Waste Disposal

Hazardous chemical waste including solvents, acids, and reagents should never be disposed of down sewer drains. Waste must be separated based on chemical compatibility in order to avoid violent reactions and disposed of in the proper waste containers following the practices described by the Office of Environmental Health and Safety at your academic or industrial workplace.

On the linked webpages, we will examine some of the important issues specific to waste disposal of the following types of materials/reagents:

Chemical

Chemical waste disposal is an increasingly expensive problem for all workplaces using chemical reagents. All chemical waste must be identified properly before it can be disposed. Depending on the volume, toxicity, and/or reactivity of the reagents you wish to dispose of, proper disposal may be very expensive so it is important that you make a conscious effort to order the absolute minimum amount of the reagents that you need and use the minimum amount needed in order to carry out your experiments. If practical, think about how you might reclaim by distillation and/or precipitation your reagents and solvents and thereby minimize the amount of waste you generate in your work.

Labeling

Bottles containing chemical waste must be properly labeled. Labeling should include the words “hazardous waste.” The label should also include the names and relative amounts of the major chemical reagents and/or solvents and the date that the bottle was filled. Be sure to write out all chemical names – do not use chemical formula like “H2O” or abbreviations such as “ACN” or “DMF.” Do not put a date on the bottle until it is completely filled and ready for pickup.

Storage

Chemical waste should be disposed of in glass or polyethylene bottles. Plastic coated glass bottles are best for this purpose. Aluminum cans which are easily corroded should not be used for waste disposal and storage. In some laboratories, workers recycle solvent bottles and use them for chemical waste storage and disposal. If your laboratory does this, be sure to completely fill and empty the solvent bottle a minimum of three times before using it for waste and be sure to completely remove or deface the bottle’s label. Waste bottles that are in use should be placed in a secondary container such as a plastic tub, preferably inside the hood. This location should be clearly marked with a sign indicating that it is the “Satellite Waste Disposal Area” for your laboratory. Before adding waste to a waste bottle, inspect the waste bottle label and make sure that the materials you are adding are compatible with the bottle’s contents. For example, don’t mix organics and acids. If you are in doubt, start a new waste bottle. Bottles should be capped unless you are in the actual act of adding waste to the waste bottle. If you use a funnel in order to add waste the funnel must be removed when you are finished and the bottle capped.

Don’t completely fill a waste bottle. Always leave at least one inch at the top of the container. As soon as a waste bottle is completely filled, be sure to put the date on the label and contact your Office of Environmental Health and Safety to schedule a chemical waste pickup. The rules regarding the scheduling of waste pickup are very rigid in most laboratories and filled waste bottles need to be removed from the research laboratory within three days of the date indicated on the waste bottle.

Biological And Medical

Regard all cultures, blood, and tissue samples, all waste products produced by biological systems, and any materials that come in contact with biological systems as potentially hazardous. Exposure to biohazards can occur by aerosol (inhalation), accidental ingestion, skin or eye contact, and by accidental puncture of the skin (needles).

Waste and any materials contaminated with biohazardous materials must be decontaminated and disposed of as regulated medical waste. This includes all tissue samples, needles, syringes, scalpels, etc. Be sure to contact your Office of Environmental Health and Safety concerning the proper practices associated with the handling and disposal of biohazardous waste.

Decontamination of Medical Waste

As appropriate, all contaminated materials and surfaces should be either autoclaved (steam sterilization) or treated with 1:10 (v/v) bleach solution to disinfect.

Disposal of Medical Waste

Disinfected needles, syringes, razor blades and other sharps should then be placed in labeled sharps containers. All other biohazardous waste should be placed in biohazard bags, and then placed inside medical waste boxes. The bags should be labeled in indelible ink with the date, name, location, and phone number of the laboratory supervisor.

Animal and Patient Waste Disposal

Waste from animals and patients should be viewed and treated as potentially infectious biohazardous waste. Animal bedding, carcasses, and human and animal tissue and waste samples should be autoclaved before disposal in the medical waste stream. Be sure to contact your Office of Environmental Health and Safety concerning the proper practices associated with the handling and disposal of biohazardous waste.