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Herbicide exposure (2,4,5-T) update


In 2011, newspaper reports surfaced of herbicide spraying from the late 1940s through the 1970s in Ontario. The articles featured workers living with conditions and diseases they believed were caused by exposure to herbicides at work in Ontario.

WSIB takes action

The WSIB moved quickly to create a dedicated team to respond to calls and questions from workers and the public.  A special adjudication team was also put in place to handle claims arising out of potential exposure to the herbicide 2,4,5-Trichlorophenoxyacetic acid (2,4,5-T) and its contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD).

Gathering information and expertise

Since that time, we have gathered information from workers, their employers, and their doctors.  We have considered a range of medical and scientific evidence to inform our decision-making. This included the best available information from internationally-recognized authorities, such as the U.S. Institute of Medicine (IOM). The report from the Ontario Independent Fact-Finding Panel on Herbicide 2,4,5-T, released in June 2013, was another key source of information, providing details about exposure to 2,4,5-T and its contaminant, TCDD.

Fair and impartial decision-making

The WSIB adjudicates claims fairly and impartially using all of the available information to determine entitlement to benefits.  The adjudication of occupational disease cases is complex, particularly when gathering employment and medical information going back decades.

The WSIB is moving forward with decisions in claims from workers who believe that their current medical conditions may be related to workplace exposure to 2,4,5-T and its contaminant, TCDD.  In each case, the evidence is weighed carefully to arrive at decisions that reflect the best available information and expertise about exposure to 2,4,5-T and TCDD, and its relation to health outcomes.

Our adjudicative approach ensures that every worker’s case is considered thoroughly and fairly. 

The WSIB’s main number (1-800-387-0750) features live answer Monday to Friday from 7:30 a.m. to 5:00 p.m.

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