title: Earliest evidence of pollution by heavy metals in archaeological sites.
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.
authors.affiliation: Departamento de Cristalografía, Mineralogía y Química Agrícola, Facultad de Química, Universidad de Sevilla, Spain.
authors.forename: Guadalupe
authors.initials: G
authors.lastname: Monge
authors.affiliation: Department of Biogeochemistry, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Jimenez-Espejo
authors.affiliation: Department of Geographical and Earth Sciences, University of Glasgow, UK.
authors.forename: Antonio
authors.initials: A
authors.lastname: García-Alix
authors.affiliation: Instituto Andaluz de Ciencias de la Tierra CSIC-UGR, Granada, Spain.
authors.forename: Francisca
authors.initials: F
authors.lastname: Martínez-Ruiz
authors.affiliation: Laboratoire G-Time, DSTE, Université Libre Bruxelles (ULB), Brussels, Belgium.
authors.forename: Nadine
authors.initials: N
authors.lastname: Mattielli
authors.affiliation: The Gibraltar Museum, Gibraltar, UK.|Institute of Life and Earth Sciences, The University of Gibraltar, Gibraltar.
authors.forename: Clive
authors.initials: C
authors.lastname: Finlayson
authors.affiliation: Department of Biogeochemistry, Japan Agency for Marine-Earth Science and Technology, Yokosuka, Japan.
authors.forename: Naohiko
authors.initials: N
authors.lastname: Ohkouchi
authors.affiliation: Departamento de Prehistoria y Arqueología, Facultad de Geografía e Historia, Universidad de Sevilla, Sevilla, Spain.
authors.forename: Miguel Cortés
authors.initials: MC
authors.lastname: Sánchez
authors.affiliation: Centro Nacional de Investigación sobre la Evolución Humana (CENIEH) Burgos, Spain.|University College London Anthropology, London, UK.
authors.forename: Jose María Bermúdez
authors.initials: JM
authors.lastname: de Castro
authors.affiliation: Departament de Prehistòria, Universitat Autònoma de Barcelona, Barcelona, Spain.
authors.forename: Ruth
authors.initials: R
authors.lastname: Blasco
authors.affiliation: Àrea de Prehistòria, Universitat Rovira i Virgili (URV), Tarragona, Spain.|Institut Català de Paleoecologia Humana i Evolució Social (IPHES), Tarragona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Rosell
authors.affiliation: Departamento de Biología Vegetal, Universidad de Murcia, Murcia, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Carrión
authors.affiliation: Departamento de Geodinámica y Paleontología, Facultad de Ciencias Experimentales, Universidad de Huelva, Huelva, Spain.
authors.forename: Joaquín
authors.initials: J
authors.lastname: Rodríguez-Vidal
authors.affiliation: The Gibraltar Museum, Gibraltar, UK.|Institute of Life and Earth Sciences, The University of Gibraltar, Gibraltar.
authors.forename: Geraldine
authors.initials: G
authors.lastname: Finlayson
mesh_terms: D000383:Agriculture; D000818:Animals; D001106:Archaeology / Q000379:methods*; D059552:Caves; D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000032:analysis*; D006801:Humans; D007221:Industry; D019216:Metals, Heavy / Q000032:analysis*; D059125:Neanderthals; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants