Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate (CAS No. 28510-23-8) is not readily biodegradable

Additional information

2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate (CAS No. 28510-23-8) is not readily biodegradable according to OECD criteria. Based on one GLP study according to OECD 301B a degradation of ≥ 20% after 28 days can be assumed (Desmares-Koopmans, 2010).Therefore, 2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate (CAS No. 28510-23-8) can be regarded as inherently biodegradable, not fulfilling specific criteria (ECHA, 2012b).

Another GLP study according to OECD 301B was prolonged up to 85 days (Desmares-Koopmans, 2012). In this study the pass level (60% CO2 evolution) was reached between days 62 to 69. In both tests (Desmares-Koopmans, 2010; 2012), a prolonged lag phase of 14 days or longer was shown before degradation of the test substance started. The toxicity controls showed that no inhibition of aquatic microorganisms occurred. Based on these two tests, it can be assumed, that microorganisms need to adapt their enzymes in order to degrade 2,2-dimethylpropane-1,3-diyl 2-ethylhexanoate (CAS No. 28510-23-8). Nevertheless once these are adjusted, good overall degradation rates can be achieved (overall degradability after 85 days = 74%). Therefore in accordance with Regulation (EC) No. 1907/2006, the substance is regarded as not persistent (not P).

Due to the high overall degradation rates as observed in the enhanced biodegradation test (Desmares-Koopmans, 2012) ultimate and complete degradation can be assumed for this substance. Consequently, further simulation testing for water and sediment or soil biodegradation tests are not necessary.

A detailed reference list is provided in the technical dossier (see IUCLID, section 13) and within the CSR.