Be wary of waste

The hazards associated with improper disposal of medical waste come under the microscope at a recent seminar

Having been involved in laboratory medicine for most of my academic life, I was motivated to participate in the half-day seminar on ‘Clinical and Medical Laboratory Waste Disposal’, conducted by the Sri Lanka Association of Testing Laboratories (SLATL).

The seminar held on May 7 at the Industrial Technology Institute (ITI) was attended by the Director and Secretary of Private Health Services, Ministry of Health Dr. Amal Harsha de Silva, Professor Lal G. Chandrasena, Director General, Nawaloka Hospital - an authority on Laboratory Medicine and over 50 members of the SLATL representing a spectrum of laboratories - medical and non medical.

Presentations were made by Dr. K.A.C. Wickramaratne of the Faculty of Medicine, University of Ruhuna, the writer as administrator of Durdans Hospital’s Diagnostic Laboratories and S. Kularatne - Senior Medical Executive, Package Care Ltd on ‘Clinical Waste Disposal’, ‘Waste Disposal off Medical Testing Laboratories’ and ‘Medical Waste Management’ respectively.
During the discussion sessions, the following questions surfaced:

Waste from hospital is varied in quality and quantity. All non-reusable materials that have come into contact with patients (swabs, dressings, gloves, hypodermic needles, syringes, catheters, wastewater, etc.), disposable materials (plastic vials, left over medicines, etc) and any other contaminated item (air filters, flooring, etc) will have to be considered as bio-hazardous. The disposal of such items has to be properly managed. To put it in a nutshell, the failure of safe disposal of medical waste can result in the pollution of air that we breathe and contamination of water that we drink. We would have never thought of hospital waste in this way, thus far!

Of the hospital waste and medical laboratory waste, some of it is combustible and some non-combustible. Both, combustible and the non-combustible waste must be disposed of observing environmental safety procedures. The method of choice of removing combustible waste is by incineration, in properly constructed incinerators. Burning of hospital and medical testing lab combustible waste must not take place in the open and in built-up areas.

In a medical testing laboratory, many combustible materials such as left over body parts and tissues (biopsy specimens), culture swabs, cultured bacteria and fungi (in microbiology), leftover blood and other body fluids after testing and a whole gamut of chemicals (with known and unknown toxicity) accumulate. The chemicals include fixatives, preservatives, enzymes, chelating agents, dyes, catalysts and detergents. All such materials are hazardous.

Disposal of this laboratory waste by combustion must not take place in the open and in built-up areas. Medical laboratory liquid waste such as left over blood specimens, urine specimens and spent chemical must never be poured into the laboratory sink. Patients’ blood and urine (if infectious) can contain disease-causing (pathogenic) organisms that can come back to us. Disposal of laboratory chemicals into the sewerage system has to stop. As the sewerage system is not a closed system, the volatile chemicals can enter into the air we breathe, can enter into drinking and irrigation / sea water – hence find a way into our food chain. Any chemical, in high enough amounts is deleterious to our health.

Increasing environment pollution, without doubt, is singled out as a factor predisposing us humans to ill health. Pollution-related illnesses and an increase in the nature of health consciousness are two factors that take more and more people to hospitals, nowadays. This and the tendency of doctors to request more laboratory investigations coupled to promised income generation has led to more and more medical testing laboratories springing up. So much so, there is a high density of medical testing laboratories in any city or town.

Some of these medical testing laboratories have come up as an integral part of new hospitals and channelled consultation outfits. But, a large majority function as isolated entities, scattered among shops within shopping areas of towns.

In a medical testing laboratory, the reception area from where reports are also issued is usually kept clean to attract clients. Inside is the testing area, which is not accessible to the client. It is at the rear end of the lab, that we encounter much of the lab waste.

All patients do not come to a lab because of infectious disease. So all patient samples are not infectious. However, the ground rule is that laboratory personnel must treat and dispose of all patient samples as if the samples are potentially bio-hazardous and capable of transmitting illness.

The super grade medical testing labs have the capability of implementing safe waste disposal procedures, of course at a cost. However, the middle grade and mini medical laboratories do not possess the financial resilience to implement safe waste disposal procedures to the letter. Considering that these laboratories too provide patients a commendable service and the constraints they face with regard to lab waste disposal, the authorities will have to assist these labs in waste disposal.

We have to accept the fact that, the medium and mini-grade medical testing laboratory can never think of investing huge sums of money to establish its own waste disposal setup. Nor can a laboratory with limited manpower and a poor knowledge of scientific safe waste disposal adhere to waste disposal as dictated by legislation. As we need the services of these middle grade and micro level medical labs, we have to think of other ways. One such way is for an agency / agent to come into operation taking over the part of waste disposal off these labs, indeed for a payment.

Such an organisation should be the agent that bridges the medical lab with the appropriate governmental authorities, and in particular with the Central Environmental Authority. This agency should undertake the role of disseminating appropriate information from the authorities to its client (rules, regulations, ways and means). The agency must ensure that waste is sorted out, collected and transported in the proper manner to the disposal site. The agency must be given right of access to a disposal site and its use. The site must be a government land from which site the risk of pollution is minimal if not absent. The agency must have people knowledgeable in medical biological waste and medical laboratory waste and safe disposal methodology. The agency must have the financial capability for proper transport, incineration and burial of waste, as appropriate.

The super grade medical testing laboratory, which usually is a part of a hospital, can use the hospital’s waste disposal outfit, comprising an incinerator and burial site, etc. But, of course the medium and mini-grade labs cannot afford to have an incinerator each. They must have access to a common incineration, landfill and burial sites.

The capital investment of an incinerator for bio-medical waste incineration (waste weight / volume reduction >90% and minimal extract emission) is over millions of rupees. If individual labs were to have one incinerator each, imagine the foreign exchange required to procure the incinerators and the running cost of the incinerators, which includes the fuel bill and the electricity bill.

Overall, the seminar brought out that medical waste and medical laboratory waste, unless properly managed and safely disposed of, could cause environmental pollution causing a threat to our health and well-being. There is more to medical testing lab waste, that the public is unaware of, both in amount and in danger (pathogenecity) and also in toxicity to humans.