Open AccessArticle
Topical Retinol Restores Type I Collagen Production in Photoaged Forearm Skin within Four Weeks
Cosmetics 2016, 3(4), 35; doi:10.3390/cosmetics3040035 -
Abstract
Production of type I collagen (COL1), the major structural protein of the skin, declines during aging, leading to skin thinning and becoming fragile, which increases the risk of bruising and wound healing disorders in the elderly. Topical treatments that can restore COL1 [...] Read more.
Production of type I collagen (COL1), the major structural protein of the skin, declines during aging, leading to skin thinning and becoming fragile, which increases the risk of bruising and wound healing disorders in the elderly. Topical treatments that can restore COL1 synthesis and ultimately COL1 content in aged skin hold promise to improve skin health. Much effort has been spent on developing agents that can safely and effectively enhance COL1 synthesis in aged skin. However, how fast and to what extent COL1 production in aged skin can be enhanced by a topical treatment remains unclear. Herein, we investigated a four-week topical retinol (ROL) treatment. A one-day occlusion of ROL (0.4%) or vehicle was applied on photoaged forearms of elderly (>65 years old) subjects once a week for four weeks. Vehicle was also applied on forearms of young (23–33 years) subjects in the same manner. Skin samples were obtained one week after the last treatment and analyzed for COL1 synthesis. We found that the ROL treatment increased the level of COL1 mRNA (2.3-fold) and proCOL1 protein (1.8-fold) in photoaged forearms to levels similar to that of young forearms within four weeks. Our study proves the concept that reduced COL1 production in aged skin can be readily restored. In addition, our study provides an evidence-based foundation for developing COL1-enhancing topical agents, and establishes a reliable and practical efficacy test for evaluating such agents. Full article
Figures

Figure 1

Open AccessReview
Essential of Hair Care Cosmetics
Cosmetics 2016, 3(4), 34; doi:10.3390/cosmetics3040034 -
Abstract
Nowadays, hair care and style play a very important role in people’s physical aspect and self-perception. Hair cosmetics can be distinguished into two main categories: cosmetics with temporary effect on the hair, for example shampoos, conditioners, sprays, and temporary colors; and cosmetics [...] Read more.
Nowadays, hair care and style play a very important role in people’s physical aspect and self-perception. Hair cosmetics can be distinguished into two main categories: cosmetics with temporary effect on the hair, for example shampoos, conditioners, sprays, and temporary colors; and cosmetics with permanent effect on the hair, such as permanent waves, relaxers, bleaches and permanent colors. These cosmetic procedures may induce hair abnormalities. We provide an overview on the most important characteristics of these procedures, analyzing components and effects on the hair. Finally, we evaluated new camouflage techniques and tattoo scalp. Full article
Figures

Figure 1

Open AccessReview
A Fairer Face, a Fairer Tomorrow? A Review of Skin Lighteners
Cosmetics 2016, 3(3), 33; doi:10.3390/cosmetics3030033 -
Abstract
From light-skinned deities depicted in ancient religious tableaux, pearl-swallowing practices in China, turmeric ceremonies in India to clay application in Africa, history has been coloured by our questionable aversion to the darker shades. Complexion has assumed psychological, economic and political currency with [...] Read more.
From light-skinned deities depicted in ancient religious tableaux, pearl-swallowing practices in China, turmeric ceremonies in India to clay application in Africa, history has been coloured by our questionable aversion to the darker shades. Complexion has assumed psychological, economic and political currency with continued growth in the desire for skin lighteners sweeping the boundaries of country, race, cultural and socioeconomic status. This review explores our early associations with the symbolism of colour through religion, the ideals of complexion across cultures and time, the motivations behind the use of skin lightening practices, and the use of colour within political and economic agendas. Skin-lightening agents with regard to content, adverse effect profile and regulation are discussed and safe skin care practices in assisting with an individual’s adoption of a more tolerable spectrum of shades are alluded to. Full article
Figures

