UV Filters: Challenges and Prospects

Abstract

The use of sunscreens is an established and recommended practice to protect skin from solar-induced damage. Around 30 UV filters can be used in sunscreen products in the European Union, which ought to follow the requirements of the regulation 1223/2009 to ensure their efficacy and safety for humans. Nevertheless, low photostability and putative toxicity for humans and environment have been reported for some UV filters. Particularly, the negative impact in marine organisms has recently raised concern on the scientific community. Therefore, it is important to develop new UV filters with improved safety profile and photostability. Over the last two decades, nearly 200 new compounds have revealed promising photoprotection properties. The explored compounds were obtained through different approaches, including exploration of natural sources, synthetic pathways, and nanotechnology. Almost 50 natural products and around 140 synthetic derivatives, such as benzimidazoles, benzotriazoles, hydroxycinnamic acids, xanthones, triazines, among others, have been studied aiming the discovery of novel, effective, and safer future photoprotective agents. Herein, we provide the reader with an overview about UV filters’ challenges and prospects, offering a forward-looking to the next-generation of UV filters.

Photoprotective Activity of Plants Used for Skin Disorders by the Native Population from the Brazilian Amazon Basin: A Preliminary Study

“…Compounds such as polyphenols (flavonoids, tannins), carotenoids, anthocyanins, fixed and volatile oils from vegetables, fruits and, plants parts are incorporated with success into sunscreens formulations because of their antioxidant property. [1,3,30,31] In the study, the concentrations of flavonoids and total phenols were high in the ethanolic extracts of C. icaco and K. pinnata, but A. triplinervis showed low levels of total phenols and no mensurable concentrations of flavonoids were found in the ethanolic extract.…”

“…[28] Incorporation of natural resources into sunscreens is in line with the concept of environmental sustainability as it can provide cosmetics with adequate cost-effectiveness to consumers, which allows for the popularization of these compounds, contributing to a decrease in the rate of skin cancer. [1,3,29,30] The antioxidant activity is an important property of sunscreens because the UVA radiation contributes to the production of reactive oxygen species in the layers of the skin, including the dermis promoting the oxidation of lipids and proteins, accompanied by depletion of enzymes and molecules responsible for antioxidant defenses. The anti-inflammatory response also is affected.…”

Probing photoprotection properties of lipophilic chain conjugated thiourea-aryl group molecules to attenuate ultraviolet-A induced cellular and DNA damages

“…The first and foremost step in the development of a new UV filter is to determine its toxic effect on both in vitro and in vivo model systems before moving toward the human trial 45 . Measuring the cytotoxic effect of compounds by using MTT dye is considered a gold standard 46 .…”

Sunscreen cosmetics as basic protection against photoaging

“…They also activate the improvement of the body's mineral homeostasis (especially phosphorus and calcium), increase the level of hemoglobin, and the number of erythrocytes, and contribute to lowering blood pressure. Under the influence of sunlight, the level of metabolism also increases [5,16].…”