Dow AgroSciences filed a $2 million notice of action against the Canadian federal government in August 2008. The company argues that Quebec is basing the ban on non-scientific criteria, which breaches provisions under Chapter 11 of NAFTA.

The chemical has been used for decades in dozens of countries. Health Canada ruled this year that 2,4-D could be used safely according to label directions but studies have linked the chemical to cancer, neurological impairment and reproductive problems.

Quebec and Ontario have taken steps to introduce more stringent standards on cosmetic pesticides. In June, Ontario passed legislation to ban more than 300 pesticide products. In April of 2006 Quebec pulled more than 200 products from store shelves.