Registration Dossier

Diss Factsheets

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

NOEC (3 h): ≥ 1000 mg/L for the respiration of activated sludge microorganisms (OECD 209); read-across

Key value for chemical safety assessment

Additional information

No studies are available on the toxicity of Fatty acids, C6-18, 2,2-dimethyl-1,3-propanediyl esters (CAS No. 91031-27-5) to microorganisms. The assessment was, therefore, based on a study conducted with the structurally similar category member Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS No. 68855-18-5), as part of a read-across approach. This approach is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. Grouping of substance and read across. Further justification is given within the endpoint summary in IUCLID section 6.1 and within the category justification in IUCLID section 13.

The key study conducted with heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS No. 68855-18-5) was performed as a limit test according to the OECD Guideline 209 and GLP (Roulstone, 2012). Activated sludge of a predominantly domestic sewage was exposed to the nominal test concentrations of 10, 100 and 1000 mg/L during 3 hours. No inhibition of the respiration rate of the activated sludge was observed. In fact, the respiration rate was higher in all treatments, compared to the controls.

Additionally, 2,2-dimethyl-1,3-propanediyl dioleate is readily biodegradable (96% biodegradation in 28 days), which implies low toxicity to activated sludge microorganisms.

Thus, based on the above mentioned results, and due to the structural similarities and a consistent ecotoxicological/environmental fate profile of the substances, as are explained with in the overall endpoint summary in IUCLID section 6.1, it can be concluded that the toxicity of 2,2-dimethyl-1,3-propanediyl dioleate to aquatic microorganisms is very low. As it can be seen in the data matrix of the category justification in section 13 and the overall endpoint summary IUCLID 6.1, all reliable data in the polyol esters category support this hazard assessment by showing a consistent pattern of results.