The coordination environment of copper in hair can be altered by treatment products

Abstract

Commercial hair treatment products can have a profound effect on the copper coordination environment in hair, and this must be taken into account in any attempt to use hair as a health marker.

Particulate matter adheres to human hair exposed to severe aerial pollution: consequences for certain hair surface properties

“…As an example, the amounts of airborne copper, present on the surface of non‐digested/solubilized hair fibres, are logically of a much lower range (0.1–0.8 μg g −1 ), than those found in digested/solubilized hair fibres (i.e. trapped by all hair sub‐structures) that range 30–140 μg g −1 . According to these studies, a significant part of this hair‐trapped copper is waterborne, such as the one added in swimming pools (copper sulphate), as a germicide, or from old copper‐based plumbing pipes, now progressively replaced by plastic polymers, for safety reasons.…”

“…140 lg g À1 [25,26]. According to these studies, a significant part of this hair-trapped copper is waterborne, such as the one added in swimming pools (copper sulphate), as a germicide, or from old copper-based plumbing pipes, now progressively replaced by plastic polymers, for safety reasons.…”

Forensic determination of hair deposition time in crime scenes using electron paramagnetic resonance

“…Melanins capture a large fraction of UV‐visible radiation resulting in the formation of free radicals which could be stabilized by resonance, thereby preventing the propagation of this chain reaction into the keratin matrix [28,29]. Natural melanin and melanin‐like pigments are characterized by a persistent radical signal due to the presence of exceptionally stable free radicals [30–32] which can be detected by electron paramagnetic resonance spectroscopy (EPR; [33–55]). While most of these studies were performed by evaluating stable radical signals present in human hair, few followed the decay of the signals with time (for example [49]) and mainly after gamma‐ or UV‐irradiation of hair [34,38,39,41,43,48–51,56].…”