Guanidine, N,N'''-1,3-propanediylbis-, N-coco alkyl derivs.

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1986

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline conform study according to GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Test material form:

liquid: viscous

Method

Target gene:

histidine and tryptophan reversion

Species / strain

Species / strain / cell type:

other: TA 100, TA 1535, TA 1537, TA 1538, TA 98, WP2uvrA

Metabolic activation:

with and without

Metabolic activation system:

S 9 from rat liver

Test concentrations with justification for top dose:

0; 4; 20; 100; 500; 2500; 5000 µg/plate / first experiment with and without metaboloc activation0; 0.16; 0.8; 4; 20; 100; 500 µg/plate / second experiment with and without metabolic activation

Vehicle / solvent:

Deionised water

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

not specified

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

other: N-Methyl-N'-nitro-N~nitrosoguanidine (MNNG):

Remarks:

without metabolic activation

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

not specified

True negative controls:

no

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

other: 2-aminoanthracene

Remarks:

with metabolic activation

Evaluation criteria:

In the Ames test with Salmonella typhimurium strains the effect of the test compound upon the number of back mutations to histidine prototrophy using histidine auxotrophic mutants is investigated. Using Escherichia coli WP2uvrA, a tryptophan dependent auxotroph strain, mutagenicity is based on -reversion to tryptophan independence. The strains TA 100 and TA 1535 were originally derived by a substitution mutation, the strains TA 1537, TA 1538 and TA 98 by frame shift mutations from histidine prototrophic bacteria. All five Salmonella strains are deficient in the complete structure of their lipopolysaccharide layer and in DNA excision repair system. TA 98 and TA 100 possess a modified postreplication DNA repair system which frequently causes an increase in the rate of mutations. Strain WP2uvrA carries a defect in one of the genes for tryptophan biosynthesis and is deficient in the uvrA system of DNA repair. The reversion can beinduced by a base change (substitution) .

Results and discussion

Test results

Species / strain:

other: TA 100, TA 1535, TA 1537, TA 1538, TA 98, WP2uvrA

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

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 with and without metabolic activationThe diluted test item (concentration 78 %; details see confidential details on test material) was tested for mutagenicity with Salmonella typhimurium strains TA 100, TA 1535, TA 1537, TA 1538, TA 98 and E. coli WP2uvrA in the absence and presence of a metabolic activation system.The diluted test item did not cause a significant increase in the number of revertant colonies with any of the tester strains neither in the absence nor presenceof 5-9 Mix. No dose dependent effect was obtained. It is concluded that the test substance is toxic but not mutagenic in these bacteria1 test systems neither in the absence nor in the presence of an exogenous metabolizing system.

Executive summary:

The diluted test item (concentration 78 %; details see confidential details on test material) was tested for mutagenicity with the strains TA 100, TA 1535, TA 1537, TA 1538, TA 98 of Salmonella typhimurium and Escherichia coli WP2uvrA.

The mutagenicity studies were conducted in the absence and in the presence of a metabolizing system derived from rat liver homogenate. A dose range of 6 different doses from 4-10 000 (1. experiment) and 0.16 µg/plate to 500 µg/plate

(2. experiment) was used. Control plates without mutagen showed that the number. of spontaneous revertant colonies was similar to that described in the literature. All the positiv control compounds gave the expected increase in the number of revertant colonies.

Toxicity: The test compound proved to be very toxic to most of the bacterial strains at 20 or 100 µg/plate. For this reason 500 µg/plate was chosen as top dose level for the mutagenicity study in the repeat experiment.

Mutagenicity: In the absence of the metabolic activation system -the test compound did not show a dose dependent increase in the number of revertants in any of the bacterial strains. Also in the presence of a metabolic activation system, treatment of the cells with the diluted did not result in relevant increases in the number of revertant colonies.

Summarizing, it can be stated that the diluted test item is toxic but not mutagenic in these bacterial test systems neither with nor without exogenous metabolic activation at the dose levels investigated.