Medical waste, also known as biomedical waste, refers to waste generated in the process of diagnosis, treatment, immunization, or research. Although region-specific, the impact of medical waste on the environment is one that cannot be ignored. Medical waste is a source of land and water contamination especially if it is not rendered harmless before disposal.

About 85% of the waste generated from health care centres is non-hazardous. However, the remaining 15% is considered hazardous material that is either toxic, infectious, or radioactive according to WHO. Annually, approximately 16 billion injections are administered globally but many needles and syringes are not disposed of properly.

Although it is considered a method of medical waste disposal, open burning and incineration of health care waste can result in the emission of furans, dioxins, and particulate matter. Medical waste must be properly contained, segregated, and incinerated using the right equipment to prevent any adverse health and environmental impacts. For instance, the unintended release of biological hazards like drug resistant microorganisms into the environment could potentially harm the public.

 

TYPES OF MEDICAL WASTE

Infectious waste – waste that is contaminated with blood and other bodily fluids from discarded diagnostic samples, cultures, and stocks of infectious agents either from lab work or waste from patients with infections i.e., bandages, swabs, COVID-19 test kits, disposable medical devices.

Pathological waste – human tissue, organs or fluids, body parts and contaminated animal carcasses.

Sharp waste – needles, blades, syringes and disposable scalpels.

Chemical waste – solvents and reagents used for laboratory preparations; disinfectants, sterilant,  heavy metals contained in medical devices (mercury in thermometers) and batteries.

Pharmaceutical waste – expired, unused and contaminated drugs and vaccines.

Cytotoxic waste – waste containing substances with genotoxic properties (highly hazardous substances that are mutagenic or carcinogenic) such as cytotoxic drugs used in cancer treatment and their metabolites.

Radioactive waste – products contaminated by radionuclides including radioactive diagnostic material or substances from radiotherapy.

Non-hazardous waste – waste that does not pose any particular biological, chemical, radioactive or physical hazard for example office waste.

MAJOR SOURCES OF HEALTH CARE WASTE

 

• Hospitals and health facilities
• Research centres and laboratories
• Mortuaries and autopsy centres
• Nursing homes
• Blood banks and collection services
• Animal research and testing laboratories

It should be noted that High Income Countries tend to generate more hazardous waste than Low Income Countries (LICs). However, medical waste from LICs is often not separated into hazardous and non-hazardous waste. Therefore, the quantities of hazardous waste could be higher. Alarmingly, in LICs some medical operators tend to mix medical waste with domestic waste which can be potentially dangerous.

EFFECTS OF MEDICAL WASTE ON THE ENVIRONMENT

 

• The healthcare industry accounts for 4.4% of worldwide carbon emissions which is equivalent to greenhouse gas emissions from 514 coal power plants. This would make it the fifth-largest carbon gas emitter if categorized as a country.
• Medical waste contains harmful microbes that could potentially affect health workers, patients, and the public. It may also expose people to drug resistant micro-organisms which could have detrimental effects.
• It could also contribute to air pollution through the incineration of medical waste that will release particulate matter, dioxins, heavy metals (mercury, lead, cadmium) and furans into the atmosphere. Incineration also generates ash residue that contains traces of the chemical, biological and radioactive compounds. If not treated properly it could be an environmental hazard.
• Untreated medical waste should be disposed of in the right manner. When this waste is disposed of in landfills it can lead to the contamination of soil, surface and ground water.
• Chemical waste from hospitals can lead to the release of chemical compounds into the environment. These include lab reagents, disinfectants, or solvents. For instance, formaldehyde – used in disinfection, preservation, and embalming, breaks down into formic acid and carbon monoxide when exposed to the atmosphere. These compounds are harmful and can make animals sick, affect their ability to breed, change their behaviour and appearance or reduce their lifespan.
• The increased use of single-use products such as masks, personal protective equipment, bandages, gauze, or specimen collection containers, result in the disposal of large amounts of plastics.

WHAT CAN BE DONE?

• Raising awareness of the risks related to health care waste.
• Promoting safe practices and regulations that limit the volume of wastes generated and ensure that waste segregation is a priority.
• Advocate for environmentally friendly management options to safeguard the public during collection, handling, storing, transporting, disposing and treating waste.

Medical waste can have serious health and environmental impacts however, reusing single use products like bandages and gauze may lead to the transmission of infections to patients or reduced use of energy could put patients’ lives at jeopardy, but on the other hand both scenarios lead to increased environmental pollution. Therefore, it is difficult to know where to draw the line between environmental conservation and public health. However, this does not mean wastefulness should be encouraged in medical centres.

SOURCE

https://www.who.int/news-room/fact-sheets/detail/health-care-waste