In a clinical, science or school laboratory, managing waste is a primary concern for overall laboratory safety. There are a lot of priorities in today’s laboratory arena that demands attention. With an effective laboratory waste management program, you can positively impact inventory control, staffing to workload and budget management issues.
Most laboratories have an accurate understanding and management of waste. But the fact remains that controlling laboratory generated waste is controlled by your local authorities and numerous multiple national organizations. Your first step to manage your lab waste is to learn and know the difference between the various waste streams. You also need to know how to train your staff and students on how to segregate waste properly. Since waste management is also a concern in some school labs, it is essential students are made aware of how to properly handle and dispose of waste.
Segregation of Waste
Some mix their waste for convenience as it is believed this approach is more straightforward than providing regular training, attention to detail, or updates if they are only using one type of waste container. This approach is expensive and creates unnecessary environmental burdens.
There are at least three separate streams of waste generated in a laboratory:
- Regular- non-regulated waste
- Regulated medical waste (RMW)
- Hazardous waste (chemical)
Regulated medical waste (RMW) can be further broken down or segregated into biohazard waste and medical sharps. Each of these three streams is regulated differently and are overseen by numerous federal and local agencies.
Regular Non-Regulated Waste
This form of waste is non-contaminated trash which is not regulated and is able to be disposed of at your local landfill. This form of debris is also the cheapest to dispose of, so it is essential your lab uses this form of disposal for as many permissible items as possible.
Some of the items that fall under this stream include
- Disposable lab coats
- Gauze (as long as it is not saturated with blood)
- Plastic transfer pipettes, and gloves
- Petri dishes
- Plastic labware
- Sturdy centrifuge and test tubes
- Uncapped, washed bottles
- Gloves and paper towels with no traces of significant contamination
Most of the other lab wastes are removed by third-party providers who generally charge by weight.
Regulated Medical Waste (RMW)
Generally, RMWs are materials contaminated with blood. These items should be in biohazard-specific containers that have a tight fitting lid, and they should be appropriately labeled. The bags for these containers should be red or orange colored. Containers for RMW come in a variety of sizes depending on your facility location and the state laws that govern your waste disposal and transport.
The Centers for Disease Control (CDC), the World Health Organization (WHO), and the U.S. Environmental Protection Agency (EPA) all agree these wastes should be classified as infectious wastes:
- Lab cultures and stocks
- Blood and blood products
- Pathological wastes
- Waste created from patients in isolation with contagious diseases
- Chemicals and hazardous materials used in patient treatment and diagnosis
The category for sharps is further broken down into:
- Pasteur pipettes, broken vials, pipettor tips, and slides used in a laboratory and are contaminated with biologically hazardous material
- Syringes that have a needle attached
- Razor blades
Some of the RMW disposal containers or bags end up in biohazard landfills. In these landfills, they have special assembly and maintenance as the containers and bags are not good for the environment.
RMW sharps include glass, needles and any other item that breaks easily and creates a sharp edge. These items should be placed in sharps containers. Other items to go into these containers include glass containers, agar plates, and wooden applicator sticks.
All of these ‘sharps’ should be placed into the appropriately colored ‘sharps’ container whether they are broken or not. Sharps containers should be puncture resistant, leakproof, closable and constructed of a plastic carboy. Do not fill the containers to the top. A 5 cm clear space between the top and the objects in the container is desirable.
None of these items should ever be placed in a plastic bag as disposal because if they break during transport, they can cause a dangerous exposure to someone handling them.
Most waste handlers remove the sharps containers from the lab and then incinerate them. Some vendors offer recycled sharp containers which are only possible if they have been treated through incineration.
It can cost your lab a lot of money if your staff mistakenly places materials in RMW bags that do qualify for this type of waste. Adding volume and weight to your waste increases the disposal costs, and the use of specialized biohazard bags and specialized sharps containers will add to the cost of your waste management. Ensuring your staff and students are appropriately trained to segregate waste materials is an essential part of your departmental finance management as well as promotes staff and student safety.
Disposing of Hazardous Waste in a Lab
A primary responsibility of anyone working in a lab, whether in a medical, science or school facility is to be able to positively identify all hazardous waste materials being generated. The identified wastes should be appropriately segregated, labeled, placed in appropriate containers, and stored until removable disposal is completed.
