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

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 (r2 = 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, r2, 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.

A preliminary study of skin bleaching and factors associated with skin bleaching among women living in Zimbabwe

Background

Skin bleaching was reported to be commonly practiced among women and Africa was reported to be one of the most affected yet the subject is not given much attention in public health research in Zimbabwe despite the adverse effects of skin bleaching on health.

Method

This study was an exploratory cross-sectional survey to explore skin bleaching, skin bleaching patterns and factors associated with skin bleaching among women living in Zimbabwe. An online self-administered questionnaire was sent out to women on social network i.e. WhatsApp, Facebook, LinkedIn and Twitter.

Findings

A total number of 260 respondents, mean age 31.69 (SD, 8.12) years participated in the survey. The prevalence of skin bleaching among the participants was 31.15%. The major reason reported for skin bleaching was to have smooth and healthy skin alongside other factors such as beauty, gaining social favours for example getting married and good jobs. Occupation, complexion and marital status were associated with skin bleaching. The odds of skin bleaching for participants who were employed was 1.45(95% confidence interval [CI],0.32–1.91);p-value 0.02, dark skinned participants 2.56(95% CI, 0.76–2.87);p-value 0.01 and unmarried participants 2.87(95% CI,0.29–3.58);p-value 0.03.

Conclusion

Evidence from the research suggests skin bleaching might be common among women living in Zimbabwe and possibly poses serious health threats to the women. Skin bleaching seems to be deep rooted in colourism. The colourism seems to be taken advantage of by the cosmetic industry which produce the potentially hazardous products which promise the revered light skin to women but which comes with a price. However, the study provides a base for future studies to explore more on skin bleaching practices among women living in Zimbabwe.

A Topical Depigmentation Program Against Hyperpigmentation Enhances the Benefits of Previously Performed Chemical Peeling Procedures of the Face

Chemical peeling can reduce skin hyperpigmentation; however, once exhausted its thinning action, the depigmentation process does not continue further. We carried out a monocentric, prospective, noncontrolled study aimed at the evaluation of the efficacy, safety, ease of use, pleasantness, and tolerability of a depigmentation topical treatment program in women submitted to a previous chemical peeling. The topical treatment has been administered daily for 30 days to 16 women submitted to a chemical peeling containing a fixed-dose combination of salicylic acid, pyruvic acid, and retinoic acid within 7 days before study inclusion. Target skin areas have been evaluated for melanin concentration and skin texture before peeling and at study visits 1 (after peeling) and 2 (after the 30-day treatment). The topical treatment program induced a decrease in melanin concentration between study visits 1 and 2 (-4.74%; p = 0.0008). It reduced melanin concentration even further between the prepeeling period and visit 2 (-7.8%; p < 0.0001). Patients rated the depigmentation topical treatment program as "very simple" (87.5%) and "simple" (12.5%) to use and as "pleasant" (56.25%) and "very pleasant" (43.75%). Results support the use of the home-based depigmentation topical treatment program to potentiate the effectiveness of a previous chemical peeling in hyperpigmentation reduction.

Marine-Derived Compounds with Potential Use as Cosmeceuticals and Nutricosmetics

The cosmetic industry is among the fastest growing industries in the last decade. As the beauty concepts have been revolutionized, many terms have been coined to accompany the innovation of this industry, since the beauty products are not just confined to those that are applied to protect and enhance the appearance of the human body. Consequently, the terms such as cosmeceuticals and nutricosmetics have emerged to give a notion of the health benefits of the products that create the beauty from inside to outside. In the past years, natural products-based cosmeceuticals have gained a huge amount of attention not only from researchers but also from the public due to the general belief that they are harmless. Notably, in recent years, the demand for cosmeceuticals from the marine resources has been exponentially on the rise due to their unique chemical and biological properties that are not found in terrestrial resources. Therefore, the present review addresses the importance of marine-derived compounds, stressing new chemical entities with cosmeceutical potential from the marine natural resources and their mechanisms of action by which these compounds exert on the body functions as well as their related health benefits. Marine environments are the most important reservoir of biodiversity that provide biologically active substances whose potential is still to be discovered for application as pharmaceuticals, nutraceuticals, and cosmeceuticals. Marine organisms are not only an important renewable source of valuable bulk compounds used in cosmetic industry such as agar and carrageenan, which are used as gelling and thickening agents to increase the viscosity of cosmetic formulations, but also of small molecules such as ectoine (to promote skin hydration), trichodin A (to prevent product alteration caused by microbial contamination), and mytiloxanthin (as a coloring agent). Marine-derived molecules can also function as active ingredients, being the main compounds that determine the function of cosmeceuticals such as anti-tyrosinase (kojic acid), antiacne (sargafuran), whitening (chrysophanol), UV protection (scytonemin, mycosporine-like amino acids (MAAs)), antioxidants, and anti-wrinkle (astaxanthin and PUFAs).

