In this article we will be talking about Biomedical Waste Management (Medical Waste and its Management).
First of all;
What are Biomedical Waste
Biomedical waste is any waste that is generated as a by-product of healthcare work at doctor’s surgeries, dentists, hospitals and laboratories. It includes any material that could come into contact with the body during diagnosis, research, drug administration or any type of treatment.
It’s likely to be infectious, or potentially infectious, and is often contaminated with bodily fluids in some way – but the term can also be used to refer to general waste from any medical practice, as well as specific waste streams typically found in the medical industry.
Before we go forward lets talk briefly about Waste Management, the umbrella where Biomedical Waste Management falls under.
What is Waste Management
In simplest terms, Waste management includes the activities and actions required to manage waste from its inception to its final disposal.
This includes the collection, transport, treatment and disposal of waste, together with monitoring and regulation of the waste management process.
Waste can be solid, liquid, or gas and each type has different methods of disposal and management. Waste management deals with all types of waste, including industrial, biological and household. In some cases, waste can pose a threat to human health. Health issues are associated throughout the entire process of waste management. Health issues can also arise indirectly or directly. Directly, through the handling of said waste, and indirectly through the consumption of water, soil and food. Waste is produced by human activity, for example, the extraction and processing of raw materials. Waste management is intended to reduce adverse effects of waste on human health, the environment or aesthetics.
Waste management practices are not uniform among countries (developed and developing nations); regions (urban and rural areas), and residential and industrial sectors can all take different approaches.
Hierarchy of Waste Management
The waste hierarchy refers to the “3 Rs” Reduce, Reuse and Recycle, which classifies waste management strategies according to their desirability in terms of waste minimization. The waste hierarchy is the cornerstone of most waste minimization strategies. The aim of the waste hierarchy is to extract the maximum practical benefits from products and to generate the minimum amount of end waste; see: resource recovery. The waste hierarchy is represented as a pyramid because the basic premise is that policies should promote measures to prevent the generation of waste. The next step or preferred action is to seek alternative uses for the waste that has been generated i.e. by re-use. The next is recycling which includes composting. Following this step is material recovery and waste-to-energy. The final action is disposal, in landfills or through incineration without energy recovery. This last step is the final resort for waste which has not been prevented, diverted or recovered. The waste hierarchy represents the progression of a product or material through the sequential stages of the pyramid of waste management. The hierarchy represents the latter parts of the life-cycle for each product.
Importance of Biomedical Waste Management
According to the position statement by the United Nations’ World Health Organization (WHO), in 2000 the improper Biomedical Waste Management (primarily the use of infected hypodermic needles and syringes) caused the following infections worldwide:
- Hepatitis B: 21 million infections;
- Hepatitis C: 2 million infections; and
- HIV: 260,000 infections.
The above figures show how relevant appropriate medical waste treatment is. According to the WHO directive, hazardous waste should be processed as near to its place of generation as possible. The risks involved in the transportation of hazardous waste are large and the risk factor found in some materials (e.g. those that are infectious) increases daily. Suitably located and equipped waste disposal facilities can minimize the need to transport hazardous materials. (WHO publication, 2004)
A lot of the waste from hospitals is infectious biological material or objects, which although they are considered “communal” waste, are in fact contaminated. These latter items include textiles, bandages, syringes, and other objects exposed to infection through contact with patients.
Very much of the waste from hospitals is made up of special surgical instruments, such as surgical implants and other implements employed during operations.
Major Sources of Biomedical Waste
The major sources of health-care waste are:
- Hospitals and other health facilities
- Laboratories and research centres
- Mortuary and autopsy centres
- Animal research and testing laboratories
- Blood banks and collection services
- Nursing homes for the elderly
High-income countries generate on average up to 0.5 kg of hazardous waste per hospital bed per day; while low-income countries generate on average 0.2 kg. However, health-care waste is often not separated into hazardous or non-hazardous wastes in low-income countries making the real quantity of hazardous waste much higher.
Types of Biomedical Waste
There are ten defined categories as follows
- Human anatomical waste: (tissues, organs, body parts)
- Animal waste: (including animals used in research and waste originating from veterinary hospitals and animal houses)
- Microbiological and biotechnology waste: (including waste from lab cultures, stocks or specimens of microorganisms, live or attenuated vaccines, wastes from production of biologicals, etc.
- Waste sharps: (used/unused needles, syringes, lancets, scalpels, blades, glass etc.)
- Discarded medicines and cytotoxic drugs.
- Soiled wastes: (items contaminated with blood and body fluids, including cotton dressings, linen, plaster casts, bedding etc.)
- Solid wastes: (wastes generated from disposable items other than waste sharps such as tubing, catheters, i.v. sets, etc.)
