Disposal of Select Agents & Other Biologically-Derived Toxins

Biologically-derived toxins and infectious material cannot be sent to the hazardous waste facility (Fay Thompson Center for Environmental Management) for disposal.

Regulated Select Agent Laboratories

Disposal of select agents by registered select agent laboratories requires prior approval from DEHS and CDC. If you wish to dispose of a select agent toxin, contact a DEHS biosafety officer at 612-626-6002 to initiate the approval process.

Exempt Quantity Select Agent Laboratories and Other Biologically-Derived Toxin Users

Although autoclaving or treatment with 5% sodium hypochlorite is sufficient to inactivate many toxins, there are exceptions. In order to assure consistent and effective inactivation of all toxins, follow the procedures below. Report toxin inactivations as indicated on the bottom of the Toxin Inactivation Report (Word doc) so an up-to-date inventory can be maintained by DEHS.

Procedures for the Inactivation of Biologically-Derived Toxins

Staff involved with the inactivation of biological toxins must wear a lab coat, gloves, and a face shield. A face shield is not required if a biological safety cabinet is used as the work area. Note: at least two persons are required to be present during the inactivation process. Staff involved with the inactivation process must have had training on the handling of hazardous materials.

A spray bottle of 2N sodium hydroxide should be available in the event a spill occurs. Spray the work surface spill area with this solution and allow a contact time of one hour. Then spray the work surface with an acid to neutralize the NaOH until the final pH is between 5 and 10. Wipe the work surface with towels and then dispose of the towels in a biohazard container.

For small vials or containers of dry biological toxins:

• Prepare 25 milliliters (or quantity sufficient to cover container) of 2N NaOH in a plastic beaker. Label the beaker as to its content.
• Open the vial or container in a biological safety cabinet and place it into the NaOH solution.
• Use a glass rod or a long forceps to tilt the vial/container so that the solution completely fills the vial/container.
• Allow the vial/container to stand in the solution for at least 1 hour. Place the beaker in a safe area (i.e. fume-hood).
• Remove the vial/container from the solution and rinse with water. Dispose of the vial/container in the normal waste.
• Neutralize the NaOH solution with acid until the pH is between 5 and 10.
• If the toxin was not in a hazardous chemical mixture, the inactivated toxin can be sewered. If the toxin was in a hazardous chemical solution, dispose of it according to hazardous waste guidelines. Do not list the inactivated toxin on the manifest.

For solutions containing biological toxins:

• Estimate the volume of liquid.
• Add sufficient NaOH to make a 2N NaOH solution. Beware: make sure that the chemical(s) in the original solution are compatible with NaOH.
• Allow the solution to stand for at least 1 hour.
• If the material is being disposed of as chemical waste, fill out the correct form excluding the now inactivated biological toxin (i.e. the toxin should not be listed).
• If the solution is compatible with sanitary sewer disposal, neutralize it with acid until the pH is between 5 and 10.