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Strontium Fsotope Ratios of Human Hair Record Intra-city Variations in Tap Water Source

NCJ Number
Brett J. Tipple; Luciano O. Valenzuela; James R. Ehleringer
Date Published
8 pages
In order to better understand the impact of various contributions to the spatial signal encoded within 87Sr/86Sr of hair, human hair was collected from three locations within Salt Lake City, Utah along with the donor's sex.
The oxygen (18O/16O) isotope analysis of hair is commonly applied to reconstruct an individual's residence history; however, region-of-origin as determined from oxygen isotope values (delta18O) alone is often spatially indistinct. Adding additional geochemical recorders can refine region-of-origin estimates. In this capacity, strontium (87Sr/86Sr) isotope analysis has attracted increased interest. Although 87Sr/86Sr reflects the influences of local geology, 87Sr/86Sr of hair includes both external environmental signals as well as the internal dietary indicators. In the current study, the 87Sr/86Sr and delta 18O of hair and local tap water were measured. There were no significant relationships between sex and either delta 18O or 87Sr/86Sr of hair, nor between collection location and the delta 18O of hair; however, the study found significant associations between collection location and 87Sr/86Sr of hair. These findings suggest that interactions with local water may be an important source of Sr to human hair and that the 87Sr/86Sr of hair may have the capacity to record differences in 87Sr/86Sr of tap waters on small spatial scales. (publisher abstract modified)

Date Published: January 1, 2018