Journal of Pharmaceutical Chemistry & Chemical Science

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Research Article - Journal of Pharmaceutical Chemistry & Chemical Science (2022) Volume 6, Issue 3

Hazardous and toxic medical wastes-treatment and control.

Great Iruoghene Edo1*, Favour Ogheneoruese Onoharigho2, Evidence Akhayere3

1Department of Chemistry, Cyprus International University, Nicosia, Cyprus

2Department of Chemistry, Elizade University, Ondo, Nigeria

3Department of Environmental Research Centre, Cyprus International University, Nicosia, Cyprus

Corresponding Author:
Great Iruoghene Edo
Department of Chemistry
Cyprus International University
Nicosia, Cyprus
E-mail
: greatiruo@gmail.com

Received: 16-Mar-2022, Manuscript No. AAPCCS-22-57624; Editor assigned: 19-Mar-2022, PreQC No. AAPCCS-22-57624(PQ); Reviewed: 01-Apr-2022, QC No. AAPCCS-22-57624; Revised: 31-May-2022, Manuscript No. AAPCCS-22-57624(R); Published: 07-Jun-2022, DOI:10.35841/aapccs-6.3.115

Citation: Edo GI, Onoharigho FO, Akhayere E. Hazardous and toxic medical wastes-treatment and control. J Pharm Chem Chem. 2022;6(3):115

Keywords

Medical waste, Health, Waste management, Public.

Introduction

According to section three of the Medical Waste Pursuit Act of 1988 “Any solid waste generated in the identification, treatment, or protection of citizens or animals, in analysis relevant to it, or within the manufacturing or testing of biologicals” [1].

It refers to any trash generated by the health-care industry, such as hospitals and medical laboratories. Anatomical waste, pathological waste, infectious waste, pharmaceutical waste, and alternative trash are all included in this category. Because of the new AIDS (Acquired Immune Deficiency Syndrome) crisis faced by alternative infectious diseases such as viral hepatitis, the general population is becoming increasingly concerned about medical waste disposal [2].

Medical wastes are a unit waste arising from identification, observation and preventive, curative or palliative activities in field of the veterinary and human drugs [3].

Approximately eighty fifth of the garbage generated by health-care providers is comparable to household waste and is referred to as "non-hazardous" or "generic health-care waste". It is mostly derived from the body, room, and work functions of health-care facilities, and will also include packaging trash as well as waste generated during the construction and maintenance of health-care facilities. The other 15% of health-care waste is considered "hazardous," posing a number of health and environmental dangers.

Poor medical waste management exposes health-care workers, waste handlers, and the general public to infections, toxic effects, and injuries. There's also a risk of transmitting drug-resistant microbes from health-care institutions into the environment due to poor health care waste management [4].

A joint WHO/UNICEF evaluation from 2015 indicated that only about 0.5% (58%) of the facilities sampled from twentyfour countries had suitable processes in place for the safe disposal of medical waste [5].

Sharps, particularly needles, are widely regarded as the most hazardous type of medical waste for health-care workers and the general public, owing to the risk of needle-stick injuries with a high risk of infection [2]. After a needle-stick injury with a needle from an infected supply patient, the risk of infection is 0.3% for HIV, third-dimensional for hepatitis C, and 6-30% for viral hepatitis [6].

Safe medical waste management is essential for providing high-quality, person-centered care, ensuring patient and worker safety, and protecting the environment. Therefore, this study aimed to predict the health care waste treatments and effect on the environment and public health Table 1.

