Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Reading across results from EPIKOTE 828 (CAS No. 25068-38-6), the registered substance is considered to be susceptible to hydrolysis at pH 4, 7, and 10, with a hydrolysis half-life of 117 hrs at 25 °C (95% confidence range: 68–204 h). Products of hydrolysis are expected to be the mono-diol and the di-diol from ring-opening of the two epoxy groups.

 

Also, evidence of hydrolysis of the registered substance was observed during its water solubility test (Štreit, 2010).  A review of “Fig. No. 1:LC/MS analysis of Grilonit 1/10 water solution” in the Annexes reveal that the primary peak (Retention Time = 10.2 mins) fell from ~3.5 to ~2.2 over the course of the 4-day experiment (3 days at 30°C + 1 at 20°C). This amounts to a 37% loss of the primary component over this 96-hour [4 day] period, which is most probably due to ring-opening hydrolysis of the epoxy groups, and compares well with the 50% loss seen for the read-across substance in 117 hrs [~4.9] days at 25°C, further supporting the read-across.

 

The substance is not readily biodegradable, but appears to show evidence of slow aerobic degradation that did not plateau before the end of a 28-day study. An extended Modified OECD Screening test (OECD 301 F, EC C.4-D) demonstrated 98% degradation after 60 days, indicating a potential for complete mineralisation in the environment.

 

The substance is expected to have a low potential for aquatic / sediment bioaccumulation because it has a low octanol water partition coefficient.

 

The adsorption coefficient of the test substance on soil is estimated (OECD 121 and EU method C.19) as log Koc of 1.1 ± 0.7 (pH = 6.7, 25ºC) with a lower limit of 0.6 ± 0.8 and an upper limit of 3.0 ± 0.5 (pH 6.7, 25ºC). The adsorption coefficient of the test substance on sewage sludge is estimated as log Koc of 1.3 ± 0.9 (pH = 6.7, 25ºC) with a lower limit of 0.8 ± 1.0 and an upper limit of 3.3 ± 0.7.

 

In accordance with column 2 of REACh (Regulation (EC) No 1907/2006) Annex IX, the simulation testing on ultimate degradation in surface water, soil simulation testing, and sediment simulation testing (required in section 9.2.1.2, 9.2.1.3, and 9.2.1.4) do not need to be conducted based on the findings of the Chemical Safety Assessment; the substance does not fulfill classification criteria according to the applicable regulations and does not fulfill the criteria for vPvB or PBT. 

The substance is not expected to persist in the environment.