Figure 1

Open AccessArticle
Packaging Evaluation Approach to Improve Cosmetic Product Safety
Cosmetics 2016, 3(3), 32; doi:10.3390/cosmetics3030032 -
Abstract
In the Regulation 1223/2009, evaluation of packaging has become mandatory to assure cosmetic product safety. In fact, the safety assessment of a cosmetic product can be successfully carried out only if the hazard deriving from the use of the designed packaging for [...] Read more.
In the Regulation 1223/2009, evaluation of packaging has become mandatory to assure cosmetic product safety. In fact, the safety assessment of a cosmetic product can be successfully carried out only if the hazard deriving from the use of the designed packaging for the specific product is correctly evaluated. Despite the law requirement, there is too little information about the chemical-physical characteristics of finished packaging and the possible interactions between formulation and packaging; furthermore, different from food packaging, the cosmetic packaging is not regulated and, to date, appropriate guidelines are still missing. The aim of this work was to propose a practical approach to investigate commercial polymeric containers used in cosmetic field, especially through mechanical properties’ evaluation, from a safety point of view. First of all, it is essential to obtain complete information about raw materials. Subsequently, using an appropriate full factorial experimental design, it is possible to investigate the variables, like polymeric density, treatment, or type of formulation involved in changes to packaging properties or in formulation-packaging interaction. The variation of these properties can greatly affect cosmetic safety. In particular, mechanical properties can be used as an indicator of pack performances and safety. As an example, containers made of two types of polyethylene with different density, low-density polyethylene (LDPE) and high-density polyethylene (HDPE), are investigated. Regarding the substances potentially extractable from the packaging, in this work the headspace solid-phase microextraction method (HSSPME) was used because this technique was reported in the literature as suitable to detect extractables from the polymeric material here employed. Full article
Figures

Figure 1

Open AccessEditorial
Special Issue “Cosmetic Contact Allergens”
Cosmetics 2016, 3(3), 31; doi:10.3390/cosmetics3030031 -
Abstract
In Europe, a cosmetic is defined as any substance or preparation intended to be placed in contact with the various external parts of the human body (epidermis, hair system, nails, lips and external genital organs) or with the teeth and the mucous [...] Read more.
In Europe, a cosmetic is defined as any substance or preparation intended to be placed in contact with the various external parts of the human body (epidermis, hair system, nails, lips and external genital organs) or with the teeth and the mucous membranes of the oral cavity with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance and/or correcting body odours and/or protecting them or keeping them in good condition.[...] Full article
Open AccessReview
Endeavors in the Area of Hair Care—Chemical Aspects of Hair Care Processes and Products
Cosmetics 2016, 3(3), 30; doi:10.3390/cosmetics3030030 -
Abstract
The paper focuses on historical review of explorations and progress in the field of hair care. The descriptive theme of the survey is accompanied by references to specific investigations of the structure and physico-chemical properties of hair that are essential for evolving [...] Read more.
The paper focuses on historical review of explorations and progress in the field of hair care. The descriptive theme of the survey is accompanied by references to specific investigations of the structure and physico-chemical properties of hair that are essential for evolving of novel processes and products. Full article
Figures

