Fatty acids, C8-10, mixed esters with neopentyl glycol and trimethylolpropane

Short-term toxicity to fish

Description of key information

No effects up to the limit of water solubility.

Additional information

Since no studies investigating the short-term toxicity of Fatty acids, C8-10 (even numbered), diesters with neopentyl glycol and di- and triesters with trimethylolpropane (CAS 97281-24-8) to fish are available, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 a read-across to the structurally related source substances Fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6), Fatty acids, C8-10, triesters with trimethylolpropane (CAS 91050-89-4) and Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5) was conducted. The source substances are representative to evaluate the short-term toxicity of the target substance to fish. This read-across is justified in detail in the overall summary (IUCLID Section 6.1) and within the analogue justification in IUCLID Section 13. In this case of read-across, the best suited (highest degree of structural similarity, nearest physico-chemical properties) read-across substance was used for the assessment.

The first study with the source substance Fatty acids, C8-10 (even numbered), di-and triesters with propylidynetrimethanol (CAS 11138-60-6) was conducted according to OECD 203 (GLP) using the freshwater species Brachydanio rerio. Water accommodated fractions up to a limit loading rate of 10000 mg/L were tested under semi-static conditions. After 96 h no mortality was recorded resulting in a LL50 (96 h) > 10000 mg/L.

The second study with the source substance Fatty acids, C8-10, triesters with trimethylolpropane (CAS 91050-89-4) was conducted according to ISO 7346-1. The study was conducted with Danio rerio in a semi-static test system. Test organisms were exposed to two concentrations of 3000 and 10000 mg/L for 96 h. At test termination a LC50 (96 h) of >10000 mg/L based on nominal test substance concentrations was determined.

The third study with the source substance Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS 68855-18-5) was conducted according to OECD Guideline 203 and GLP, in a semi-static system, using Oncorhynchus mykiss as test organism. During 96 h, the fish were exposed to the nominal test concentrations of 100% v/v, corresponding to a measured concentration of 0.086 mg/L. This was the highest attainable concentration, due to the poor solubility of the test substance. The test solutions were prepared using a solvent, and undissolved test material was removed by filtration. No mortality occurred during the study, and the LC50 (96 h) was reported to be > 0.086 mg/L.

All of the results are supported with a study performed with the target substance itself. This study was rated “not reliable (RL3)” since the exposure duration is not in line with today’s standard methods (48 h instead of 96 h). However, it was shown that no effects occurred up to a nominal concentration of 1000 mg/L. The concentrations 3000 and 10000 mg/L cause 100% mortality. However, these effects are likely to be caused by physical effects rather than intrinsic effects of the solubilized part of the substance. This supports the results from the source substances that the target substance did not cause any mortality to fish.

Based on the available results from structurally related source substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5) which are characterized by a similar ecotoxicological profile and comparable structure and the supporting result for the target substance itself, it can be concluded that Fatty acids, C8-10 (even numbered), diesters with neopentyl glycol and di- and triesters with trimethylolpropane will not exhibit short-term effects on fish up to the limit of water solubility.