Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity

McConnell, J. et al. (2018), “Lead pollution recorded in Greenland ice indicates European emissions tracked plagues, wars, and imperial expansion during antiquity,” Proceedings of the National Academy of Sciences 115: pp. 5726-31. 

This article links levels of lead pollution found in ice cores taken from Greenland to Ancient mining activities, particularly tracking their significant rise and fall in the Roman period. There is a particular focus on the intensive mining activity in the Iberian peninsula under first Carthaginian and then Roman control. An interesting theme which emerges out of the research is how rises and falls in lead pollution levels can be related to outbreaks of war. For example, a notable decrease in pollution levels coincides with the outbreak of the first Punic War (261-241 BCE), which is suggested to be a result of the mining workforce being redirected towards the war effort, but which later increases again as the Carthaginians increased its silver mining to pay for mercenaries. The relative peace of the first century CE thus allowed for ‘the highest lead emissions in antiquity’ (p. 5727). The abrupt decrease in pollution levels which occurred in the second century CE is linked to the outbreak of the Antonine Plague (165-193 CE), with the following outbreak of the Plague of Cyprian (249-270 CE) preventing the mining industry’s recovery to the levels of productivity seen in the first century CE. What is particularly striking about the evidence revealed by the ice cores (and supported by previous samples taken from peat bogs), is how environmental scientific methods can aid in our understanding of the effects of war and pandemic on ancient industries and economies. The duration of each rise and fall in lead emissions reveals how long it for ancient mining activities to recover from catastrophic events and how successfully they did so.

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