5.4 Mixed Waste

Occasionally, laboratory waste may contain or be contaminated with a combination or mixture of biological, chemical and radioactive materials. This type of waste poses a challenge for disposal. Inactivation and disposal will be considered on a case-by-case basis, as required.

As a general rule for waste containing combinations of hazardous chemical, radioactive and biological agents, the biological hazard should be inactivated first
  • Steam sterilization is generally not recommended for waste containing combinations of significant quantities of hazardous chemical, radioactive and biological agents.
  • Refer to disinfection procedures in Section 5.1. After disinfection, the remaining waste can be disposed of as chemical or radioactive waste.
  • Waste containing or contaminated with chemical and radioactive materials, will be treated as radioactive waste. Refer to Section 5.3.


Cytotoxic waste is a by-product of cytotoxic drug therapy and can also be generated through research.  Cytotoxicity is the quality of being toxic to cells. Cytotoxic waste typically includes all drug administering equipment as well as gowns, body fluids/waste from patient and any leftover product.  This type of waste must be collected in the red hazardous waste pails and labelled as ‘Cytotoxic Waste’ then send off through our approved contractor for incineration. Please contact Environmental Protection Services at (416) 946-3473 for supplies and pick ups.
For further information about procedures for waste containing hazardous chemicals or radioisotopes, contact Environmental Protection Services, at 416.978.7000 or e-mail eps.hazdisposal@utoronto.ca