Biomedical waste or hospital waste is any kind of waste containing infectious materials generated during the treatment of humans or animals as well as during research involving biologics done in the laboratory. Although medical waste makes up about 2-3% of the total amount of waste, this is one of the most hazardous waste. Infectious diseases patients undergo numerous medical procedures, including invasive ones like injections, surgery, and research, resulting in the production of disposable instruments and materials contaminated with biological fluids which is very hazardous to both human beings and the environment. These hazardous health care waste are categorized on the basis of the various compositions. Infectious waste includes contaminated blood, lab work, and infected patients. Pathological waste includes human tissues and organs. Sharps waste includes disposable tools. Chemical waste includes solvents, disinfectants, and heavy metals. Pharmaceutical waste includes expired drugs and vaccines.Cytotoxic waste includes genotoxic substances. Radioactive waste contains contaminated products. Non-hazardous waste includes metals, compounds that are not harmful to the environment.
Medical waste poses a high epidemiological risk due to its high concentration of dangerous microorganisms, toxic drugs, and radiological hazards. By-products can cause injuries, tetanus, and hepatitis B, release of antibiotics and cytotoxic drugs contributes to environmental pollution and through the release of toxic sewage and compounds like mercury or dioxins. WHO estimates that contaminated syringe injections cause 21 million HBV, 2 million C, and 260,000 HIV infections annually. In developing countries, waste handlers, known as miners, are at risk of needle pricks and exposure to toxic materials due to garbage rummage.
All these need to be properly maintained and disposed of which will reduce the threat to safety of human beings and other organisms. Some of the appropriate method for the management of health care waste are mentioned here:
1. Chemical disinfection is used to kill microorganisms on medical equipment, floors and walls and also to treat health care waste to kill or inactivate pathogens. This method is used for treating liquid waste such as blood, urine, stools, or hospital sewage. However, other waste can also be disinfected using chemical disinfection, before disposal. But anatomical parts, animal carcasses are usually not disinfected.
2. Autoclaving is an efficient wet thermal disinfection process which is done using an autoclave. Reusable medical equipment is sterilized by using this process. An autoclave is used to sterilize reusable medical equipment like surgical equipment, laboratory instruments, pharmaceutical items, and other materials. This method can be used to sterilize solids, liquids, hollows, and instruments of various shapes and sizes.
3. Encapsulation is a process in which cubic boxes made of high-density polyethylene or metallic drums, are filled with sharps and chemical or pharmaceutical wastes. Encapsulation is very effective in reducing the risk of scavengers or stray animals gaining access to the hazardous health-care waste. Encapsulation is not suitable for non-sharp infectious waste, but may be used in combination with burning of such waste.
4. Inertization is the process of mixing waste with cement and other substances before disposal suitable for mixing of toxic substances contained in the waste to surface water or groundwater. The typical proportions for the mixture is: 65% pharmaceutical waste, 15% lime, 15% cement and 5% water. Inertization however is expensive and not suitable for a wider variety of waste.
5. Land disposal involves the management of waste, with two types: open dumps and sanitary landfills. Open dumps spread waste, increasing health risks to human beings and other organisms. On the other hand, sanitary landfills prevent contamination, air pollution, and public contact, treating and managing waste daily.
6. Incineration is a controlled method of burning waste in high temperatures, producing gaseous emissions like steam, carbon dioxide, nitrogen oxides, and toxic substances. It is the oldest and most commonly used waste management method, but should not be used for pressurized gas containers, reactive chemical waste, radiographic waste, or high mercury or cadmium content.
Medical waste must be appropriately sorted and disposed of in order to lower the risks of human infection, the spread of illnesses, and the onset of epidemics. Even if medical waste is not regarded as particularly harmful, it must nevertheless be properly disposed of.