[Hookworm-related folliculitis in a woman performing skin bleaching in Benin]

Hookworm-related cutaneous larva migrans is caused by the subcutaneous migration of hookworm larvae. The characteristic sign is a serpiginous cutaneous track. Folliculitis is an uncommon clinical manifestation. We report a case of hookworm-related folliculitis in a woman performing skin bleaching. A 33-year-old woman presented with a widespread cutaneous eruption made of erythematous and itchy follicular papulo-nodules, with erythematous serpiginous tracks, about 5-10cm long and numerous streaks of scratching, located on the limbs, buttocks and trunk. The cutaneous lesions occurred two days after contact with the floor of a warehouse contamined by faeces of cats. The lesions have been evolving for a week and have been treated with antibiotics without success. Clinical examination found cutaneous atrophy, purple stretch marks and hyperpigmentation of dorsal parts of fingers joints. The patient reported having been using bleaching cosmetics containing topical steroids and hydroquinone for twelve years. She was cured within 4 weeks with oral albendazole 400mg per day during 7 consecutive days.

Skin whitening agents: medicinal chemistry perspective of tyrosinase inhibitors

Melanogenesis is a process to synthesize melanin, which is a primary responsible for the pigmentation of human skin, eye and hair. Although numerous enzymatic catalyzed and chemical reactions are involved in melanogenesis process, the enzymes such as tyrosinase and tyrosinase-related protein-1 (TRP-1) and TRP-2 played a major role in melanin synthesis. Specifically, tyrosinase is a key enzyme, which catalyzes a rate-limiting step of the melanin synthesis, and the downregulation of tyrosinase is the most prominent approach for the development of melanogenesis inhibitors. Therefore, numerous inhibitors that target tyrosinase have been developed in recent years. The review focuses on the recent discovery of tyrosinase inhibitors that are directly involved in the inhibition of tyrosinase catalytic activity and functionality from all sources, including laboratory synthetic methods, natural products, virtual screening and structure-based molecular docking studies.

[High school student and skin bleaching in Cameroon]

Introduction: Skin bleaching is a common practice in Africa, particularly in Cameroon. Studies show that it represents a danger for health, in terms of a demonstrated increased risk of dermatological diseases. However, increasing numbers of people are using skin bleaching in African cities, despite the fact that they are sometimes aware of the risk. This study proposed to transform the knowledge and perceptions of skin bleaching practices into educational strategies that can be used both by health professionals and educators. These strategies can also be used as preventive measures against skin bleaching among young schoolgirls. Methods: Data collection was based on a qualitative approach, in the form of a focus group discussion attended by 40 girls aged between 14 and 20 years, selected by convenient random sampling. Results: The results indicated that girls have an approximate knowledge about the consequences of skin bleaching on their health. On the contrary, they have a good knowledge about prevention, which can be used to develop a prevention strategy in order to reduce or eradicate skin bleaching, by educational awareness campaigns Conclusion: These elements can be used as a basis for better prevention and health promotion in schools; so that students adopt healthy behaviours and to prevent those students at risk.

Curcuma aeruginosa Roxb. essential oil slows hair-growth and lightens skin in axillae; a randomised, double blinded trial

BACKGROUND

Androgenic hair-growth contributes to secondary gender characteristics but can be troublesome in women. Inhibiting axillary hair-growth via 5-α-reductases using the Thai medicinal plant, Curcuma aeruginosa Roxb. is an attractive treatment strategy.

HYPOTHESIS/PURPOSE

C. aeruginosa essential oil (CA-oil) formulated as a lotion is an efficacious and safe inhibitor of axillary hair growth.

STUDY DESIGN

This trial was a single center, randomized, double-blind, placebo controlled 10 weeks, intervention in 60 women (18-23 years) and 2 weeks washout with axillary hair length was the primary end-point.

METHODS

Bioactive-enriched essential oil of C. aeruginosa was formulated with a base lotion. All participants were pre-challenged with lotions by 4-h patch irritation tests to exclude skin reactions. Participants were randomly allocated to use either 1 or 5%w/w CA-oil lotion on one axilla and base-lotion (placebo) to the other for 10 weeks followed by placebo in both axillae for 2 weeks. Every week, the axillae were photographed to measure hair lengths, shaved, and roll-on applicators containing appropriate lotion replaced. Also, skin melanin by spectrophotometry and hair density were measured.

