A mixture of: isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-dodecylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-tetracosylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-5,6-didodecyl-phenol. n=5 or 6

Endpoint summary

Additional information

Hydrolysis:

In accordance with column 2 of REACH Annex VIII, a test on hydrolysis (required in section 9.2.2.1) does not need to be conducted as the substance is highly insoluble in water (< 3E-04 g/L). Furthermore, the substance does not contain any functional groups that are susceptible to hydrolysis.

 

Biodegradation:

According to the key study (CIBA, 1986) the ready biodegradability of the test item was assessed over a 28 day period by the modified Sturm test (OECD 301B). The results of this study indicates that the test item cannot be classified readily biodegradable under conditions of the test. These results were supported by a water-sediment study (OECD 308) where no significant degradation of the test item was observed and the substance was concluded to be persistent (P). QSAR calculations predicted 126 possible metabolites including the main structures of the substance.

Accorrding to the key study (BASF 2020) the biodegradation in sediment and water was assessed (OECD 308). As a result the test substance can not be considered as readily biodegradable. In this study 31 metabolites in quantities >= 0.1 % but well below 10% were observed, although the amount of 27 metabolites was far below any quantity that allows for a identification of the compound. However, four of them could be identified and were thus subsequently analysis for its PBT/vPvB properties (see chapter 5.2 for further details and chapter 2.3 for overall conclusion)

 

Bioaccumulation:

The bioaccumulation and depuration of the test item were studied with 14C-labeled test substance in rainbow trout maintained in a continous flow-through system in accordance with OECD guideline 305. Mean bioconcentration factors at steady-state were in the range 66 - 179. Accumulation of radioactive residues was in the order edible < whole-fish < non-edible tissues and well below 1000, therefore the test item is not considered to be bioaccumulative. Elimination of the test item during the depuration phase was relatively slow. Kinetic analysis indicated that approximately 90% of the radioactive residues were eliminated in 36 - 44 days. Additionally, QSAR calculations confirmed no bioaccumulation potential for the predicted and identified metabolites measured in the OECD 308 study (BCF corrected from 2.69 to 363 l/kg) .

 

Adsorption/Desorption:

Adsorption/Desoprtion of the test item on soil was determined in a study according to OECD Guideline 106. As a result of this study the following estimation of the adsorption-coefficient (log Koc) of the test substance could be made: log Koc is higher than 5.6.