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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1979

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
not specified
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
impurity
Test material form:
not specified
Details on test material:
not specified
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Pyrogallol was purchased from Merck.
- Expiration date of the lot/batch: not specified
- Purity test date: not specified

RADIOLABELLING INFORMATION (if applicable) not applicable
- Radiochemical purity: -
- Specific activity: -
- Locations of the label: -
- Expiration date of radiochemical substance: -

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: not specified
- Stability under test conditions: not specified
- Solubility and stability of the test substance in the solvent/vehicle: not specified
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not specified

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
- Treatment of test material prior to testing: Pyrogallol was pro analysi grade,
- Preliminary purification step (if any): as reported
- Final dilution of a dissolved solid, stock liquid or gel:
- Final preparation of a solid:

FORM AS APPLIED IN THE TEST (if different from that of starting material)

TYPE OF BIOCIDE/PESTICIDE FORMULATION (if applicable) not applicable

OTHER SPECIFICS: not specified

Method

Target gene:
L-histidine
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 100
Additional strain / cell type characteristics:
not specified
Species / strain / cell type:
S. typhimurium TA 1537
Additional strain / cell type characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
Liver homogenate fraction mix (S9 mix)
Test concentrations with justification for top dose:
200, 50, 20 and 5 micro/g (Ames et al. 1975)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: water
- Justification for choice of solvent/vehicle: not specified
Controls
Untreated negative controls:
not specified
Negative solvent / vehicle controls:
yes
Remarks:
water (with and without metabolic activation)
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
N-ethyl-N-nitro-N-nitrosoguanidine
benzo(a)pyrene
other: 9-aminoacridine
Details on test system and experimental conditions:
The test was performed according to Ames et al. 1975 and no infomation related to eventual deviations were reported.

METHOD OF APPLICATION: in medium; in agar (plate incorporation); preincubation; in suspension; as impregnation on paper disk see above
- Cell density at seeding (if applicable): see above

DURATION
- Preincubation period: see above
- Exposure duration: see above
- Expression time (cells in growth medium): see above
- Selection time (if incubation with a selection agent): see above
- Fixation time (start of exposure up to fixation or harvest of cells): see above

SELECTION AGENT (mutation assays): see above

SPINDLE INHIBITOR (cytogenetic assays): see above

STAIN (for cytogenetic assays): see above

NUMBER OF REPLICATIONS: 2 for each strain

METHODS OF SLIDE PREPARATION AND STAINING TECHNIQUE USED: see above

NUMBER OF CELLS EVALUATED: see above

NUMBER OF METAPHASE SPREADS ANALYSED PER DOSE (if in vitro cytogenicity study in mammalian cells): see above

CRITERIA FOR MICRONUCLEUS IDENTIFICATION: not relevant

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index; cloning efficiency; relative total growth; other: see above
- Any supplementary information relevant to cytotoxicity: see above

OTHER EXAMINATIONS:
- Determination of polyploidy: see above
- Determination of endoreplication: see above
- Methods, such as kinetochore antibody binding, to characterize whether micronuclei contain whole or fragmented chromosomes (if applicable): see above

- OTHER: see above
Rationale for test conditions:
The Ames plate test was carried out as described by Ames et al.
Evaluation criteria:
Viable counts were carried out by spreading 0.2 ml of the diluted cultures on triplicate synthetic-agar plates containing in addition L-histidine (20 microg/ml) and biotin (3 microg/ml). The plates were incubated for 48 h at 37°C and the number of colonies was then determined.
Statistics:
not specified

Results and discussion

Test resultsopen allclose all
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
not specified
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
Positive controls validity:
not specified

Any other information on results incl. tables

Examination of the results obtained from the colicine-induction assay on pyrogallol shows that the substances induced

colicine E2 when tested directly on the test plates.

It has been suggested (Ben Gurion, 1978) that the colicine-induction test could be used as a screening test for mutagenic and carcinogenic substances.

To verify that pyrogallol is not only inducer of colicine but is mutagenic as well, it was also tested in the Ames test.

The observation that pyrogallol does not mutagenize strain TA98 when tested directly on the plates

(Rahimtula, 1977) was confirmed. But when pyrogallol was tested with additional tester strains, it was found to be mutagenic for strain TA1537 as well as for strain TA100. Pyrogallol mutagenicity was reduced in the presence of ratliver

microsomal preparation on the plates, probably as a result of an interaction with the mixture which reduced its activity towards the bacteria.

Applicant's summary and conclusion

Conclusions:
Pyrogallol tested in Salmonella typhimurium (strains TA100 and TA1537) at doses 5-200 microg/plate (in presence and absence of metabolic activation) resulted as mutagenic.