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Hydrolysis:

The hydrolysis study of 1-phenylazo-2-naphthol was predicted using OECD QSAR toolbox version 3.3 (2017) to predict the hydrolysis half-life of test compound 1-phenylazo-2-naphthol (CAS No.842-07 -9). The half-life of 1-phenylazo-2-naphthol was estimated to be 108.89 days at temperature 25degC, indicating that the substance 1-phenylazo-2-naphthol is not hydrolysable.

Additional information

Hydrolysis:

In a different studies, 1-phenylazo-2-naphthol (CAS No. 842 -07 -9) has been investigated for its hydrolysis potential to a greater or lesser extent. These include predicted and experimental study for target substance 1-phenylazo-2-naphthol (CAS No. 842 -07 -9) and for its closest read across substance 1-[(2,5-dimethoxyphenyl)diazenyl]-2-naphthol (Citrus Red 2) (CAS No.- 6358-53-8) by considering its structure-activity relationships, were reviewed and are summarized as follows:

 

The hydrolysis study of 1-phenylazo-2-naphthol was predicted by SSS (2017) using OECD QSAR toolbox version 3.3 (2017) to predict the hydrolysis half-life of test compound 1-phenylazo-2-naphthol (CAS No.842-07 -9). The half-life of 1-phenylazo-2-naphthol was estimated to be 108.89 days at temperature 25degC, indicating that the substance 1-phenylazo-2-naphthol is not hydrolysable.

 

This is supported by the study from an authoritative database (Hazardous Substances Data Bank (HSDB);2017) for a read across substance 1-[(2,5- dimethoxy phenyl)diazenyl]-2-naphthol (Citrus Red 2) (CAS No.- 6358-53-8).The substance 1-[(2,5-dimethoxyphenyl)diazenyl]-2-naphthol (Citrus Red 2) (CAS No.- 6358- 53-8) is not expected to undergo hydrolysis in the environment due to the lack of functional groups that hydrolyze under environmental conditions.

  

Based on the above available studies for the target and read across substance, it can be concluded that the test substance 1-phenylazo-2-naphthol (CAS No. 842 -07 -9) is not expected to undergo hydrolysis in the environment i.e., it is not hydrolysable.