Toxicity of bisphenol A alternatives: A study on bisphenol E in two generations of the freshwater snail Lymnaea stagnalis

Bisphenol E (BPE), a substitute for bisphenol A (BPA), is becoming increasingly prevalent in the market and, consequently, the environment. Yet, the effects of such alternatives on aquatic organisms remain largely unknown. This study focuses on assessing the developmental toxicity of BPE in embryos (1.1 - 11,946 µg/L) from unexposed parents, as well as its reprotoxicity in adults (4.0 - 872 µg/L) of the Great Pond Snail Lymnaea stagnalis. We also examined the effects of BPE on F1 generation embryos (6.6 - 1037 µg/L) from exposed parents. Our study revealed developmental toxicity in embryos from unexposed parents from 5151 µg/L BPE, where the length, the heart rate, and hatching rate were lower than the control group. The embryo rotation was only lower at 11,946 µg/L. Malformations and delays in advancing through developmental stages were also observed. A reproduction test showed no changes in the number of laid egg masses, growth, and weight gain in snails exposed to up to 873 µg/L BPE. Only survival was affected at 187 and 873 µg/L BPE. Exposure of parents did not affect the development of embryos transferred to clean water but lowered the LOEC to 218 µg/L for F1 embryos kept exposed to BPE, compared to 5151 µg/L for exposed embryos from unexposed parents. BPE quantification using UHPLC-MS/MS revealed significant concentration variations, exceeding 20 % of the nominal concentrations, highlighting the importance of chemical analysis in chronic studies. The increased sensitivity of F1 embryos to BPE emphasizes the need for multigenerational approaches in refining ecotoxicological risk assessments of BPA alternatives.