Figure 1

Open AccessReview
Contact Allergy to Preservatives—Is the European Commission a Commendable Risk Manager?
Cosmetics 2016, 3(3), 29; doi:10.3390/cosmetics3030029 -
Abstract
Although preservatives are necessary to prevent deterioration by microbial growth in cosmetic products, daily skin contact with preserved cosmetic products may cause a preservative contact allergy. Only preservatives with sufficient pre-market risk assessment, presumably being safe for the consumer from a public [...] Read more.
Although preservatives are necessary to prevent deterioration by microbial growth in cosmetic products, daily skin contact with preserved cosmetic products may cause a preservative contact allergy. Only preservatives with sufficient pre-market risk assessment, presumably being safe for the consumer from a public health point of view, are permitted for use in cosmetic products in the European Union. Notwithstanding the efforts by the European Commission (EC) to avoid epidemics of contact allergy, the former epidemic of contact allergy to methyldibromo glutaronitrile and the unprecedented epidemic of contact allergy to methylisothiazolinone show the procrastination of the European Union risk management process for cosmetic ingredients. Timely risk management is of the utmost importance to avoid rapidly increasing numbers of contact allergy to turn into full-blown epidemics. It is therefore proposed that in order to avoid future epidemics of contact allergy to preservatives, the allowed preservatives in cosmetic products should be entered onto Annex V on a time-limited basis only, and they must be re-evaluated in order to stay on Annex V. Full article
Open AccessReview
Oxidative Stress and Human Skin Connective Tissue Aging
Cosmetics 2016, 3(3), 28; doi:10.3390/cosmetics3030028 -
Abstract
Everyone desires healthy and beautiful-looking skin. However, as we age, our skin becomes old due to physiological changes. Reactive oxygen species (ROS) is an important pathogenic factor involved in human aging. Human skin is exposed to ROS generated from both extrinsic sources [...] Read more.
Everyone desires healthy and beautiful-looking skin. However, as we age, our skin becomes old due to physiological changes. Reactive oxygen species (ROS) is an important pathogenic factor involved in human aging. Human skin is exposed to ROS generated from both extrinsic sources such as as ultraviolet (UV) light from the sun, and intrinsic sources such as endogenous oxidative metabolism. ROS-mediated oxidative stress damages the collagen-rich extracellular matrix (ECM), the hallmark of skin connective tissue aging. Damage to dermal collagenous ECM weakens the skin’s structural integrity and creates an aberrant tissue microenvironment that promotes age-related skin disorders, such as impaired wound healing and skin cancer development. Here, we review recent advances in our understanding of ROS/oxidative stress and skin connective tissue aging. Full article
Open AccessReview
Human Hair and the Impact of Cosmetic Procedures: A Review on Cleansing and Shape-Modulating Cosmetics
Cosmetics 2016, 3(3), 26; doi:10.3390/cosmetics3030026 -
Abstract
Hair can be strategically divided into two distinct parts: the hair follicle, deeply buried in the skin, and the visible hair fiber. The study of the hair follicle is mainly addressed by biological sciences while the hair fiber is mainly studied from [...] Read more.
Hair can be strategically divided into two distinct parts: the hair follicle, deeply buried in the skin, and the visible hair fiber. The study of the hair follicle is mainly addressed by biological sciences while the hair fiber is mainly studied from a physicochemical perspective by cosmetic sciences. This paper reviews the key topics in hair follicle biology and hair fiber biochemistry, in particular the ones associated with the genetically determined cosmetic attributes: hair texture and shape. The traditional and widespread hair care procedures that transiently or permanently affect these hair fiber features are then described in detail. When hair is often exposed to some particularly aggressive cosmetic treatments, hair fibers become damaged. The future of hair cosmetics, which are continuously evolving based on ongoing research, will be the development of more efficient and safer procedures according to consumers’ needs and concerns. Full article
Figures

Open AccessReview
Overview of Skin Whitening Agents: Drugs and Cosmetic Products
Cosmetics 2016, 3(3), 27; doi:10.3390/cosmetics3030027 -
Abstract
Depigmentation and skin lightening products, which have been in use for ages in Asian countries where skin whiteness is a major esthetic criterion, are now also highly valued by Western populations, who expose themselves excessively to the sun and develop skin spots [...] Read more.
Depigmentation and skin lightening products, which have been in use for ages in Asian countries where skin whiteness is a major esthetic criterion, are now also highly valued by Western populations, who expose themselves excessively to the sun and develop skin spots as a consequence. After discussing the various possible mechanisms of depigmentation, the different molecules that can be used as well as the status of the products containing them will now be presented. Hydroquinone and derivatives thereof, retinoids, alpha- and beta-hydroxy acids, ascorbic acid, divalent ion chelators, kojic acid, azelaic acid, as well as diverse herbal extracts are described in terms of their efficacy and safety. Since a genuine effect (without toxic effects) is difficult to obtain, prevention by using sunscreen products is always preferable. Full article
Figures

