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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: gene mutation
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2001
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Limited experimental details available.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2001

Materials and methods

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

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): TMAH
- Lot No.: 81021A

Method

Target gene:
- S. typhimurium: Histidine gene
- E. coli: Tryptophan gene
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Metabolic activation:
with and without
Metabolic activation system:
S9-mix
Test concentrations with justification for top dose:
Without S-9 mix:
39.1, 78.1, 156, 313, 625 and 1250 ug/plate (S. typhimurium TA98, TA100, TA1535, TA1537, E. coli WP2 uvrA)
With S-9 mix:
39.1, 78.1, 156, 313, 625 and 1250 ug/plate (S. typhimurium TA98, TA100, TA1535, TA1537); 39.1, 78.1, 156, 313, 625, 1250, 2500, and 5000 ug/plate (E. coli WP2 uvrA)
Vehicle / solvent:
water
Controlsopen allclose all
Negative solvent / vehicle controls:
yes
Remarks:
water
Positive controls:
yes
Positive control substance:
sodium azide
Remarks:
Without S9-mix

Migrated to IUCLID6: 0.5 ug/plate (TA1535); 2-(2-Furyl)-3-(5-nitro-2-furyl) acrylamide, 0.01 ug/plate (TA100, WP2), 0.1 ug/plate (TA98); 9-Aminoacridine hydrochloride, 80 ug/plate (TA1537).
Negative solvent / vehicle controls:
yes
Positive control substance:
other: 2-Aminoanthracene at 1 ug/plate (TA100), 2 ug/plate (TA1535 and TA1537), 10 ug/plate (WP2) or 0.5 ug/plate (TA98).
Details on test system and experimental conditions:
The test was conducted by the preincubation method and triplicate plates were used for each of six different concentrations of the test substance.
Evaluation criteria:
The test substance was considered positive in mutagenicity if the number of revertants found was more than twice the number of those of the solvent (water) control and if reproducible or concentration-dependent increase in the number of the revertants were observed.

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
at 1250 ug/plate and above
Vehicle controls validity:
valid
Positive controls validity:
valid
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

In an AMES test conducted according to OECD guideline 471 and GLP principles, TMAH was found to be negative for mutagenicity, with or without metabolic activation.
Executive summary:

An AMES test was conducted according to OECD guideline 471 and GLP principles. Considerable growth inhibition was observed in all strains treated at the highest concentrations of tetramethylammonium hydroxide. However, no increase in the number of revertant colonies was observed in either strain (S. typhimurium TA98, TA100, TA1535, TA1537, or E.coli WP2 uvrA) treated at any concentrations of tetramethylammonium hydroxide with or without metabolic activation (S9 mix). These results have led to the conclusion that tetramethylammonium hydroxide is negative for mutagenicity in the bacterial reverse mutation assay (Ames test) regardless of metabolic activation.