2-Butenedioic acid (2E)-, di-C14-16-alkyl esters

Short-term toxicity to aquatic invertebrates

Description of key information

No toxic effects up to the limit of water solubility (< 0.15 mg/L in aqua dest) for Daphnia magna, read across

Additional information

Since no study for assessing the acute toxicity to aquatic invertebrates of 2-Butenedioic acid (2E)-, di-C14-16-alkyl esters (List No 695-949-6) is available, in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 Grouping of substances, a read-across to the structurally related category members 2-Butenedioic acid (E)-, didodecyl ester (CAS 2402-58-6, MW 453 g/mol), 2-Butenedioic acid (E)-, ditetradecyl ester (CAS 10341-03-4, MW 509 g/mol) and 2-Butenedioic acid (E)-, di-C18-22-alkyl esters (CAS 68921-53-9, MW 621-733 g/mol) was conducted. 2-Butenedioic acid (2E)-, di-C14-16-alkyl esters (List No 695-949-6) exhibits a molecular weight range of 508.82 – 564.92 g/mol. Thus, the read across is covered by interpolation for this substance. The read across is justified due to a) the structural similarity of the category members and b) similar physico-chemical properties resulting in a similar environmental fate and ecotoxicity profile.

Further justification is given in the endpoint summary 6.1 and within the category justification in section 13.

The study with 2-Butenedioic acid (E)-, didodecyl ester (CAS 2402-58-6) was conducted according to EU method C.2 and GLP (Küch, 1995).The test concentrations were measured using DOC analysis; however, the analysis showed that the test substance is only poorly soluble in water and thus the measurement could not be used as basis for the determination of an effect concentration. Two tests were conducted. One test applied test concentrations of 16, 64 and 80 mg/L test prepared using a vehicle and the other test applied a 100 mg/L test solution prepared without using a vehicle. The observed undissolved test material was not removed from the treatments in test 1, but the test solution is filtered in test 2. 48 h-EC50 values of 96 mg/L (test 1) and > 100 mg/L (test 2) are determined for Daphnia magna on the basis of the nominal concentrations. As no toxicity was observed using the filtered test solution the observed adverse effects in test 1 is expected to be related to physical interferences rather than systematic toxicity.

A study with 2-Butenedioic acid (E)-, ditetradecyl ester (CAS 10341-03-4) was conducted according to OECD 202 and GLP (Weber, 2012). No analytical determinations were performed since the solubility of the test item is below the limit of quantification (0.04 mg/L in this test). No effects on mobility were observed in the control and at 100 mg/L in this limit test. Thus the 48 h-EC50 is assessed as > 100 mg/L.

The study with 2-Butenedioic acid (E)-, di-C18-22-alkyl esters (CAS 68921-53-9) was performed under static conditions according to GLP and EU method C.2 using Daphnia magna as test organism (Küch, 1995).A nominal test concentration of 100 mg/L was applied in a limit test. No immobilization was observed in any treatment and the control during the test period of 48 hours. Accordingly, the 48h-EC50 is determined to be > 100 mg/L based on the nominal test concentration.

The results of all three studies show distinctly, that no effects occur in the range of water solubility and well above the water solubility.

Due to the structural and physico-chemical property similarities with the tested category members 2-Butenedioic acid (E)-, didodecyl ester (CAS 2402-58-6), 2-Butenedioic acid (E)-, ditetradecyl ester (CAS 10341-03-4) and 2-Butenedioic acid (E)-, di-C18-22-alkyl esters (CAS 68921-53-9), this result is also applicable to read across to 2-Butenedioic acid (2E)-, di-C14-16-alkyl esters (List No 695-949-6).