The purpose of this article is to assess the environmental sustainability of current technologies used for disinfecting medical equipment and it provides an example of an environment-friendly disinfecting technology namely, Ultraviolet (UV) light. These currently commonly used techniques are shown to be hazardous to the environment and public health. 

Using UV light to disinfect medical equipment while still satisfying environmental and public health standards, makes it a possible substitute for currently prevalent treatment and disposal techniques.

Background

Medical waste is a specific pollutant with infectious, contaminating, and hazardous properties that are created by health care facilities throughout the process of medical diagnosis and treatment. As per the World Health Organization (WHO), at least 15%  of medical waste is classified as hazardous material, which might be infectious, toxic, or radioactive. When compared to regular solid waste, medical waste carries a larger threat of environmental contamination since it often contains a high concentration of viruses, bacteria, toxins, and even radioactive elements. For example, approximately 16 billion injections are given worldwide each year, yet not all of the needles and syringes are correctly disposed of thereafter. In 2010, infected syringes and needles were accountable for 33800 new HIV infections, 1.7 million hepatitis B infections, and 315000 hepatitis C infections globally, according to the WHO.

Given the constant improvement of medical technology and the astonishing expansion in medical care in recent years, the creation of medical waste has increased significantly. Improper disposal of medical waste can threaten human health and damage the environment. The open-air storage of medical waste can result in the emission of a large number of toxic gasses such as methane and sulfide, which severely causes environmental pollution. Furthermore, viruses, heavy metals, and organic contaminants transported by untreated medical waste can cause significant contamination to surface and groundwater via runoff and infiltration. Heavy metals in landfill leachate reach the soil as a consequence of leaching and washing by rainfall, resulting in alterations in soil characteristics and heavy metal buildup, which eventually affects animal and plant life.

Technologies of Treatment and Disposal of Healthcare Waste:

The most common methods used to disinfect medical equipment are incineration, autoclaves, microwave technology, and UV light. These treatment and disposal practices are hazardous to the environment and public health. 

Incineration is a high-temperature, dry oxidation mechanism that converts organic and combustible waste to inorganic, incombustible substances, resulting in considerable waste volume and weight reduction.

Autoclaves have often been used to sterilize medical equipment for over a century, and they have recently been repurposed for the disposal of infectious waste. An autoclave is a metal vessel built to endure high pressures, with a sealed entrance and a network of pipes and valves that allow steam to enter and exit the vessel.

Microwave technology is a team-based approach in which treatment is accomplished by the activity of moist heat and steam produced by microwave energy. 

Germicidal ultraviolet (UV) light, an anti-infective technique that employs light wavelengths, has the ability to destroy bacteria and inactivate viruses. The sun naturally emits UV radiation, and most kinds are hazardous to living creatures as well as microbes. Studies have shown that UV radiation is efficient in reducing a variety of microorganisms, namely hospital-endemic strains such as Clostridium difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococci (VRE), as well as fungi and viruses such as Ebola virus, influenza, rhinovirus, enterovirus, and human metapneumovirus. UV-C, with a short wavelength of 250–280 nm, has the capacity to inactivate microorganisms given the significant absorption in their nucleic acids (Ramos et al., 2020). This frequently results in the development of cyclobutane pyrimidine dimers (CPD) in the nucleic acid sequences, which may cause errors in cell replication and, ultimately, cell death. Moreover, laboratory investigations have indicated that a range of UV light wavelengths in the 400-425 nm range may be employed for bacterial deactivation; nonetheless, 405 nm has been proven to have the best antibacterial action (Maclean et al., 2014). Exposure to this wavelength of light induces oxidative damage and microbial cell apoptosis. Hospitals currently utilize UV light technology to disinfect areas but the technique has not yet been widely used to disinfect medical equipment. 

Environmental impact analysis

According to the United Nations Environment Programme (UNEP) and the Institute for Global Environmental Strategies (IGES) report, incineration technology is harmful to the environment and public health as it involves the burning of healthcare waste which creates damaging gaseous pollutants such as steam and carbon dioxide. Furthermore, it generates possible carcinogenic polychlorinated biphenyls and dioxins and can produce fine particulates, as well as solid residues in the form of ashes, which are handled as toxic. Moreover, as per the UNEP and IGES report,  It is not possible to treat volatile and semivolatile organic substances, chemotherapeutic waste, mercury, and other hazardous chemical and radioactive waste that pollute the environment using autoclaves or microwave technology.  Furthermore, odors might be an issue in the vicinity of autoclaves if there is inadequate ventilation. And improperly separated waste can release some quantities of alcohols, phenols, formaldehyde, and other organic chemicals into the environment which is harmful to humans, animals, and plants. Also, treated waste using microwave technology keeps its physical shape, implying that more waste treatment for final disposal is necessary as per the UNEP and IGES report.

In contrast, the sun produces UV radiation naturally, which implies that ultraviolet is nature’s way of purifying, and so no hazardous by-products are formed when utilized to disinfect medical equipment. Thus, when evaluating the environmental effect of disinfection methods, UV light seems to be less harmful to the environment than incineration, autoclaves, and microwave technologies.

Conclusion

The insights highlighted in this article are remarkable in that they show the unsustainability of currently used disinfection techniques like incineration, autoclaves, and microwave technology. Thus, the article suggests that UV light is an environmental-friendly alternative to disinfecting medical equipment, potentially replacing the ecologically hazardous approaches that are currently in use and limiting the hazard of medical waste.

References

Maclean, M., McKenzie, K., Anderson, J. G., Gettinby, G., & MacGregor, S. J. (2014). 405 nm light technology for the inactivation of pathogens and its potential role for environmental disinfection and infection control. Journal of Hospital Infection, 88(1), 1-11.

Ramos, C. C. R., Roque, J. L. A., Sarmiento, D. B., Suarez, L. E. G., Sunio, J. T. P., Tabungar, K. I. B., … & Hilario, A. L. (2020). Use of ultraviolet-C in environmental sterilization in hospitals: A systematic review on efficacy and safety. International Journal of Health Sciences, 14(6), 52.

United Nations Environment Program and Institute For Global Environmental Strategies, Waste Management during the COVID-19 Pandemic:  From Response to Recovery, 2020, available at https://reliefweb.int/sites/reliefweb.int/files/resources/WMC-19.pdf.