Unveiling the hidden toxicity of benzophenone-1 and benzophenone-8: Insights from Crepidula onyx, a marine invertebrate model

The increasing use of benzophenone-type UV filters, particularly benzophenone-1 (BP-1), benzophenone-3 (BP-3), and benzophenone-8 (BP-8), has raised concerns about their impact on marine ecosystems. While BP-3 is well-studied, BP-1 and BP-8 are emerging as potentially more hazardous compounds due to their prevalence and bioaccumulation potential. This study investigates the chronic and transgenerational effects of BP-1 and BP-8 on the marine invertebrate Crepidula onyx, focusing on development and reproduction. Newly hatched C. onyx larvae were exposed to environmentally realistic concentrations of BP-1 and BP-8 for 62 weeks, during which they developed through juvenile and adult stages. The study evaluated bioaccumulation and biotransformation through chemical analysis, alongside reproductive and developmental effects. Significant bioaccumulation of BP-1 and BP-8 was observed, particularly in females, with evidence of maternal transfer to embryos. Exposure to these compounds resulted in delayed male maturation, altered sex ratios, reduced reproductive success, and developmental abnormalities in F1 larvae. Notably, shell integrity was compromised, with reduced thickness and fracture force, suggesting disruption of biomineralization pathways. This research highlights the underestimated ecotoxicological effects of BP-1 and BP-8, emphasizing the need for expanded risk assessments of these UV filters. Future studies should focus on elucidating their mechanisms of action, potential for bioaccumulation, and long-term ecological consequences. These insights are crucial for developing strategies to mitigate the risks posed by these pervasive pollutants and protect marine biodiversity. © 2025 The Authors.