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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:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Version / remarks:
1992
Deviations:
no
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified

Method

Species / strain
Species / strain / cell type:
other: Salmonella typhimurium TA 1535, TA 100, TA 1537, TA 1538 and TA 98
Details on mammalian cell type (if applicable):
The bacterial strains were stored frozen. Before use, strains were transplanted for 3 consecutive times on nutrient agar, incubated at 37 °C + 2 °C for 24 hours and stored 4 °C + 2 °C.
Additional strain / cell type characteristics:
other: histidine auxotroph
Metabolic activation:
with and without
Metabolic activation system:
S9 fractions obtained from livers of male rats which had received Aroclor 1254. Prior to use, all batches of S9 were checked for sterility.
Test concentrations with justification for top dose:
0, 10, 100, 1000, 10.000, 100.000 µg/plate (+/- S9)
Vehicle / solvent:
sterile distilled water
Controlsopen allclose all
Untreated negative controls:
yes
Remarks:
spontaneous mutant control
Negative solvent / vehicle controls:
yes
Remarks:
sterile distilled water
True negative controls:
no
Positive controls:
yes
Positive control substance:
sodium azide
other: (TA100 and TA1535 without metabolic activation)
Positive control substance:
9-aminoacridine
other: (TA1537 without metabolic activation)
Positive control substance:
2-nitrofluorene
other: (TA1538 and TA98 without metabolic activation)
Positive control substance:
other: 2-Aminoanthracene (2AA), 1 µg/plate (all strains with metabolic activation)
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48-72 hours

SELECTION AGENT (mutation assays): histidine

NUMBER OF REPLICATIONS: 1

NUMBER OF PlATES EVALUATED: three per concentration

DETERMINATION OF CYTOTOXICITY
- Method: cloning efficiency
Evaluation criteria:
Validity of:
-sterility control of S9 mix
- sterility at test end
- reliable positive control results
- spontaneous revertant numbers in the following limits:
-- TA 1535: 20 +/-15
-- TA 1538: 20 +/-15
-- TA 1537: 15 +/-10
-- TA 98: 40 +/-25
-- TA 100: 150 +/- 90
Statistics:
no data

Results and discussion

Test results
Key result
Species / strain:
other: S. typhimurium TA 1535, TA 100, TA 1537, TA 1538 and TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
other: first evidence of toxicity at 10000 µg/plate with and without S9
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
MAIN STUDY
Prior to use the master strains were checked for characteristics, viability and spontaneous reversion rate and were all found to be satisfactory.

The test material caused a visible reduction in the growth of the bacterial lawn to all of the strains of Salmonella tested. The first evidence of toxicity was observed at 10000 µg/plate. The test material was tested up to its toxic limit. 

No significant increase in the frequency of revertant colonies of bacteria were recorded for any of the strains of Salmonella used, at any dose level with or without metabolic activation.

All of the positive control chemicals used in the test produced marked increases in the frequency of revertant colonies and the activity of the S9
fraction was found to be satisfactory.

The test material was found to be non-mutagenic under the conditions of this test.

Any other information on results incl. tables

The adopted OECD TG 471 (1997) requires at least 5 test strains and the use of E. coli WP2 strains or Salmonella typhimurium TA 102 to detect certain oxidizing mutagens, cross-linking agents and hydrazines. However, the test substance C8-18 and C18 unsatd. AAPB is not a highly reactive agent and is therefore not expected to be a cross-linking agent, has no oxidizing properties and is no hydrazine. Thus, a test according to former versions of EU Method B.13/14 (Version Commission Directive 92/69/EEC) without E. coli WP2 strains or Salmonella typhimurium TA 102 is considered as sufficient to evaluate the mutagenic activity of AAPB in this bacterial test system.

Applicant's summary and conclusion

Conclusions:
There was no evidence of induced mutant colonies over background, when C8-18 and C18 unsatd. AAPB was tested with and without metabolic activation up to and including cytotoxic concentrations.
Executive summary:

In a reverse gene mutation assay in bacteria according to EU Method B.14 (Version Commission Directive 92/69/EEC), strains TA1535, TA 1537, TA 1538, TA 98 and TA 100 of S. typhimurium were exposed to C8-18 and C18 unsatd. AAPB. Test was performed with concentrations up to and including cytotoxic concentrations in the absence and the presence of mammalian metabolic activation

No evidence of biologically significant mutagenic activity of the test item was found in the presence and absence of metabolic activation, up to and including its cytotoxic limit. The positive controls induced the appropriate responses in the corresponding strains and activity of metabolizing system was confirmed.

There was no evidence of induced mutant colonies over background.

The adopted OECD TG 471 (1997) requires at least 5 test strains and the use of E. coli WP2 strains or Salmonella typhimurium TA 102 to detect certain oxidizing mutagens, cross-linking agents and hydrazines. However, C8-18 and C18 unsatd. AAPB is not a highly reactive agent and is therefore not expected to be a cross-linking agent, has no oxidizing properties and is no hydrazine. Thus, a test according to EU Method B.13/14 (Version Commission Directive 92/69/EEC without E. coli WP2 strains or Salmonella typhimurium TA 102 is considered as sufficient to evaluate the mutagenic activity of AAPB in this bacterial test system.