In the beginning of the 1920s, the leading American oil and automobile industry add lead to gasoline to get a more efficient fuel. At that time, lead was already a known poison, harmful to the nervous system - especially to children. Quickly, lead outcompetes other harmless additives, and the profit of the oil industry is huge in the decades to come. But hundred thousands tons of lead are spread around the world and cause injuries on millions of people - among others in lost IQ. Lead from gasoline has, literally, made a lot of us a bit more dim.