Widespread use of metal caused estimated 2- to 3-point drop in IQ for nearly 180 years of Pax Romana

Apart from sanitation, medicines, education, wine, public order, irrigation, roads, the fresh water system and public health, what did the Romans ever do for us? – asks an exasperated Reg in Monty Python’s Life of Brian.

One answer, according to a new study, is widespread cognitive decline across Europe, courtesy of the vast quantities of lead pollution churned out by the booming metals industry that shaped the empire.