N,N'''-1,6-hexanediylbis[N'-cyanoguanidine]

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

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Test material form:

solid: crystalline

Details on test material:

The dose preparations were corrected for purity (68.9%)

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2

Species / strain 3

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Liver S9 from phenobarbital/beta-naphthaflavone induced male rats

Test concentrations with justification for top dose:

5000, 2500, 1000, 500, 200, 100 ug/plate

Vehicle / solvent:

DMSO

Controls

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

Positive controls:

yes

Positive control substance:

sodium azide

N-ethyl-N-nitro-N-nitrosoguanidine

mitomycin C

other: Acridine, 2-aminoanthracene and Daunamycin

Details on test system and experimental conditions:

HMBDA was assayed using standard plate incorporation protocol both in the presence and absence of liver S9-mix prepared from phenobarbital/beta-naphthaflavone induced rats. HMBDA was subsequently re-tested in all 6 strains over the same dose range. The +S9 phase of the second assay was conducted using the preincubation protocol.

Evaluation criteria:

Test data are considered valid if: (a) the concurrent solvent control data are acceptable (b) the positive control data show unequivocal positive responses (c) at least the lowest test compound dose shows no evidance of toxicity and at least 3 test doses show significant toxicity. Failure of one or more test strain/S9 combinations does not invalidate the data for the remainder of a concurrent experiment. A positive response is achieved when (a) a statistically significant dose related increase in mean number of revertant colonies is obtaines, and/or (b) a 2 fold or greater increase in the mean number of revertant colonies (compared to the concurrent solvent plate) which is statistically signigicant is observed at at least 1 dose level. A negative result is achieve when (a) there is no statistically significant dose related increase in mean number of revertant colonies per plate and (b) in the absence of any such dose response, no increase in colony numbers is observed which exceeds 2x concurrent solvent control. For a positive response to be considered unequivocal i.e. mutagenic the observed effect muct be consistently reproducible.

Statistics:

An assessment of statistical significance was carried out using a one tailed student's t test. The corresponding probability for each dose level was derived by computer using the appropriate degrees of freedom. Values of p<0.01 are treated as significant, with calues of 0.01

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

In 2 separate assays HMBDA did not induce any significant reproducible increases in the observed number of revertant colonies in strains TA1535, TA1537, TA98, TA100, WP2P and WP2P uvrA either in the presence or absence of S9. The positive controls for each experiment induced the expected responses indicating the strains were responding satisfactorily in each case.

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

HMBDA was considered non-mutagenic to bacterial in vitro.