Patch Test Reactions Associated With Sunscreen Products and the Importance of Testing to an Expanded Series: Retrospective Analysis of North American Contact Dermatitis Group Data, 2001 to 2010

Sunscreens part 2: Regulation and safety

The second part of this CME article discusses sunscreen regulation and safety considerations for humans and the environment. First, we provide an overview of the history of the US Food and Drug Administration's regulation of sunscreen. Recent Food and Drug Administration studies clearly demonstrate that organic ultraviolet filters are systemically absorbed during routine sunscreen use, but to date there is no evidence of associated negative health effects. We also review the current evidence of sunscreen's association with vitamin D levels and frontal fibrosing alopecia, and recent concerns regarding benzene contamination. Finally, we review the possible environmental effects of ultraviolet filters, particularly coral bleaching. While climate change has been shown to be the primary driver of coral bleaching, laboratory-based studies suggest that organic ultraviolet filters represent an additional contributing factor, which led several localities to ban certain organic filters.

Body dissatisfaction widens the racial disparities of Benzophenone-3, a chemical biomarker of personal care and consumer product usage

Background

Body dissatisfaction can drive individuals to use personal care products, exposing themselves to Benzophenone-3 (BP3). Yet, no study has examined the link between body dissatisfaction and elevated chemical exposures.

Objectives

Our study examines how body dissatisfaction impacts the racial differences in BP3 exposures.

Methods

Using NHANES 2003-2016 data for 3,072 women, we ascertained body dissatisfaction with a questionnaire on weight perception. We ran two generalized linear models with log10-transformed urinary concentrations of BP3 as the outcome variable and the following main predictors: one with race/ethnicity and another combining race/ethnicity and body dissatisfaction. We also conducted stratified analyses by race/ethnicity. We adjusted for poverty income ratio, BMI, urinary creatinine, and sunscreen usage.

Results

BP3 levels in Mexican American, Other Hispanic, Other Race, non-Hispanic White, and non-Hispanic Asian women were on average 59%, 56%, 33%, 16%, and 9% higher, respectively, compared to non-Hispanic Black women. Racial differences in BP3 levels are accentuated with body dissatisfaction. For example, Other Hispanic women perceiving themselves as overweight had 69% higher BP3 levels than non-Hispanic Black women (p-value = 0.01), while those perceiving themselves as at the right weight had 32% higher levels (p-value = 0.31). Moreover, minority women perceiving themselves as overweight tended to have higher BP3 levels than those who do not. For example, BP3 levels in Other Hispanic women perceiving themselves as overweight are significantly higher compared to those who do not (73%, p-value = 0.03). In contrast, such differences in the non-Hispanic White women are minimal (-0.5%, p-value = 0. 98).

Discussion

Minority women with body dissatisfaction show elevated BP3 exposure independent of sunscreen usage, implying that their elevated exposures may stem from using other personal care and consumer products. Further research is needed to determine if increases of exposure to potential toxicants occur among minority women with body dissatisfaction.

A review of sources, pathways, and toxic effects of human exposure to benzophenone ultraviolet light filters

Benzophenone ultraviolet light filters (BPs) are high-production-volume chemicals extensively used in personal care products, leading to widespread human exposure. Given their estrogenic properties, the potential health risks associated with exposure to BPs have become a public health concern. This review aims to summarize sources and pathways of exposure to BPs and associated health risks. Dermal exposure, primarily through the use of sunscreens, constitutes a major pathway for BP exposure. At a recommended application rate, dermal exposure of BP-3 via the application of sunscreens may reach or exceed the suggested reference dose. Other exposure pathways to BPs, such as drinking water, seafood, and packaged foods, contribute minimal to the overall dose. Inhalation is a minor pathway of exposure; however, its contribution cannot be ignored. Human exposure to BPs is an order of magnitude higher in North America than in Asia and Europe. Studies conducted on laboratory animals and cells have consistently demonstrated the toxic effects of BP exposure. BPs are estrogenic and elicit reproductive and developmental toxicities. Furthermore, neurotoxicity, hepatotoxicity, nephrotoxicity, and carcinogenicity have been reported from chronic BP exposure. In addition to animal and cell studies, epidemiological investigations have identified associations between BPs and couples' fecundity and other reproductive disorders, as well as adverse birth outcomes. Further studies are urgently needed to understand the risks posed by BPs on human health.

