Dr Hidayathulla Shaikh

At the end of the lecture students should be able to – Mention categories of health care wastes. Discuss Handling, Storage and Transportation of Health care wastes. Explain different types of treatment of Health care wastes.

Health care waste is defined as “all the waste generated by health care establishments, research facilities and laboratories”. It also includes waste produced in the course of health care undertaken in home. Waste produced by the health care activities carry a higher potential for infection and injury than any other types of waste.

Inappropriate and inadequate handling of health care waste may have serious public health consequences and a significant impact on environment. Wherever it is generated, safe and reliable methods for its handling are therefore essential.

TypeExample 1 Infectious wastesLab cultures, equipments 2 Pathological wastesBody parts, blood 3 SharpsNeedles, blades 4 Pharmaceutical wasteExpired drugs 5 Genotoxic wasteCytotoxic drugs 6 Chemical wastesLab reagents, solvents, disinfectants 7 Wastes with high content of heavy metals Mercury 8 Pressurized containersGas cylinders, aerosol cans 9 Radio active wasteUnused liquid from radio therapy, contaminated glassware

Handling, Storage and Transportation of Health care wastes The effective management of health care waste is done by segregation and identification of the waste. The most appropriate way of identifying the categories of health care waste is by sorting the waste into color coded plastic bags or containers.

Collection The waste bags should be tightly closed or sealed when they are three quarter full. Waste should not be allowed to accumulate at the point of production. Waste should be collected daily and transported to storage site. Storage The waste should be stored in separate area, room or building. The storage area should be such that it can be cleaned and disinfected. It should have good lighting and ventilation and should be located away from the food sources.

Transportation Wastes should be transported by means of wheeled trolleys, containers, carts or vehicles which are not used for any other purposes. Vehicles should be such that the wastes should be loaded an unloaded easily. Vehicles should not have sharp edges that can damage the waste bags. The vehicles should be cleaned and disinfected daily.

1) Incineration 2) Chemical disinfection 3) Wet and Dry thermal treatment 4) Microwave irradiation 5) Encapsulation 6) Land disposal 7) Inertization

It is a high temperature dry oxidation process, that reduces organic and combustible waste to inorganic incombustible matter and results in a very significant reduction of waste volume weight. This process is used to treat waste that can not be recycled, reused or disposed off in a landfill site. Types of incinerators 1) Double chamber pyrolytic incinerator 2) Single chamber furnaces 3) Rotary kilns

In this method, chemicals are added to waste to kill or inactivate the pathogens. This method is most suitable for treating liquid waste such as blood, urine, stools or hospital sewage. The disinfectants usually used are a) Formaldehyde b) Ethylene oxide c) Glutaraldehyde d) Sodium hypochlorite e) Chlorine dioxide.

It is based on exposure of shredded infectious waste to high temperature, high pressure steam, & similar to the autoclave sterilization process. The process requires the waste be shredded (broken into small pieces) before treatment to increase disinfection efficiency. This process is inappropriate for the treatment of anatomical and animal waste.

Most microorganisms are destroyed by the action of Microwave of frequency about 2450MHz and a wavelength of cm. The water contained within the wastes is rapidly heated by the microwaves and the infectious components are destroyed by heat conduction.

This procedure involves filling containers made of high density polyethylene or metal drums with wastes. These containers are then filled with a medium of immobilizing material such as plastic foam, cement or clay. After the medium has dried, the container is sealed and disposed off in the landfill sites.

Safe burial of waste may be used when this is the only option available, however certain basic rules should be followed.. a) Access to the disposal site to be restricted to authorized personnel only. b) Only hazardous health care waste should be buried. c) Large quantity of chemical waste should not be buried at one time to avoid environmental pollution.

This process involves mixing waste with cement & other substances before disposal to minimize the risk of toxic substances contained in the wastes migrating into the surface or ground water. 65% pharmaceutical waste, 15% lime, 15% cement & 5% water is added in the procedure. It is suitable for pharmaceuticals and incineration ash with a heavy metal content.

WHO in 2000 said - contaminated injections with contaminated syringes caused: 21 million Hepatitis B virus (HBV) infections (32% new infections). 2 million Hepatitis C virus (HCV) infections (40% new infections). 2,60,000 HIV infections (5% new infections). Epidemiological studies says person who experiences one needle stick injury – has a risks of 30%, 1.8%, and 0.3% respectively of becoming infected with HBV, HCV and HIV.

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