In the tooth enamel of people who lived in the Peak District more than a thousand years ago, a precise record has been preserved of how the revival of the lead industry after the fall of Rome poisoned entire generations.
Researchers from the University of Nottingham analysed remains from three cemeteries — Wigber Low of the 7th century and two in Castleton, spanning the period from the 7th to the 15th century. Enamel forms in childhood and does not change throughout life, so it preserves information about environmental lead pollution.
Already by the middle of the 7th century, the concentration of lead in the teeth of local children reached or exceeded the levels characteristic of industrial cities of the 18th–19th centuries. The background level should not exceed 0,5 ppm, yet in most of the people studied it ranged from 15 to 40 ppm, and in four individuals it was more than 40 ppm.
Lead production, resumed by the middle of the 7th century, had polluted the surroundings of Castleton by the middle of the 8th century. The peak of pollution came at the end of the 12th and the beginning of the 13th century, when the Peak District became the largest supplier of lead in Western Europe.
Social inequality manifested itself especially vividly: people buried with swords and expensive jewellery had significantly lower lead concentrations. The poor, who were engaged in mining and smelting ore, accumulated the toxin in dangerous quantities already in childhood.
Three young women aged 17–25 years, whose teeth showed extremely high doses, died prematurely. Although a direct link to poisoning has not been proven, lead damages the nervous, renal and reproductive systems, and during pregnancy it can re-enter the bloodstream.
Most of the people studied grew up in the area, meaning that mining skills were passed down from generation to generation within local families. The skills that fed them also poisoned those who practised them.
The study, published in the journal Antiquity, shows how the economic rise of medieval England left a deep mark on the bodies of ordinary people, and modern methods make it possible to read that mark centuries later.