- Liquid waste: (waste generated from washing, cleaning, house keeping and disinfection activities including these activities in labs).
- Incineration ash: (from incineration of any biomedical waste)
- Chemical waste: (chemicals used in production of biologicals and disinfection)
Hazards of Biomedical Waste
Health-care waste contains potentially harmful microorganisms that can infect hospital patients, health workers and the general public. Other potential hazards may include drug-resistant microorganisms which spread from health facilities into the environment.
Adverse health outcomes associated with health care waste and by-products also include:
- Sharps-inflicted injuries;
- Toxic exposure to pharmaceutical products, in particular, antibiotics and cytotoxic drugs released into the surrounding environment, and to substances such as mercury or dioxins, during the handling or incineration of health care wastes;
- Chemical burns arising in the context of disinfection, sterilization or waste treatment activities;
- Air pollution arising as a result of the release of particulate matter during medical waste incineration;
- Thermal injuries occurring in conjunction with open burning and the operation of medical waste incinerators; and
- Radiation burns.
Principles of Biomedical Waste Management
The principles of biomedical waste management are as follows:-
General principles of hygiene and sanitation
Observance of general principles of hygiene and sanitation such as cleanliness, good house keeping, adequate supply of safe water, sanitary facilities and proper ventilation are essential components of a good bio-medical waste management plan.
Waste minimization: It is essential that every waste generated from the hospital should be identified and quantified. Hospitals should endeavour to reduce waste by controlling inventory, wastage of consumable items and breakages etc. Waste can also be minimized by recycling certain waste such as glassware, plastic material etc after proper cleaning and disinfection.
Waste segregation: Segregation of waste at source and safe storage is the key to whole hospital waste management process. Segregation of various types of wastes into different categories according to their treatment/disposal options should be done at the point of generation in colour coded plastic bags/containers as per schedule II of the gazette notification. The needles and syringes should be disinfected and mutilated before segregation.
- Waste treatment on site: Microbiological and biotechnology waste being highly infectious should be treated on site by autoclaving/microwaving/chemical treatment.
- Waste transportation: The waste should be transported to kerb collection area in covered container. All containers should have biohazard label according to schedule III of the gazette notification. If a container is transported from the premises where biomedical waste is generated to any waste treatment facility outside the premises, the container shall, apart from the label prescribed in schedule III also carry information prescribed in schedule IV. The containers and the vehicles used for transportation of biomedical waste should not be used for any other purpose. Care should be taken to avoid spills.
Waste treatment off site.
The various final treatment options available are:-
v. Plasma torch technology
vi. Medical waste sterilization unit
All the above systems have certain limitations. Heavy metals and plastic cannot be burnt in incinerators. Microwave cannot take up large pieces of metals and body parts for disinfection. The autoclave does not reduce the volume and may increase the weight of the waste due to moisture. Plasma Torch Technology is prohibitively expensive. Hydroclaves are comparatively cheap to run but not suitable for large body parts. Hence one has to look for multiple options instead of basing the waste treatment system only on one option.
Read Also: 5 Major ways of hazardous waste disposal
Types of Biomedical Waste Disposal
Waste disposal is particularly important when it comes to medical supplies, because some waste can be contaminated with diseases or dangerous pathogens. All biomedical waste is not disposed in the same way, and different disposal companies follow different methods.
The process of autoclaving involves steam sterilization. Instead of incineration, which can be expensive, autoclaving simply introduces very hot steam for a determined amount of time. At the end of the process, microorganisms have been completely destroyed. This process is particularly effective because it costs much less than other methods, and doesn’t present any personal health risks. While some biomedical waste isn’t able to be disposed of via autoclaving, around 90% of materials are sanitized this way before being sent on to a landfill.
The major benefits of incineration are that it is quick, easy, and simple. It effectively removes the waste entirely, and safely removes any microorganisms. However, when burning hazardous materials, emissions can be particularly dangerous. Some states prefer for waste disposal companies to look towards incineration as their first choice, but materials must be reviewed and determined as safe to burn.
When it comes to liquid waste, a common biomedical waste disposal method can be chemical disinfection. Chlorine is a regular choice for this process, and is introduced to the liquid waste in order to kill microorganisms and pathogens. Chemical disposal can also be used for solid wastes, but it is recommended that they be grinded first to ensure maximum decontamination. Liquid waste, once decontaminated, is then disposed into the sewer system.
During this process, waste is shredded, mixed with water, and then internally heated to kill microorganisms and other harmful elements. One of the main benefits of this process is the shredding aspect; it lowers the volume of biomedical waste, and it is reportedly more energy efficient to use this method than to incinerate. While it can’t be used for all biomedical wastes, it can be utilized for a good 90% of it, just like autoclaving.