Quality assessment of hydroquinone, mercury, and arsenic in skin-lightening cosmetics marketed in Ilorin, Nigeria

• Published in: Scientific reports 2023-11, Vol.13 (1), p.20992-20992, Article 20992
• Main Authors: Bamidele, Olasunkanmi David, Kayode, Blessing Ayomide, Eniayewu, Oluwasegun Ibrahim, Adegbola, Adebanjo Jonathan, Olatoye, Raphael Segun, Njinga, Ngaitad Stanislaus, Abdullahi, Sa’ad Toyin, Bakare-Odunola, Moji Taibat
• Format: Article
• Language: English
• Subjects: 639/638/899; 704/172/169; Arsenic; Arsenic - analysis; Atomic absorption spectrophotometry; Cosmetics; Cosmetics - analysis; Humanities and Social Sciences; Hydroquinone; Hydroquinones; Mercury; Mercury - analysis; multidisciplinary; Nigeria; Quality control; Science; Science (multidisciplinary); Skin; Skin Lightening Preparations; Spectral analysis; Spectrophotometry
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-023-47160-2

Hydroquinone, Mercury (Hg), and Arsenic (As) are hazardous to health upon long-term exposure. Hydroquinone, Hg, and As were analysed in skin-lightening cosmetics randomly purchased from different cosmetic outlets within the Ilorin metropolis, Nigeria. The amount of hydroquinone in the samples was determined using a UV-spectrophotometry method at 290 nm. Hg and As were quantified using atomic absorption spectrophotometry (AAS). UV-spectrophotometry method validation showed excellent linearity (r 2  = 0.9993), with limits of detection (0.75 µg/mL), limits of quantification (2.28 µg/mL), relative standard deviation (0.01–0.35%), and recovery (95.85–103.56%) in the concentration range of 5–50 µg/mL. Similarly, r 2 , LOD, and LOQ for Hg and As were 0.9983 and 0.9991, (0.5 and 1.0 µg/L) and 1.65 and 3.3 µg/L) respectively. All the samples contained hydroquinone, Hg and As in varying amounts. The amounts of hydroquinone, Hg and As present were in the ranges of 1.9–3.3%, 0.08–2.52 µg/g and 0.07–5.30 µg/g respectively. Only three of the analysed samples contained hydroquinone within the permissible limit of 2.0% w/w in cosmetic products. All the samples analysed contained mercury and arsenic in varying amounts. The need to periodically monitor the levels of hydroquinone, mercury, and arsenic in skin-lightening cosmetics marketed in Nigeria is recommended.