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

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

The mutagenicity potential of the test substance was evaluated using the OECD 471 bacterial reverse mutation assay. S. typhimurium strains TA 1535, TA 1537, TA 98 and TA 100, and E. coli WP2 uvr A were tested both with and without S9 activation. Results were negative under all conditions.

In addition, the analogue substance, Benzenesulfonic acid, C10-13 alkyl derivatives, sodium salt was evaluated using OECD 476 for its potential 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.

Link to relevant study records

Reference

Reference 1

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:

Oct. 7, 2010-Nov. 11, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

GLP study conducted on target substance, Benzenesulfonic acid, mono-C11-13-branched alkyl derivs. EC 271-807-5, CAS 68608-88-8.

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Specific details on test material used for the study:

Test Article I.D.: Sulfonic acid Branched Alkylate Derivative
Test Article Batch No.: MIBL008639
Test Article CAS No.: 68608-88-8
Test Article Purity: 100%
Test Article Description: Viscous brown liquid
Storage Conditions: Room temperature, protected from direct sunlight (in foil) without desiccant

Target gene:

Tester strains TA98 and TA1537 are reverted from histidine dependence (auxotrophy) to histidine independence (prototrophy) by frameshift mutagens. Tester strain TA1535 is reverted by mutagens that cause basepair substitutions. Tester strain TA100 is reverted by mutagens that cause both frameshift and basepair substitution mutations. Specificity of the reversion mechanism in E. coli is sensitive to basepair substitution mutations, rather than frameshift mutations.

Species / strain / cell type:

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

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S9 from rat livers induced with Aroclor 1254

Test concentrations with justification for top dose:

The dose levels tested were 1.5, 5.0, 15, 50, 150, 500, 1500 and 5000 μg per plate, based on initial toxicity-mutation assay, which was used to establish the dose-range for the confirmatory mutagenicity assay.

Vehicle / solvent:

Water

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene, 2-nitrofluorene, sodium azide, 9-aminoacridine, methyl methanesulfonate

Details on test system and experimental conditions:

METHOD OF APPLICATION: plate incorporation
0.5 ml of S9 or Sham mix, 100 ul of tester strain, 50 ul of vehicle, and test article or positive control, will be added to 2.0 ml of agar at 45 +/- 2 degrees C.

DURATION
- Preincubation period: 12-14 hrs at 37 +/- 2 degrees C
- Exposure duration: 48-72 hrs at 37 +/- 2 degrees C
- Expression time (cells in growth medium):
- Selection time (if incubation with a selection agent):
- Fixation time (start of exposure up to fixation or harvest of cells):

SELECTION AGENT (mutation assays):
SPINDLE INHIBITOR (cytogenetic assays):
STAIN (for cytogenetic assays):

NUMBER OF REPLICATIONS: 3

NUMBER OF CELLS EVALUATED:

DETERMINATION OF CYTOTOXICITY
- Method: >50% reduction in number of revertants per plate relative to vehicle control

OTHER EXAMINATIONS:
- Determination of polyploidy:
- Determination of endoreplication:
- Other:

OTHER:

Evaluation criteria:

For strains TA1535 and TA1537 - positive if a 3-fold increase in mean revertants as compared to vehicle controls
For strains TA98, TA100, and WP2 uvrA - positive if a 2-fold increase in mean revertants as compared to vehicle controls

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Conclusions:

Interpretation of results (migrated information):
negative

The test substance is negative for gene mutation.

Executive summary:

Benzenesulfonic acid, mono-C11-13-branched alkyl derivs. EC 271-807-5, CAS 68608-88-8 was assessed in an in vitro gene mutation study in bacteria according to OECD 471, the test substance was found to be negative with and without metabolic activation.

Reference 2

Endpoint:

in vitro gene mutation study in mammalian cells

Remarks:

Type of genotoxicity: gene mutation

Type of information:

read-across from supporting substance (structural analogue or surrogate)

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.