Waste Categories Descriptions and examples
Hazardous medical wastes  
Infectious wastes These are wastes probable of containing pathogens and pose a risk of transfer of diseases. Examples of such are waste materials Highly contagious trash, such as cultures from the hospital, polluted with biological fluids such as blood.
Sharps Waste These are used or unused sharps, e.g. hypodermic, intravenous, or other needles.
Pharmaceutical, cytotoxic wastes Expired or no longer required pharmaceuticals; genotoxic chemicals; cytotoxic waste comprising compounds having genotoxic qualities, such as trash containing cytostatic medicine (frequently used in cancer treatment).
Pathological waste unused biological products; tissues within the body, organs, or fluids; bodily parts; foetuses
Radioactive waste Waste containing hot materials, such as unused liquid from irradiation or scientific research; tainted glasswork, packaging, or absorbent paper; and pee and waste material from treated patients or examined ones with unsealed radionuclides are examples.
Chemical waste Chemical compounds, such as laboratory reagents, film developer, disinfectants that have expired or are no longer needed, solvents, and trash containing high levels of heavy metals, are found in these wastes.
Waste from non-hazardous or regular health care Waste that poses no particular biological, chemical, thermal, or physical risk.

Table 1. Waste categories (hazardous and non-hazardous) with example.

Methods

This research is based on a survey of publicly available information on medical waste, including its nature, dangers, and various management approaches used or recommended in a variety of nations. The data was gathered through a literature study, an online search, and a conversation with project colleague.

Risks associated with medical wastes

One or more of the following qualities contribute to the dangers connected with medical waste:

• existence of infectious agents

• a genotoxic or cytotoxic chemical composition

• presence of hazardous or venturous substances, or medications that are biologically hostile

• Availability of radiation

• used sharps in the vicinity

Individuals who work in close proximity to hazardous medical wastes, as well as those who work in health-care facilities, are at risk of being exposed to a hazard. People who work for UN agencies generate hazardous waste, and those who work for UN agencies either handle it or are exposed to it as a result of negligent acts. The following are the most vulnerable groups.

• medical doctors, nurses, auxiliary health-care workers, and hospital maintenance workers

• people in hospitals or those receiving home care

• visitors to hospitals and clinics

• cleaners, those of us who add laundries, porters, and others in support services

• personnel transporting waste to a treatment or disposal facility

• employees working in waste-management facilities (such as landfills or treatment plants), as well as informal recyclers (scavengers)

When hazardous health-care waste is abandoned or illegally disposed of, the general public may be put in danger.

Some infections which can be caused by exposure to medical wastes are listed in Table 2. The trash that poses the greatest health danger is pathogen-targeted cultures and contaminated sharps (especially hypodermic needles).

Infection Causative Organisms Mode of Transmission
Skin infections Streptococcus spp. Pus
Ocular infection Herpesvirus Eye secretions
Haemorrhagic fevers Junín, Lassa, Ebola, and Marburg viruses All bloody products and secretions
Respiratory infections Mycobacterium tuberculosis, measles virus, Streptococcus pneumoniae, severe acute respiratory syndrome (SARS) Inhaled secretions, saliva
Anthrax Bacillus anthracis Skin secretions
Septicaemia Staphylococcus spp. Blood
Viral hepatitis A Hepatitis A virus Faeces
Viral hepatitis B and C Hepatitis B and C viruses Blood and body fluids
Meningitis Neisseria meningitidis Cerebrospinal fluid
Genital infections Neisseria gonorrhoeae, herpesvirus Genital secretions
Candidaemia Candida albicans Blood
Acquired immunodeficiency syndrome (AIDS) Human immunodeficiency virus (HIV) Blood, sexual secretions, body f luids
Gastroenteric infections Enterobacteria, e.g.  Salmonella, Shigella  spp,  Vibrio cholerae, Clostridium difficile, helminths Faeces and/or vomit
Avian influenza H5N1 virus Blood, faeces
Bacteraemia Coagulase-negative Staphylococcus  spp. (including methicillian-resistant  S. aureus), EnterobacterEnterococcus, Klebsiella  and  Streptococcus  spp. Nasal secretion, skin contact

Table 2. Infections caused by contact with medical waste, including the organisms that cause them and how they disseminate.

In theory, any needle-stick injury will result in the transmitting blood borne infections; however, there is evidence that hollow needles, such as suture needles, are associated with a higher risk of transmission than solid needles [7]. It is undeniable that plasmids from laboratory strains found in medical waste were transferred to autochthone microorganisms through the waste disposal system [2]. Furthermore, associate antibiotic-resistant Escherichia coli are shown to survive in an activated sludge plant, but there does not appear to be vital transfer of this organism under traditional waste disposal and treatment conditions [8].