These are some of the typical liquid hazardous wastes:
- Liquid solvent waste
- Vials containing liquids for extraction, digestion, or preservation
- Specimen preservatives such as formaldehyde, paraformaldehyde, alcohol, etc
- Unused laboratory reagents that are no longer needed
- Organic synthesis liquids
- Liquids associated with TLC or HPLC studies
- Waste liquids from DNA extractions
- Photographic and X-ray related chemicals
These are some of the typical solid hazardous wastes:
- Absorbent materials used in chemical processes
- Slides used with contaminated or hazardous chemicals
- Disposable pipette tips used to transfer or measure chemicals
- Electrophoresis gels which contain Ethidium Bromide
- Gloves used as protection against hazardous chemicals
- Weighing papers or boats with chemical reagents
- Rags, paper towels, or vermiculite used as cleanup of chemical spills
- Ion exchange and filters materials used during a chemical process
Once the material has been identified as hazardous, it must then be labeled properly for disposal. To comply with the EPA’s (Environmental Protection Agency) Hazardous Waste requirements, you must understand the importance of proper identification of these materials.
To be considered a hazardous waste, the material must meet one of these three criteria:
- The waste must contain any chemical listed by the EPA as being hazardous. There are three lists set out by the EPA listing substances that lab workers need to be familiar with- F-List is a collection of spent solvents, the P and U-Lists are common chemical products
- The waste must exhibit any of these four characteristics- toxicity, reactivity, corrosivity, or be flammable.
- The waste’s packaging, ingredient list, product website or MSDS states the substance can be dangerous to the environment or humans.
Workers or students in the lab are directed to place appropriate labels on containers before they put any material into it. Labeling first helps to reduce the chance of an unknown waste being placed into the container. As you set new items in, you should update the label to include the new material being placed inside. Do not use abbreviations when labeling, write full names of all materials.
The EPAs terminology for affixing or attaching proper labels means the label must be physically connected to the container. You cannot have a separation between the label and the container it refers to. The labels must be securely attached and cannot be wound on with wire as an example.
When EPA states the label must be associated with the container, this means there has to be a labeling system that will allow you to track the information back to specific containers. This association would include the use of a spreadsheet, log book, or barcoding.
DOTs reference to a label is specific. Their regulations state labels are to be diamond-shaped and placed on non-bulk containers to resemble bulk container placards. Anything else on a non-bulk container is considered a marking. All DOT hazardous waste labeling is based on international standards.
Secure handling of hazardous waste involves the critical step of properly marking and labeling all containers. Uniformity in how this is done is dictated by the DOT (Department of Transportation) and EPA (Environmental Protection Agency). These two agencies have a specific and different system of labeling then OSHA (Occupational Safety and Health Administration) or the CFR (Code of Regulations). OSHA and CFR offer labeling systems for hazardous materials that are not designated as waste.
Regulations Governing Medical Waste
There are regulations governing the treatment, labeling, handling, storage, disposal, and transporting medical waste materials. Many state environmental and health rules define which waste materials require special storage, processing, labeling, and segregation as well as these federal agencies:
- The DOT (Department of Transportation) has rules for packaging and transporting of these wastes
- OSHA regulates worker safety, waste handling, and labeling
- RCRA (Resource Conservation and Recovery Act) has guidelines which control the management of hazardous wastes and materials, including pharmaceutical wastes
- The NRC (Nuclear Regulatory Commission) manages and rules how radioactive waste is managed
- The DEA (Drug Enforcement Agency) regulates the disposing of and handling of controlled substances like the narcotics
- Clean Air Act maintains proper handling of emissions from incinerators
- The Clean Water Act defines which chemicals are safe to be disposed of through your drain system
How Professional Waste Disposal Helps
Professional waste disposal services are fully trained in the disposal of hazardous waste. They understand the laws governing the handling, transporting and disposing of hazardous materials in your state or county.
You can receive training for your laboratory personnel or students to ensure the proper labeling, marking, containing, storing and disposal is being correctly done and that all federal agency mandates are being met. These materials pose a threat to your staff or students, the environment, and the company disposing of your waste. It is critical anyone involved with handling hazardous waste material has the proper training.