Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Acute toxicity studies have been conducted in fish, Daphnia and algae. In summary, for the aquatic compartment PnB shows LD50s/LC50s that exceed 500 mg/liter in fish (96 hr), in daphnia (48 hr) and algae (72 hr /96 hr).

Based on the molecular structure of PnB, no specific mechanism of action is expected to exert acute toxicity to the biota of the aquatic compartment. Accordingly, QSARs for neutral organics seem to adequately assess the effects of the substance, as can be concluded from a comparison of reported EC50 with EC50, estimated using ECOSAR software (ECOSAR module version 0.99 of the EPA EPIWIN family). PnB is expected to exert potential effects more rapidly as the uptake kinetic of similar molecules generally increases with the square of the surface of the molecule.

Based on the favourable acute aquatic toxicity data (no classification, PNEC = 0.5 mg/l), the readily biodegradability of the substances and the estimated PEC/PNEC ratios (clearly 1 for both wide-dispersive and non-dispersive use), no further testing is proposed for the aquatic environment.