Introduction
The globe is currently experiencing the fourth revolution in history, characterized by technological advancements. Innovation now permeates every element of human life and is on track to become indispensable to human existence. As with other industries, technology has had a significant impact on healthcare during the last several decades. One area that has puzzled many is the use of nuclear technology in medicine, which relies on radio-pharmaceuticals.
The purpose of this research is to examine the usage of cobalt-60 (Co-60), which has helped to improve the quality of medical therapy. It is primarily beneficial in cancer, where it is delivered via gamma radiation therapy. Despite its environmental consequences, such as radioactive contamination, cobalt-60’s societal benefits, notably in medicinal applications, significantly outweigh its disadvantages.
Background Information
Radioactive Versus Non-Radioactive Isotope
Isotopes are atoms, the smallest units of material that preserve a compound’s chemical composition. Each element in an isotope is differentiated by the quantity of protons, neutrons, and electrons it contains. Each chemical element’s atoms have the same number of protons and electrons, but not neutrons, which can vary, and this also applies to isotopes.
Stable isotopes do not release radiation and are considered non-radioactive, while unstable isotopes do, making them radioactive. According to the Centers for Disease Control and Prevention (CDC, 2023), Co-60 has a half-life of 5.27 years. This is the time it will take for the radioactive substance to lose approximately half of its radioactivity through decay.
Naturally Occurring Versus Synthetic Isotopes
A radioisotope’s unstable nucleus might occur naturally or as an outcome of an artificially altered atom. There are over 3000 known radioisotopes, with uranium being the most commonly naturally occurring (Fassbender, 2020). However, it is extremely difficult to distinguish this small amount from the much larger bulk of other types of uranium, since they all have the same number of electrons and exhibit identical chemical activity.
A more efficient way is to artificially create radioisotopes, which is typically done in nuclear reactors. This is accomplished by shooting high-speed particles into the core of an atom. When struck, the nucleus may absorb the particle or become unstable, emitting a particle that forms a new isotope.
Radioactive Isotopes General Medical Applications
Radioisotopes release varying amounts of radiation, making them valuable in medicine. They are crucial components of radio-pharmaceuticals, which deliver radiation for detection-based radiography or specialized therapy. Small doses of radiation are used to offer insights into a person’s body and the workings of certain organs, ongoing biological functions, or the current status of a specific sickness (Nagai, 2021). Radioisotopes have been used for decades to manage cancer and other chronic illnesses through radioisotope therapy. They are also used extensively in in vitro diagnosis, and to develop safer healthcare goods by eliminating or neutralizing hazardous substances, germs, and poisons.
Use of Cobalt-60 in Medicine
Co-60 is a hard, gray-blue solid that is similar to iron or nickel and can occur naturally or be commercially produced. It can become magnetically charged, making it suitable for a variety of medical applications. It is mainly utilized in radiation therapy, both as implants and as an outside source of radiation. Co-60 is also used to sterilize medical equipment such as sutures, gloves, and syringes (Uccelli et al., 2022). This form of Cobalt-60 is commonly obtained from nuclear firms. Gamma sterilization is a well-established method for sterilizing single-use medical items.
Orthopedic devices, such as knee replacements, stents, and heart valves, are examples of implantable devices. Metals and polymers pose problems with certain sterilization methods, but gamma radiation is highly effective for sterilizing implantable devices. Indicates that it accounts for the majority of orthopedic sterilization methods (Chibonda et al., 2021). Given the high cost of many implantable devices, a reliable method, such as gamma radiation, is required to ensure quality control and prevent product loss.
Environmental Impact and Management
Impacts
The majority of the globe’s cobalt lies in its core. However, it can be found in relatively low quantities in the Earth’s crust. It is also present in natural waterways, where it precipitates as extremely insoluble cobalt sulfide (CoS). Given that cobalt is widely distributed in the natural environment, humans may come into contact with it through breathing, drinking water, and eating cobalt-containing foods. Contacting the skin with soil or water containing cobalt may enhance people’s exposure. It may not be readily available in the surrounding environment, but when cobalt fragments are not attached to soil or sedimentary particles, plants and animals are more likely to absorb them, leading to buildup.
When plants grow in contaminated soils, they accumulate extremely small cobalt particles, particularly in parts of the plant that humans consume, such as fruits and seeds (Nagai, 2021). Soils near mining and melting operations may contain exceedingly high levels of cobalt, which humans can absorb through eating plants, causing visual issues, thyroid damage, heart problems, vomiting, and nausea. The radiation can result in infertility, hair loss, nausea, bleeding, hemorrhage, diarrhea, coma, and even death. Cobalt dust can induce an asthma-like condition with symptoms including coughing, shortness of breath, dyspnea, impaired pulmonary functioning, nodular fibrosis, permanent impairment, and even death. Cobalt exposure could end up causing weight loss, rashes, and pulmonary hypersensitivity.
