Since the beginning of metal refining around 5,000 years ago, people have been unawarely inhaling, ingesting and absorption tiny amounts of lead byproducts into our bodies.
An analysis of human remains from ancient Rome has revealed that lead pollution is closely linked to our history of mining, and smelting.
Researchers have found that the effects of global lead production can be seen in the bones of central Italian people who are buried there. Even those who were not involved in local mining and smelting showed signs of lead particles in their bodies.
The pollutant seems to have spread quickly from the beginning. Romans only had to breathe in the pollutant, drink the water and eat local foods to see the heavy metal build up in their livers and kidneys.
Yigal Erels, geologist at the Hebrew University of Jerusalem, Israel, says that "this documentation of lead contamination throughout human history suggests that, remarkably," much of the expected dynamics in lead production can be replicated in human exposure.
Simply put, lead is more toxic than we think. This can have a very toxic effect."
Lead can poison nearly every system of the body. Even low levels of lead can cause harm, as it accumulates over time, potentially leading to neurocognitive problems, organ damage and reproductive problems.
This was something that the Romans knew, but they ignored silver, gold, and lead. They even built their own plumbing out of lead and delivered the heavy metal directly to their population, despite some miners becoming insane or dying from exposure.
However, the rise in lead production in Roman society was only possible when coin production started around 2,500 years ago.
This is when lead poisoning really began to spread among the people, according to careful analysis of soil from lakes and ice from glaciers. This timeline is also evident in ancient human remains from Italy.
Researchers have discovered a rise of lead pollution in Italy, based on the analysis of bones from 132 people who were buried between 12,000 BCE & the 17th Century.
The ratio of calcium to lead in bones showed an increase when Romans began mining lead for smelting. The concentration of lead in human remains increased dramatically when coins were first produced around 2,500 years ago.
Research has shown that lead production rose by fourfold between the dawn of metalurgisty and the peak of the Roman Empire. The current study revealed that the human bone concentrations of lead increased by 4,000 times during the same period.
Lead rates began to decline only in the late Medieval Period. However, by a thousand years before that, lead pollution had been on the rise thanks to silver mining in Germany, and the discovery of the New World’s riches.
The rise in lead pollution in Italy this time around was not as dramatic. This could be because lead production has shifted from Europe to more remote regions of the globe.
Researchers still found evidence that lead production had increased in the world during the last millennium.
These are some of the most important lessons from history. Recent years have seen a slight decline in lead production, but there is a growing demand for heavy metals.
Some estimates project that there will be an increase of more than 1,000% in demand for cobalt, lead, and nickel by 2050. This is due to increased demand for electronics, solar panels and wind turbines, which help reduce runaway climate change.
The authors conclude that this raises concern about the possibility that elevated levels of toxic metals, including lead, in electronic devices and in the transition to low carbon energy production could soon reflect in higher concentrations in the human body. This is primarily in those who are not fortunate enough live in areas that are regulated and monitored.
For example, in 2017, the Institute for Health Metrics and Evaluation estimated that lead exposure caused more than 1,000,000 deaths and 25 million years of unhealthy life loss around the globe. The most vulnerable countries, with the greatest health risks, were those of low- and middle income.
These nations have children that are particularly vulnerable to heavy metals. Research shows that young people absorb up to four to five times the amount of lead they ingest than adults. This can cause severe developmental effects.
A third of all children in the world have unsafe levels of lead in their blood. The pollutant will likely accumulate in the next generation if the production of this heavy metal continues to increase.
Erel warns that the close relationship between lead production and human lead concentrations in the past suggests that we will continue to suffer the harmful health effects of toxic metals contamination.
It is a fact that history has shown us.
The study was published by Environmental Science and Technology.
