Fatty acids, soya, conjugated

Short-term toxicity to aquatic invertebrates

Description of key information

No short-term toxicity effects up to the limit of water solubility

Additional information

No study is available on short-term toxicity of fatty acids, soybean oil, conjugated (CAS 1176286 -43 -3) with invertebrates.

Therefore ecotoxicological effects are predicted from adequate and reliable data for source substance(s) by read-across to the target substance within the group applying the group concept in accordance with Annex XI, Item 1.5, of Regulation (EC) No 1907/2006.

As the main constituents of the mixture are C16, C18', C18'' conjugated and C18'', read-across is performed to the saturated palmitic acid C16 (CAS 57 -10 -3) and the unsaturated oleic acid C18' (CAS 112 -80 -1). Only for these two components of the blend data on short-term toxicity to invertebrates are available. Furthermore, a supporting read across is performed to fatty acids, tall oil (CAS 61790 -12 -3), since the main components of this fatty acid mixture are also unsaturated C18 components (50 -60% C18', 35 -40% C18'') and

to a mixture with linoleic acid C18'' (CAS 60 -33 -3) with the following constituents: 60% C18'', 25% C18' and minor amounts of C18''', C16, C14 and C18.

Palmitic acid C16 was tested on daphnids in a 48 h static test (Ministry of the Environment, Government of Japan, 2000) according to OECD 202 under GLP conditions. In the limit test a nominal test concentration of 10 mg/L (corresponding to a measured concentration (geom. mean) of 4.8 mg/L) was applied by using a solvent. No effects on mobility of Daphnia magna could be observed during the test period of 48 h. Thus the EC50 is reported to be above 4.8 mg/L (measured concentration) which is far above the limit of water solubililty.

In the limit-test available conducted with oleic acid C18' Daphnia magna were exposed under semi-static conditions according to OECD 202 and in accordance with GLP requirements (Ministry of the Environment, Government of Japan, 2003). The EC50 (48 h) of this test was reported to be > 2.8 mg/L based on arithmetic mean measured concentrations (corresponding to > 3.6 mg/L based on nominal concentrations = limit of water solubility), no solvent was used in this test.

A further study on acute toxicity to daphnids with fatty acids, tall oil was conducted according to OECD 202 under GLP conditions (Pine Chemical Association, 2004). Daphnia magna was exposed to water accomodated fractions (WAF) of 1, 10, 100 and 1000 mg/L (nominal). Since no mortality was observed up to the highest loading rate a EL50(48h) of > 1000 mg/L was stated. Thus no effect up to the limit of water solubility could be detected.

Finally a GLP guideline study on a mixture with linoleic acid (content 60%) was conducted by Özkabakcioglu (2000) with Daphnia magna acccording to OECD 202. Daphnids were exposed for 48 h in a static test to WAFs of the test item, since the test substance has a low water solubility (< 2.2 mg/L in the test medium). Results were based on nominal loading rates, no effects were observed up to a loading rate of 30 mg/L. In the highest loading rate of 100 mg/L 100% mortality was observed, probably due to physical effects caused by this loading rate really far above the water solubility.

With regard to the listed results the conclusion can be drawn that short-term effects on invertebrates of fatty acids, soybean oil, conjugated are not expected up to the limit of water solubility.