Evaluation of the Levels of Hydroquinone and Health Risk Assessment of Toxic Metals in Skin-Whitening Creams

Abstract

This study assessed the level of toxic metals and hydroquinone in skin-lightening-creams commonly use in Ogun State, Nigeria. The pH of all the cream samples was determined and metals quantification was carried out using ICP-OES after acid digestion while that of hydroquinone was done using HPLC. The health risk of dermal exposure to heavy metals via the regular application was done by evaluating the carcinogenic and non-carcinogenic risk. The pH of all the samples are acidic and it follows this trend; Sample 3 > Sample 1 > Sample 4 > Sample 2. All the metals considered in this study were detected in all the analyzed samples except Cd, Co and Cr in sample 1, As, Ba and Pb in sample 2, Ag, As and Hg in sample 3 and Ba in sample 4. Highest levels of Al, Co, Pb and Zn were recorded in Sample 3 (Organic cream). Though the concentrations of most of the toxic metals (Al, Zn and Mn) are above the permissible levels, they pose no non-carcinogenic health risk based on the calculated HQ and HI. The carcinogenic risk of metals in the sampled creams were all within the acceptable limit except that of Cd. Hydroquinone was detected in all the four samples analyzed ranging between 2.58 and 4.17 % which exceeded the permissible limit by WHO. This finding show that long-term use of skin-whitening-creams may pose serious health hazards so, public should be continually enlightening on the hazardous health effects of the use.