Allergic contact dermatitis to lip care cosmetic products - a systematic review

Aim: Lip care cosmetics products are any external preparation used by people to prevent drying, chapping, dullness, and beautification of lips. This study aimed to review the literature on allergic reactions induced by different types of lip care cosmetic products. Methods: A literature search was performed in PubMed from inception to June 2022. The study included articles published in English and available in full text. References of illegible articles were searched. Studies describing any patient who developed allergic contact dermatitis after the application of lip care cosmetic products were included. Results: A total of 47 reports consisting of 58 individuals experienced allergic reactions to lip care products. Several lip care cosmetics products, such as lipsticks, lip balms, lip salve, lip gloss, lip liner, and lip plumper, were found to be associated with allergic reactions. The most common ingredients that caused the allergic contact dermatitis were castor oil, benzophenone-3, gallate, wax, and colophony. Conclusions: Lip care cosmetics products contain several components that have been associated with allergic reactions. Awareness needs to be created among the general public and dermatologists regarding the presence of possible allergens in lip care cosmetic products.

Epidemics of Dermatitis

Allergic contact dermatitis (ACD) remains a globally prevalent disease for both children and adults. The silent ACD epidemic continues to be fueled by the introduction of novel allergens in industrial and household products and the continued presence of known allergens. In 1997, Allan Dillarstone noted a sinusoidal pattern to epidemics when allergenic preservatives were replaced by alternative chemicals within the market, which then similarly increased in allergenicity. A call for public health vigilance and prevention initiatives is needed to intervene in the ACD epidemic.

Visible light. Part II: Photoprotection against visible and ultraviolet light

Cutaneous photobiology studies have focused primarily on the ultraviolet portion of the solar spectrum. Visible light (VL), which comprises 50% of the electromagnetic radiation that reaches the Earth's surface and, as discussed in Part I of this CME, has cutaneous biologic effects, such as pigment darkening and erythema. Photoprotection against VL includes avoiding the sun, seeking shade, and using photoprotective clothing. The organic and inorganic ultraviolet filters used in sunscreens do not protect against VL, only tinted sunscreens do. In the United States, these filters are regulated by the Food and Drug Administration as an over-the-counter drug and are subject to more stringent regulations than in Europe, Asia, and Australia. There are no established guidelines regarding VL photoprotection. Alternative measures to confer VL photoprotection are being explored. These novel methods include topical, oral, and subcutaneous agents. Further development should focus on better protection in the ultraviolet A1 (340-400 nm) and VL ranges while enhancing the cosmesis of the final products.

Robust natural ultraviolet filters from marine ecosystems for the formulation of environmental friendlier bio-sunscreens

Ultraviolet radiation (UVR) has detrimental effects on human health. It induces oxidative stress, deregulates signaling mechanisms, and produces DNA mutations, factors that ultimately can lead to the development of skin cancer. Therefore, reducing exposure to UVR is of major importance. Among available measures to diminish exposure is the use of sunscreens. However, recent studies indicate that several of the currently used filters have adverse effects on marine ecosystems and human health. This situation leads to the search for new photoprotective compounds that, apart from offering protection, are environmentally friendly. The answer may lie in the same marine ecosystems since molecules such as mycosporine-like amino acids (MAAs) and scytonemin can serve as the defense system of some marine organisms against UVR. This review will discuss the harmful effects of UVR and the mechanisms that microalgae have developed to cope with it. Then it will focus on the biological distribution, characteristics, extraction, and purification methods of MAAs and scytonemin molecules to finally assess its potential as new filters for sunscreen formulation.

