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Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Valid acute toxicity tests with the test substance are available for three freshwater species from three trophic levels. In all tests the EC/LC50 was higher than the water solubility of the substance (< 0.5 mg/L).

In the algae study no effects were observed in the tested undiluted filtrate with a loading rate of 100 mg/L (NOEC >= 0.011 mg/L). In the Daphnia study 5% immobilization was observed within the limits of water solubility (EC50 > water solubility). In all three fish tests no mortality was observed within water solubility. The key study (Scheerbaum, 1996) showed that even in an emulsion with 100 mg/L nominal, no effects were observed (LC50 > 82 mg/L measured conc.). A study using an emulsifier (Caspers, 1996) showed as well no mortality up to the water solubility limit (LC0 >= 0.22 mg/L; loading rate 2.5 mg/L). In a third study (Caspers, 1992) the toxicity was tested far above the water solubility of the substance (62 to 1000 mg/L). Up to 250 mg/L (nominal) no mortality was observed. The LC50 was determined to be 613 mg/L (nominal), where the mortality can be attributed to physical effects instead of systemic effects.

Furthermore a valid respiratory inhibition study with activated sludge is available: The substance did not inhibit the microbial activity in activated sludge up to a nominal concentration of 1000 mg/L. At 10000 mg/L 14.3% inhibition were observed. The EC50 is > 10000 mg/L and the substance is not considered to be toxic to sewage sludge bacteria.

Thus, no acute toxicity is expected for aquatic organisms within the water solubility of the test substance and above.

No long-term tests on aquatic toxicity are available, but as the substance has a very low water solubility and a high log Kow the substance is expected to bind primarily to sludge and sediments. Therein it is expected to be rapidly degraded as it was proved to be readily biodegradable.