(hexadecylamidopropyl)trimethylammonium chloride

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-04-26 to 1999-06-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

(adopted 1997)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

(hexadecylamidopropyl)trimethylammonium chloride

EC Number:

257-104-6

EC Name:

(hexadecylamidopropyl)trimethylammonium chloride

Cas Number:

51277-96-4

Molecular formula:

C22H47N2O.Cl

IUPAC Name:

(3-hexadecanamidopropyl)trimethylazanium chloride

Test material form:

other: waxy solid

Method

Target gene:

Histidine locus

Species / strain

Species / strain / cell type:

S. typhimurium, other: TA97a, TA98, TA100, TA102, and TA1535

Metabolic activation:

with and without

Metabolic activation system:

rat liver S9-mix

Test concentrations with justification for top dose:

range finding study: TA98 and TA100 with and without S9: 0.005, 0.0 1, 0.05, 0.1, 0.5, 1, and 5 mg/plateInitial and repeat plate incorporation assayall strains - S9: 0.0001, 0.0003, 0.0008, 0.00 1, 0.003, 0.008, and 0.01 mg/plateall strains + S9: 0.0008, 0.00 1, 0.003, 0.008, 0.01,0.03, and 0.05 mg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO- Justification for choice of solvent/vehicle: solubility pretest

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

2-acetylaminofluorene

2-nitrofluorene

sodium azide

mitomycin C

other: 2-aminoanthracene, Danthron - with metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)DURATION- Exposure duration: 48-72 hNUMBER OF REPLICATIONS: 3 (test substance, positive controls), 9 negative controls in 2 independent assaysDETERMINATION OF CYTOTOXICITY- Method: decrease in the number of revertant colonies per plate and/or thinning or disappearance of the background bacterial lawn, or appearance of pinhead colonies in treated cultures.

Evaluation criteria:

A test substance producing no biologically relevant positive response in any one of the bacterial strains tested is considered to be non-mutagenic in this system.Test materials are considered to be mutagenic if at least one tester strain of Salmonella typhimurium shows at least a doubling in the mean number of revertans per plate over the appropriate control in tester strains TA97a, TA98, TA100, and TA102; in TA1535, a positive response is a threefold increase in revertant. A dose respons effect must also be observed over at least three concentrations of the test material in any tester strain.

Results and discussion

Test results

Key result

Species / strain:

S. typhimurium, other: TA97a, TA98, TA100, TA102, and TA1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS- Effects of pH: no data- Effects of osmolality: no data- Evaporation from medium: no data- Precipitation: no precipitation described - Other confounding effects: noRANGE-FINDING/SCREENING STUDIES:A range-finding study was conducted in tester strains TA98 and TA100. COMPARISON WITH HISTORICAL CONTROL DATA:range finding study: Although the spontaneous mutation frequency of the medium control for tester strain TA98 was lower than the minimal acceptable level of 15 revertants/plate, the S9 control was in the acceptable range. All other positive and negative controls were within the acceptable ranges for tester strains TA98 and TAl00.ADDITIONAL INFORMATION ON CYTOTOXICITY:Toxicity was observed in tester strains TA98 and TA100 at 0.01 mg/plate in the absence of S9, and at 0.05 mg/plate in the presence of S9. Because of the variability in toxicity with S9, 0.01 mg/plate was selected as the highest dose level of test substance for definitive testing in the absence of S9, and 0.05 mg/plate was selected as the highest dose level for definitive testing in the presence of S9.

Applicant's summary and conclusion

Conclusions:

C16 Alkylamidopropyltrimethylammonium Chloride was evaluated in the bacterial reverse mutation assay (Ames test) using Salmonella typhimurium tester strains TA97a, TA98, TA100, TA102, and TA1535 in the presence and absence of rat liver S9 mix. Under the conditions of the study, the test substance was negative for mutagenic potential.

Executive summary:

In a reverse gene mutation assay in bacteria according to OECD guideline 471 (adopted 21 July 1997), Salmonella typhimurium strains TA97a, TA98, TA100, TA102 and TA1535 were exposed to C16 Alkylamidopropyltrimethylammonium Chloride  in DMSO in concentrations of 0 (control), 0.1, 0.3, 0.8, 1, 3, 8, and 10 µg/plate in all strains in the absence of mammalian metabolic activation (rat liver S9 mix) and in concentrations of 0 (control), 0.8, 1, 3, 8, 10, 30, and 50 µg/plate in all strains in the presence of mammalian metabolic activation (rat liver S9 mix). The assay was performed using the plate incorporation method.

The test substance was tested up to cytotoxic concentrations. Cytotoxic effects were noted in strains TA98 and TA100 starting at 10 µg/plate without metabolic activation, and at 50 µg/plate in with metabolic activation. Precipitation was not observed.The positive controls induced the appropriate responses in the corresponding strains. The mean numbers of revertant colonies in the negative controls were within the ranges of the historical control data.

There was no evidence of an increase in the number of revertant colonies that exceeded twice background in any of the five tester strains (TA97a, TA98, TA 100, TA102, or TA1 535) examined at dose levels up to 10 µg/plate in the absence of a metabolic activation source (S9) or at dose levels up to 50 µg/plate in the presence of S9. Therefore, test substance was considered to be non-genotoxic (non-mutagenic) in Salmonella tester strains TA97a, TA98, TA100, TA102, and TA 1535 under the conditions employed (plate incorporation assay).

There was no evidence of induced mutant colonies over background.

Under the conditions of the study, the test substance was negative for mutagenic potential.