Relationship between acne and the use of cosmetics: Results of a questionnaire study in 539 Korean individuals

BACKGROUND

Acne vulgaris is one of the most common dermatological diseases, and it is known that various factors are related to triggering this condition in a patient. In particular, although the use of cosmetics is thought to be associated with the onset of a patient developing acne, there are few studies that have been conducted to date on this disease and its related factors.

METHODS

To begin with, a total of 539 patients with acne vulgaris, who visited three dermatologic clinics in Korea, were asked to complete a questionnaire regarding their condition in relation to clinical features and exacerbating factors, including the use of cosmetics. The patients all provided an accurate acne treatment history as well.

RESULTS

Among the respondents, 38.1% of patients who failed treatment answered that the condition of their acne was worsened by the continued use of cosmetics, which was significantly higher than 26.3% of the surveyed treatment-naive patients (P < .05). In this relation, double cleansing (cleansing twice using oil and water-based cleanser) and the number of cosmetics in use were also noted in higher numbers than in the treatment-failure patients. As noted, the liquid-type foundation and concealer were frequently used in this group.

CONCLUSIONS

This study showed the influence of cosmetics, especially in acne patients with a history of treatment failures. These results also show differences according to specific cosmetic types and formulations. Therefore, overall dermatologists should consider advising about cosmetic use to acne patients along with medical treatment options for the patients with acne.

Pediatric allergic contact dermatitis. Part 2: Patch testing series, procedure, and unique scenarios

Patch testing is the criterion standard for diagnosing allergic contact dermatitis. Causative allergens differ between children and adults, necessitating the development of pediatric-specific patch test series. The Pediatric Baseline Series was developed in 2018 through expert consensus and includes relevant pediatric allergens that dermatologists can use in practice. Obstacles in patch testing, such as the need for multiple office visits, length of patch application, and avoidance of sweat and water on the testing area, are particularly challenging for the pediatric population, and several strategies are proposed. Aside from formal patch testing, alternatives like the repeat open application test and empiric allergen avoidance can be helpful in children. The key to management of allergic contact dermatitis is allergen avoidance, with emphasis on the need to properly identify causative allergens. Continued data collection through registries allows for a better understanding of the diagnosis and management of pediatric allergic contact dermatitis.

Reinvestigating the Photoprotection Properties of a Mycosporine Amino Acid Motif

With the growing concern regarding commercially available ultraviolet (UV) filters damaging the environment, there is an urgent need to discover new UV filters. A family of molecules called mycosporines and mycosporine-like amino acids (referred to as MAAs collectively) are synthesized by cyanobacteria, fungi and algae and act as the natural UV filters for these organisms. Mycosporines are formed of a cyclohexenone core structure while mycosporine-like amino acids are formed of a cyclohexenimine core structure. To better understand the photoprotection properties of MAAs, we implement a bottom-up approach by first studying a simple analog of an MAA, 3-aminocyclohex-2-en-1-one (ACyO). Previous experimental studies on ACyO using transient electronic absorption spectroscopy (TEAS) suggest that upon photoexcitation, ACyO becomes trapped in the minimum of an S₁ state, which persists for extended time delays (>2.5 ns). However, these studies were unable to establish the extent of electronic ground state recovery of ACyO within 2.5 ns due to experimental constraints. In the present studies, we have implemented transient vibrational absorption spectroscopy (as well as complementary TEAS) with Fourier transform infrared spectroscopy and density functional theory to establish the extent of electronic ground state recovery of ACyO within this time window. We show that by 1.8 ns, there is >75% electronic ground state recovery of ACyO, with the remaining percentage likely persisting in the electronic excited state. Long-term irradiation studies on ACyO have shown that a small percentage degrades after 2 h of irradiation, plausibly due to some of the aforementioned trapped ACyO going on to form a photoproduct. Collectively, these studies imply that a base building block of MAAs already displays characteristics of an effective UV filter.

