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Link to relevant study record(s)

Reference
Endpoint:
basic toxicokinetics in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from EFSA journal and IARC monograph.
Reference:
Composition 0
Objective of study:
excretion
metabolism
Qualifier:
according to
Guideline:
other: as mentioned below
Principles of method if other than guideline:
Metabolism and excretion of the target substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol was studied in rats.
GLP compliance:
not specified
Test material information:
Composition 1
Radiolabelling:
not specified
Species:
rat
Strain:
not specified
Sex:
not specified
Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
no data
Duration and frequency of treatment / exposure:
no data
Remarks:
not specified
No. of animals per sex per dose:
no data
Control animals:
not specified
Positive control:
no data
Details on study design:
no data
Details on dosing and sampling:
no data
Statistics:
no data
Type:
metabolism
Results:
Th dye was easily reduced by intestinal bacteria to 1-amino-2naphthyl sulphate and eight 8 other metabolites, five of whch were red-coloured
Type:
excretion
Results:
excreted in urine
Metabolites identified:
yes
Details on metabolites:
1-amino-2naphthyl sulphate and 8 other metabolites (name not specified)
Conclusions:
The dye 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is said to be easily reduced by intestinal bacteria, after gavage administration to rats in corn oil 1-amino-2naphthyl sulphate and 8 other metabolites were excreted in urine.
Executive summary:

The dye 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is said to be easily reduced by intestinal bacteria, after gavage administration to rats in corn oil 1-amino-2naphthyl sulphate and 8 other metabolites were excreted in urine.

Description of key information

Basic toxicokinetics:

The dye 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is said to be easily reduced by intestinal bacteria, after gavage administration to rats in corn oil 1-amino-2naphthyl sulphate and 8 other metabolites were excreted in urine.

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential

Additional information

Basic toxicokinetics:

Two studies of the target substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol were reviewed for basic toxicokinetics endpoint, as cited in The EFSA Journal (2005) 263, 1-71, and are presented below as weight of evidence approach:

In key study, the dye 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is said to be easily reduced by intestinal bacteria, after gavage administration to rats in corn oil 1-amino-2naphthyl sulphate and 8 other metabolites were excreted in urine.

Other study indicates that after 14C-labelled Sudan II (1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol) was administered, 86% of the activity was found in the faeces with only 14% in the urine and 11 metabolites were identified, but these are not specified in the review.

Based on the above studies and by applyiing weight of evidence approach it can be concluded that majority of the test substance 1-[(2,4-dimethylphenyl)diazenyl]-2-naphthol is easily metabolised and excreted in urine and faeces, so the substance shows no bioaccumulation potential inside the body.