JA SANSONI, Department of Anthropology, University of Notre Dame, Notre Dame, IN  46556
SG SHERIDAN, Department of Anthropology, University of Notre Dame, Notre Dame, IN  46556
DP VAN GERVEN, Department of Anthropology, University of Colorado, Boulder, CO  80309

Fluorine analysis is used to measure the diagenetic alteration of deposited bone that has come into contact with fluoride ions present in ground water.  In this study, percent fluoride (%F) was used to analyze a sample of human remains to determine whether the sample could be separated diachronically into early and late components, based on %F content in bone.

The skeletal remains used in this study came from the Hohokam site of Pueblo Grande in Arizona.  Based on associated grave goods, these individuals have been dated to the Classic Period (A.D. 1050-1450).  The Pueblo Grande area receives a semi-annual rainfall that floods the region providing an excellent medium for the exchange of minerals across the bone surface.  Large amounts of caliche (a clay-like substance) were extracted from the bones during the cleaning process, indicating some degree of post-depositional alteration.  Femoral mid-shaft sections were utilized from sixty-eight adults of both sexes, ranging in age from 18 to 50+ years. Fluorine analysis was conducted using an ion selective electrode.

First, comparisons were made to see if two distinct groupings in fluoride levels existed to indicate two chronologically different burial groups.  No significant difference was found with time using ANOVA (p=0.15), although a trend towards decreasing %F was evident.

Demographic variables of age and sex were then analyzed to determine possible antemortem fluoride patterns.  When males and females were compared using Student’s t-test, no significant difference was found (p=0.07).  However, when %F was regressed on age, a significant increase in %F corresponding to an increase in age was noted (p=0.04).  This relationship was minimal, however, with an associated r2 value of 0.081 (r=0.28).

In conclusion, the fluoride values did not produce a chronological distinction for the two groups.  The burials may not have been diachronically distinct enough for fluorine analysis to be a viable measure of chronological order.  However, antemortem patterns correlating increasing %F content with increasing age did exist for this population.  These patterns mirror antemortem fluorine patterns, and are rarely seen in an archaeological setting.

*This research was supported by the Undergraduate Research Opportunities Program,  the Institute for Scholarship in the Liberal Arts, University of Notre Dame, and Soil Systems Incorporated, Phoenix, Arizona.