Current status of mercury level in skin whitening creams

Effects of Sapindus mukorossi Seed Oil on Bone Healing Efficiency: An Animal Study

Natural products have attracted great interest in the development of tissue engineering. Recent studies have demonstrated that unsaturated fatty acids found in natural plant seed oil may exhibit positive osteogenic effects; however, few in vivo studies have focused on the use of plant seed oil for bone regeneration. The aim of this study is to investigate the effects of seed oil found in Sapindus mukorossi (S. mukorossi) on the osteogenic differentiation of mesenchymal stem cells and bone growth in artificial bone defects in vivo. In this study, Wharton-jelly-derived mesenchymal stem cells (WJMSCs) were co-cultured with S. mukorossi seed oil. Cellular osteogenic capacity was assessed using Alizarin Red S staining. Real-time PCR was carried out to evaluate ALP and OCN gene expression. The potential of S. mukorossi seed oil to enhance bone growth was assessed using an animal model. Four 6 mm circular defects were prepared at the parietal bone of New Zealand white rabbits. The defects were filled with hydrogel and hydrogel-S. mukorossi seed oil, respectively. Quantitative analysis of micro-computed tomography (Micro-CT) and histological images was conducted to compare differences in osteogenesis between oil-treated and untreated samples. Although our results showed no significant differences in viability between WJMSCs treated with and without S. mukorossi seed oil, under osteogenic conditions, S. mukorossi seed oil facilitated an increase in mineralized nodule secretion and upregulated the expression of ALP and OCN genes in the cells (p < 0.05). In the animal study, both micro-CT and histological evaluations revealed that new bone formation in artificial bone defects treated with S. mukorossi seed oil were nearly doubled compared to control defects (p < 0.05) after 4 weeks of healing. Based on these findings, it is reasonable to suggest that S. mukorossi seed oil holds promise as a potential candidate for enhancing bone healing efficiency in bone tissue engineering.

Development of Licorice Flavonoids Loaded Microemulsion for Transdermal Delivery Using CCD-Optimal Experimental Approach: Formulation Development and Characterization

In this research, we sought to surmount the poor dissolvability and transdermal absorption rate of licorice flavonoids (LFs) by fabricating a LFs microemulsion. LFs content was determined using high performance liquid chromatography. Initial studies such as dissolution testing, emulsification testing, and pseudo ternary phase diagram generation were implemented for screening components and optimized adopting the central composite design. While the tested responses were solubility, droplet size and PDI, thirteen trials were performed using two different variables, oil percentage and optimized emulsifier and co-emulsifier ratio. Microemulsions were then characterized for droplet size, PDI, transmission electron microscopy, viscosity, electrical conductivity, pH, entrapment efficiency, drug content and stability. Additionally, skin release profile, percutaneous absorption and retention were investigated adopting Franz diffusion cell. The optimal formulation was found to compose of laureth-9 (emulsifier, 6.72 g), propylene glycol (co-emulsifier, 1.80 g), isopropyl myristate (IPM, oil, 1.48 g), LFs (1.50 g) and at least more than 85% deionized water. The optimized and storage for 3 months of microemulsion was found to clear, light yellow color without phase separation or precipitation indicated the stability of the preparation to long-term placement. The mean droplet size, PDI, entrapment efficiency and drug content were discovered as 12.68 ± 0.12 nm, 0.049 ± 0.005, 97.28 ± 0.13% and 122.67 ± 0.40 mg·g−1, respectively. Furthermore, the optimal formulation sustained release LFs, remarkably deliver more LFs through the skin layer (644.95 ± 6.73 μg cm−2) and significantly retained LFs in the skin layer (9.98 μg cm−2). The study concluded that optimized microemulsion has potential and enhanced the dissolvability and cumulative penetration amount of LFs.

Algae as an attractive source for cosmetics to counter environmental stress

In recent times, a considerable amount of evidence has come to light regarding the effect that air pollution has on skin conditions. The human skin is the chief protection we have against environmental harm, whether biological, chemical, or physical. The stress from these environmental factors, along with internal influences, can be a cause of skin aging and enlarged pores, thinner skin, skin laxity, wrinkles, fine lines, dryness, and a more fragile dermal layer. This knowledge has led to greater demand for skin cosmetics and a requirement for natural raw ingredients with a high degree of safety and efficiency in combating skin complications. Recent developments in green technology have made the employment of naturally occurring bioactive compounds more popular, and novel extraction methods have ensured that the use of these compounds has greater compatibility with sustainable development principles. Thus, there is a demand for investigations into efficient non-harmful naturally occurring raw ingredients; compounds derived from algae could be beneficial in this area. Algae, both macroalgae and microalgae, consists of waterborne photosynthetic organisms that are potentially valuable as they have a range of bioactive compounds in their composition. Several beneficial metabolites can be obtained from algae, such as antioxidants, carotenoids, mycosporine-like amino acids (MAA), pigments, polysaccharides, and scytonemin. Various algae strains are now widely employed in skincare products for various purposes, such as a moisturizer, anti-wrinkle agent, texture-enhancing agents, or sunscreen. This research considers the environmental stresses on human skin and how they may be mitigated using cosmetics created using algae; special attention will be paid to external factors, both generally and specifically (amongst them light exposure and pollutants).

