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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / micronucleus study
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Limited report, non-GLP, the omission of information on status of cell division does not lower the reliability

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1999

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
other: OECD 487
Deviations:
yes
Remarks:
no method included to check cell division status
Principles of method if other than guideline:
Mouse lymphoma L5178Y cells were used in this study. Three types of treatment were carried out parallel: two treatments without metabolic activation with or without a recovery period after 24 h continuous treatment and one treatment with metabolic activation by S9 mix. The concentrations of the test substance were 1000, 500, 250 μg/mL in the three type of treatment. Mitomycin C was used as a positive control in the absence of S9 mix and cyclophosphamide was used as a positive control in the presence of S9 mix.
GLP compliance:
not specified
Type of assay:
in vitro mammalian cell micronucleus test

Test material

Constituent 1
Chemical structure
Reference substance name:
Benzoic acid
EC Number:
200-618-2
EC Name:
Benzoic acid
Cas Number:
65-85-0
Molecular formula:
C7H6O2
IUPAC Name:
benzoic acid
Details on test material:
Batch No.: not specifiedPurity: > 99%

Method

Target gene:
None stated
Species / strain
Species / strain / cell type:
mouse lymphoma L5178Y cells
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
1000, 500, 250 μg/mL (cytotoxicity at 200 ug/mL)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO- Justification for choice of solvent/vehicle:
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
no
True negative controls:
no
Positive controls:
yes
Positive control substance:
mitomycin C
Remarks:
In the absence of S9 mix
Untreated negative controls:
yes
Negative solvent / vehicle controls:
no
True negative controls:
no
Positive controls:
yes
Positive control substance:
cyclophosphamide
Remarks:
In the presence of S9 mix
Details on test system and experimental conditions:
METHOD OF APPLICATION: in mediumDURATION- Preincubation period: 10-12 h- Exposure duration: 24 h without S9 mix, 4 h with S9 mix- Expression time (cells in growth medium): 0 or 20 hours without S9 mix, 24 hours with S9 mix- Selection time (if incubation with a selection agent):- Fixation time (start of exposure up to fixation or harvest of cells): 10 minSELECTION AGENT (mutation assays):SPINDLE INHIBITOR (cytogenetic assays): ethanol/acetic acidSTAIN (for cytogenetic assays): with 2% Giemsa water solutionNUMBER OF REPLICATIONS: 2NUMBER OF CELLS EVALUATED: 1000DETERMINATION OF CYTOTOXICITY- Method: colometric method
Evaluation criteria:
The criteria for determining a positive result were a concentration-related increased in the number of micronucleated cells and a statistically significant increase over the spontaneous level in at least one treatment schedule. Cells with more than 5 micronuclei were excluded from the evaluation to prevent nuclear fragmentation prvent.
Statistics:
The statistical significance of differences between groups was determined using the X2 test.

Results and discussion

Test results
Species / strain:
mouse lymphoma L5178Y cells
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
None stated
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):negativeThe test substance gave negative responses both with or without metabolic activation.
Executive summary:

Mouse lymphoma L5178Y cells were used in this study. Three types of treatment were carried out parallel: two treatments without metabolic activation with or without a recovery period after 24 h continuous treatment and one treatment with metabolic activation by S9 mix. The concentrations of the test substance were 1000, 500, 250 μg/mL in the three type of treatment. Mitomycin C was used as a positive control in the absence of S9 mix and cyclophosphamide was used as a positive control in the presence of S9 mix.

The test substance gave unequivocal negative responses both with or without metabolic activation or cytotoxicity.