Risk assessment of heavy metals content in different hair dyes and their users’ urine samples

Abstract

Human toxicity of heavy metals is the result of long-term exposure to pollutants found in hair dyes. In this study, levels of lead (Pb), cadmium (Cd), mercury (Hg) and urine were evaluated in various hair dyes products sold in local stores in Riyadh using inductive coupled plasma optical emission spectrometry (ICP-OES) after digestion with a mixture of nitric acid (HNO3), hydrofluoric acid (HF) and hydrogen peroxide (H2O2) for hair dyes, while a mixture of HNO3 and H2O2 was used for urine. The mean concentrations of the selected heavy metals in hair dye ranged (0.0015–0.0035 ppm) from Cd, (0.003–0.014 ppm) from Pb, which were within the permissible international limits, while for Hg (1.1–4.3 ppm) from Hg was higher than the permissible international limits. The mean concentrations of the selected heavy metals in urine ranged (0. 002, 0.011 and 1.3 ppm) from Cd, Pb, and Hg respectively in the urine. However, in the case of urine samples, the average concentration of Pb was higher than the permitted international limits. The current study showed that the use of hair dyes exposes users to low concentrations of toxic heavy metals that can cause potential health damage to users.