22.1  Introduction

The following sections provide hazardous waste management guidelines and procedures. This chapter covers the following topics:

22.2  General Information

Hazardous waste disposal is governed by the Environmental Protection Agency (EPA) and the Tennessee Department of Environment and Conservation (TDEC) through State and Federal regulations. The purpose of environmentally sound disposal methods is to prevent harm to the water, land, and air. UTIA complies with hazardous waste disposal regulations by means of the Hazardous Waste Management Program, as specified in this section.

All areas that generate hazardous waste must have a door sign which designates where the waste is stored in that area and what type of waste it is.  In addition, the location  inside the room must be designated by a sign (yellow, black letters, stating: "Hazardous Waste Storage Area.")

22.2.1  Permits and Requirements

UTIA is a "Large Quantity Generator" of hazardous waste. The Institute has two generator permits: one for Veterinary Teaching Hospital, and one for Teaching and Research portions of the Institute. The Safety Office will assist any department or research and education center branch station in determining its hazardous waste disposal needs.

22.2.2  Penalties of Noncompliance

Noncompliance with any hazardous waste regulation may result in substantial fines, penalties, and citations for the University. In addition, individual generators may be personally liable. Generators may be cited or fined for numerous types of violations. Violations range from improperly labeling a waste container to intentionally disposing of hazardous waste incorrectly.

22.2.3  Role of the Department of Environmental Health & Safety and the UTIA Safety Office

The Department of Environmental Health & Safety administers the Hazardous Waste Management Program for all of the Knox campus and the Institute. Compliance with this program is very demanding - it requires full cooperation by all campus entities. The main focus of this program is chemical waste management. The program does not include procedures for the management of radioactive, infectious, biological, or nonhazardous waste. (For questions on these topics, please call the UTIA Safety Office.)

The Department of Environmental Health & Safety (DEHS) arranges for the collection and disposal of waste. DEHS and the UTIA Safety Office also maintain permanent records of all disposed waste. Contact the UTIA Safety Office for information on hazardous waste disposal not found in this section.

22.3  Hazardous Waste Categories

22.3.1  Definitions

22.3.2  Types of Hazardous Waste

An item is considered waste when the owner determines that the material is no longer useful and needs to be discarded. An item is considered to be hazardous waste if it also meets one or more of the following characteristics:

  1. It is a chemical component that is designated hazardous by the E.P.A. (Call the Safety Office if you are unsure about the designation of any particular chemical.)
  2. Any mixture that contains a listed hazardous waste and a nonhazardous waste.
  3. Material meets the definition of one of the following:

Individual departments are responsible for properly identifying the hazardous waste they generate and for following University disposal procedures.

22.4  Containers, Tags, and Collection

Proper containment, tagging, collection and disposal are essential to the success of the Hazardous Waste Program.

22.4.1  Filling Waste Containers

Hazardous waste collection containers must be in good condition, must not leak, and must be compatible with their hazardous contents (e.g., do not use metal containers for corrosive waste or plastic containers for organic solvents.) All containers must have suitable screw caps or other secure means of closure. When large waste containers (greater than 10 gallons total volume) are warranted, contact the Safety Office for assistance.

If you are reusing a container to accumulate waste, destroy the original product label. A new label must be placed on the container. EPA regulations require that waste containers be labeled with the identity of the contents and the words "Hazardous Waste." (see below.)

IMPORTANT: Never overfill hazardous waste containers. Expansion and excess weight can lead to spills, explosion, and extensive environmental exposure.

General Guidelines:

  1. Hazardous waste containers for liquids are generally rated by volume capacity. Leave extra room in liquid containers to allow for contents expansion.
  2. Do not fill jugs and bottles past the shoulder of the container. The shoulder of the container is the place where the container begins to slope in towards the neck.
  3. Fill closed head drums to leave approximately four inches of space.
  4. Hazardous waste containers for solids are generally rated by their weight capacity and volume capacity. Take care not to exceed the weight capacity of a solid container. Weight is generally not a problem for jars and open head cans (5 gallons or less), but it can be a problem for open head drums (larger than 5 gallons.) Depending on weight requirements, you may fill containers for solids within two inches of the closure.

IMPORTANT: Keep all waste collection containers closed except when adding or removing material.

22.4.2  Completing Labels

Follow these guidelines for completing hazardous waste labels:

  1. Fill out the label.  DATE the label when the container is full and ready to be disposed.
  2. Use full chemical names or common names. Chemical formulas or abbreviations are not acceptable.
  3. List all chemical components in the waste container, including water. Long lists may be continued on another label.
  4. Indicate the percent concentration of potentially explosive materials such as picric acid and nitro compounds.
  5. Include any additional hazard information on label.
  6. Attach the tags directly to the bottle or with a string, rubber band, or wire which encircles the container. If you use a sticker, make sure it is securely attached.

