Earliest evidence of pollution by heavy metals in archaeological sites

Monge, G. et al. (2015) Earliest evidence of pollution by heavy metals in archaeological sites. Scientific Reports, 5, 14252. (doi: 10.1038/srep14252) (PMID:26388184) (PMCID:PMC4585679)

Abstract

Homo species were exposed to a new biogeochemical environment when they began to occupy caves. Here we report the first evidence of palaeopollution through geochemical analyses of heavy metals in four renowned archaeological caves of the Iberian Peninsula spanning the last million years of human evolution. Heavy metal contents reached high values due to natural (guano deposition) and anthropogenic factors (e.g. combustion) in restricted cave environments. The earliest anthropogenic pollution evidence is related to Neanderthal hearths from Gorham's Cave (Gibraltar), being one of the first milestones in the so-called “Anthropocene”. According to its heavy metal concentration, these sediments meet the present-day standards of “contaminated soil”. Together with the former, the Gibraltar Vanguard Cave, shows Zn and Cu pollution ubiquitous across highly anthropic levels pointing to these elements as potential proxies for human activities. Pb concentrations in Magdalenian and Bronze age levels at El Pirulejo site can be similarly interpreted. Despite these high pollution levels, the contaminated soils might not have posed a major threat to Homo populations. Altogether, the data presented here indicate a long-term exposure of Homo to these elements, via fires, fumes and their ashes, which could have played certain role in environmental-pollution tolerance, a hitherto neglected influence.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Garcia-Alix Daroca, Dr Antonio
• Authors: Monge, G., Jimenez Espejo, F. J., Garcia-Alix Daroca, A., Martinez-Ruiz, F., Mattielli, N., Finlayson, C., Ohkouchi, N., Cortés-Sánchez, M., Bermúdez de Castro, J. M., Blasco, R., Rosell, J., Carrión, J., Rodríguez-Vidal, J., and Finlayson, G.
• College/School: College of Science and Engineering > School of Geographical and Earth Sciences
• Journal Name: Scientific Reports
• Publisher: Nature Publishing Group
• ISSN: 2045-2322
• ISSN (Online): 2045-2322
• Copyright Holders: Copyright © 2015 The Authors
• First Published: First published in Scientific Report 5:14252
• Publisher Policy: Reproduced under a Creative Commons License