A study from Tel Aviv University shows ancient copper mining had minimal environmental impact, challenging previous assumptions about pollution during King Solomon’s era.

Bible, King Solomon’s Mines were a treasure trove of wealth and prosperity, said to supply the ancient world with vast quantities of copper. For centuries, this legendary site has captivated historians and archaeologists alike, as it was believed to be central to the flourishing kingdom of Solomon. However, a groundbreaking study by researchers from Tel Aviv University is now challenging conventional beliefs about the impact of this ancient copper industry.

New Study Challenges Long-Held Assumptions About King Solomon’s Kingdom

Their findings suggest that not only did it have minimal effect on workers’ health, but it also posed no significant risks to modern residents living near the site. Through detailed geochemical surveys of copper production sites in the Timna Valley, dating back to the 10th century BCE, the researchers have revealed that copper production caused limited and localized environmental pollution, with no evidence of harm to the health of past or present inhabitants. This research adds a surprising new layer of understanding to the environmental legacy of one of history’s most enigmatic industries.
The study was led by Prof. Erez Ben-Yosef, Dr. Omri Yagel, Willy Ondricek, and Dr. Aaron Greener from the Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures, Chaim Rosenberg School of Jewish Studies and Archaeology, Tel Aviv University. The paper was published in the prestigious journal Scientific Reports by Nature.

Health Impact of Ancient Copper Production Sites

“We inspected two major copper production sites in the Timna Valley, one from the Iron Age and King Solomon’s era and another nearby that is about 1,500 years older,” says Prof. Erez Ben-Yosef. “Our study was very extensive. We took hundreds of soil samples from both sites for chemical analyses, creating high-resolution maps of heavy metal presence in the region. We found that pollution levels at the Timna copper mining sites are extremely low and confined to the locations of the ancient smelting furnaces. For instance, the concentration of lead — the primary pollutant in metal industries — drops to less than 200 parts per million just a few meters from the furnace. By comparison, the U.S. Environmental Protection Agency defines industrial areas as safe for workers at 1,200 parts per million and residential areas as safe for children at 200 parts per million.”

The new study contradicts a series of papers published since the 1990s about pollution caused allegedly by the ancient copper industry. “We demonstrate that this is not true. Pollution in Timna is very restricted spatially, and it’s likely that only those working directly at the furnace suffered from inhaling toxic fumes, while just a short distance away, the soil is entirely safe. Moreover, the match we found between the spatial distribution of copper and lead concentrations in the soil further indicates that the metals are ‘trapped’ in slag and other industrial waste – which keeps them from leaching into the soil and affecting plants or humans.

Our findings align with several recent studies from the Wadi Faynan region in Jordan, which also point to very low levels of pollution. Timna and Faynan are ideal sites for this type of research because they have not been disturbed by modern mining, as happened in Cyprus for example, and thanks to their dry climates the metals in the soil are not washed away. In Faynan, a team led by Prof. Yigal Erel of the Hebrew University examined 36 skeletons of people who lived at the mining site during the Iron Age, and only three showed any trace of pollution in their teeth. The rest were completely clean. We now present a similar picture for Timna.”

In addition to the geochemical survey, the TAU archaeologists also conducted a comprehensive review of existing literature, pointing out that hypotheses about global pollution during the pre-Roman period lack solid evidence.

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“There was a trend in the 1990s, which presented ancient copper production as the first instance of industrial pollution,” explains Dr. Omri Yagel, a leading researcher in the current study. “Such statements grab headlines and attract research grants, but they unnecessarily project modern pollution problems onto the past. Moreover, the research literature tends to use the term ‘pollution’ to describe any trace of ancient metallurgical activity, and this has led to the mistaken assumption that metal industries were harmful to humans from their earliest beginnings — which is patently untrue.

Even when metal production was large-scale, becoming integral to human civilization, it was the toxic lead industry that caused global pollution, not necessarily other metals. A 1990s study argued that traces of copper found in Greenland ice cores had traveled through the atmosphere from sites like Timna. This claim, however, has not been corroborated by any subsequent study. As researchers confronting the severe environmental challenges of our time, such as climate change, we often tend to search for similar problems in the past or assume that environmental harm has been an inevitable consequence of human activity since the agricultural revolution. However, we must be cautious. While we might label a few pieces of slag on the ground as ‘pollution,’ we should not confuse this localized waste with regional or global environmental pollution.”

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Reference:

1. Pre-roman copper industry had no polluting impact on the global environment – (https://www.nature.com/articles/s41598-024-80939-5)

Source-Eurekalert