Open AccessArticle
Experiences and Statistical Evaluation of Serious Undesirable Effects of Cosmetic Products in the EU
Cosmetics 2016, 3(3), 25; doi:10.3390/cosmetics3030025 -
Abstract
The Council of Europe created an outline for a vigilant system of undesirable effects of cosmetic products in 2006. In 2013, some of those aspects were included in the European Cosmetics Regulation (EC) 1223/2009. Since then, serious undesirable effects (SUEs), which are [...] Read more.
The Council of Europe created an outline for a vigilant system of undesirable effects of cosmetic products in 2006. In 2013, some of those aspects were included in the European Cosmetics Regulation (EC) 1223/2009. Since then, serious undesirable effects (SUEs), which are the tip of the iceberg of all undesirable effects of cosmetic products, have to be reported to competent authorities. Neglecting the first phase of establishing the system, we have about two years of experience regarding the notification of SUEs. This notification system is based on a huge amount of cases that allow us to identify occurring problems at an early stage through a signal of increased reported cases for a certain product. It has already been shown that the system is able to identify products that have the potential to cause health risks even if they seem to comply with the legal requirements and the safeguard clause was applied. Until May 2016, 680 cases of SUEs were shared in the EU. The statistics of SUEs indicate that hair dyes and skin care products are the product types that cause the most SUEs. Almost 80% of all SUEs occurred in the head area, especially the skin of the face was affected. Full article
Open AccessArticle
Facial Skin Lifting and Brightening Following Sleep on Copper Oxide Containing Pillowcases
Cosmetics 2016, 3(3), 24; doi:10.3390/cosmetics3030024 -
Abstract
Copper plays a key role in many of the physiological processes that occur in the skin. Previously it was found that sleeping on pillowcases impregnated with microscopic copper oxide particles results in reduction of wrinkles and fine lines. In the current study, [...] Read more.
Copper plays a key role in many of the physiological processes that occur in the skin. Previously it was found that sleeping on pillowcases impregnated with microscopic copper oxide particles results in reduction of wrinkles and fine lines. In the current study, it was examined if sleeping on copper oxide impregnated pillowcases results also in skin lifting and skin brightness. A four week, double blind, randomized study was performed, during which 45 women, aged 37–54, slept on copper oxide containing pillowcases (test group, n = 23) or on control pillowcases without copper oxide (control group, n = 22). Facial and eye skin surface was measured using an F-ray 3D measurement system and surface analysis was conducted using Image-pro® plus. Skin brightness was measured using a tristimulus colorimeter. Sleeping on the test pillowcases resulted in statistically significant skin lifting on the cheek area (p = 0.039) and eye area (p = 0.001) after four weeks of use as compared to baseline. The mean skin brightness in those sleeping on the test pillowcases increased after two (p = 0.024) and four weeks (p = 0.008). No statistically significant changes occurred during the study in the study participants using the control pillowcases. Statistically significant differences between both groups were recorded at two and four weeks for skin brightness and skin lifting, respectively. In conclusion, sleeping on copper oxide containing pillowcases results in facial skin lifting and brightness of the skin. Full article
Figures

