Benzophenone-type UV filters in aquatic ecosystems: Sources, toxicological impacts, and interactions with coexisting stressors.
Benzophenone-type UV filters (BPs) are widely used in personal care products and various industrial applications, resulting in their continuous release into aquatic environments. BPs have attracted significant attention as emerging contaminants because of their widespread use, structural diversity, environmental persistence, various exposure pathways, and adverse toxicological effects in aquatic organisms. Previous studies have largely focused on environmental occurrence and individual toxicological effects of BPs, whereas evidence regarding their interactions with multiple environmental stressors remains fragmented. Available evidence indicates that environmental factors and co-occurring contaminants can modify the environmental fate, bioavailability, bioaccumulation, and toxicity of BPs, resulting in antagonistic, additive, or synergistic effects depending on the stressor, organism, and exposure conditions. Therefore, this review describes the widespread distribution and toxicological effects of BPs in aquatic ecosystems, examining how environmental factors and co-occurring contaminants modify the environmental fate and toxicological effects of BPs under multi-stressor conditions. This review suggests that the ecological significance of BPs lies not only in their intrinsic toxicity but also in the way multi-stressor interactions modify their biological impacts, thereby defining directions for future ecological risk assessment.