Safe Disposal and Storage
Cobalt cannot be removed once it enters the environment, making it difficult to dispose of because of its radioactivity. It may react with different particles or be adsorbed onto soil or water sediments. Cobalt will only dissolve in acidic conditions; however, the majority will end up in soils and sediments. Disposal is simple, as it is non-toxic and comes in double-encased stainless steel capsules. It has a shorter half-life than most radioactive elements, decays rapidly into Nickel-60, and has no immediate biological or environmental effects (Uccelli et al., 2022).
High security and risk classification standards may be employed to the greatest possible extent to prevent unauthorized access and acquisition. Nagai (2021) indicates that Co-60 must be stored in an area properly protected by lead or uranium, preferably in a highly protected container. Enclosed sources pose no radiation exposure risk unless the sealed source loses containment, and all care should be taken to avoid inhaling or ingesting the material. Sealed radioactive sources that are used in industrial processes should always be contained within an armored source housing to reduce radiation exposure and protect the source capsule from damage.
Benefits to Society
Cancer Treatment
Co-60 systems have spurred significant technological advances, particularly in cancer management. For example, the Gamma Knife is a technique in which specialized equipment directs nearly 200 small beams of radiation via circular pinholes in a helmet worn by the patient (Uccelli et al., 2022). Pinhole radiation delivers high doses to the tumor while sparing healthy tissue and key brain structures. Although each beam has minimal impact on the brain’s healthy tissue as it passes through, a high dose of radiation is transmitted to the point where all the beams intersect. These systems have been proven effective for decades.
The approach remains the sole specialized radio-surgery technique available for the therapeutic management of brain metastases. Gamma Knife radio-surgery is typically a one-time procedure that takes only one day and often serves as a safer alternative to standard brain surgery. Another approach entails the use of stereotactic radio-surgery in combination with Co-60 therapy (Uccelli et al., 2022). The combined effort enables doctors to administer larger doses of radiation to tumors while minimizing damage to healthy tissue and organs.
Other Benefits of Radioisotopes
Radioisotopes are used in nuclear imaging to improve diagnosis by detecting gamma rays generated from within the body. The approach differs from other medical imaging technologies, such as Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and X-rays, which use radiation emitted within the body (Chibonda et al., 2021). Nuclear imaging shows the location and concentration of the radioisotope.
If just a tiny amount of the radioisotope has been taken up, a cold spot will appear on the screen, suggesting that blood is not passing through. A hot spot, on the other hand, may suggest excessive radioactive uptake in a tissue or organ, which a disease, such as infection or cancer could cause. This method works well for imaging both bone and soft tissue.
Conclusion
The incorporation of Co-60 into medical practice underscores the enormous impact of technological advancement on healthcare during this period of innovation. Despite initial criticism of the use of nuclear technology in medical treatment, Co-60 has become an important tool for improving healthcare quality, particularly in cancer treatment. Co-60 gamma radiation therapy provides accurate and effective treatment for malignant cells, as demonstrated by techniques such as the Gamma Knife, which minimize damage to healthy tissue while targeting tumors with remarkable accuracy. However, it is critical to recognize the environmental implications of Co-60, which include radioactive contamination. Nonetheless, the social benefits of Co-60, such as improved cancer treatment results and diagnostic capabilities using nuclear imaging, greatly outweigh the downsides.
References
Centers for Disease Control and Prevention (CDC). (2023). Radiation emergencies – Radioisotope brief: Cobalt-60 (Co-60).
Chibonda, S., Ndlovu, N., Tsikai, N., Munangaidzwa, L., Ndarukwa, S., Nyamhunga, A. & Mazhindu, T. (2021). High dose rate intra-cavitary brachytherapy with cobalt 60 source for locally advanced cervical cancer: The Zimbabwean experience. Infect Agents Cancer 16.
Fassbender, M. E. (2020). Radioisotopes and radiochemistry in health science. Scientific Reports, 10(1).
Nagai Y. (2021). Production scheme for diagnostic-therapeutic radioisotopes by accelerator neutrons. Proceedings of the Japan Academy. Series B, Physical and biological sciences, 97(6), 292–323.
Uccelli, L.; Martini, P.; Urso, L.; Ghirardi, T.; Marvelli, L.; Cittanti, C.; Carnevale, A.; Giganti, M.; Bartolomei, M.; Boschi, A. (2022). Rhenium radioisotopes for medicine: A focus on production and applications. Molecules, 27.