While first-world medical technology and cutting-edge therapies are rapidly adopted by the Indian healthcare sector, hospitals almost never display the same readiness to embrace the responsibility of safely disposing of the waste generated by these processes. However, the biomedical waste sector has been relentless in developing increasingly innovative solutions, which – coupled with progressively stringent government rules and regulations – are finally bringing about widespread adoption of responsible waste management in the healthcare segment.
About 10–25% of the bio-medical waste (BMW) is hazardous and presents physical, chemical, and/or microbiological risks to the general population and health-care workers associated with handling, treatment, and disposal of waste. An effective communication, awareness and education strategy can help reduce the biomedical waste problem in India, which faces the challenge of having to treat more than 4.2 lakh kg of biomedical waste per day. It is also necessary to increase the number of Common Biomedical Waste Treatment Facilities from just 150 nationwide, which is inadequate to treat present volumes of waste.
“Improper, non-validated and unsupervised recycling techniques have resulted in many disposables being sold and re-used in the black markets of many developing countries, contributing to the growing pandemic of infections.”
– Dr R Sukanya
Why does India lag behind?
The challenges pertaining to medical waste disposal in developing countries stem largely from lack of funding and laxity of regulations. The sight of vast open areas where the segregated biomedical waste is finally disposed of is the rule rather than the exception, leading to an increase in the number of blood-borne and communicable diseases like Hepatitis B, HIV and Hepatitis C among biomedical waste handlers. Needles used in hospitals need very careful handling, as the statistic of 4 needlestick accidents per 100 beds is a cause of concern in Asian countries, especially in India. Improper, non-validated and unsupervised recycling techniques have resulted in many disposables being sold and re-used in the black markets of many developing countries, contributing to the growing pandemic of infections. To add to this mayhem is the grave environmental and ecological damage caused by conventional disposal techniques used in biomedical waste treatment.
New processes, new rules
In India, the Ministry of Environment, Forest and Climate Change has amended the BMWM rules in 2016 to increase their coverage, simplify categorization and authorization, and improve segregation, transport and disposal methods to decrease environmental pollution. The role of incinerators in increasing environmental air pollution has been checked by issuing new standards for incinerators and improving their operations. The Central Pollution Control Board has granted conditional or provisional approval to new technologies (other than those notified under BMW Rules) for treatment of BMW. These are plasma pyrolysis, dry heat sterilization and encapsulation of waste sharps, sharp blaster (needle blaster), and PIWS-3000 technology (Static/Mobile). Various new technologies for BMW disposal are categorized into four groups – thermal processes, chemical processes, irradiative processes, and biological processes.
Thermal processes are grouped into three – low, medium, and high:
- Low heat technologies operate between 93-177°C and include microwaves and autoclaves. The advantage of using microwaves for BMW disposal is minimal emissions. Its disadvantages include requirement of high capital for setup, problem of odour near the machine, and there is a chance of leak of microwave energy.
- Medium heat technologies operate between 177- 540°C and include reverse polymerization and thermal depolymerization.
- High heat technologies operate between 540- 8300°C and include pyrolysis – oxidation, plasma pyrolysis, induction-based pyrolysis, and lase-based pyrolysis. Advantages of this system are low emission rate, waste residue is inert and sterile i.e., environment friendly, and there is reduction in volume (95%) and mass (80%–90%). Its disadvantages include high capital cost, high operation cost, high electrical usage, limited lifespan of plasma torch and possible generation of dioxins in poorly designed setups.
Chemical‑based technology
is most suitable for treating liquid waste such as blood, urine, stools, or hospital sewage. Chemicals used are sodium hypochlorite (1-12%), hydrogen peroxide (30 %), Fenton reagent (0.3 g in 10 ml), chlorine dioxide, calcium hydroxide, glutaraldehyde and peracetic acid. The exhaust air in this technology has to be passed through HEPA filters to safeguard against aerosol formation during shredding which is mandatory. It is a fully automated technique, easy to use, with ease of discharge of liquid effluent into the sewage, and no by-products of combustion. The disadvantages include toxic by-products due to large-scale chlorine and hypochlorite use such as dioxins, halo acetic acid, and chlorinated aromatic compounds which are released wherever sodium hypochlorite is used.
Non-chlorine‑based technologies use either gas, liquid, or dry chemicals:
- Dry chemical: SteriEcocycle 104 uses a portable chamber for collecting waste into which a peracetic acid-based decontaminant vial is added. After 10–12 min, peracetic acid disinfects the waste and aerosolized pathogens are prevented from escaping by use of HEPA filters. The liquid effluent is discharged into a sewer and the waste is sent as regular trash.
- Liquid chemical: Waste reduction (WR) technology uses alkaline hydrolysis at high temperature to convert human and microbial waste into neutral aqueous solution. It is used for human/tissue waste, body fluids, and degradable bags. In addition, it can handle chemotherapy waste.
- Gas: Lynntech’s technology uses ozone for decontamination of BMW. Being a strong oxidant, ozone destroys microbes and converts into molecular oxygen.