Unravelling the Photoprotective Mechanisms of Nature-Inspired Ultraviolet Filters Using Ultrafast Spectroscopy

There are several drawbacks with the current commercially available ultraviolet (UV) filters used in sunscreen formulations, namely deleterious human and ecotoxic effects. As a result of the drawbacks, a current research interest is in identifying and designing new UV filters. One approach that has been explored in recent years is to use nature as inspiration, which is the focus of this review. Both plants and microorganisms have adapted to synthesize their own photoprotective molecules to guard their DNA from potentially harmful UV radiation. The relaxation mechanism of a molecule after it has been photoexcited can be unravelled by several techniques, the ones of most interest for this review being ultrafast spectroscopy and computational methods. Within the literature, both techniques have been implemented on plant-, and microbial-inspired UV filters to better understand their photoprotective roles in nature. This review aims to explore these findings for both families of nature-inspired UV filters in the hope of guiding the future design of sunscreens.

Ultraviolet filters in sunscreen products labeled for use in children and for sensitive skin

BACKGROUND

The active ingredients in sunscreen products are ultraviolet (UV) filters, many of which are known potential allergens. The use of sunscreen in younger children and individuals with sensitive skin requires special attention, since absorption and allergen sensitization are of concern.

OBJECTIVE

This study aims to evaluate the ultraviolet filters in sunscreen products labeled specifically for "kids" or as "sensitive/hypoallergenic" and compare these to general sunscreen products.

METHODS

From December 2017 to March 2018, the ingredient labels on commercially available sunscreen products in Bangkok, Thailand, were analyzed.

RESULTS

Two hundred and forty-six sunscreen products were examined. Of these, twenty products (8.1%) were marketed for "kids." Forty-one products (16.6%) were labeled as "sensitive" or "hypoallergenic." Ethylhexyl methoxycinnamate (EHMC) and benzophenone-3 (BP3) were less prevalent in products for children [(P = .004) and (P = .029), respectively]. Eighty-five percent of sunscreen products labeled for kids contained at least one chemical UV filter. There was no significant difference between BP3, butyl methoxydibenzoylmethane (BMDM), and octocrylene (OCR) in products labeled for sensitive skin compared to products with no specific labels. Moreover, methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT) was more commonly found in products for sensitive skin than in nonsensitive products (P = .001).

CONCLUSIONS

Common allergenic UV filters were found in sunscreens labeled as sensitive and for children. Regulations for displaying these specific labels should be established for improved benefits and safety to allergy-prone skin.

[Effects of solar radiation and an update on photoprotection]

Sunburn, immunodepression, photoaging, and photocarcinogenesis, are some of the most significant adverse effects of solar radiation in humans. Children are population group of special vulnerability, due to the fact that exposure to the sun has more pronounced biological effects compared to adults. Furthermore, childhood is a critical period for promoting the development of photo damage and photocarcinogenesis in the later stages of life if adequate measures at not put into place. This is because it is estimated that between 18 and 20 years of age is when 40% to 50% of the accumulative exposure to ultraviolet radiation up to 60 years of age is received. The most important strategy for the photoprotection of children is changes in behaviour and habits associated with exposure to the sun at all levels (school, society, family, etc.). Resorting to the shade, reduction in overall time of exposure to the sun, and physical protection (clothes, hats, and sunglasses) are the best and least costly photoprotection strategies. The photoprotectors must be incorporated into the daily routine of children in the same way as adults, and must complete a series of requirements in order to make them effective, safe, and in line with the environment.

What's New in Photoprotection: A Review of New Concepts and Controversies

Cumulative ultraviolet exposure plays a critical role in photodamage. Recent advancements in photomedicine have resulted in a more thorough understanding of these mechanisms. Despite this, the adoption of routine sun protective practices is commonly not undertaken regularly by a large proportion of the public. Various obstacles exist that contribute to the public's nonadherence to these practices. Sunscreens, which are an integral component in all photoprotective regimens, have been questioned recently in terms of their safety. The aim of this article is to provide an overview of new concepts in photoprotection and also address current controversies pertaining to sunscreens.

