Medical waste is biohazardous and presents a great threat to life as long as it exists. Medical waste is waste generated from medical procedures and health care services. It contains higher amounts of toxic substances and infectious microbes than domestic waste, and it can sicken or cause disease to humans and animals.
Medical waste comes from health care premises such as hospitals, clinics and doctor’s offices. Pharmaceutical factories, independent laboratories and veterinary clinics also produce a significant amount of medical waste. In smaller degrees, homes also generate medical waste as well. Therefore, medical waste is not as uncommon as many people believe.
Medical waste often comes from procedures used in treatment of persons or animals that are sick, so it contains highly infectious microbes that can cause disease or very toxic substances that can harm life. Examples of medical waste include used syringes, soiled dressings and bandages, gross body parts, laboratory cultures and diagnostic samples, blood, pharmaceuticals and medical devices and radioactive materials.
People who are at risk of getting harmed from medical waste include health workers like doctors, nurses and lab technicians, waste and maintenance workers, and people in the community. People who handle medical waste must wear personal protective equipment to reduce risk of harm; it includes an overall gown, double latex or nitrile gloves and face masks.
Medical waste is never recycled, sorted or segregated at point of collection because it is highly toxic and infectious to people.
Different methods for different types of medical waste
The method of managing medical waste differs according to its type. This is necessary to effectively contain the waste with the smallest possible risk of harm or injury to others.
Because not all medical waste can be eliminated quickly, it is necessary that proper procedures must exist to contain it for storage. Ideally, stored medical waste must be separated from other kinds of waste and must be properly labeled and marked to prevent tampering which might release it into the vicinity and cause harm.
Generally, all types of medical waste are packed in special containers. Many of these containers are double-walled to reduce spills in case of breakage, and have absorbent linings to absorb liquids. A lot of containers are also specially-made to handle specific types of medical waste.
Methods used for different categories of medical waste:
Cold storage
This option is for medical waste that contains significant portion of decomposing substances, like pathological waste, which consists of gross body organs, tissues and amputated limbs. Cold temperatures in freezers delay decomposition of solid organic wastes, which is necessary until they can be disposed.
If not stored in cold temperatures, tissues rapidly decompose and emit a bad putrefying smell that is unpleasant to people and attracts vectors, like mice and flies, that may spread disease-causing bacteria.
Autoclave
Autoclave is an instrument used for sterilizing. It does so by the means of high-pressure saturated steam at about 121 C. It heats objects for 15-20 minutes to kill almost all microorganisms, including spores. It is widely used for processing medical waste, like syringes, which can withstand the heat of the steam. It is long used for processing sharps to kill pathogens, including hepatitis B viruses and HIV, and reduce harm before it can be eliminated.
Many hospitals and medical centers treat eligible types of medical waste using giant autoclaves. Though it’s effective in reducing posed harm from sharps, it cannot be used for other types of medical wastes like pathological and radioactive wastes.
Chemical mixing
Many institutions also process medical waste by mixing them with chemicals to reduce harm and infectiousness. Strong chemicals can kill a lot of pathogenic microbes, and therefore it is an option for kinds of waste such as pathological and soft-tissue waste.
Chemicals are also use to render some poisonous medical waste less toxic. In some factories that produce pharmaceutical waste, chemicals are used to neutralize or reduce toxicity of the waste. Again, it is helpful for reducing hazards of medical waste until it can be disposed.
Temporary burial
Medical waste that emits ionizing radiation such as radioactive pellets used for bracytherapy (cancer treatment involving radiation) and from decommissioned nuclear imaging equipment are often temporarily buried to prevent release of radiation to the environment. This is done until it can be collected and processed more properly.
Radiation from such items is lower compared to spent fuels in nuclear power plants. In addition to packaging them in specially made containers, burial prevents others from tampering and mistaking radioactive metals as valuable scrap.
Methods to dispose medical waste
Incineration
This is the most commonly used method to dispose medical waste; at least 90% are disposed in this way. Incineration eliminates medical waste by subjecting it to very high temperatures (at least 800 C) to burn it into ash and carbon dioxide.
Although many regions around the world forbid burning, incineration is the only method to deal with infections and highly toxic medical waste. To help comply with clean-air laws, medical waste is burned at incinerators at maximum capacity to reduce impact on the environment. Because of that reason, a lot of medical waste must be stored first until the capacity is enough to justify burning.
Deep burial
This method is mostly reserved for medical radioactive waste. Although radioactive materials can be recycled (like some forms of spent nuclear fuel), the amount of useful material from medical radioactive waste is too low to justify the expense and technology.
Medical radioactive waste in hospitals is first packed into radiation-proof containers, like thick concrete, and left to undergo radioactive decay, which lessens amount of emitted radiation, but it takes many years (10+).
Waste with no detectable radiation maybe disposed as ordinary waste. But for those that still have radiation, the only option is deep burial to keep it away from human vicinity.
But problems still remain. There are limited deep burial facilities that are available. And, the cost of processing medical radioactive waste and compounding maintenance is very high for many hospitals. Thus, many resort to reducing non-radioactive alternatives in an effort to slim down production of radioactive waste.