Quaternary ammonium compounds, (C16-18 and C18-unsatd. alkyl)trimethyl, chlorides

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

From 21 August, 2006 to 01 November, 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Information on the category justification can be found in the Quaternary ammonium salts (QAS) category and section 13.2 of IUCLID.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: Commission Directive 2000/32/EC, L1362000, Annex 4D

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Quaternary ammonium compounds, (C16-18 and C18-unsatd. alkyl)trimethyl, chlorides

EC Number:

268-074-9

EC Name:

Quaternary ammonium compounds, (C16-18 and C18-unsatd. alkyl)trimethyl, chlorides

Cas Number:

68002-61-9

Molecular formula:

Representative molecular formula of the major constituents, as the substance is an UVCB: C16 TMAC: C19H42CL1N1 C18 TMAC: C21H46CL1N1 C18-unsatd. TMAC: C21H44CL1N1

IUPAC Name:

Quaternary ammonium compounds, (C16-18 and C18-unsatd. alkyl) trimethyl, chlorides

Method

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:

Experiment I (with and without S9 mix): 0.1, 0.3, 1, 3, 10, 33, 100 and 333 µg/plate
Experiment II (with and without S9 mix): 0.01, 0.03, 0.1, 0.3, 1, 3, 10, 33, 100 and 333 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Deionised water
- Justification for choice of solvent/vehicle: Deionised water was chosen because of its solubility properties and its low toxicity to the bacteria.

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

Spontaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

Deionised water

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

10 µg/plate for TA 1535 and TA 100 (Without metabolic activation)

Controls 2

Untreated negative controls:

yes

Remarks:

Spontaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

Deionised water

Positive controls:

other:

Positive control substance:

other: 4-nitro-o-phenylene-diamine, 10 µg/plate for TA 98, 50 µg/plate for TA 1537 (Without metabolic activation)

Controls 3

Untreated negative controls:

yes

Remarks:

Spontaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

Deionised water

Positive controls:

yes

Positive control substance:

methylmethanesulfonate

Remarks:

3 µL/plate for WP2 uvrA (Without metabolic activation)

Controls 4

Untreated negative controls:

yes

Remarks:

Spontaneous mutation rates

Negative solvent / vehicle controls:

yes

Remarks:

Deionised water

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene, 2.5 µg/plate for TA 1535, TA 1537, TA 98, TA 100 and 10 µg/plate for WP2 uvrA (With metabolic activation)

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: Triplicates

Evaluation criteria:

A test item is considered as a mutagen if there is a biologically relevant increase in the number of revertants exceeding the threshold by twice (strains TA 98, TA 100, and WP2 uvrA) or thrice (strains TA 1535 and TA 1537) the colony count of the corresponding solvent control.

A dose-dependent increase is considered biologically relevant if the threshold is exceeded at more than one concentration.

An increase exceeding the threshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.

A dose-dependent increase in the number of revertant colonies below the threshold is regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony counts remain within the historical range of negative and solvent controls such an increase is not considered biologically relevant.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Reduction in the number of revertants observed in the test groups (i.e., at 100 – 333, 3 – 333 µg/plate with and without S9 mix respectively in experiment I; 100 – 333, 3 – 333 µg/plate respectively with and without S9 mix in experiment II)

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Reduction in the number of revertants observed in the test groups (i.e., at 100 – 333, 3 – 333 µg/plate with and without S9 mix respectively in experiment I; 100 – 333, 3 – 333 µg/plate respectively with and without S9 mix in experiment II)

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Reduction in the number of revertants observed in the test groups (i.e., at 100 – 333, 3 – 333 µg/plate with and without S9 mix respectively in experiment I; 100 – 333, 3 – 333 µg/plate respectively with and without S9 mix in experiment II)

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Reduction in the number of revertants observed in the test groups (i.e., at 100 – 333, 3 – 333 µg/plate with and without S9 mix respectively in experiment I; 100 – 333, 3 – 333 µg/plate respectively with and without S9 mix in experiment II)

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Reduction in the number of revertants observed in the test groups (i.e., at 100 – 333, 3 – 333 µg/plate with and without S9 mix respectively in experiment I; 100 – 333, 3 – 333 µg/plate respectively with and without S9 mix in experiment II)

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Under the study conditions, the source substance was non-mutagenic in S. typhimurium strains TA 1535, TA 1537, TA 98, TA 100 and E. coli strain WP2 uvrA in the reverse mutation assay with and without metabolic activation.

Executive summary:

An in vitro study was conducted to investigate the potential of source substance, C16 TMAC (25% active in water) to induce gene mutations Salmonella typhimurium strains, according to OECD Guideline 471, in compliance with GLP. Salmonella typhimurium strains TA 1535, TA 1537, TA 98 and TA 100 and Escherichia coli strain WP2 uvrA were treated with the source substance using the Ames plate incorporation (pre-experiment and experiment I) and pre-incubation methods (experiment II). The assay was performed in three independent experiments both with and without metabolic activation (S9 mix). Each concentration, including the controls, was tested in triplicate. The concentrations of the source substance ranged from 3 to 5000 µg/plate in the pre-experiment, from 0.1 to 333 µg/plate in experiment I and from 0.01 to 333 µg/plate in experiment II. The plates incubated with the source substance showed reduced background growth in all strains with and without metabolic activation in all experiments. Strong cytotoxic effects, evidenced by a reduction in the number of revertants, occurred in the test groups with and without S9 mix. No substantial increase in revertant colony numbers in any of the five tester strains was observed following treatment with the source substance either in the presence or absence of S9 mix. There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance. All positive control showed a distinct increase in the number of revertant colonies. Under the study conditions, the source substance was determined to be non-mutagenic with and without metabolic activation in the reverse mutation assay (Sokolowski, 2006). Based on the results of the source study, similar non- mutagenic potential can be expected for the target substance.