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Fact-Finding Panel Releases 2,4,5-T Report

Archived News Release

Fact-Finding Panel Releases 2,4,5-T Report

The Ontario Independent Fact-Finding Panel on Herbicide 2,4,5-T has released its report. The report, and the 4,747 government records provided to the panel, are publicly available at: ontario.ca/245T.

In 2011, Ontario established the panel to determine where, when and how 2,4,5-T (2,4,5-Trichlorophenoxyacetic acid) herbicide was used in the province in the 1950s, 1960s and 1970s for weed or brush control by government ministries and agencies, and whether exposure may have potential health impacts.

The Ontario government established a dedicated phone line for the public at 1-888-338-3364 as well as a dedicated Workplace Safety and Insurance Board (WSIB) line at 1-800-387-0750 for Ontario workers who have concerns about possible workplace exposure.

Quick Facts

  • Ontario is the first Canadian jurisdiction to launch a government-wide review of the use of 2,4,5-T.
  • Ontario took early action and suspended the use of 2,4,5-T in 1979 and banned it in 1980. The federal government deregistered the product in 1985.
  • The fact-finding panel was led by Dr. Leonard Ritter, executive director of the Canadian Network of Toxicology Centres and Professor Emeritus of Toxicology at the University of Guelph.
  • The WSIB is reviewing the report as part of its work to adjudicate claims from workers who believe that their medical conditions were caused by workplace exposure to herbicides, like 2,4,5-T.

Background Information

Additional Resources


“I am pleased to present the panel’s report to the Ontario government. In addition to the expertise that each panel member brought to the team, the findings are based on two years of research that examined more than 4,700 Ontario government records, the development of exposure models and a review of health-related literature from jurisdictions across the world. I am confident that these findings will provide a solid foundation to help us better understand the effects of 2,4,5-T usage by the Ontario government. I applaud the Ontario government for being the first jurisdiction in Canada to undertake such a comprehensive, science-based study.”

Dr. Leonard Ritter

Chair, Ontario Independent Fact-Finding Panel on Herbicide 2,4,5-T

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