms from some of the world's most essential products and goods.
Sterile PPE for Pharmaceuticals, Controlled Environments, Cleanrooms, and more
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