Undecan-4-olide

Endpoint summary

Description of key information

Acute and chronic data on the registered substance are available for three aquatic trophic levels: algae, aquatic invertebrates and fish and are summarised in the table below.

Aquatic trophic level	Level of exposure	Organisms	EC50 / LC50	EC10	Flag / reliability	Reference
Algae	Acute and Chronic	Pseudokirchneriella subcapitata	72h-ErC50 = 7.218 mg/L	72h-ErC10 = 1.669 mg/L	Key study / rel. 1	LPL, 2019
	Acute and Chronic	Pseudokirchneriella subcapitata	48h-ErC50 = 6.418 mg/L	48h-ErC10 = 0.990 mg/L	Disregarded study / rel. 3	HLS, 2012
Aquatic invertebrates	Acute	Daphnia magna	48h-EC50 = 5.85 mg/L	/	Key study / rel. 2	Bayer, 1999
	Chronic	Daphnia magna	/	21d-EC10 = 1.02 mg/L	Key study / rel. 2	NOACK, 2015
Fish	Acute	/	/	/	/	Waiving
	Chronic	Danio rerio, Pimephales promelas, Cyprinus carpio, Oncorhynchus mykiss	/	32d-EC10 = 0.84 mg/L	Key study / rel. 1	QSAR-KREATiS, 2019

 

Among all data available, the fish seems to be the most sensitive species in chronic exposure with a 32d-EC10 value at 0.84 mg/L. As a chronic data is available, the acute fish study does not need to be conducted.

To assess the toxicity of the registered substance to microorganisms a weight of evidence approach was used with four studies. The first and second studies were performed on the registered substance and no toxicity were observed. The third and fourth studies were performed on a similar substance, a linear saturated 4-hydroxycarboxylic acid derived-lactone with 10 carbons (one carbon less in the aliphatic chain than the registered/target substance). Both substances have similar mechanism of action (MechoA 2.1) and share a common basic structure. The source substance is considered adequate for read-across purpose (please refer to the RAAF document in IUCLID section 13 for detailed justification). The lowest EC50 value, determined at 800 mg/L, was chosen as key value for the chemical safety assessment of the registered substance.