African Journal of Biotechnology Research

African Journal of Biotechnology Research ISSN 9316-2194 Vol. 4 (5), pp. 189-194, May, 2016.  © International Scholars Journals

Full Length Research Paper

Determination of the hydroquinone and mercury contents on different skin whitening cosmetics and their possible preventions to long-term adverse effect

Dafitokwo Emmanuel*, F. O. Oturke, Ugbunu H. Bright and M. M. Chiamaka

Department of Pure and Industrial Chemistry, Faculty Of Physical Sciences, Nnamdi Azikiwe University, P.M.B. 5025, Awka, Anambra State, Nigeria.


Accepted 31 April, 2015


In this study, thirty cosmetic skin lightening emulsions (lotions and tubes) were randomly purchased from an open market in Awka and Enugu cities of Southern Nigeria with the aim of finding out if the creams contained hydroquinone and mercury at levels which were harmful to the users. Their physico-chemical properties like pH which ranged from 4.25 - 7.25 and moisture content from below 20 to 90% were also determined. The concentration of mercury in the creams ranged from below 0.00 to 200 µg/g and that of hydroquinone ranged from 0.288 - 2.35%. Mercury was not detected in most of the creams analyzed, only two samples (1 and 17) contained mercury at a much higher concentration (200 and 100 µg/g) than 1 µg/g which is the WHO limit. All the creams analyzed contained hydroquinone at concentration lower than 2% which is the recommended WHO limit except two creams with hydroquinone concentration barely higher than 2%. In conclusion, most of the creams do not contain hydroquinone or mercury at levels that are detrimental to human health and also most of the creams had pH and moisture content that will not irritate the skin, but rather provide adequate moisture and hydration to the skin.

Key words: Cosmetics, hydroquinone, mercury, emulsions, determination.