The Dundas Star News provides a good primer on pesticide law in Canada:

Known by its acronym WHMIS, the program also sets rules for warning labels of chemicals and establishes a worker’s right to know details of the chemicals they use.

But the federal government, through a division of Health Canada, and the Ontario Ministry of Labour both leave Ontario pesticide manufacturers out of the Workplace Hazardous Material Information System, because the province has its own pesticide legislation.

But Ontario’s Pesticide Act only deals with the sale and application of pesticides, and specifically exempts manufacturers of the substances from its requirements, according to the Ministry of the Environment.

The full article available from the Dundas Star News.