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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1996
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: performed in accordance with OECD and GLP guidelines

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report date:
1996

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes (incl. QA statement)
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
4'-ethoxy-3-hydroxy-2-naphthanilide
EC Number:
225-200-7
EC Name:
4'-ethoxy-3-hydroxy-2-naphthanilide
Cas Number:
4711-68-6
Molecular formula:
C19H17NO3
IUPAC Name:
N-(4-ethoxyphenyl)-3-hydroxy-2-naphthamide

Method

Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Metabolic activation system:
rat liver S9-mix
Test concentrations with justification for top dose:
1st + 2nd experiment: 4 - 5000 µg/plate
Vehicle / solvent:
Tested substance suspended in aqua bidest.
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: sodium azide (TA100, TA1535), 9-aminoacridine (TA1537), 2-nitrofluorene (TA98)
Remarks:
without metabolic activation
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene (all strains)
Remarks:
with metabolic activation
Details on test system and experimental conditions:
Method of application:
in agar (plate incorporation assay)
duration of incubation: approximatelyt 48h at 37°C in the dark

Determination of cytotoxicity:
Method:
1. experiment: reduction of spontaneous revertants or clearing of the bactarial background lawn
2. experiment: surving fraction (comparision of number of colonies between plates of solvent control and substance)
Evaluation criteria:
Increase of revertant colonies
Statistics:
Number of colonies per plate for each strain as well as mean values of the colonies of 3 plates/dose were counted.

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
Visible precipitation of the test compound was observed in the 1st and 2nd experiment at 100 µg/plate and above.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative without metabolic activation
negative with metabolic activation

The test substance was not mutagenic in the presence and absence of a metabolizing system in this tested Salmonella typhimurium reverse mutation assay.
Executive summary:

Naphtol AS-VL was tested for mutagenicity with the strains TA 100, TA1535, TA 1537, TA 98 of Salmonella typhimurium.

The mutagenicity studies were conducted in the absence and in the presence of a metabolizing system derived from rat liver homogenate. A dose range of 6 different doses from 4 to 5000 µg/plate (1st and 2nd exp.) was used.

Toxicity: The tested compound was proved to be not toxic to the bacterial strains with and without metabolic activation.

Mutagenicity: In the absence and in the presence of the metabolic activation system the test compound did not show a dose dependent increase in the number of revertants in any of the bacterial strains.

It can be stated that the tested sample of Naphtol AS-VL is not mutagenic in these bacterial test systems without and with exogenous metabolic activation at the dose levels investigated.