Many farmers say they cannot do without glyphosate. The pesticide is very effective and therefore the most used weed killer in the world. But how safe is glyphosate? Scientists who examined the pesticide on behalf of the World Health Organization concluded that it is probably carcinogenic to humans. However, its use has recently been permitted again for 10 years by the European and national pesticide authorities. How is it possible that different independent scientists come to a different conclusion than the admission authorities? Zembla is investigating the approval of the poison.