Knox and colleagues exposed human skin to nickel(II), cobalt(II), and chromium(III) salts and measured changes in skin lipids. The metal result that is numeric in the methods is the applied concentration, not a concentration left in the skin. Each salt was applied at 0.15 M for 24 hours. The experiment used one donor and three replicates. No tissue or receptor metal concentration is transcribed from this paper.
Key numbers
Applied solutions: nickel(II) sulfate hexahydrate 0.15 M, cobalt(II) chloride hexahydrate 0.15 M, and chromium(III) chloride hexahydrate 0.15 M, in ammonium formate buffer at pH 7.4. Controls were buffer without the metal salt. Lipid changes are directional and are not converted into metal concentrations.
Methods (brief)
Ex vivo skin, 24 h, room temperature, mass-spectrometric lipid imaging. Chromium is the trivalent salt, not chromium(VI).
Evidence fitness
The paper supports a statement about the applied dose in a lipid experiment. It does not support an occurrence or absorption concentration.
Limitations
One donor. No recovered metal mass in tissue. Cobalt is part of the design even though the metal list emphasises nickel and chromium.
Related evidence
Update history
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