Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Undecylenic acid is produced above 100 tons per year and has a log Kow superior to 3 (log Kow=4). Therefore, in the absence of any other information, a fish bioaccumulation study would normally be required by the annex IX of the 1907/2006 EC regulation. However, according to the annex XI of the EC 1907/2006 regulation, a weight of evidence approach can be used to assess if conducting a formal OECD 305 is required:

1) A computer simulation via EPI Suite TM (using an experimental log Kow of 4.0, coming from the Klimisch-1-rated study of GRL 2009, see section 4.7 “Partition coefficient”) gave a BCF for undecylenic acid of 3.16 L/kg wet-wt, which is far below the trigger value of BCF = 500 for classification with respect to chronic aquatic toxicity.

2) It is indicated in the toxicokinetic report that inside of an organism, undecylenic acid should be degradable within the available fatty acid metabolism system (see section 7.1 “Toxicokinetics, metabolism and distribution”).

3) Undecylenic acid is readily biodegradable, which reduces the exposure windows in the aquatic environment and allows ruling out both PBT and vPvB categorisation.

Based on this weight of evidence, we conclude that bioaccumulation of undecylenic acid is unlikely. Thus, the study on bioaccumulation of undecylenic acid can be waived, which is - in addition - in accordance to the intention of the REACH regulation to reduce animal use by conducting unnecessary testing on vertebrates.