Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

If released in water,12-ketochenodeoxycholic acid is expected to biodegrade quite quickly, according to results of the ready biodegradability test. Thus, the test item, although it is not used in a detergent, can be considered a surfactant as defined in Regulation 648/2004/EC: “any organic substance and/or mixture used in detergent, which has surface-active properties and which consist of one or more hydrophilic and one or more hydrophobic groups of such a nature and size that is capable of reducing the surface tension of water, and of forming spreading or adsorption monolayers at the water-air interface, and of forming emulsions and/or microemulsions and/or micelles, and of adsorption at water-solid interfaces”. Therefore, a surfactant shall be considered as biodegradable if the level of biodegradability is at least 60% within 28 days, irrespectively from 10-day window principle. In this test, carried out according to OECD TG 301F, the similar substance ursodeoxycholic acid reached 53.4% of degradation after the 10-d window, and 82% after 28 days. Therefore 12-ketochenodeoxycholic acid is considered readily biodegradable.

According to the results of the abiotic degradation hydrolysis test, it can be concluded that the hydrolysis of ursodeoxycholic acid is lower than 10% after 5 days at pH values 4, 7 and 9 and therefore, 12-ketochenodeoxycholic acid is not expected to hydrolyze.

If released in soil,12-ketochenodeoxycholic acid is expected to have a high mobility, according to the Koc value of 48 (logKoc: 1.69) obtained on the basis of a test performed on the similar substance ursodeoxycholic acid, according to OECD TG 121 (Estimation of the Adsorption / Desorption Coefficient Koc).

Distribution of 12-ketochenodeoxycholic acid into the atmosphere is not expected, based on the low vapour pressure (1.87 * 10-8mmHg at 20° C).