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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Valid acute toxicity tests with the test substance are available for three freshwater species from three trophic levels. The studies show that fish are the most sensitive species with a LC50 = 7.7 mg/L (based on geometric mean measured). In the guideline study over 96 hours under flow-through conditions 100% mortality was observed at the highest concentration that was possible to maintain in the system (11 mg/L). 15% mortality was observed at a concentration of 6.3 mg/L. The no-mortality concentration and the NOEC were 4.0 mg/L.

Two reliable daphnia studies are available. In both the EC50(48h) for the daphnia is above the highest concentration that could be maintained under test conditions (5.4 mg/L in the flow-through system). In the valid static algae study the ErC50 after 72 hours was greater than the highest concentration that could be maintained under test conditions (3.8 mg/L). An ErC10 of 0.65 mg/L was obtained.

The lowest L(E)C50 value of the three studies (Fish LC50 = 7.7 mg/L) is used in the hazard assessment and for derivation of aquatic PNECs.

The toxicity control in the 301F ready biodegradability test showed no inhibition of the microbial activity at a substance concentration of 100 mg/L. Therefore no further test on microbial toxicity was conducted and 100 mg/L was used as NOEC for the microorganism toxicity.

No long-term tests on aquatic toxicity are available, but as the risk assessment based on acute toxicity data demonstrated that there is no risk for the aquatic environment, there is no need to investigate further the effects on aquatic organisms.

Additional information