22.4.3  Collection and Disposal

Collection days are held approximately every three months. Containers with improper caps, leaks, outside contamination, or improper labeling will not be accepted until these problems have been corrected.

It is very important that hazardous waste be disposed of properly. Improper disposal methods for hazardous chemical waste include the following:

Disposing of Empty Containers

These are questions frequently asked by UTIA personnel. The answer is fairly simple but very important.

EPA regulations stipulate that empty containers must meet the following requirements:

  1. Containers must not contain free liquid or solid residue.
  2. Containers must be triple rinsed.
  3. Product labels must be defaced or removed.
  4. Container lids or caps must be removed.
  5. Punch holes in the bottom of metal containers and plastic jugs before disposing of them in the regular trash.
  6. It is not necessary to break empty glass containers; however, glass containers should be placed in a cardboard box (or other sturdy container) to prevent potential harm to others that handle the waste.

IMPORTANT: Containers that do not meet the requirements mentioned here must be treated as hazardous waste.

22.5  Minimization and Substitution

The cost of commercial waste disposal continues to rise and the amount of waste generated continues to increase. UTIA cannot control disposal costs, but it can reduce the amount of waste generated. The following sections discuss how to minimize waste sources and waste products.

22.5.1  Waste Source Reduction Techniques

Use the following techniques to reduce waste sources:

  1. Use computerized tracking systems to manage purchasing and control inventory.
  2. Maintain current inventory records to prevent overstocking and to monitor the shelf life of remaining chemicals.
  3. Negotiate with suppliers to gain volume discounts, flexible delivery schedules, and delivery of fewer small-sized containers without cost penalties. However, purchase quantities for immediate use only. Do not order large quantities simply to obtain a special unit cost savings.
  4. Obtain compressed gases from vendors who accept return of empty or partially full cylinders.
  5. Include waste generation as a criteria in equipment selection.
  6. Rotate chemical stocks to use chemicals before their shelf-life expires.
  1. Use lab procedures that assure the integrity of chemical quality.
  2. Reduce spills and waste by pre-weighing chemicals for undergraduate use.
  3. Require proper labeling of all secondary containers. Replace all deteriorating labels on primary and secondary containers.
  4. Substitute less hazardous chemicals whenever possible (e.g., biodegradable scintillation cocktails instead of xylene or toluene-based cocktails).
  5. Minimize the use of heavy metals (e.g., silver, chromium, mercury, barium, cadmium, and lead.)
  6. Substitute alcohol or electronic thermal monitors for mercury thermometers.
  7. Use detergents, or enzymatic cleaners to clean laboratory glassware, instead of using solvents.
  8. Minimize solvent waste by recycling or substitution.
  1. Do not mix different types of waste.
  2. Do not put non-hazardous waste, such as a mixture of water, sodium bicarbonate, and Acetic acid, into a waste container of hazardous waste.
  3. Do not combine inorganic heavy metal waste with organic solvents waste.
  4. Segregate halogenated waste solvents from non-halogenated waste solvents.
  5. Segregate waste streams by storing them in separate waste containers.
  6. Store waste containers separately from reagent containers to avoid accidental contamination.
  7. Decontaminate empty containers to make them non-hazardous.
  8. Neutralize dilute acids and bases to make them non-hazardous and suitable for drain disposal.
  9. When possible, redesign experimental protocols so that harmful byproducts are detoxified or reduced.
  10. Recycle chemicals via purification.
  11. Make lab employees accountable for waste when labs are decommissioned.

22.6  Segregation

Segregated waste is safer and easier to dispose of than nonsegregated waste. Mixed waste, for example, must be handled as both radioactive waste and hazardous waste. Each employee who generates waste is personally responsible for the following:

  1. Ensuring that hazardous wastes are accumulated in safe, transportable containers.
  2. Ensuring that hazardous wastes are stored properly to prevent possible exposure.
  3. In addition to the guidelines for waste minimization and substitution, follow these guidelines for waste segregation:
  1. Do not mix non-hazardous waste, such as water, with hazardous waste.

  2. Do not combine inorganic heavy metal waste with organic solvent waste in hazardous waste containers.
  3. Double-bag dry materials contaminated with chemicals (paper, rags, towels, gloves, or kim wipes, etc.) in heavy-duty plastic bags. Do not use biohazard bags. Dispose of these items in the same manner as hazardous waste.
  4. Encapsulate sharps (e.g., needles, razor blades, etc.), then place them in a sturdy container and then in the trash dumpster.

22.7  Special Concerns

Employees who generate hazardous waste must maintain and control their hazardous waste accumulation areas. Special concerns for hazardous waste include the following:

  1. Unneeded chemicals that are to be discarded must be handled and managed as hazardous waste.
  2. Unknown chemical waste will be picked up by Environmental Health & Safety Department. (Departments will be charged for the chemical analysis to determine proper disposal method.)
  3. Gas cylinders are extremely difficult to discard. They should be returned to the manufacturer or distributor whenever possible. Cylinders that cannot be returned should be tagged as hazardous waste as soon as possible.
  4. Photographic chemicals containing silver may not be placed in the sanitary sewer. They must be disposed of as hazardous waste or recycled.  NOTE: Some developing equipment has a filter to capture silver before the photographic effluent enters the drain.

