Registration Dossier

Ecotoxicological information

Endpoint summary

Administrative data

Description of key information

Additional information

Acute toxicity tests with isopentyl p-methoxycinnamate itself are available for three freshwater species from three trophic levels. For fish and microorganisms the results from the structural similar 2-ethylhexyl 4-methoxycinnamate were taken into account as well as the test with the test substance itself did not contain enough information to be assessed as reliable.

The studies show that freshwater algae are the most sensitive species for exposure to isopentyl p-methoxycinnamate. The GLP guideline study over 72 hours determined an ErC50 of 0.2 mg/L and a NOEC of 0.06 mg/L. The GLP guideline study with daphnia magna determined an EC50 of 0.28 mg/L – showing a toxicity in a similar range as the algae toxicity.

Acute toxicity tests with fish showed for isopentyl p-methoxycinnamate and 2-ethylhexyl 4-methoxycinnamate LC50s far above the water solubility (LC50 > 1000 mg/L).

The lowest L(E)C50 value of the three studies (Algae ErC50 = 0.2 mg/L) is used in the hazard assessment and for derivation of aquatic PNECs.

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 over a period of 3 hours resulting in a NOEC value of equal to or greater than 1000 mg/L.

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 further investigate the effects on aquatic organisms.