4,4'-isopropylidenediphenol

Toxicity to other aquatic organisms

Description of key information

There is one key study for Bisphenol A which was evaluated to be Klimisch 1, reliable without restriction (Pickford et al., 2000; published as Pickford et al., 2003). In this non-guideline study which lasted 90 days, the NOEC for Xenopus laevis based on larval survival, adult growth and sex ratio was determined to be 497 µg/L, the highest dose of Bisphenol A tested. While there was no effect on any of the endpoints it shall specifically be mentioned that there was no impact on the frog sex ratio at all treatments or control, while in the positive control group there was a significant feminisation observed. Thus, the NOEC for all endpoints was determined to be > 497 µg/L.

Additional information

African clawed frog (Xenopus laevis) larvae at a developmental stage between 43 and 45, were exposed to nominal Bisphenol A concentrations of 0, 1.0, 2.3, 10, 23, 100, and 500 µg/L, in flow-through conditions until they reached complete metamorphosis (Pickford et al., 2000; published as Pickford et al., 2003). Results are reported based on nominal concentrations. After 90 days, larvae were sacrificed, and total length, snout-vent length and wet weight were measured. Sexual differentiation in larvae at developmental stages 58-66 was evaluated by inspection of gross gonadal morphology. The NOEC for survival, sex ratio, length and weight was determined to be 500 µg/L. There was no significant difference in mean percentage survival between Bisphenol A, positive control (17ß-estradiol), and dilution water control but there was a significantly lower survival rate at 500 µg/L than at 100 µg/L of Bisphenol A. Compared to the dilution control, there was no significant difference between growth, development, and time to metamorphosis in the Bisphenol A treatment groups while there was a significant difference in the positive control with regards to mean time to metamorphosis. There was also a significant increase in total length, snout-length, and wet weight in males between positive control and the dilution control but no noticeable difference in Bisphenol A froglets. Thus, the NOEC for all endpoints was determined to be ≥ 500 mg/L.

There is one study by Hutler-Wolkowicz et al., 2014 on Rhinella arenarum, which reported an acute 168-h LC50 of 7.1 mg/L, and which was rated reliability 2. It did not follow a validated guideline but is exploratory and received no adequate, complete documentation. Based on the data reported the study seems to be plausible and the most important basic data was provided. However, due to the indicated short-comings the study may only be used as supportive information but not as key study.

A further study with Xenopus laevis was identified (Levy et al., 2004). This study was disregarded due to major short-comings (Klimisch 3, not reliable) such as insufficient replication and erroneous statistical evaluation. Details on the short-comings are provided in the executive robust study summary.