Tracking natural and anthropogenic Pb exposure to its geological source

Evans, Jane; Pashley, Vanessa; Madgwick, Richard; Neil, Samantha; Chenery, Carolyn

Abstract

Human Pb exposure comes from two sources: (i) natural uptake through ingestion of soils and typified by populations that predate mining activity and (ii) anthropogenic exposure caused by the exposure to Pb derived from ore deposits. Currently, the measured concentration of Pb within a sample is used to discriminate between these two exposure routes, with the upper limit for natural exposure in skeletal studies given as 0.5 or 0.7 mg/kg in enamel and 0.5/0.7 μg/dL in blood. This threshold approach to categorising Pb exposure does not distinguish between the geological origins of the exposure types. However, Pb isotopes potentially provide a more definitive means of discriminating between sources. Whereas Pb from soil displays a crustal average 238U/204Pb (μ) value of c 9.7, Pb from ore displays a much wider range of evolution pathways. These characteristics are transferred into tooth enamel, making it possible to characterize human Pb exposure in terms of the primary source of ingested Pb and to relate mining activity to geotectonic domains. We surmise that this ability to discriminate between silicate and sulphide Pb exposure will lead to a better understanding of the evolution of early human mining activity and development of exposure models through the Anthropocene.

Citation

Evans, J., Pashley, V., Madgwick, R., Neil, S., & Chenery, C. (2018). Tracking natural and anthropogenic Pb exposure to its geological source. Scientific Reports, 8(1), Article 1969. https://doi.org/10.1038/s41598-018-20397-y

• Journal Article Type: Article
• Acceptance Date: Jan 17, 2018
• Online Publication Date: Jan 31, 2018
• Publication Date: Jan 31, 2018
• Deposit Date: Feb 15, 2018
• Publicly Available Date: Feb 15, 2018
• Journal: Scientific Reports
• Electronic ISSN: 2045-2322
• Publisher: Nature Research
• Peer Reviewed: Peer Reviewed
• Volume: 8
• Issue: 1
• Article Number: 1969
• DOI: https://doi.org/10.1038/s41598-018-20397-y
• Public URL: https://durham-repository.worktribe.com/output/1339634