Safety Assessment of Tocopherols and Tocotrienols as Used in Cosmetics

The Cosmetic Ingredient Review (CIR) Expert Panel (Panel) assessed the safety of 14 tocopherols and tocotrienols and concluded these ingredients are safe as used in cosmetics. The tocopherols are reported to function in cosmetics as antioxidants or skin-conditioning agents; in contrast, tocotrienols are not reported to function as an antioxidants in cosmetics but as a light stabilizer, oral care agent, or skin-conditioning agent. The Panel reviewed the new and existing animal and clinical data to determine the safety of these ingredients and found it appropriate to extrapolate the existing information to conclude on the safety of all the tocopherols and tocotrienols.

Dermatological and environmental toxicological impact of the sunscreen ingredient oxybenzone/benzophenone-3

Oxybenzone (Benzophenone-3) is an emerging human and environmental contaminant used in sunscreens and personal care products to help minimize the damaging effects of ultraviolet radiation. The Center for Disease Control fourth national report on human exposure to environmental chemicals demonstrated that approximately 97% of the people tested have oxybenzone present in their urine, and independent scientists have reported various concentrations in waterways and fish worldwide. Oxybenzone can also react with chlorine, producing hazardous by-products that can concentrate in swimming pools and wastewater treatment plants. Moreover, adverse reactions could very well be increased by the closed loop of ingesting fish contaminated with oxybenzone and/or washing the ingredient off our bodies and having it return in drinking water as treatment plants do not effectively remove the chemical as part of their processing protocols. In humans, oxybenzone has been reported to produce contact and photocontact allergy reactions, implemented as a possible endocrine disruptor and has been linked to Hirschsprung's disease. Environmentally, oxybenzone has been shown to produce a variety of toxic reactions in coral and fish ranging from reef bleaching to mortality. Lastly, with the rise in skin cancer rates and the availability of more effective sunscreen actives such as micronized zinc oxide and titanium dioxide, serious doubts about the relative prevention benefit of personal care products containing oxybenzone must be raised and compared with the potential negative health and environmental effects caused by the accumulation of this and other chemicals in the ecosystem.

Current challenges in photoprotection

Electromagnetic radiation in the ultraviolet, visible, and infrared ranges all produce biologic effects. Ultraviolet filters are the most well-studied photoprotective measure for the adverse effects of ultraviolet radiation. Because of the reported endocrinologic effects of oxybenzone in animal studies, its effects on coral reefs, and its photocontact allergy potential, its use has been minimized in many countries worldwide. New developments in topical antioxidants and oral and subcutaneous agents (eg, Polypodium leucotomos extract, afamelanotide, nicotinamide) with photoprotective and antiphotocarcinogenic properties could potentially provide addition modalities for protection against the effects of visible light and infrared radiation.

Photopatch testing in Bogota (Colombia): 2011-2013

BACKGROUND

Photopatch tests are used to diagnose photoallergic contact dermatitis and identify the causal agents. The frequencies of positive results and associated allergens vary by country; therefore, it is necessary to know the information specific to each country.

OBJECTIVE

To establish the frequency of positive photopatch test results, and their relevance, in patients with suspected photoallergic contact dermatitis in a national dermatology centre located in Bogota, Colombia.

MATERIALS AND METHODS

One hundred patients investigated for possible photoallergic contact dermatitis were enrolled in the study. They were photopatch tested with a selected group of allergens, and occluded for 48 hours; the duplicate right-hand panel was irradiated with 5 J/cm(2) ultraviolet (UV)A. The readings were performed on day (D)2, D4, and D6, in accordance with the guidelines of the ICDRG, and the relevance was evaluated with the COADEX system.

RESULTS

There were a total of 20 photopatch reactions in 15 patients, 95% of which were caused by UV filters, most frequently benzophenone-3 (55%). Eight of the positive reactions (53.3%) appeared on D6.

CONCLUSIONS

UV filters continue to be the most common causes of photoallergic contact dermatitis in our patients. Readings up to D6 (96 h after irradiation) are important to identify delayed positive reactions.