Reaction products of alkenyl dihydrofuran-2,5-dione and polyisoalkenyl dihydro-2,5-furandione with alkylene glycol

Endpoint summary

Description of key information

Abiotic degradation

The test item is a complex mixture for which the test guidelines for hydrolysis are not recommended. This is not only because components could have differenct hydrolytic rates but also hydrolysis products can be analytically indistinguishable from the starting components.

The test item as a whole was expected to be essentially insoluble in water (water solubility reported as < 0.13 mg/L). Therefore, the test solution concentration required that would dissolve all the components would be impractically low in order to perform the test and a sufficiently sensitive analytical method was not available. Overall, these issues would make hydrolysis testing unfeasible.

The main functional groups in the components of the test item which have the potential to hydrolyze are esters. Although esters usually hydrolyze readily, especially in alkaline conditions, some components of the test item may have a reduced hydrolytic potential due to them being essentially insoluble in water.

Biotic degradation

No study is available for the substance itself, however a study is available for the read-across substance, Ethylene glycol, reaction products with polyisobutenyl succinic anhydride and hexadecenyl succinic anhydride, salts with dimethylethanolamine.

A study was performed to assess the ready biodegradability of the this material in an aerobic aqueous medium. The method followed that described in OECD TG 301C "Ready Biodegradability; MITI Test" referenced as Method C.4 -F of Commission Directive 92/69/EEC. The test material was prepared as an aqueous dispersion at a final concentration of 100 mg/L, inoculated with micro-organisms from a laboratory culture originating from 10 different sites throughout the UK and incubated in the dark at 25 +/-0.1 deg C for 28 days. The degradation of the test material was assessed by the measurements of oxygen consumption, DOC analyses on days 0 and 28 and compound specific analyses on days 0 and 28. Control solutions with inoculum and the standard material, aniline, were used for validation purposes.

The test material attained a mean of 38% degradation calculated from oxygen consumption values after 28 days. The mean degradation rate from the DOC analyses was 42%. The mean degradation rate from the residual test material analyses was 100 %. The test material cannot be considered to be ready biodegradable under the strict terms and conditions of OECD TG 301C as the degradation rate calculated from the oxygen consumption values was < 60%.