Justification for type of information:

Read Across to study conducted on Benzenesulfonic acid, C10-13 alkyl derivatives, sodium salt, As the BAB Acid isneutralized in test medium or under physiological testing conditions, i.e. when tested in vivo, the primary differences between BAB Acid and LAS Na salt are the alkyl chains, branched vs. linear, therefore given their structural and functional similarities, LAS Na salt is a good analogue for read across for instance where data is not available for BAB Acid.

Reason / purpose for cross-reference:

reference to same study

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

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

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.

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'.

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

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 (LAS) 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.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Description of key information

The key study examined the potential of the test substance, analogue linear alkylbenzene sulfonic acid (LAS acid), to cause mutations in the NMRI strain of mice. The primary difference between LAS acid and BABS acid is the alkyl chain, branched vs. linear. Mice (40 of males, 22-25 grams; 40 females, 20-25 grams) were exposure via oral gavage to a single dose of 1122 mg/kg bw.  After 72 hours, cells were taken from the thigh, purified by centrifugation and column chromatography,  Giemsa stained and evaluated for polychromatid erythrocytes (PCEs), the ratio of PCEs to normochromatid  erythrocytes and the number of cells with micronuclei.  No significant increase in the number of PEC with micronuclei were observed.  The test substance is considered negative (not mutagenic) in the mouse micronucleus test.

Link to relevant study records

Reference

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP laboratory study

Justification for type of information:

Read-across based on grouping of substances (category approach) - LAS acid.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

GLP compliance:

yes (incl. QA statement)

Type of assay:

micronucleus assay

Species:

mouse

Strain:

NMRI

Sex:

male/female

Details on test animals or test system and environmental conditions:

Strain NMRI. Animals were approximately 22-26 g (male) and 20-25 g (female) and acclimated for 1 week to the test conditions (20 =/- 3 degrees C, 30-70% relative humidity, 12 hour light/dark cycle). Food was given daily and water was ad libitum. All animals were healthy at the time of test initiation.

Route of administration:

oral: gavage

Vehicle:

NaCl

Duration of treatment / exposure:

72 hours

Frequency of treatment:

single dose

Remarks:

Doses / Concentrations:
1122 mg/kg
Basis:
actual ingested

No. of animals per sex per dose:

40 males and 40 females per dose

Control animals:

yes

Positive control(s):

Endoxan (cyclophosphamid)

Tissues and cell types examined:

Cells were taken from the thigh.

Details of tissue and slide preparation:

Cells were mixed with cattle serum and suspended, then centrifuged. The sediment was then resuspended. The suspension was seperated in a cellulose chromatography column. This was centrifuged, and mixed with fetal calf serum and EDTA. This was air-dried for 24 hrs and stained with Giemsa.

Evaluation criteria:

number of polychromatid erythrocytes (PCE)
ratio of PCE to normochromatid erythrocytes (NCE)
number of cells with micronucleus

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

No significant increases in the number of polychromatic erythrocytes with micronuclei were observed.

Conclusions:

Interpretation of results (migrated information): negative
No significant increases in the number of polychromatic erythrocytes with micronuclei were observed.

Executive summary:

In a study with analogue LAS acid, no significant increases in the number of polychromatic erythrocytes with micronuclei were observed. The test substance is considered negative (not mutagenic) in the mouse micronucleus test.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Short description of key information:

The test substance is negative for gene mutation based on the results of an OECD Guideline 471 test.

The read across substance, Benzenesulfonic acid, C10-13 alkyl derivatives, sodium salt was negative for potential to cause gene mutations in mammalian cells based on the results of an OECD 476 Test.

The read across substance, Linear alkylbenzene sulfonic acid (LAS Acid) did not increase the number of micronuclei based in the results of an OECD 474 test.

Endpoint Conclusion:No adverse effect observed (negative)

Justification for classification or non-classification

Based on the data available on BAB acid, LAS acid and LAS Na salt, BAB acid is not considered to be mutagenic.