INTRODUCTION: Skin whitening (SW) is very common in dark-skinned populations and the practice is often named after a popular local brand of product and such is the case in Mayotte where this practice is called "pandalao". PATIENTS AND METHODS: We carried out a descriptive epidemiological study in a sample of black Mahoran women aged 15 and over. The survey comprised a questionnaire completed by 163 women between 12 November 2007 and 24 January 2008. The aim of our study was to investigate the practice of SW in Mayotte and to determine its prevalence. RESULTS: Hundred percent of the subjects were aware of SW and 95% knew people practicing this procedure. The prevalence of users of whitening products was 33%, although 74% of these subjects did not use such products on a regular basis and 89% of the women limited application to exposed areas (visible to others). Sixty-three percent simultaneously applied Diproson (betamethasone dipropionate) and Pandalao, the main component of which is salicylic acid. Fifty-four percent of users had presented one or more adverse effects after application of these products and 28% had stopped this practice due to such adverse effects (chiefly acne and dyschromia). DISCUSSION: Although illegal, the trade in skin whitening products continues to grow because it is profitable and takes full advantage of the success of ethnic cosmetics. In Mayotte, as in metropolitan France and Africa, the existence of SW is acknowledged but is still taboo. However, a number of specific characteristics are seen in Mayotte: SW is rarely performed on the whole body, salicylic acid is added to a topical corticosteroid, and the traditional Mahoran mask, the "mzindzano", is still worn for photoprotection.