Medieval bear’s teeth prove historic lead pollution

Palaeontologists have found high levels of lead in the teeth of a bear that lived around 1000 years ago. Humans have processed lead and other heavy metals for millennia. In the middle ages it had a wide range of uses including in coins, roofing, pipelines and pottery glazes. There is a growing realisation that early mining and smelting practices affected ecosystems by releasing particles into the atmosphere, contaminating water and accumulating in the food chain. Use this story and the downloadable summary slide to provide context for 14–16 lessons on extraction of metals, pollution and chemical analysis of trace elements.