Dozens of chemicals that are banned in the European Union for their suspected links to cancer and neurological diseases are widely available across Africa—and made by European manufacturers. The region imported 438,000 tons of pesticides and herbicides in 2020, two-thirds more than in 2018. More than half of such chemicals used in Nigeria are considered highly hazardous, and at least 40% of those can’t be sold in Europe, according to the nonprofit Alliance for Action on Pesticides in Nigeria.