Open AccessCase Report
Sensitization and Clinically Relevant Allergy to Hair Dyes and Clothes from Black Henna Tattoos: Do People Know the Risk? An Uncommon Serious Case and a Review of the Literature
Cosmetics 2016, 3(3), 23; doi:10.3390/cosmetics3030023 -
Abstract
Henna (Lawsonia inermis L.) tattooing has been used in Egypt and India since ancient times. Today this temporary body art is becoming increasingly popular among young people. Various chemicals are added to henna to darken and enhance the definition of tattoos, [...] Read more.
Henna (Lawsonia inermis L.) tattooing has been used in Egypt and India since ancient times. Today this temporary body art is becoming increasingly popular among young people. Various chemicals are added to henna to darken and enhance the definition of tattoos, especially para-phenylenediamine (PPD), which is a strong sensitizer known to cause cross sensitive reactions to azoic dyes and other para-amino compounds. We present the case of an 18-year-old girl who became clinically sensitive to textile dyes after having showed a serious reaction both to her first hair dying when she was 16 years old and following the application of a temporary henna tattoo when she was a kid. The evidence from our literature review showed 33 cases of manifest sensitization to hair dye and only one of observable contact allergy to both hair and textile dyes from henna tattoos. The sensitization of children may have long-life lasting consequences, because of cross-reaction to dyes and other chemicals contained in hair colourants, clothes and drugs. Since tattoos are very popular and globalization has increased the circulation of unauthorized products we point out the need for informative campaigns about the risk of sensitization caused by temporary tattoos. Full article
Open AccessReview
Mushroom Cosmetics: The Present and Future
Cosmetics 2016, 3(3), 22; doi:10.3390/cosmetics3030022 -
Abstract
Mushrooms have been valued as a traditional source of natural bioactive compounds for centuries and have recently been exploited for potential components in the cosmetics industry. Numerous mushrooms and their ingredients have been known to be beneficial to the skin and hair. [...] Read more.
Mushrooms have been valued as a traditional source of natural bioactive compounds for centuries and have recently been exploited for potential components in the cosmetics industry. Numerous mushrooms and their ingredients have been known to be beneficial to the skin and hair. The representative ingredients are as follows: phenolics, polyphenolics, terpenoids, selenium, polysaccharides, vitamins, and volatile organic compounds. These compounds show excellent antioxidant, anti-aging, anti-wrinkle, skin whitening, and moisturizing effects, which make them ideal candidates for cosmetics products. This review provides some perspectives of mushrooms (and/or extracts) and their ingredients presently used, or patented to be used, in both cosmeceuticals for topical administration and nutricosmetics for oral administration. With the small percentage of mushrooms presently identified and utilized, more mushroom species will be discovered, verified, and cultivated in the future, boosting the development of relevant industry. Combining with progress in genomics, proteomics, metabolomics, and systems pharmacology, mushrooms can find their way into cosmetics with multiple approaches. Full article
Open AccessReview
Contact Allergy to Hair Dyes
Cosmetics 2016, 3(3), 21; doi:10.3390/cosmetics3030021 -
Abstract
Many strong and extreme sensitizing chemicals, such as para-phenylenediamine (PPD), toluene-2,5-diamine (TDA) and other aromatic amines or cross-reacting substances, are ingredients in hair dye products. The chemistry of hair dyeing and the immunological reactions to the potent sensitizing hair dye components are [...] Read more.
Many strong and extreme sensitizing chemicals, such as para-phenylenediamine (PPD), toluene-2,5-diamine (TDA) and other aromatic amines or cross-reacting substances, are ingredients in hair dye products. The chemistry of hair dyeing and the immunological reactions to the potent sensitizing hair dye components are complex and have not been fully clarified up until now. Recently 2-methoxymethyl-p-phenylenediamine (ME-PPD), a PPD derivate with moderate skin-sensitizing properties, was developed. Although developed for the prevention of sensitization, ME-PPD appears to be tolerated in some PPD/TDA-allergic individuals. Full article
Open AccessArticle
An Overview of Trials´Accreditation and Recognition of Brazilian Tests Used for the Safety Evaluation of Cosmetic Products
Cosmetics 2016, 3(2), 20; doi:10.3390/cosmetics3020020 -
Abstract
For some time, Brazil has been appointed as one of the greatest consumers of cosmetic products in the world. Although cosmetics may seem harmless, destined exclusively to enhance personal appearance or to clean and protect the skin, hair and nails, new studies [...] Read more.
For some time, Brazil has been appointed as one of the greatest consumers of cosmetic products in the world. Although cosmetics may seem harmless, destined exclusively to enhance personal appearance or to clean and protect the skin, hair and nails, new studies and events are highlighting the need to evaluate the safety of such products. The present work interrelated the lifecycle of a cosmetic product with the safety trials and tests applicable to some cycle phases. From this information, a survey was made of accredited Conformity Assessment Bodies (CAB) and test facilities recognized by the General Coordination for Accreditation (CGCRE) which are competent respectively to carry out safety trials and tests of cosmetics. Twenty five competent laboratories were identified to carry out chemical and/or biological trials of cosmetics, according to the legislation ABNT ISO IEC 17025:2005, and 10 test facilities recognized by the Compliance Monitoring Program that can carry out tests of the development of a product for register purposes, aiming at human health and safety. It is interesting to notice that Brazil has accredited laboratories to carry out trials that are critical for the health of the population, such as the levels of heavy metals and the presence of pathogens. On the other hand, CGCRE does not have a program to recognize safety clinical trials. The importance of this kind of study is understood, considering the world history of adverse reactions and the great consumption of cosmetics in the country. Full article
Open AccessReview
Fragrance Allergens, Overview with a Focus on Recent Developments and Understanding of Abiotic and Biotic Activation
Cosmetics 2016, 3(2), 19; doi:10.3390/cosmetics3020019 -
Abstract
