Hospital Waste Management:
i) Health Hazards of heath care waste
ii) Types of hazards
iii) Ways to treat and dispose of healthcare waste
iv) Bio-medical waste management in India (Schedule I, II, III)
2. Hazards of HC waste
Characteristics:
• Contains infectious agents
• Contains toxic or hazardous chemicals/pharmaceuticals
• Contains sharps
• Radio-active
At risk people:
• HC workers: doctors, nurses, auxiliaries, maintenance
• Patients and visitors to health centres
• Workers in support services (laundry, waste handling)
• Workers in waste disposal facilities (landfills, incinerators)
3. Different Hazards
Infectious waste/sharps
• Pathogens may enter body through puncture/cut in skin/MM; inhalation or
ingestion
• Particularly Hep B/C
• Bacteria may also be resistant to antibiotics and chemical disinfectants
Chemical/pharmaceutical waste
• Toxic, genotoxic, corrosive, flammable, reactive etc
• Acute or chronic exposure
Genotoxic Waste
• Severity dependant on substance toxicity and extent/duration of exposure
• Cytotoxic drugs/chemicals/wastes
Radioactive waste
• Determined by type and extent of exposure
• Headache, dizzy, vomit and other serious problems
• Genotoxic, so can affect genetic material
4. Treatment/disposal techniques
1) Incineration
• High temp dry oxidation process which reduces organic and
combustible waste to inorganic and incombustible matter
significant reduction of waste volume and weight
• Requires no pre-treatment
• Waste that are suitable: i) low heating volume
ii) combustible matter content >60%
iii) non-combustible solids content <5%
iv) non-combustible finds content <20%
v) moisture content <30%
• Waste types not incinerated: pressurized gas containers, reactive
chemical wastes, silver salts, photographic and radiographic wastes,
halogenated plastics (PVC), waste with high Hg or radium content
5. 2) Chemical disinfection
• Chemicals added to waste to kill/inactivate pathogens
• This normally results in disinfection and not sterilization
• Best for liquid wastes like urine, blood, stools or hospital sewage
3) Wet and dry thermal treatment
• WET: Steam disinfection is exposure of shredded infectious waste
to high temp + steam (similar to autoclave). Inappropriate for
anatomical wastes and chemical/pharmaceutical wastes
• DRY: Screw-feed technology (non-burn, dry thermal disinfection).
Shredded waste is heated in a rotating auger- this reduces volume
by 80% and weight by 25-30%. Suitable for sharps, infectious waste.
Not for pathological, cytotoxic or radioactive waste
6. 4) Microwave irradiation
• Most microbes destroyed by MW of frequency of about 2450 MHz
and wavelength 12.24 nm
• Water in waste rapidly heated by MWs and infectious components
destroyed by heat
5) Land disposal
• Landfills used if municipality or medical authority lacks means to
treat waste before disposal
• Two types: i) land-open ii) sanitary
• Open dumps pose risk of people/animals coming into contact with
infectious pathogens
• Advantages of sanitary: geological isolation from environment,
appropriate prep of site before waste disposal, staff present at site
to oversee, organized dumping
7. 6) Inertization
• Process of mixing waste with cement and other substances
before disposal in order to minimize the risk of toxic
substances contained in the wastes migrating into surface or
ground water
• E.g 65% pharmaceutical waste + 15% lime + 15% cement + 5%
water
• They are produced on site and then transported to the
storage sites
• Advantage: inexpensive
• Disadvantage: not applicable to infectious waste