Mercury in skin-care products in India and consumer exposure risks

We report concentrations of mercury in skin-care products in India and the associated health risks. Mercury concentrations were 0.11 μg/kg (median; 5th percentile-95th percentile = 0.04-0.58 μg/kg; n = 24) in body lotions, 0.22 μg/kg (0.04-0.38 μg/kg, n = 10) in moisturizing lotions, 0.67 μg/kg (0.30-1.33 μg/kg, n = 8) in blemish balms, 0.16 μg/kg (0.06-7.43 μg/kg, n = 11) in bleaches, 0.13 μg/kg (0.04-0.98 μg/kg, n = 34) in skin lightning (fairness) creams manufactured within the country, and 9.24 × 10⁶ μg/kg (2.92 × 10⁶-3.17 × 10⁷ μg/kg, n = 14) in imported skin lightning (fairness) creams, much higher than the 1 ppm (1 ppm = 10³ μg/kg) regulatory limit. Probabilistic human health risk assessment for adult women (age > 21 y) revealed that computed hazard quotients from dermal exposure to the high-mercury fairness creams were >100 in all cases. The mass of mercury entering into the society via skin-care products is highly sensitive to the mass of high-mercury fairness creams that is imported to India; ten tonnes of import can introduce 29-317 kg of mercury every year. As such, analysis and labeling of mercury contents in skin-care products by manufacturers, and raising awareness among regulatory authorities to restrict the import of high-mercury fairness creams, is required.

Sapindus mukorossiSeed Oil Changes Tyrosinase Activity of α-MSH-Induced B16F10 Cells Via the Antimelanogenesic Effect of Eicosenoic Acid

Melanogenesis is a complex process that can lead to pigmentation defects. Various chemical skin-lightening products have been developed to treat pigmentation disorders. However, these chemical products can cause harmful adverse effects. Therefore, the development of safer, natural bleaching ingredients is a trend for sustainability. It has been reported that unsaturated fatty acids exhibit significant antimelanogenic effects. Sapindus mukorossi seed oils contain abundant unsaturated fatty acids; however, these have not yet been investigated for beneficial effects on skin tone evenness. In this study, we tested the possibility of using S. mukorossi oil for the treatment of hyperpigmentation in an in vitro model. Free fatty acid compositions and β-sitosterol were determined by gas chromatography-mass spectrometry and high-pressure liquid chromatography, respectively. The effect of S. mukorossi oil on melanoma B16F10 cell viability was detected using the 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl-tetrazolium bromide assay. The inhibitive effects of fatty acids and β-sitosterol in S. mukorossi oil on α-melanocyte-stimulating hormone (MSH)-induced melanogenesis was evaluated by detecting melanin formation and tyrosinase activity. Our results showed that S. mukorossi oil produced no significant cytotoxicity in B16F10 cells at various concentrations compared with the control group. The enhancement of melanin formation induced by α-MSH was reduced by S. mukorossi oil. We also found that the primary fatty acid contributing to the antimelanogenesis effect was eicosenoic acid. These results suggest that S. mukorossi seed oil can effectively inhibit melanogenesis and has the potential for future development as a de-hyperpigmentation product within a waste utilization context.

Mercury Exposure Associated with Use of Skin Lightening Products in Jamaica

BACKGROUND

Skin bleaching is a major health concern among Jamaicans. A common ingredient in skin lightening products is mercury. Mercury is a toxic substance that can cause damage to the gastrointestinal tract, nervous system and kidneys.

OBJECTIVE

The objectives of this study were to use different analytical techniques to measure mercury concentrations in popular skin lightening products used in Jamaica and to assess individual levels of mercury exposure based on product usage.

METHODS

Sixty skin lightening products were purchased from different vendors across various locations in Jamaica. Each product was initially screened for mercury using a portable handheld energy dispersive X-ray fluorescence (XRF) analyzer. In addition, 25 out of 60 products were further measured using cold vapor atomic absorption spectroscopy (CVAAS). Questionnaires were distributed to users of skin lightening products to determine their usage patterns.

RESULTS

Six products had mercury concentrations above the United States Food and Drug Administration (FDA) allowable limit of 1 ppm, of which three products contained alarmingly high concentrations (i.e. > 400 ppm). The majority of products (57 out of 60) had mercury concentrations below 10 ppm. The mercury concentrations in skin lightening products ranged from 0.05 ppm to 17,547 ppm. In our sample, 51% of women and 49% of men used skin products more than once per day.

CONCLUSIONS

On average, creams contained more mercury than lotions and soaps. Individuals who use skin lightening products in Jamaica may be at risk for high mercury exposure, as some popular products were found to have mercury concentrations above the allowable limit.