Fragrances and fragranced formulated products are ubiquitous in society. Contact allergies to fragrance chemicals are among the most common findings when patch-testing patients with suspected allergic contact dermatitis, as well as in studies of contact allergy in the general population. The routine [...] Read more.
Fragrances and fragranced formulated products are ubiquitous in society. Contact allergies to fragrance chemicals are among the most common findings when patch-testing patients with suspected allergic contact dermatitis, as well as in studies of contact allergy in the general population. The routine test materials for diagnosing fragrance allergy consist mainly of established mixes of fragrance compounds and natural extracts. The situation is more complex as several fragrance compounds have been shown to be transformed by activation inside or outside the skin via abiotic and/or biotic activation, thus increasing the risk of sensitization. For these fragrance chemicals, the parent compound is often non-allergenic or a very weak allergen, but potent sensitizers will be formed which can cause contact allergy. This review shows a series of fragrance chemicals with well-documented abiotic and/or biotic activation that are indicative and illustrative examples of the general problem. Other important aspects include new technologies such as ethosomes which may enhance both sensitization and elicitation, the effect on sensitization by the mixtures of fragrances found in commercial products and the effect of antioxidants. A contact allergy to fragrances may severely affect quality of life and many patients have multiple allergies which further impact their situation. Further experimental and clinical research is needed to increase the safety for the consumer. Full article
Open AccessReview
Anti-Melanogenesis Effect of Quercetin
Cosmetics 2016, 3(2), 18; doi:10.3390/cosmetics3020018 -
Abstract
Whitening cosmetics with anti-melanogenesis activity are very popular worldwide. Many companies have tried to identify novel ingredients that show anti-melanogenesis effects for new product development. Among many plant-derived compounds, polyphenols are thought to be one of the most promising anti-melanogenesis ingredients. In [...] Read more.
Whitening cosmetics with anti-melanogenesis activity are very popular worldwide. Many companies have tried to identify novel ingredients that show anti-melanogenesis effects for new product development. Among many plant-derived compounds, polyphenols are thought to be one of the most promising anti-melanogenesis ingredients. In order to prepare effective whitening polyphenols, 3,3,4,5,7-pentahydrosyflavone (quercetin) has been widely researched and applied to commercial products because it is present in high levels in many edible plants. Quercetin is thus a representative polyphenol and has recently gained attention in the cosmetics field. There are many controversies, however, regarding the effect of quercetin, based on in vitro studies, cell line experiments, and human trials. In this review, toxicity and efficacy data for quercetin and its derivatives in various experimental conditions (i.e., various cell lines, concentration ranges, and other parameters) were examined. Based on this analysis, quercetin itself is shown to be ineffective for hypopigmentation of human skin. However, a few types of quercetin derivatives (such as glycosides) show some activity in a concentration-dependent manner. This review provides clarity in the debate regarding the effects of quercetin. Full article
Open AccessReview
Legislative Aspects of Cosmetic Safety in the European Union: The Case of Contact Allergy
Cosmetics 2016, 3(2), 17; doi:10.3390/cosmetics3020017 -
Abstract
For several decades, the European Union (EU) has amongst its many tenets and principles the aim, enshrined in an EU Directive, that cosmetic products should not cause harm to the consumer. To a great extent, this is been successful, although it is [...] Read more.
For several decades, the European Union (EU) has amongst its many tenets and principles the aim, enshrined in an EU Directive, that cosmetic products should not cause harm to the consumer. To a great extent, this is been successful, although it is noteworthy that the frequency of contact allergy to a number of ingredients commonly found in cosmetics has remained stubbornly high. Perhaps because of this, but certainly because of the drive by the European Commission towards better, more streamlined, regulation, the Directive was recast into a Regulation, usually referred to as the EU Cosmetics Regulation ((EC) No 1223/2009). As with the Directive, for each and every cosmetic product placed on the consumer market in the EU, a safety assessment is required. The Regulation requires that a dossier is prepared detailing the composition of the product, the safety of each of its ingredients, as well as an evaluation of overall product safety. This has to be completed by suitably trained and qualified assessors. Also relevant to cosmetic products are the general regulations pertaining to chemicals used in the EU where again many details of the toxicological profile must be ascertained and reviewed. On this basis, it should be possible to ensure that the extent of contact allergy attributed to cosmetic products declines. However, legislation is one thing, but it is also necessary to ensure that the cosmetic industry safety assessment process is completed in a rigourous manner (or even done at all) and that demands enforcement of the legislation. Full article
Open AccessReview
Integrated Testing Strategies for Skin Sensitization Hazard and Potency Assessment—State of the Art and Challenges
Cosmetics 2016, 3(2), 16; doi:10.3390/cosmetics3020016 -
Abstract
The paper provides an overview of existing Integrated Testing Strategies (ITS) for assessing hazard and potency of skin sensitization. The ITS research is active, diverse and constantly evolving as new assays are being developed and new mechanistic insights are discovered. Despite the [...] Read more.
The paper provides an overview of existing Integrated Testing Strategies (ITS) for assessing hazard and potency of skin sensitization. The ITS research is active, diverse and constantly evolving as new assays are being developed and new mechanistic insights are discovered. Despite the need to assess potency, the majority of the ITS approaches developed to date assess hazard only. Reasons for this situation are analyzed and include, for example, the dynamic range of existing alternative assays versus the range of in vivo responses, but also sporadic use of kinetic information and molar units. Depending on the application, regulatory or product development, standardized and nonstandard ITS approaches will be developed. Challenges to practical applications, with focus on regulatory are discussed. Full article