Experimental studies have shown that a lot of antineoplastic medicine area unit cancer and mutagenic; secondary pathologic process (occurring when the first cancer has been eradicated) is understood to be related to some kinds of therapy. Several cytotoxic medications are extremely irritants and have harmful native effects when they come into contact with the skin or eyes. Cytotoxic medications may also cause dizziness, nausea, headache, or eczema. Any release of genotoxic waste into the environment may have unfavorable environmental consequences. Chemical wastes can cause intoxication through acute or chronic exposure, as well as physical injuries, the most common of which are chemical burns. Intoxication can occur as a result of chemical or pharmaceutical absorption through the skin or secretion membranes, as well as inhalation or ingestion. Contact with ignitable, corrosive, or reactive chemicals can cause injuries to the skin, eyes, or secretion membranes of the airways (e.g. methanal and different volatile substances).

The type and extent of radioactive material exposure determines the nature of the illness. It can range from a headache, lightheadedness, and a physiological response to a variety of other serious issues. Hot waste is genotoxic, and a high enough radiation dose may also have an effect on genetic material.

Results

Treatment and management of medical wastes begin with the segregation and assortment observes when that wastes area unit been treated by numerous techniques and disposed of victimization accessible disposal choices.

Segregation and assortment of medical wastes

The appropriate segregation of health-care waste is the duty of the individual who generates each waste item, regardless of their position within the organization. Medical waste collection is completed as close to the point of generation as possible, which implies that segregation should occur in a medical space, at a side, in a surgery or laboratory by nurses, physicians, and technicians. At the point of generation, the best and safest waste segregation system is to separate all dangerous waste from non-hazardous general waste (which is usually in larger quantities). To ensure the safety of employees and patients, hazardous waste is divided into two categories: used sharps and potentially infectious items. As a result, the "three-bin system" requires the segregation of general nonhazardous waste, possibly infectious waste, and used sharps into separate containers. A World Health Organization (WHO) theme is accessible for segregation and assortment of medical waste as seen in Table 3.

Waste type Container colour and marking Container type Frequency of collection
Sharps Yellow with a’ sharp’ marking and a biohazard emblem. Perforated When the line is reached or the container is three-quarters full.
Infectious If contains extremely hazardous wastes, yellow with biohazard emblem and added indication of 'very infectious.' In a container, insert a leak-proof, sturdy plastic bag (bags for highly infectious waste should be capable of being autoclaved). When the container is three-quarters full, or at least once a day.
Chemical and pharmaceutical Brown, with the relevant hazard symbol on it. Corrugated container or plastic bag On demand.
Pathological Yellow with biohazard symbol. A robust, leak-proof plastic bag is placed in a container. At least once a day, or when the container is three-quarters filled.
Radioactive waste Labelled with radiation symbol Lead box On the spot.
General health-care or non - hazardous wastes Black After usage, a plastic bag is placed into a container or container that has been sterilized. Once a day, or whenever the container is three-quarters full.

Table 3. Segregation and Collection scheme recommended by WHO.

Treatment technologies and management of medical wastes

According to the Municipal Convention, it is imperative that waste treatment methods that reduce the formation and release of chemicals or hazardous emissions be made a priority. Overall, chemical, pharmaceutical, and material waste must be included in the national hazardous waste strategy and treated in accordance with international and national regulations. In general, steam (for example, autoclaving) or other non-burn technology should ideally be used to remove infectious and sharp waste in the treatment of infectious waste [9]. The choice of treatment technique is based on local conditions and includes consideration of available resources as well as professional experience, important national rules and needs, waste components and volume, technical desires for implementation, functionality, and servicing of the treatment unit, safety and environmental factors, and value concerns. Various treatment techniques/technologies applied among the management of medical wastes are classified into;

Incineration

Steam primarily based technologies: Other treatment techniques that embrace biological and chemical and mechanical techniques [10].

