Environmental fate of organic UV filters: Global occurrence, transformation, and mitigation via advanced oxidation processes

Abstract

Organic UV filters are used in personal care products, plastics, paints, and textiles to protect against UV radiation. Despite regulatory limits, these compounds still enter the environment through direct wash-off during swimming, evaporation, leaching from products, and incomplete removal in wastewater treatment plants. They have been detected in various environmental matrices worldwide. Once in the environment, organic UV filters can undergo phototransformation and biotransformation, forming transformation products that, together with parent substances, pose health risks to humans and wildlife and harm marine ecosystems, especially coral reefs. The increasing concern over water scarcity and the environmental impact of pollutants underscores the importance of eliminating these contaminants from aquatic environments. This review primarily focuses on organic UV filters approved for use in sunscreens, many of which are also utilized in other materials, with a few exceptions including UV stabilizer UV-328. It includes an in-depth analysis of 155 peer-reviewed articles published from 2015 to 2024, assessing the concentrations of these filters in various environmental matrices, including water and solid matrices, air and biota. Moreover, this review explores the environmental transformation of these chemicals and assesses the effectiveness of advanced oxidation processes (AOPs) in removing these pollutants. The findings highlight the pervasive presence of organic UV filters in the environment and the promising potential of AOPs to mitigate the associated environmental challenges.