evidence: A pesticide called Monitor is used to grow potatoes for McDonald’s french fries. [...] Several social media posts claim that a pesticide called Monitor is used to grow potatoes for McDonald’s french fries. But this is not true in the UK, EU and US at least, where the pesticide has not been approved for use for years. [...] In his speech, which is quoted in many of the posts, Mr Pollan said McDonald’s insists that all its fries are made from Russet Burbank potatoes. He went on to claim that only a pesticide called Monitor can protect these potatoes from "net necrosis", which creates the brown blemishing sometimes seen on the vegetables and is a symptom of a viral infection spread by aphids (insects that suck the sap of plants).