Incineration

Incineration is a dry natural action method that converts organic and flammable rubbish to inorganic, fire-resistant material at high temperatures (850 °C to 1100 °C), resulting in a significant reduction in waste volume and weight. It is employed in the treatment of hazardous materials. “If medical waste is incinerated in conditions that do not represent best available techniques or ideal environmental procedures, there is the great possibility for the release of PCDD [polychlorinated dibenzodioxins] and PCDF [polychlorinated dibenzofurans] in comparatively high concentrations," according to the capital Convention guidance on best available techniques and best environmental practices [11]. Minor health-care incinerators were investigated by the World Health Organization (WHO), which discovered "severe challenges with the placement, performance, maintenance, and monitoring of [these] incinerators" that had to be addressed [11]. Due to these and other issues, as well as the extremely exorbitant costs for current combustion to meet Best Available Technique (BAT) criteria, the world organization agency report all over that "small-scale combustion is seen as a transmutation indicates that of disposal for health-care waste" [1]. Steam primarily based technologies include: Autoclaving and Microwave treatment.

Autoclaving

Autoclaving is the most frequent type of steam treatment, and it involves using saturated steam to clear waste. Potentially contaminated air is thoroughly filtered (e.g. using a High- Efficiency Particle Air (HEPA) filter) as it exits the autoclave. Temperatures in autoclaves range from 121°C to 134 °C. Autoclaves have been used to disinfect medical devices for over a century, and they've also been employed to handle harmful trash for many years.

Microwave

Microwave radiation is used to heat the water contained inside the trash using microwave technology. Some microwavebased devices use transformation processes such as tearing or combining. A HEPA filter is used in a typical semicontinuous circuit to prevent the spread of mobile diseases. Waste is processed using a tool, and the waste particles are then pushed via a degree auger (conveyor screw), where they are subjected to steam and the temperature is increased to 100 °C using microwave generators. Cultures and stocks, sharp objects, items stained with blood and bodily fluids, isolation and surgical waste, laboratory garbage (excluding chemical waste), and soft waste (e.g. gauze, bandages, robes, and bedding) from patient care are examples of waste processed in microwave systems. One microwave device has indeed been satisfactorily proven with livestock waste and may be used to treat pathological waste such as tissues in the future [12]. Flammable and semi volatile organic compounds, chemotherapeutic waste, mercury, and other dangerous chemical waste should not be handled in a passing microwave.

Other Techniques

Mechanical

Ripping up, crushing, mixing, and compressing are mechanical methods for reducing trash volume, however they do not eradicate germs. Shredders and mixers can speed up heat transmission while also exposing a large amount of trash for treatment. Mechanical methods should not be used to eliminate contagious or sharp trash before disinfection, unless the mechanical approach is part of an isolated circuit that sterilizes air before it is released into the surrounding atmosphere.

Chemical

Disinfectants are commonly used in completely automated chemical methods of treatment. These are troublesome because they end up as cytotoxic pollutants, increasing the risk of toxins being exposed to medical waste workers. Chemical treatment, which is already widely employed in medical centers to eliminate or inactivate germs on medical instruments, floors, and walls, is now being used towards the treatment of clinical waste. Rather than sterilization, this procedure usually leads to treatment. Chemical treatment is ideal for dealing with liquid waste such as blood, urine, feces, and hospital waste. Along with microbial cultures and sharps, solid, even highly harmful, health-care wastes might be chemically cleaned, with the following condition:

Prior to treatment, garbage must generally be shredded or fringed. The device might be a liability in the treatment process since it is susceptible to mechanical error or malfunction.

Strong disinfectants are necessary, which may be hazardous and should only be used by individuals who have been properly educated and are appropriately protected. The effectiveness of disinfection is determined by the functional circumstances within the treatment potentiality. Only the exterior of undamaged solid waste items gets disinfected.

Biological

These mechanisms are inherent in all living things, but they are notably related to the decomposition of organic materials in medical waste management. Enzymes are used in some biological treatment processes to speed up the decomposition of pathogen-containing organic waste. Decomposition and vermiculture (the breakdown of organic wastes by worms) are biological methods that have been successfully employed to degrade medical trash, as well as other organic digestible waste including placenta waste. Another biological option is the spontaneous breakdown of pathological waste by burial [13].

