Benzenesulfonic acid, mono-C11-13-branched alkyl derivs., calcium salts

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

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

Adequacy of study:

key study

Study period:

May 16, 1995-June 30, 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 476 (In Vitro Mammalian Cell Gene Mutation Test)

GLP compliance:

yes (incl. QA statement)

Type of assay:

mammalian cell gene mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Benzenesulfonic acid, C10-13-alkyl derivs., sodium salts

EC Number:

270-115-0

EC Name:

Benzenesulfonic acid, C10-13-alkyl derivs., sodium salts

Cas Number:

68411-30-3

IUPAC Name:

sodium 4-undecylbenzenesulfonate

Constituent 2

Reference substance name:

Benzenesulfonic acid, C10-13 alkyl derivatives, sodium salt

IUPAC Name:

Benzenesulfonic acid, C10-13 alkyl derivatives, sodium salt

Method

Species / strain

Species / strain / cell type:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Metabolic activation system:

S9 from aroclor 1254 induced rat liver

Test concentrations with justification for top dose:

0, 0.6, 1, 1.8, 3, 6 ug/ml without S9
0, 6, 10, 18, 30, 60 ug/ml with S9

Vehicle / solvent:

None

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

no

True negative controls:

yes

Remarks:

H0 medium

Positive controls:

yes

Positive control substance:

other: ethyl methane sulfonate; 3-(20-)methylcholanthrene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium


DURATION
- Preincubation period: 1 week
- Exposure duration: 4 hrs
- Expression time (cells in growth medium): 6 days at 37 degree C for cloning efficiency study, 9 days for mutation assay


STAIN (for cytogenetic assays): Giemsa


NUMBER OF REPLICATIONS: 2

Evaluation criteria:

A test substance was considered mutagenic if a statistically significant dose-related increase in mutant frequency was found in concentrations with greater than 20% survival rate. The mean mutant frequency must also be significantly above the maximum spontaneous mutant frequency.

Statistics:

Statistical significance was determined by the t-test.

Results and discussion

Test results

Species / strain:

Chinese hamster Ovary (CHO)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

preliminary test showed cytotoxicity at >= 50 ug/ml without S9, and >= 100 ug/ml with S9.

Vehicle controls validity:

not examined

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

COMPARISON WITH HISTORICAL CONTROL DATA: In both the studies with and without S9, the mutant frequencies in the treated groups were statistically significantly higher than in the concurrent negative controls. However, the mutant frequencies in the treated groups were not significantly increased when compared to historical negative controls. There was also no dose-response relationship. The increased mutant frequency in treated groups was therefore not considered to be biologically significant.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Results of Test 1 – Without S9 Mix            

Concentration (ug/ml)	Absolute cloning efficiency (%)	Mutant frequency ( x 10^6)
0	82	3 ± 2
0.6	86	7 ± 1
1	85	3 ± 2
1.8	78	5 ± 2
3	86	1 ± 1
6	83	0 ± 1
EMS	83	277 ± 17

Results of Test 1 – With S9 Mix     

Concentration (ug/ml)	Absolute cloning efficiency (%)	Mutant frequency ( x 10^6)
0	90	2 ± 1
6	88	1 ± 1
10	84	9 ± 4
18	78	5 ± 3
30	89	3 ± 2
60	89	7 ± 2
MCA	81	91 ± 9

Results of Test 2 – Without S9 Mix

Concentration (ug/ml)	Absolute cloning efficiency (%)	Mutant frequency ( x 10^6)
0	96	1 ± 1
0.6	92	2 ± 3
1	95	1 ± 1
1.8	93	5 ± 2
3	90	2 ± 1
6	91	6 ± 6
EMS	90	309 ± 20

Results of Test 2 – With S9 Mix     

Concentration (ug/ml)	Absolute cloning efficiency (%)	Mutant frequency ( x 10^6)
0	90	2 ± 1
6	92	7 ± 3
10	88	9 ± 2
18	94	2 ± 1
30	93	2 ± 2
60	90	5 ± 1
MCA	95	89 ± 6

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

The test substance is not mutagenic in either the presence or absence of metabolic activation.

Executive summary:

This study examined the potential of the test substance to cause mutations in mammalian cells. Chinese Hamster Ovary (CHO) cells were exposed to concentrations of 0, 0.6, 1, 1.8, 3, and 6 ug/ml without S9, and 0, 6, 10, 18, 30, and 60 ug/ml with S9. The cells were then examined for cytogenicity and mutation frequency. Ethyl methane sulfonate and 3-(20-)methylcholanthrene were used as positive control substances. Preliminary tests show the test substance was cytogenic at concentrations of 50 ug/ml or greater with metabolic activation, and 100 ug/ml or above without metabolic activation. There was no biologically significant increase in mutation frequency in the treated groups. The test substance is considered not mutagenic to CHO cells both in the presence and absence of S9.