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Bioaccumulation: aquatic/sediment

Using Bio-concentration Factor (v12.1.0.50374) module (Advanced Chemistry Development)/I-Lab predictive module, 2017), the BCF value of the test substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS no. 3118 -97 -6) at pH range 0-8 was estimated to be 4878 and at pH 9, 10, 11, 12, 13 and 14 was estimated to be 4877, 4876, 4863, 4734, 3746 and 1215, respectively (Log BCF ranges from 3.1 ± 1.0 to 3.7 ± 1.0). This value indicates that the test substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol was considered to be accumulative in aquatic organisms.

Additional information

Bioaccumulation: aquatic/sediment

Various predicted data for the target compound1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol(CAS No. 3118-97-6) and the supporting weight of evidence studies for its read across substance were reviewed for the bioaccumulation end point which are summarized as below:

 

In a prediction done by using Bio-concentration Factor (v12.1.0.50374) module (Advanced Chemistry Development)/I-Lab predictive module, 2017), the BCF value of the test substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS no. 3118 -97 -6) at pH range 0-8 was estimated to be 4878 and at pH 9, 10, 11, 12, 13 and 14 was estimated to be 4877, 4876, 4863, 4734, 3746 and 1215, respectively (Log BCF ranges from 3.1 ± 1.0 to 3.7 ± 1.0).

 

The bioaccumulation study from authoritative database (SRC PhysProp database, 2017) was conducted for estimating the BCF (bioaccumulation factor) value of test chemical 1- (2, 4-dimethylphenylazo)-2-naphthol (CAS no. 3118-97-6). The BCF (bioaccumulation factor) value of 1- (2, 4-dimethylphenylazo)-2-naphthol was determined to be 11748.97 dimensionless (log BCF = 4.07).

 

Bioaccumulation test was conducted for estimating the bioconcentration factor (BCF) of test chemical 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS no. 3118 -97 -6)(ChemSpider, 2017). The estimated bioconcentration factor (BCF) of 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol was estimated to be 7107.84 at pH 5.5 and 7.4, respectively.

 

Another predicted data was estimated usingSciFinder database (American Chemical Society (ACS), 2017) was used for predicting the bioconcentration factor (BCF) of test chemical 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol (CAS No. 3118 -97 -6). The estimated bioconcentration factor (BCF) of 1-[(2,4-dimethyl phenyl)diazenyl]-2-naphthol was estimated to be 8480 at pH range 1-9 and 8470 at pH 10 (at 25 deg C), respectively.

 

For the read across chemical 1-[(2-methoxyphenyl)diazenyl]-2-naphthol (CAS no. 1229-55-6) from authoritative database (HSDB, 2017),bioaccumulation study was conducted for estimating the BCF (bioaccumulation factor) value of read across chemical 1-[(2-methoxyphenyl)diazenyl]-2-naphthol. The bioaccumulation factor (BCF) value was calculated using an estimated log Kow of 7.5 and a regression derived equation. The BCF (bioaccumulation factor) value of 1-[(2-methoxyphenyl)diazenyl]-2-naphthol was determined to be 290000 dimensionless.

 

On the basis of above results for target chemical1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol(from ACD labs,SRC PhysProp database, ChemSpider and SciFinder database,2017) and for its read across substance from HSDB, it can be concluded that the BCF value of test substance1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol ranges from 1215 –11748.97which exceeds the bioconcentration threshold of 2000, indicating that the chemical 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is expected to bioaccumulate in the food chain.