The analysis of trace elements in human hair for use as
biomarkers continues to generate considerable interest in environmental
and bioanalytical studies, medical diagnostics, and forensic science. This
study investigated the concentrations of essential and toxic elements (Fe, Mg, Ca, Cu, Zn, Cr, Cd,
and Pb) using flame atomic absorption spectroscopy (FAAS) in human scalp hair
obtained from subjects living in Forsyth County, North Carolina, USA. The
influence of age, sex, race, and smoking habits on the levels of trace elements
in the hair samples were also investigated. Additionally, analyses
were subjected to a statistical, regression, and principal component analysis
to evaluate inter-elemental association and possible pattern recognition in
hair samples. Furthermore, Ca/Mg and Zn/Cu ratios, which are often used to
evaluate the degree of Ca and Cu utilization in humans and as markers for
various health related issues including, atherosclerosis, hypertension, insulin
sensitivity, and pancreatic cancer, were calculated. The overall mean concentrations
of Fe (25 μg/g), Ca (710 μg/g), Mg (120 μg/g), Zn (190 μg/g), Cu (12 μg/g), and
Cr (0.20 μg/g) were found in hair samples. The trace element concentrations
varied widely in hair samples as demonstrated by large range of concentrations
obtained for each element. However, levels of Cd and Pb elements of <0.030
μg/g were detected in hair sample. In general, the levels of the trace elements
in hair samples were poorly correlated. However, significant correlations were
found between Ca and Mg (r = 0.840, p = 0.05). The levels of Fe, Ca, Mg, Zn,
Cu, and Cr in hair samples and the calculated Ca/Mg and Zn/Cu ratios were found
to be largely correlated with age, race, sex, and smoking habits.