Disposal choices for medical wastes

Sharp waste disposal: Sharp waste is decontaminated and disposed of in protected sharp dumps on the site of the healthcare institution or encased with an immobilization medium such as cement before disposal. These techniques are only recommended in situations when garbage is carried out manually and there is no secure site for general waste.

Pathological waste disposal: In low-resource environments, placenta pits are an efficient way to dispose of pathological waste. They would want to be placed at precise locations to minimize groundwater pollution, and they would want to be quick and secure. Normal decomposition and absorption of fluids into the soil considerably minimizes the amount of trash in the pit and aids pathogen inactivation. When no other treatment options are available, pathological waste might be disposed of in lowland.

General / non-hazardous waste: When conventional nontoxic waste cannot be disposed of at a public disposal site and space is available, an interim disposal site within the buildings of the health-care institution might be developed, which would be sealed to prevent unwanted entry and keep people and animals out. The garbage should be disposed of and a layer of dirt applied every day. Some caring facilities may not have a public dumping location or enough space for dumping on the grounds. Unauthorized entrance to the realm should be prevented, for example, by erecting a barrier. These options should be viewed as short-term stopgap measures till a more secure and ecologically friendly option is developed [14].

Discussion

The first was a study of medical waste done by the Washington Department of Ecology in which it was claimed that eightyfive% of Washington hospitals isolated infectious trash from medical waste. According to a second assessment of 95 hospitals throughout the country, 95.4% of hospitals quarantined infectious trash. Clinical hospitals, maternity hospitals, and general hospitals produce the largest amounts of medical waste, according to UN agency data, whereas pharmacy and elderly hospital departments produce lesser amounts [15]. The data corresponds to numbers made in the 1980s; nonetheless, the pattern is still present. Despite the fact that geriatric units produce the least quantity of medical trash, the garbage contains diapers and should be handled as infectious waste. The majority of the time, though, it is thrown away alongside other community garbage [16].

In the United States, the estimated death rate as a result of acute exposure and infections among health-care workers is 17-57 cases per million workers [17]. Among attention staff, nurse’s square measure the foremost exposed population. However, estimating the specific spectrum of illness and injury associated with medical waste processing is extremely difficult. Conversely, data from a European country about activity illnesses among health-care workers imply a poor level of cleanliness and waste-handling instruction [18,19]. Nurses and housekeepers UN agencies that handle infected needles and other sharp items are particularly vulnerable to blood-borne infectious illnesses such as serum hepatitis B and C, and HIV, as well as gastroenterological, metabolic, and skin disease [6]. According to data from the United States, fifty-seven HIV infections in medical workers were reported in 2001, all of which were caused by sharp object injuries or transmissions through the skin and mucous membranes [20]. According to Japanese data, the risk of HIV infection after a needle injury is nil. 3%, three-dimensional serum hepatitis 3-5%, and viral hepatitis 3-5% [21].

Medical wastes are thought to be capable of causing illness and disease in humans, either directly or indirectly through pollution of soil, groundwater, surface water, and air. The wind-blown dusts from these landfills may include germs and harmful substances [22].

Recommendations

The following are some suggestions for further research:

• To achieve a clear conclusion, additional information on the implications, disposal, and management approaches of medical wastes should be acquired.

• Statistics and references should be from industrialized nations or countries with a well-functioning medical waste management system.

• A thorough investigation of this medical waste and its treatment is required.

Conclusion

Medical waste is shown to pose a serious hazard to human health and, as a result, the environment. Appropriate management of medical waste is essential for providing highquality, person-centered care, ensuring the safety of patients and workers, and conserving the environment. Medical waste management is being self-addressed at the global scale through the WHO and UN agency Water, Sanitation, and Hygiene (WASH) in health care facilities: global action strategy (WHO & UN agency, 2015). A diversity of current public health programs and standards, including those on improving the quality of care for mothers, newborns, and children, the global learning laboratory on universal health insurance, core standards on infection intervention and management, and the global action arrange on injection safety and integration, have all included the safe management of health-care waste in their programs and activities.

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