Clinical laboratories generate a variety of hazardous waste materials that need to be managed properly to prevent harm to human health and the environment. Some of the common hazardous waste materials generated in clinical laboratories include:
1. Chemical waste: This includes solvents, reagents, and other chemicals used in laboratory tests and procedures. These chemicals can be flammable, corrosive, toxic, or reactive and must be properly segregated, stored, and disposed of according to regulations.
2. Biological waste: This includes blood, body fluids, tissues, and other biological materials that may be contaminated with infectious agents. Proper handling and disposal of biological waste are crucial to prevent the spread of infections.
3. Sharps waste: This includes needles, syringes, scalpels, and other sharp objects used in laboratory procedures. Sharps waste must be collected in puncture-proof containers and disposed of in designated sharps disposal containers.
4. Radioactive waste: Some laboratories use radioactive materials for diagnostic imaging or research purposes. Radioactive waste must be properly stored, handled, and disposed of according to regulations set by the Nuclear Regulatory Commission.
SEGREGATING LABORATORY HAZARDOUS WASTE
Laboratory hazardous waste must be segregated into three categories: solid, liquid, and gaseous.
Solid hazardous waste includes infectious or pathological wastes, culture dishes, discarded chemical reagents, and glassware. It can be placed in plastic bags and stored as-is, as long as the area it's being stored in is properly ventilated.
Liquid hazardous waste includes chemical solutions containing acids or bases, organic solvents, and water from chemical reactions. These wastes must be neutralized before being disposed of; otherwise, they could cause burns or create an explosive environment.
Gaseous hazardous waste contains toxic gases that pose a risk to humans because they can irritate the eyes, nose, and throat or cause headaches and nausea. Gases such as methane, hydrogen sulfide, and carbon monoxide are all examples of gas-based laboratory waste products.
HAZARDOUS WASTE TREATMENT AND DISPOSAL
Treatment methods can be divided into two categories: environmentally acceptable or technologically enhanced methodologies. Specifically, these methods include physical/chemical treatment such as thermal treatment (incineration), chemical treatment (acid/alkaline hydrolysis), and biological treatment.
Disposal refers to the final resting place of hazardous waste after all possible treatments have been applied. Waste disposal may be by either landfill disposal or incineration. Solid chemical wastes are usually disposed of in landfills or incinerated, but radioactive chemical wastes require special disposal procedures. Infectious agents are treated differently from other laboratory waste because they are usually highly regulated by the government.
In general, environmentally acceptable methods are preferred for laboratory hazardous wastes because they are less costly than technologically enhanced methods.
PREVENTING HAZARDOUS WASTE ACCUMULATION
Some common concerns associated with hazardous waste management are disposal methods, toxicity, cost-effectiveness of treatment options, and the financial impact on lab budgets.
There are many ways to prevent hazardous waste accumulation in your lab:
- Dispose of small amounts immediately after use
- Do not leave chemicals exposed in flasks or bottles overnight
- Don't collect larger amounts than you need for immediate use
- Always keep chemicals in their original containers (bottles, flasks, etc.)
- When decanting material, transfer it into smaller containers
- Use reusable glassware instead of disposables (such as pipette tips).
- Labels should include the name of the product, date prepared, date opened, date expires, usage information, and contact information (name, phone number).
MANAGING BIOHAZARDS
A biohazard is a technical term that means any biological agent that poses a threat to healthy living organisms. It can be a virus, bacteria, or other pathogens that cause illness and disease in a living system. There are levels of biohazard wastes based on their potential risk if they are released into the environment. Although these levels have been assigned by the Centers for Disease Control (CDC) to be 4 biohazard levels.
- Level 1: Inanimate objects that come in contact with infectious material.
- Level 2: Contaminated sharps, laboratory cultures from potentially infected patients, and other items that have been exposed to infectious material.
- Level 3: Clinical specimens that have been collected from potentially infected patients and have been identified as containing infectious material. These items must be placed into a leak-proof container before transport.
- Level 4: Patients who are known to be infected or are suspected of being infected with a pathogen that has the potential to spread through airborne transmission.
OSHA REGULATIONS
Although, hazardous waste is classified into different categories based on its characteristics and potential risks to human health and the environment; the Occupational Safety and Health Administration (OSHA) does not specifically mandate a standardized color-coding system for hazardous waste in laboratories. OSHA does require that hazardous materials in the workplace, including those generated in laboratories, where it should be properly labeled and identified to ensure the safety of workers and compliance with regulations. These labels may include information such as the type of hazard (e.g., flammable, corrosive, toxic), the contents of the container, and any necessary precautionary measures. Some laboratories may choose to use color-coded labels or stickers such as red labels for highly infectious waste, yellow labels for infectious waste, black labels for non-infectious waste, and so on.
Laboratory personnel need to be trained on the proper labeling and identification of hazardous waste in accordance with OSHA regulations and any other applicable guidelines or standards. This helps ensure that workers are aware of the potential hazards associated with the waste and can take appropriate precautions to safely handle, store, and dispose of hazardous materials in the laboratory.
Here are some links that may be helpful:
1. OSHA's guidelines on hazardous waste management: https://www.osha.gov/hazardous-waste
2. CDC's guidelines on laboratory biosafety: https://www.cdc.gov/safelabs/resources-tools/medical_waste_management.html
Please note that waste management guidelines may vary depending on the specific regulations in your location, so it is important to consult with local authorities or regulatory agencies for further guidance.