Insights and controversies on sunscreen safety

Area of Science:

• Photobiology
• Dermatology
• Toxicology
• Biotechnology

Background:

• Ultraviolet (UV) radiation from sunlight causes skin damage, including erythema, photoaging, and photocarcinogenesis.
• Endogenous cellular defense systems may be insufficient against chronic UV exposure, necessitating artificial protection like sunscreens.
• Concerns exist regarding the safety of UV filters, with reported issues including endocrine alterations, allergies, and oxidative stress.

Purpose of the Study:

• To address the limitations of current photobiological tests for sunscreen photosafety assessment.
• To highlight the need for robust and efficient in vitro screening methods for evaluating sunscreen safety.
• To introduce Saccharomyces cerevisiae as a promising model for comprehensive photosafety evaluation.

Main Methods:

• Review of existing photobiological tests for sunscreen photosafety.
• Analysis of limitations in current testing protocols, including reliability, phototoxic effect assessment, cell UV sensitivity, and irradiation parameters.
• Exploration of Saccharomyces cerevisiae as a model organism for in vitro photosafety screening.

Main Results:

• Current mandatory phototoxicity tests for sunscreens are insufficient, and photogenotoxicity testing is not standard.
• Existing photobiological tests have limitations affecting the reliability of photosafety assessments.
• Saccharomyces cerevisiae demonstrates potential as a model to enhance the robustness and scope of sunscreen photosafety testing.

Conclusions:

• There is a critical need for improved in vitro methods to ensure the safety of widely used sunscreens.
• Saccharomyces cerevisiae offers a viable model to overcome current testing limitations and improve photosafety assessment.
• Developing advanced screening tests is essential for a more comprehensive evaluation of sunscreen efficacy and safety.