Sorbitan C16-18 (even numbered) fatty acid esters, ethoxylated (1-6.5 moles ethoxylated)

Short-term toxicity to fish

Description of key information

LC50 (96 h, Danio rerio) > 100 mg/L (nominal, WAF)

Additional information

Since no studies investigating the short-term toxicity to fish of sorbitan C16-18 (even numbered) fatty acid esters, ethoxylated (1-6.5 moles ethoxylated) are available, in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5 read across was conducted to three key studies from the structurally related source substances sorbitan stearate – C18 (CAS 1338-41-6), sorbitan laurate – C12 (CAS 1338-39-2) and sorbitan monolaurate ethoxylated (CAS 9005-64-5).

The study investigating fish toxicity of the structurally related substance sorbitan stearate (CAS 1338-41-6) was used as a read across. The test was conducted as a limit test, according to the Circular on Test Methods of New Chemical Substances (Japan), in a semi-static system, using Oryzias latipes as test organism (MoE, 2005). The fish were exposed to the nominal test concentration of 1000 mg/L, prepared as water accommodated fractions (WAF). No mortalities were observed at the test concentration, during the 96 h test period, and the LL50 was determined to be >1000 mg/L. The nominal concentration was used to express biological toxicity results as the mean measured concentration of 13.7 mg/L (corresponding to 1000 mg/L nominal) is far above the solubility of the test substance and the values are therefore questionable.

A study on the toxicity of sorbitan laurate (CAS 1338-39-2) to fish was considered as an appropriate read across. The key study was performed as a limit test, with Danio rerio as the test organism according to OECD guideline 203 and GLP (Teigeler, 2012). The fish were exposed to the nominal test concentration of 100 mg/L, prepared as water accommodated fractions (WAF). No mortalities were observed at the test concentration, during the 96 h test period resulting in a LC50 of > 100 mg/L (nominal, WAF).

One study on fish toxicity available for the source substance sorbitan monolaurate, ethoxylated (CAS 9005-64-5) was performed as a limit test, according to OECD guideline 203 and GLP (Teigeler, 2012). The test organism Danio rerio was exposed to the nominal loading rate of 100 mg/L, prepared as water accommodated fractions (WAF). No mortalities were observed at the test concentration, during test period and a LC50 (96 h) of > 100 mg/L was reported.

Based on the results from the structurally related read-across substances (in accordance to Regulation (EC) No 1907/2006 Annex XI, 1.5), which are characterized by a similar ecotoxicological profile, it can be concluded that the sorbitan C16-18 (even numbered) fatty acid esters, ethoxylated (1-6.5 moles ethoxylated) will not exhibit acute effects to fish.