22.8  Ethidium Bromide Disposal

There is no evidence for the carcinogenicity or teratogenicity of this substance in humans,  however it is a powerful mutagen and should be handled as a possible carcinogen and reproductive toxin.  It may present a hazard if it is poured down the drain untreated or placed in the trash.  Ethidium bromide is not regulated as hazardous waste, but is handled as a special waste.  The following are the recommended disposal procedures for ethidium bromide:

22.8.1  Electrophoresis Gels, Contaminated Gloves and Other Equipment

Collect ethidium bromide gels, contaminated gloves and other equipment (DRY wastes) as chemical hazardous waste and bring them to the quarterly waste pick-up (NOTE: The gels must not have running liquid in the bottom of the bag).  One suggested method to prevent personnel cross-contamination while opening and closing the waste container is to use a lined step-on can as the waste receptacle.  When it is time for disposal, place the sealed liner bag in a secondary container such as a bucket, cardboard box, or secondary sturdy bag and put a UT hazardous waste label on the outside of the package.  Handle EtBr waste containers like any other hazardous waste - it must be in a container that is labeled and closed unless you are actively adding waste to the container.


Benefits - the can automatically closes and the lid doesn't get handled, which reduces cross-contamination of other surfaces. Use a thick liner bag and do not put sharps in the container that could puncture the bag.

Bag should be a non-specific color (clear or black). Stomacher bags available thru Fisher reportedly work well.

EtBr waste does not go in red bags or containers, and does not get a biohazard symbol.

NOTE - Ethidium bromide waste that is not mixed with a biological hazard DOES NOT go in red bags or red containers, should not be labeled with a biosafety symbol, and especially should not be treated in an autoclave.  For mixed EtBr and biohazard waste contact the UTIA Safety Officer at 4-1153 or the UT Biosafety Officer at 4-1938 for guidance.

22.8.2  Sharps Contaminated with Ethidium Bromide 

Contaminated needles, syringes, etc. must be discarded into a puncture-proof plastic container (must not be red and must not have a biohazard symbol on it) with a lid that closes.  It shall be marked as ethidium bromide waste.  Do not mix these chemically contaminated sharps in a red biohazard sharps container that may go in the autoclave.  Autoclaving chemical waste creates exposure to the chemicals at they heat and volatilize.  Dispose of the container as chemical hazardous waste at a waste pick-up.

22.8.3  Ethidium Bromide Solutions

1.  Charcoal Filtration

Filtering the aqueous ethidium bromide waste solutions, free of other contaminants, through a bed of activated charcoal is a relatively simple and effective method for removal of ethidium bromide.  The  filtrate may then be poured down the drain.

There are two simple kits available for charcoal filtration:


a.  Funnel Kit

Schleicher and Schuell supply a commercial  filter funnel kit that uses a packaged charcoal disk that is graduated for easily tracking the amount of aqueous solution calculated for a fixed quantities of ethidium bromide residue.  This product is recommended for dilute solutions such as electrophoresis gel staining buffer (0.5X TBE/0.5 ug/ml EtBr) and is particularly useful for labs that generate large amounts of solutions at a time.  The kit is available through Fisher Scientific, Schleicher and Schuell, or VWR.


Filter the ethidium bromide solution through the charcoal filter.

Pour filtrate down the drain.

Place charcoal filter in a sealed bag (e.g., zip-lock) and place with EtBr gels for hazardous waste disposal.


b.  The Green Bag

Another simple charcoal filtration method is the Green Bag, manufactured by BIO 101.  The Green BagŪ Kit allows rapid and trouble-free concentration of ethidium bromide from large volumes of solutions into a small "tea" bag containing activated carbon which is then conveniently disposed along with other solid hazardous wastes. One kit has the capacity to remove 500 mg of ethidium bromide from solutions (10mg EtBr per "tea bag").

2.  Chemical Neutralization

Solutions containing ethidium bromide can be deactivated, neutralized and poured down the drain with copious amounts of water.  Deactivation may be confirmed using UV light to detect fluorescence.  There are three recognized methods for deactivation:


a.  Armour Method

This is the simplest method, but is somewhat controversial.  One study found traces of mutagenic reaction mixtures using this method. (Lunn, G. and E. Sansone, Analytical Biochemistry, vol. 162, pp. 453-458, 1987)

b.  Lunn and Sansone Method

For each 100 ml of ethidium bromide solution:

c.  Quillardet and Hoffnung Method

This method uses 0.5 M potassium permanganate and 2.5 M hydrochloric acid.  Since chlorine gas may be released in significant concentration, EHS does not recommend using this method.


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