Scientists sound alarm over growing risk of metal pollution due to manufacturing industries

Scientists have warned that the legacy of the industrialisation of our world has a direct impact on what happens inside our bodies, even if we don’t think we are being directly exposed to pollutants.

A new study by researchers at The Hebrew University of Jerusalem has revealed how toxic lead exposure in human bones carefully tracks lead production over thousands of years.

Through examining human remains from a burial ground in central Italy, which has been in use for 12,000 years, the scientists found that as worldwide lead production began and increased, so too did the rate of lead absorption in people living at the time – even in those “not remotely involved in lead production”, but who were simply breathing the air around them.

The research team said their study into the toxic effects of metal pollution has far-reaching implications for public health, given the forecasted increase in production of lead and other metals to keep up with manufacturing demands for items including electronic devices, batteries, solar panels and wind turbines.

While we tend to associate lead poisoning with old lead-based paints and lead water pipes, it has its own rich history stretching back several millennia.

A big boost in lead production began 2,500 years ago with the striking of coinage, reaching its peak during the Roman period before declining during the Dark Ages.

During the Middle Ages, lead production was on the rise again, prompted by silver mining in Germany, then in the Americas, and finally to meet the demands of the industrial revolution.

The researchers said that while increases in lead production rates are well documented in environmental archives, such as glaciers and sediments from lakes, lead concentrations in human bones and teeth have not previously been used to inform the narrative around humans’ relationship with lead, until now.

The scientists analysed bone fragments from 130 people who lived in Rome, from as early as 12,000 years ago – well before the advent of metal production – until the 17th century.  By analysing the elemental composition found in their bones, the researchers were able to track the level of lead pollution over time, and showed that it closely followed the rate of worldwide lead production.

Professor Yigal Erel, the lead author of the research, says: “This documentation of lead pollution throughout human history indicates that, remarkably, much of the estimated dynamics in lead production is replicated in human exposure. Thus, lead pollution in humans has closely followed their rates of lead production.

“Simply put, the more lead we produce, the more people are likely to be absorbing it into their bodies. This has a highly toxic effect.”

The research team warn that increasing rates of industrialisation risk exposing future generations to the impacts of lead.

“Studies have shown that toxic lead exposure in people, especially in children, takes place through diet, air pollution and urban soil resuspension (in which particulate deposits from the ground are transferred into the atmosphere as a result of wind, construction and other activities).”

They also note the “ever-mounting demand for metals in the manufacturing of electronic devices”.

Professor Erel says: “The close relationship between lead production rates and lead concentrations in humans in the past suggests that without proper regulation we will continue to experience the damaging health impacts of toxic metals contamination.”

While those most directly affected by these dangers are people with the highest exposure to lead, such as miners and employees in recycling facilities, lead can be found throughout our daily lives in the form of batteries and the new generation of solar panels that deteriorate over time and release their toxicity into the air we breathe and the soil from which we grow our crops.

“Any expanded use of metals should go hand in hand with industrial hygiene, ideally safe metal recycling and increased environmental and toxicological consideration in the selection of metals for industrial use,” says Professor Erel.

The research is published in the journal Environmental Science and Technology.