Ancient teeth reveal when Britain’s medieval lead boom began and who paid the price

The hills of the Derbyshire Peak District produced more lead than anywhere else in western Europe during the Middle Ages, yet the industrial landscape that made this possible has long been hidden from archaeologists. Centuries of later mining, and the repeated re-smelting of Roman and medieval lead waste between the sixteenth and nineteenth centuries, destroyed or recycled almost every trace of the earliest workings. Now a research team led by the University of Nottingham, working with the British Geological Survey, the University of Sheffield, York Archaeology and the Castleton Historical Society, has recovered the missing chronology from an archive that no smelter could touch: the teeth of the people who lived alongside the industry. By measuring lead locked into tooth enamel, the team has established that lead mining and smelting restarted in the region by the middle of the seventh century, within a century of the end of Roman Britain, and has reconstructed how that industry shaped the bodies and lives of local communities for the next eight hundred years.

The method rests on a simple but powerful property of human biology. Tooth enamel forms during childhood and, unlike bone, is never remodelled or replaced throughout life. Any lead absorbed by a child while the enamel is mineralising is permanently sealed into its crystalline structure, creating a chemical record of the environment in which that person grew up. Because lead is a toxic metal that damages the nervous, renal and reproductive systems, and because medieval mining and smelting generated multiple routes of exposure through contaminated dust, fumes and ore-handling materials, the enamel of buried individuals preserves a direct measure of industrial pollution at the level of the household rather than the landscape. By measuring lead concentrations in enamel from people buried between roughly 650 and 1500, the researchers could reconstruct childhood exposure across the entire span of the medieval industry, from its obscure beginnings to its documented medieval peak.

The chronological breakthrough came from comparing the Peak District cemeteries with populations from across Britain, spanning the Neolithic through to the Industrial Revolution. The analysis showed that children raised in the Derbyshire mining communities of the seventh century carried lead burdens equal to, or greater than, those measured in children living in the industrialised cities of roughly 1750 to 1850. This is the first study to analyse lead contamination in the bodies of people who actually mined and smelted lead in western Europe’s largest medieval lead-producing region, and it provides the first absolute evidence that post-Roman production there was established by the mid-seventh century AD. By the mid-eighth century, the scale of operations had grown enough to contaminate the wider environment around mining centres such as Castleton, embedding the industry in the regional landscape within a few generations of its revival.

Christopher Loveluck, Professor of Medieval European Archaeology at the University of Nottingham’s Department of Classics and Archaeology, said the team was delighted to have finally confirmed definitively the date by which the early medieval lead industry was established in the Peak District, by the mid-seventh century AD, through evidence provided by the people themselves. That confirmation, he noted, supplies the foundations of what became western Europe’s largest lead-producing region between the late twelfth and sixteenth centuries. The significance is difficult to overstate. Lead was an essential medieval commodity, used for roofing, piping, coinage and the manufacture of vessels, and the Peak District’s ores underpinned economies and politics far beyond central England. Until now, however, historians and archaeologists could only infer when production resumed after the Roman withdrawal, because the physical evidence had been systematically erased by later exploitation of the same deposits.

Perhaps the most striking finding concerns inequality. Exposure to the industry’s pollution was not distributed evenly across society. Individuals buried with high-status grave goods, including weapons, generally carried much lower lead concentrations in their enamel than those from less richly furnished burials. The pattern suggests that elites may have controlled or benefited from lead production while lower-status households were more directly involved in the physically dangerous work of processing ore and smelting, exposing children within those communities to far higher levels of contamination. In chemical terms, the archaeology of status and the toxicology of childhood align: the richer the grave, the cleaner the enamel. This offers a rare, biologically grounded view of how the profits and hazards of a medieval extractive industry were divided between those who directed it and those who laboured within it.