COMPETING INTERESTS

The authors declare no competing financial interests.

The study of inhibitory effects and mechanism of carboxylate chitooligomer on melanin, prepared by laccase/TEMPO system

A carboxylate chitooligomer (C-COS) containing carboxyl groups attached to chitooligomer (COS) molecules has been prepared by laccase/2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) system, which is a green-chemistry method. Several experiments were designed to evaluate inhibition effects on melanin and mechanisms of C-COS. The results indicated that C-COS exhibited more distinct anti-melanogenic effects compared to COS. C-COS inhibits melanin production with tyrosine (Tyr) and DOPA as the substrate of melanin formation, and the inhibition rates are, respectively, 89.07% and 84.45%, which reach 1.4-2 times those of COS. UV-vis spectroscopy was used to elucidate the interaction mechanism between C-COS and tyrosinase (TYR). It is C-COS chelating with metal Cu ions in tyrosinase (TYR) that decreases the enzyme activity. Half-maximal inhibitory concentrations (IC₅₀) of C-COS were calculated as 13.49 and 4.07 mg/mL for monophenolase (cresolase) and diphenolase (catecholase), respectively.

Neurodevelopmental Effects of Mercury

The toxicology of mercury (Hg) is of concern since this metal is ubiquitously distributed in the environment, and living organisms are routinely exposed to Hg at low to high levels. The toxic effects of Hg are well studied and it is known that they may differ depending on the Hg chemical species. In this chapter, we emphasize the neurotoxic effects of Hg during brain development. The immature brain is more susceptible to Hg exposure, since all the Hg chemical forms, not only the organic ones, can harm it. The possible consequences of Hg exposure during the early stages of development, the additive effects with other co-occurring neurotoxicants, and the known mechanisms of action and targets will be addressed in this chapter.

Skin Color, Cultural Capital, and Beauty Products: An Investigation of the Use of Skin Fairness Products in Mumbai, India

The use of skin fairness products that frequently contain toxic ingredients is associated with significant adverse health side effects. Due to the high prevalence of use in Asian and African countries, skin fairness product use is recognized as a growing public health concern. The multi-million-dollar skin fairness product industry has also been criticized for perpetuating racism and social inequalities by reinforcing beliefs about the benefits of skin fairness for cultural capital. No quantitative studies have assessed people’s beliefs about fairness and reasons for using or not using these products in India, one of the largest global markets for skin fairness products. The current study explored skin fairness product use among 1,992 women and men aged 16–60 years in the city of Mumbai, India using a self-report questionnaire. A total of 37.6% of the sample reported currently using skin fairness products, with women being two times more likely to use these products. Among current users, 17% reported past experiences of adverse side effects, and “Media/TV/Adverts” were the most common prompts for using fairness products, followed by “Friends” and “Family.” Men were significantly more likely than women to endorse beliefs about fairness being more attractive and were more likely to perceive family and peers as viewing fairness as beneficial for cultural capital. There were no differences between women and men currently using products in their desire to look as fair as media celebrities. Among non-users, women were significantly more likely than men to report concerns about product efficacy and side effects as reasons for non-use, while men were significantly more likely to report socioeconomic reasons for non-use. Implications of these findings are discussed in light of growing public health concerns about the use of fairness products, and potential for advocacy and public health interventions to address the use of skin fairness products.

The environmental injustice of beauty: framing chemical exposures from beauty products as a health disparities concern

The obstetrics-gynecology community has issued a call to action to prevent toxic environmental chemical exposures and their threats to healthy human reproduction. Recent committee opinions recognize that vulnerable and underserved women may be impacted disproportionately by environmental chemical exposures and recommend that reproductive health professionals champion policies that secure environmental justice. Beauty product use is an understudied source of environmental chemical exposures. Beauty products can include reproductive and developmental toxicants such as phthalates and heavy metals; however, disclosure requirements are limited and inconsistent. Compared with white women, women of color have higher levels of beauty product-related environmental chemicals in their bodies, independent of socioeconomic status. Even small exposures to toxic chemicals during critical periods of development (such as pregnancy) can trigger adverse health consequences (such as impacts on fertility and pregnancy, neurodevelopment, and cancer). In this commentary, we seek to highlight the connections between environmental justice and beauty product-related chemical exposures. We describe racial/ethnic differences in beauty product use (such as skin lighteners, hair straighteners, and feminine hygiene products) and the potential chemical exposures and health risks that are associated with these products. We also discuss how targeted advertising can take advantage of mainstream beauty norms to influence the use of these products. Reproductive health professionals can use this information to advance environmental justice by being prepared to counsel patients who have questions about toxic environmental exposures from beauty care products and other sources. Researchers and healthcare providers can also promote health-protective policies such as improved ingredient testing and disclosure for the beauty product industry. Future clinical and public health research should consider beauty product use as a factor that may shape health inequities in women's reproductive health across the life course.