RESULTS

From weeks 5-11 of trial, 1 and 5%w/w CA-oil retarded growth by 13 ± 1.5% and 16 ± 0.9% respectively, while placebo was ineffective. CA-oil had no influence on hair density. Both concentrations of CA-oil rapidly and equally effectively brightened skin within 3 weeks which persisted 2 weeks after treatment ceased while placebo darkened the skin. Adherence appeared good as judged by consistency of lotion consumption and between axillae. Participants were satisfied with the treatment and reported reduced hairiness, freedom from any discomforts, but product odour attracted some negative comment. No adverse reactions ascribed to CA-oil were detected or reported.

CONCLUSION

This study points to a safe and efficacious dual action on retarding hair-growth and skin lightening by CA-oil.

Inhibitory effects of pomegranate concentrated solution on the activities of hyaluronidase, tyrosinase, and metalloproteinase

Synopsis Botanical antioxidants have attracted much attention as useful preventatives of skin damage. Pomegranate is consumed throughout the world for its beneficial health effects, including its antioxidant and anti-inflammatory activities. We investigated whether pomegranate concentrated solution (PCS) could serve as a potential functional cosmetic ingredient that exerts a skin-whitening effect and antiwrinkle activity. To investigate the moisturizing effect of PCS, hyaluronidase activity was examined in human keratinocytes (HaCaT). Elastase and procollagenase activities were assessed in normal human primary dermal fibroblast-neonatal (HDF-N) cells to determine their antiwrinkle effects. Metalloproteinase 1 (MMP-1) activity was also assessed following ultraviolet A (UVA) irradiation. Whitening effects were measured by a tyrosinase inhibition assay and melanin formation test in mouse melanocytes (Melan-a). In addition, histopathological analysis was performed to determine the number of microfolds formed on the epithelial surface, mean epithelial thickness, mean number of inflammatory cells infiltrating the dermis, and collagen fiber-occupied regions within the dermis. Hyaluronan synthesis was significantly increased by PCS in HaCaT cells, while procollagenase and elastase activities were decreased in HDF-N cells. A significant decrease in UVA-induced MMP-1 activity was also observed in PCS-treated HDF-N cells, compared with UVA-exposed cells. PCS effectively reduced melanin production and mushroom tyrosinase activity in Melan-a cells. Moreover, UVB-induced histopathological dermal sclerosis and inflammatory signs were significantly attenuated in PCS-administered mice compared with UVB-exposed mice. Conclusions: Our results suggest that PCS prevents signs of aging, including those related to photoaging. These effects are associated with enhanced hyaluronan synthesis, as well as suppressed elastase, collagenase, MMP-1, and tyrosinase activities and melanin production. UVB-induced photoaging, such as histopathological dermal sclerosis and inflammatory signs, were effectively reduced on the addition of PCS. These results also suggest that skin aging can be prevented and reduced by the antioxidant effects of PCS.

Proteomics links the redox state to calcium signaling during bleaching of the scleractinian coral Acropora microphthalma on exposure to high solar irradiance and thermal stress

Shipboard experiments were each performed over a 2 day period to examine the proteomic response of the symbiotic coral Acropora microphthalma exposed to acute conditions of high temperature/low light or high light/low temperature stress. During these treatments, corals had noticeably bleached. The photosynthetic performance of residual algal endosymbionts was severely impaired but showed signs of recovery in both treatments by the end of the second day. Changes in the coral proteome were determined daily and, using recently available annotated genome sequences, the individual contributions of the coral host and algal endosymbionts could be extracted from these data. Quantitative changes in proteins relevant to redox state and calcium metabolism are presented. Notably, expression of common antioxidant proteins was not detected from the coral host but present in the algal endosymbiont proteome. Possible roles for elevated carbonic anhydrase in the coral host are considered: to restore intracellular pH diminished by loss of photosynthetic activity, to indirectly limit intracellular calcium influx linked with enhanced calmodulin expression to impede late-stage symbiont exocytosis, or to enhance inorganic carbon transport to improve the photosynthetic performance of algal symbionts that remain in hospite. Protein effectors of calcium-dependent exocytosis were present in both symbiotic partners. No caspase-family proteins associated with host cell apoptosis, with exception of the autophagy chaperone HSP70, were detected, suggesting that algal loss and photosynthetic dysfunction under these experimental conditions were not due to host-mediated phytosymbiont destruction. Instead, bleaching occurred by symbiont exocytosis and loss of light-harvesting pigments of algae that remain in hospite. These proteomic data are, therefore, consistent with our premise that coral endosymbionts can mediate their own retention or departure from the coral host, which may manifest as "symbiont shuffling" of Symbiodinium clades in response to environmental stress.