The study also highlights the potential vulnerability of women in these mining communities. Three women analysed in the research died between the ages of around seventeen and twenty-five, and all showed elevated childhood lead exposure. While the relationship between childhood lead burden and premature death remains complex, the results suggest a possible association between high lead levels and increased health risks, one that may have been particularly significant during pregnancy, when lead stored in the skeleton can be released back into the bloodstream. Dr Anna Bloxam, Co-Director of the Castleton excavations, said that modern studies show lead can have profoundly harmful effects on the health and development of children, and that there is no safe level of exposure. She noted that all the individuals in the study survived into adulthood, but were exposed while young and growing, and that the skeletons show most of the men studied lived until middle or old age whereas the women primarily died much earlier, in young adulthood. In her view, girls and boys alike were raised in dangerously polluted home environments, an exposure likely to have caused negative health effects in life and perhaps contributed to higher rates of premature death among women of child-bearing age.

The enamel record also tracks the industry’s long arc of expansion. Lead exposure remained high throughout the medieval period and reached its greatest levels during the late twelfth and early thirteenth centuries, precisely when historical records show that Peak District lead production attained its medieval height and when environmental archives across Europe register rising atmospheric lead pollution. The human data dovetail with earlier studies of Alpine ice cores and of sediment cores from river channels, lakes and peat bogs, which identified a marked rise in atmospheric lead around 1200 attributed especially to British production. What the new research adds is the direct link between those environmental signals and the people living and working within one of Europe’s major lead-producing landscapes. The pollution recorded in distant glaciers can now be tied, chemically and chronologically, to the children who grew up breathing the fumes of the furnaces that caused it.

Isotopic analysis of the same teeth added an unexpected social finding: the mining communities of the Peak District were remarkably stable. Most individuals studied had grown up locally, indicating that the specialised knowledge of mining and smelting was passed down through generations of local families rather than sustained by large numbers of incoming workers. This intergenerational transmission of craft expertise helps explain both the durability of the industry and the persistence of its health burden, since the same households that held the technical skills also absorbed the toxic consequences across childhood after childhood. The research builds on decades of earlier archaeological investigation in the region, including work by Colin Merrony at the University of Sheffield, who identified and excavated key medieval burial sites. The combined samples came from three cemetery populations: Wigber Low in the Derbyshire White Peak, dating to the seventh century; Joule Yard at Castleton, dating from the seventh to eleventh centuries; and Spital Field at Castleton, dating from the twelfth to fifteenth centuries, together providing a unique record of communities living through the revival and expansion of medieval lead production.

Merrony said that recent excavations in Castleton have provided a great deal of new information about the people living in the Hope Valley during the medieval period, revealing more about the size of the population and showing from the archaeological evidence that these working communities were involved in industries requiring hard physical labour. The new study, he said, has enabled researchers for the first time to look beyond that broader understanding and see more deeply into the profound impact lead production had on individuals and the communities they lived in. By bringing together archaeology, history, chemistry and environmental science, the research shows how one of Britain’s most significant industrial landscapes developed, and how its effects can still be detected more than a millennium later. The findings relate to medieval mining and smelting between the seventh and fifteenth centuries and do not reflect modern environmental conditions; the legacy of historic mining in the Peak District is now well understood and carefully monitored, with land management, conservation and environmental regulation minimising any risks from former mining activity. The results will form part of the developing medieval archaeological research agenda for the Peak District National Park, funded by Historic England, and will be shared with the public through a temporary display in the region over autumn and winter 2026-27, showcasing the findings alongside archaeological discoveries from the Castleton excavations. The research was funded and supported by the University of Nottingham, the Peak District National Park Authority, Castleton Historical Society, the University of Sheffield, Sheffield Museums and Historic England, and is published in the journal Antiquity.

Subject of Research: Medieval lead mining and smelting in the Derbyshire Peak District reconstructed through lead exposure in human tooth enamel

Article Title: New research traces the origins and human impact of Britain’s largest medieval lead industry through ancient teeth

Article References: New research traces the origins and human impact of Britain’s largest medieval lead industry through ancient teeth. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Peak District, lead mining, medieval archaeology, tooth enamel, lead exposure, Castleton, Antiquity, University of Nottingham, seventh century, industrial pollution, isotopic analysis, public health