N,N'-di-sec-butyl-p-phenylenediamine

Endpoint summary

Description of key information

The biodegradability of 44PD was estimated based on three different QSAR studies and two studies with a structural analog 77PD

Additional information

The biodegradability of 44PD was estimated based on three different QSAR studies and two studies with a structural analog 77PD. The difference between the two compounds is the somewhat larger alkyl group for 77PD (1,4 -dimethylpentyl amine) in comparison with 44PD (1 -methylpropyl amine).

77PD: C-C(-C)-C-C-C(-C)-N-Phenyl-N-C(-C)-C-C-C(-C)-C

44PD: C-C-C(-C)-N-Phenyl-N-C(-C)-C-C-C

Test results indicated that some biodegradation occurs. Based on structural similarity it can therefore be expected that this will also be the case for 44PD.

With regard to the QSARs carried out with 44PD, these were all well documented in the scientific literature and applicable for 44PD as this compound falls well within the domain of the QSARs and the structure of 44PD is similar to some of the compounds in the training and evaluation dataset of the QSARs. Allthough biodegradation rate estimates based on QSARs and structural analogs must be carried out with great care, the results of the QSAR studies and the read across studies are in good agreement, therefore the results are considered reliable. The results of the QSAR studies and the read across studies are similar: 44PD is not readily biodegradable.

On the other hand, experimental test results on 77PD reveal that some degree of biodegradation occurs. Based on structural similarity it can therefore be expected that this will also be the case for 44PD. In addition, 44PD is known to hydrolyze rapidly, with the formation of hydroquinone and 1 -methyl propylamine, which are known to be readily biodegradable and degradable, respectively. It is for these reasons that the biodegradation potential of 44PD in water was described as inherently biodegradable, not fulfilling specific criteria.