Reaction mass of 1,1'-(2,2,4-trimethylhexane-1,6-diyl)bis-1H-pyrrole-2,5-dione and 1H-Pyrrole-2,5-dione, 1,1'-(2,4,4-trimethyl-1,6-hexanediyl)bis-

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

The PBT-assessment was performed in accordance with the ECHA Guidance R.11 (ECHA, 2017).

Persistence

The substance is not readily biodegradable. In a test following OECD guideline 301B a degradation rate of 8% was determined after an incubation period 28 days. Abiotic degradation by hydrolysis was observed in study following OECD 111. The hydrolysis rate strongly depends on the pH and temperature. A fast hydrolysis with a DT50 ≤2.4 h was determined at pH 9 at 20 and 30 °C, whereas moderate to slow hydrolysis was demonstrated at pH 4 and pH 7 and environmentally relevant temperatures. Based on the available data the substance is assessed as potentially P/vP.

Bioaccumulation

The experimentally determined Pow of the major component at neutral pH is 240 (log Pow 2.38). QSAR calculations performed for the substance components estimated log Pow values < 4.5. The available screening information indicates that the compound does not meet the B-criterion.

Toxicity

Chronic toxicity data are only availabe for algae (Pseudokirchneriella subcapitata). The EC10 (72 h) determined in a study following OECD 201 is 0.66 mg/L. Short-term toxicity studies are available for the standard trophic levels fish (Danio rerio), aquatic invertebrates (Daphnia magna), and algae (Pseudokirchneriella subcapitata). For fish, the most sensitive organism group, a LC50 (96 h) of 0.0602 mg/L was determined. The determined LC50 is < 0.1 mg/L and thus the substance needs to be considered as potentially T.

 

Impurity 1

For impurity 1 no data is available regarding persistence properties. According to two reliable in silico predictions this impurity has a log Pow of 3.33 (EpiSuite) and a logD of 1.62 (ACD labs and does therefore not fulfil the B criterion. For the impurity no data is available regarding toxicity properties. This leads to the conclusion that impurity 1 neither fulfils the criteria for persistent and bioaccumulative (PBT-substances), nor the criteria for very persistent and very bioaccumulative substances (vPvB-substances) according to REACH, Annex XIII and as laid down in the TGD R.11 of the European Chemicals Agency.

 

Impurity 2

For impurity 2 no data is available regarding persistence properties. According to two reliable in silico predictions this impurity has a log Pow of and does therefore not fulfil the B criterion. For the impurity no data is available regarding toxicity properties. This leads to the conclusion that impurity 2 neither fulfils the criteria for persistent and bioaccumulative (PBT-substances), nor the criteria for very persistent and very bioaccumulative substances (vPvB-substances) according to REACH, Annex XIII and as laid down in the TGD R.11 of the European Chemicals Agency.

 

Additive

The additive fulfils the criteria for toxic substances. The additive neither fulfils the criteria for persistent and bioaccumulative (PBT-substances), nor the criteria for very persistent and very bioaccumulative substances (vPvB-substances) according to REACH, Annex XIII and as laid down in the TGD R.11 of the European Chemicals Agency (ECHA).

 

In conclusion the substance is not PBT/vPvB.