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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: genome mutation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1 Feb 1975 - 28 Feb 1978
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1978
Report date:
1978

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
GLP compliance:
no
Remarks:
The studies were conducted in 1978, before implemenation of OECD Guidelines (1981) and EU Guidelines (1988) as well as GLP principles. The studies were probably conducted according to TSCA guidelines.
Type of assay:
in vitro mammalian cell transformation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
Purity >99%.

Method

Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Details on mammalian cell type (if applicable):
The S-9 fraction from rat liver prepared according to the procedure of Ames Test.
Test concentrations with justification for top dose:
1000, 300, 100, 30 and 10 ug/plate (0.1 ml)
Details on test system and experimental conditions:
all strains/cell types tested

Results and discussion

Test results
Species / strain:
S. typhimurium, other: TA-98, TA-1538 and TA-1537
Metabolic activation:
not specified
Genotoxicity:
ambiguous
Cytotoxicity / choice of top concentrations:
not specified
Vehicle controls validity:
not specified
Untreated negative controls validity:
not specified
True negative controls validity:
not specified
Positive controls validity:
not specified
Remarks on result:
other: Potential mutagen.

Any other information on results incl. tables

TNT exhibited significant increase in the number of revertants at 10 and 30 ug/plate.It produced both base-pair substitution and frame-shift mutations. As little as 10 ug/plate of TNT was mutagenic in the TA-98, TA-1538 and TA-1537 strains. When 30 ug/plate were used, TNT was positive in four test strains; at 300 ug/plate, TNT was positive in all five tester strains.

Conclusion: Potential mutagen.

Applicant's summary and conclusion

Conclusions:
Potential mutagen. Further testing is necessary.