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Strontium Isotope Ratios of Human Hair Record Intra-City Variations in Tap Water Source

NCJ Number
255707
Date Published
2018
Length
6 pages
Author(s)
Brett J. Tipple; Luciano Valenzuela; James R Ehleringer
Agencies
NIJ-Sponsored
Annotation
In order to better understand the impact of identified 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.
Abstract
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 (18O) 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 18O of hair and local tap water were measured. There were no significant relationships between sex and either 18O or 87Sr/86Sr of hair, nor between collection location and the 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 Created: July 20, 2021