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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:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
Study followed OECD 471 guideline and the GLP Regulations. No significant deviations can be observed from the study guidelines; however, strain E. coli WP2 uvrA, or E. coli WP2 uvrA (pKM101), or S. typhimurium TA102 were not included. No data on purity.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
yes (incl. certificate)
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid
Details on test material:
- Name of test material (as cited in study report): 6933-6-20
- Physical state: clear yellow liquid
- Analytical purity: no data
- Impurities (identity and concentrations):
- Lot/batch No.:# 92-014
- Stability under test conditions: no apparent change in the physical state of the test article during storage
- Storage condition of test material: at the room temperature in the clear glass container
- Other:

Method

Species / strain
Species / strain:
other: TA 1535, TA 1537, TA 1538, TA 98 and TA 100
Details on mammalian cell lines (if applicable):
not applicable
Metabolic activation:
with and without
Metabolic activation system:
S-9 fraction of rat liver homogenate obtained from Arcolor 1254-treated Sprague Dawley rats
Test concentrations with justification for top dose:
16.7, 50, 167, 500, 1000 and 1670 µg/plate
Vehicle:
-solvent(s) used: DMSO;
- Justification for choice of solvent: Maron, D.M., J. Katzenellenbogen and B.N. Ames (1981) Compatibility of organic solvents with the Salmonella/Microsome Test, Mutation m., 88:343-350.
Controlsopen allclose all
Solvent controls:
yes
Remarks:
with and without metabolic activation
True negative controls:
no
Positive controls:
yes
Remarks:
without metabolic activation
Positive control substance:
sodium azide
Remarks:
TA1535 and TA100= 10 µg/plate
Solvent controls:
yes
Remarks:
with and without metabolic activation
True negative controls:
no
Positive controls:
yes
Remarks:
without metabolic activation
Positive control substance:
9-aminoacridine
Remarks:
TA1537=150 µg/plate
Solvent controls:
yes
Remarks:
with and without metabolic activation
True negative controls:
no
Positive controls:
yes
Remarks:
without metabolic activation
Positive control substance:
2-nitrofluorene
Remarks:
TA1538 and TA98= 5 µg/plate
Solvent controls:
yes
True negative controls:
no
Positive controls:
yes
Remarks:
with metabolic activation
Positive control substance:
other: 2-anthramine
Remarks:
in all tester strains=2.5 µg/plate
Details on test system and conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: 48h
- Exposure duration: 48h

SELECTION AGENT (mutation assays): biotin and histidine

NUMBER OF REPLICATIONS:
test and control articles (positive and negative): triplicates of all five tested strains
test article in the prescreening: in duplicate

DETERMINATION OF CYTOTOXICITY
- Method: growth inhibition is tested at the following concentrations: 50, 167, 500, 1670 and 5000 µg/plate


Evaluation criteria:
revertant colonies are counted (Artek electronic colony counter interfaced with an IBM PC/AT computer for data acquisation)
-positive result is defined as a statistically significant, dose-dependent increase in the number of histidine-independent revertans with at least one dose level inducing solvent control value
-negative result is defined as the absence of a statistically significant or dose-dependent increase in the number of histidine-independent revertants
-equivocal result is defined when the test article dose not induce a statistically significant, dose dependent increase in revertant frequency, but does induce a revertant frequency at one dose level that is two-fold the spontaneous control value
Statistics:
Statistical analyses were performed using the program developed by Snee and Irr (1981), with significance established at the 95% confidence limit.

Results and discussion

Test results
Species / strain:
other: TA 1535, TA 1537, TA 1538, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity:
not determined
Negative controls valid:
not examined
Positive controls valid:
yes
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Additional information on results:
RANGE-FINDING/SCREENING STUDIES:
- Growth inhibition was observed in strain TA1538 and TA100 at doses of 1670 and 5000 µg/plate without metabolic activation.
- Growth inhibition was observed in strain TA1535, TA1537, TA1538, TA98, TA100 at doses 500, 1000 and /or 1670 µg/plate with and /or without metabolic activation.
- No increase (compared to the negtive control cultures) in revertant frequencies was seen in strain TA1538.
- A dose-dependent increase in revertant frequencies to approx 1.9- to 13- fold control values, were observed in strain TA1538, TA1537, TA98 and TA100 without metabolic activation.

COMPARISON WITH HISTORICAL CONTROL DATA: no data

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive with and without metabolic activation

The results for TETA were positive in the Ames/Salmonella Plate Incorporation Assay under the conditions, and according to, the criteria, of the test protocol.
Executive summary:

Triethylenetetramine (TETA) was tested for potential mutagenic activity using the Salmonella/microsome bacterial mutagenicity assay (Ames test).

In the RANGE-FINDING/SCREENING STUDIES Growth inhibition was observed in strain TA1538 and TA100 at doses of 1670 and 5000 µg/plate without metabolic activation. Growth inhibition was observed in strain TA1535, TA1537, TA1538, TA98, TA100 at doses 500, 1000 and /or 1670 µg/plate with and /or without metabolic activation.

No increase (compared to the negtive control cultures) in revertant frequencies was seen in strain TA1538. A dose-dependent increase in revertant frequencies to approx 1.9- to 13- fold control values, were observed in strain TA1538, TA1537, TA98 and TA100 without metabolic activation. Thus, TETA was considered to be mutagenic in this in vitro bacterial assay.