Safety Evaluation of Metal Exposure From Commonly Used Hair Dyes and Tattoo Inks in Nigeria.

In the study described in this article, the concentrations of metals (cadmium, copper, chromium, aluminum, lead, nickel, zinc, cobalt, manganese, and iron) in samples of some commonly used hair dyes and tattoo inks were determined with a view to providing information on the hazards associated with the use of these products. The concentrations of metals were measured after nitric acid/perchloric acid/hydrogen peroxide digestion by atomic absorption spectrometry. Results indicated that the tattoo ink samples contained allergenic metals such as nickel, chromium, and cobalt at concentrations above the suggested limit of 1 μg/g for greater skin protection, and the toxic metals were below their respective prescribed limits, as impurities in ingredients for use for cosmetics, in the majority of the samples.