Comparison between elemental composition of human fingernails of healthy and opium-addicted subjects by laser-induced breakdown spectroscopy.

The objective of the present work is to identify differences in elemental fingernail composition between opium-addicted and healthy adult human subjects using laser-induced breakdown spectroscopy. Thirty nails from normal, healthy male subjects and 30 nails from opium-addicted male individuals were analyzed. Measurements on 60 nail samples were carried out, identifying 13 key species including 11 neutral elements and 2 ions. Discriminant Function Analysis (DFA) was used to classify the samples between the two groups. Spectral line intensities of elements including Fe, C, Ti, Mg, Si, Al, Ca, H, K, O, and Na were considered variables in DFA. This analysis demonstrates the efficient discrimination between the two groups. However, the number of samples in this work is not sufficient for a decisive conclusion and further research is needed to generalize this idea.