Waste Minimization

Waste minimization techniques can play a vital role in reducing the amount of hazardous waste generated annually at the University. Waste generators are encouraged to actively investigate waste minimization techniques and incorporate these techniques as an integral part of the teaching and research process.

A few suggestions for minimizing waste generation are listed below. Additional ideas are always welcomed, and may be forwarded to the Manager, Environmental Protection Services at 416.978.7000 or e-mail eps.hazdisposal@utoronto.ca.


  • Purchase hazardous materials in the smallest quantities needed.  Stockpiling hazardous materials rarely works, and eventually results in excessive costs to the researcher and additional disposal costs to the University.
  • Donations in bulk (e.g., entire industrial laboratory inventories) to the University can result in receiving unwanted hazardous materials and therefore, costly disposal problems. Accept only those hazardous materials that will be required by the laboratory within a year. Due to regulatory requirements, donations involving radioactive or biological agents, will require prior approval from the Office of Environmental Health and Safety.

Process modification

  • Examine experimental protocols to, if possible, eliminate materials that would result in the generation of hazardous wastes.
  • Review experimental procedures to see if quantities of hazardous materials can be reduced (e.g., micro methods).

Product substitution

Evaluate experimental procedures to see if a less hazardous material may be used e.g.,

  • toluene substituted for benzene
  • a metal oven thermometer instead of a mercury thermometer in ovens
  • alcohol thermometers for mercury thermometers
  • phosphorus-33 for phosphorus-32
  • non radioactive DNA labelling for radioactive DNA labelling

Good Laboratory practice

  • Hazardous waste disposal planning must be part of all experimental protocols.
  • Record the date on containers when they are received so that older ones will be used first. This may eliminate time sensitive materials being unnecessarily directed to disposal.
  • Avoid storing excess hazardous material.
  • Good housekeeping and tracking of hazardous material inventory can prevent waste and duplication.
  • Ensure that all samples and containers are properly identified with the appropriate scientific (and not “coded”) name. Analysis of unidentified containers is costly and disposal of these containers is illegal under WHMIS legislation.
  • Do not mix hazardous with nonhazardous waste products. This contaminates the waste stream and unnecessarily adds to the cost of disposal.
  • On termination of a research project ensure all hazardous materials and containers are labelled and those no longer required are disposed.
  • For those hazardous materials stored in “shared facilities” such as cold rooms, etc., the research director, Principal Investigator or researcher should take responsibility for the disposal of these materials after a research project has been completed.