Health Canada is advising Canadians to not use malathion products purchased before June 2016

Examine your product label. If the label does not display an expiry date, and if you purchased the product before June 2016, or if you are unsure of when you purchased it, do not use it. Make sure any products containing malathion are stored in a cool (around 20-23°C), dry and well-ventilated place, away from seed, fertilizer or other pesticides.