Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
mitotic recombination in Saccharomyces cerevisiae
Type of information:
experimental study
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1979

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The mutagenicity of lead chromate was examined in a battery of microbial tests including: the E. coli PolA+/PolA- survival test, the Salmonella/microsome His+ reversion assay, the E. coli Trp+ reversion test, the E. coli Gal+ forward mutation test, and the S. cerevisiae mitotic recombination assay.
GLP compliance:
not specified
Type of assay:
other: bacterial gene mutation assay; mitotic recombination in Saccharomyces cerevisiae

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Test results
Species / strain:
other: S. typhimurium; E. coli; Saccharomyces cerevisiae
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Remarks on result:
other: Test system: all strains/cell types tested

Any other information on results incl. tables

Lead chromate was positive for mutations in the S. typhimurium His+ reversion assay (at concentrations from 0.2 to 0.4 mg/plate in the presence and absence of S9) and the E. coli Trp+ reversion fluctuation test (at concentrations from 5 uM to 20 uM). Lead chromate was also positive for recombinations in the S. cerevisiae D5 assay at concentrations from 62.5 to 250 ug/ml. Lead chromate had negative responses in the E.coli PolA-/PolA+ assay (at concentrations of 0.2 and 0.3 mg/plate), the E.coli Gal+ forward mutation test (at concentrations from 2.5 to 100 mg/ml), and the E.coli Trp+ reversion plate test (at concentrations of 4 to 60 uM). The authors suggested that the chromate ion is responsible for the observed mutagenicity in Salmonella.

Applicant's summary and conclusion

Conclusions:
Interpretation of results: positive
Executive summary:

The mutagenicity of lead chromate was examined in a battery of microbial tests including: the E. coli PolA+/PolA- survival test, the Salmonella/microsome His+ reversion assay, the E. coli Trp+ reversion test, the E. coli Gal+ forward mutation test, and the S. cerevisiae mitotic recombination assay. Lead chromate was positive for mutations in the S. typhimurium His+ reversion assay (at concentrations from 0.2 to 0.4 mg/plate in the presence and absence of S9) and the E. coli Trp+ reversion fluctuation test (at concentrations from 5 uM to 20 uM). Lead chromate was also positive for recombinations in the S. cerevisiae D5 assay at concentrations from 62.5 to 250 ug/ml. Lead chromate had negative responses in the E.coli PolA-/PolA+ assay (at concentrations of 0.2 and 0.3 mg/plate), the E.coli Gal+ forward mutation test (at concentrations from 2.5 to 100 mg/ml), and the E.coli Trp+ reversion plate test (at concentrations of 4 to 60 uM). The authors suggested that the chromate ion is responsible for the observed mutagenicity in Salmonella.