Bakuchiol-A new allergen in cosmetics

In a Preliminary Study on Human Subjects, a Cosmetic Cream Containing a Harungana madagascariensis Plant Extract Induces Similar Anti-Aging Effects to a Retinol-Containing Cream

Retinoids are the most effective anti-aging ingredients. Yet, their use can result in adverse reactions. Even bakuchiol, a natural functional analog, can lead to contact dermatitis. We previously showed that a Harungana madagascariensis (Lam. ex Poir.) plant extract (HME) presents retinol-like properties in vitro. Therefore, we performed a preliminary analysis of the anti-aging potential of a cream containing HME on 46 subjects. The participants applied a HME cream on half of their face and one forearm. The effects induced were compared to those produced by a retinol cream applied to the contralateral side. Clinical evaluations indicate that the two creams rapidly (28 days) improve wrinkles underneath the eyes, ptosis, color homogeneity, smoothness, plumpness, firmness, and elasticity of the facial skin. The improvement of crow's feet is only significant after 56 days. For all clinical signs, the effects of both creams are indistinguishable. Instrumental measurements of silicon replica from the eye contour region indicate that the wrinkle surface reduction is already noticeable after 28 days with the HME and retinol cream, while it takes 56 days to have a significant depth decrease. Only the retinol cream improves wrinkle length after 56 days. Ultrasound assessment of forearm skin revealed that the HME cream improves superficial dermis density as early as 28 days with further improvement at day 56, timepoint at which improvement is at the limit of significance with the retinol cream. These preliminary results indicate that HME has similar in vivo functional properties to retinol for reducing the severity of aging signs. Future works, including a bona fide clinical study, are needed to confirm these findings.

Contact Allergy-Emerging Allergens and Public Health Impact

Contact allergy (sensitisation) and allergic contact dermatitis (ACD) resulting from it have a considerable public health impact. For the present review, all pertinent articles were systematically searched via Medline and Web of Science™; additionally, all available issues of the journals "Contact Dermatitis" and "Dermatitis" were manually searched, covering the years 2018-2019, thereby extending and re-focusing a previous similar review. New allergens, or previously described allergens found in a new exposure context or of other current importance, are described in sections according to substance classes, e.g., metals, preservatives, fragrances. As a common finding in many investigations, a lack of information on product composition has been noted, for instance, regarding a newly described allergen in canvas shoes (dimethylthiocarbamylbenzothiazole sulfide) and, most notably, absence of co-operation from manufacturers of glucose-monitoring devices and insulin pumps, respectively. These latter devices have been shown to cause severe ACD in a considerable number of diabetic patients caused by the liberation of isobornyl acrylate and N,N'-dimethylacrylamide, respectively, as demonstrated by an international collaboration between dermatologists and chemists. Improved and complete ingredient labelling for all types of products, and not just cosmetics, must be put on the legislative agenda.