Dodecylbenzenesulphonic acid

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

There are conclusive but not suffcient data for the classification of substance Dodecylbenzenesulphonic acid/ Dodecylbenzenesulfonic acid with regard to mutagenicity/genetic toxicity. It is concluded that the substance Dodecylbenzenesulphonic acid/ Dodecylbenzenesulfonic acid does not meet the criteria to be classified for human health hazards for Mutagenicity-Genetic Toxicity

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

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

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:

- Species and cell type: Rat (Sprague Dawley strain), male, liver - Quantity: 5 % S9 mix induced with Aroclor 1254

Test concentrations with justification for top dose:

- TA 98: 23.44, 46.88, 93.75, 187.5, 375, 750, 1,500 μg/plate (-)
- TA 98: 5.86, 11.72, 23.44, 46.88, 93.75, 187.5, 375, 750, 1,500, 3,000 μg/plate (+)
- TA 100: 5.86, 11.72, 23.44, 46.88, 93.75, 187.5 μg/plate (-)
- TA 100: 23.44, 46.88, 93.75, 187.5, 375, 750 μg/plate (+)
- TA 1535: 5.86, 11.72, 23.44, 46.88, 93.75, 187.5 μg/plate (-)
- TA 1535: 23.44, 46.88, 93.75, 187.5, 375, 750 μg/plate (+)
- TA 1537: 5.86, 11.72, 23.44, 46.88, 93.75, 187.5 μg/plate (-)
- TA 1537: 23.44, 46.88, 93.75, 187.5, 375, 750 μg/plate (+)
- WP2uvrA: 5.86, 11.72, 23.44, 46.88, 93.75, 187.5 μg/plate (-)
- WP2uvrA: 23.44, 46.88, 93.75, 187.5, 375, 750, 1500 μg/plate (+)

Vehicle / solvent:

Dimethylsulfoxide

Untreated negative controls:

yes

Remarks:

Dimethylsulfoxide

Negative solvent / vehicle controls:

yes

Remarks:

Dimethylsulfoxide

Positive controls:

yes

Positive control substance:

other: 2-Nitrofluorene, Sodium azide, 9-Aminoacridine, 4-Nitroquinoline 1-oxide ,2-Aminoanthracene and Benzo(a)pyrene

Details on test system and experimental conditions:

- Number of replicated: 3 plates/dose - Dose range finding experiment was carried out using dose levels of 8, 40, 200, 1,000, 3,000 and 5,000 μg/plate both in the absence and in the presence of metabolic activation system.- Cytotoxicity: A preliminary toxicity test was performed to define the concentrations to be used for the mutagenicity study.

Evaluation criteria:

The assay was considered valid if the number of spontaneous revertant colonies in vehicle control plates falls within the normal range and the positive control chemicals induce significant increases in the number of mutagen-induced revertant colonies compared to vehicle control. It was judged to be positive if there was a concentration-related increase over the range tested and/or a reproducible increase at one or more concentrations in the number of revertant colonies per plate in at least one strain with or without the metabolic system. In addition, it was judged to have a toxic effect (antibacterial effect) when a clearing or diminution of background lawn, the appearance of micro-colonies, and/or thedecrease more than 50% in the number of colonies compared to that of vehicle control was observed.

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:

cytotoxicity

Remarks:

≥375 μg/plate (+) (TA 100, TA 1535, TA 1537) ≥93.75 μg/plate (-) (TA 100, TA 1535, TA 1537) ≥1500 μg/plate (+) (TA 98) ≥375 μg/plate (-) (TA 98)

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

≥750 μg/plate (+) (WP2 uvr ) 1500 μg/plate (+) (WP2 uvr )

Remarks on result:

other: strain/cell type: TA 98, 100, 1535, 1537 and WP2 uvr A

Remarks:

Migrated from field 'Test system'.

Bacterial tests

A bacterial reverse mutation test was performed in accordance with [OECD TG 471] using Salmonella typhimurium (strains TA98,TA100, TA1535 and TA 1537) and Escherichia coli (strain WP2uvrA) with and without a metabolic activation system. Test doses were as follows:

	5.86, 11.72, 23.44, 46.88, 93.75, 187.5, 375, 750, 1,500, 3,000μg/plate (+/-)

 

Dimethylsulfoxide (DMSO) was used as a vehicle and Sodium azide (SA), 2-Nitrofluorene (2-NF), 9-Aminoacridine (9-AA), 4-Nitroquinoline 1-oxide (4NQO),2-Aminoanthracene (2-AA)andBenzo(a)pyrene (BP)were used as positive control item.In all strains used, there was no increase in the number of revertant colonies compared to the vehicle control at any concentration of dodecylbenzenesulfonic acid either in the presence or absence of metabolic activation system. However, in the first and second experiment, it was observed a clearing or diminution of background lawn, the appearance of micro-colonies, and/or more than 50% decrease in the number of colonies at more than 375 μg/plate and 93.75 μg/plate in TA100, TA1535 and TA1537 strains in the presence and absence of S9 activation, respectively. Also, in TA98 strain, it was observed a clearing or diminution of background lawn, the appearance of micro-colonies, and/or more than 50% decrease in the number of colonies at more than 1500 μg/plate and 375μg/plate in the presence and absence of S9 activation, respectively. InE. coliWP2uvrA strain, the more than 50% decrease in the number of colonies was observed at more than 750μg/plate and at 1500 μg/plate in the presence of S9 activation in the first and second experiment, respectively. The positive controls induced a significant increase in the numbers of revertant colonies indicating the assay was valid.

 

Conclusions:

Interpretation of results :negative

In the presence and absence of metabolic system, no mutation in the Salmonella typhimurium (strains TA 98, TA 100, TA 1535 and TA 1537) and Escherichia coli (strain WP2 uvrA) occurred with dodecylbenzenesulfonic acid .

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

GLP compliance:

yes (incl. QA statement)

Type of assay:

in vitro mammalian chromosome aberration test

Species / strain / cell type:

mammalian cell line, other: Chinese Hamster Lung (CHL)

Metabolic activation:

with and without

Metabolic activation system:

- Species and cell type: Rat (Sprague Dawley strain), male, liver - Quantity: S9 mix induced with Aroclor-1254

Test concentrations with justification for top dose:

- 6hr (+S): 60, 62, 66, 67, 68 μg/mL- 6hr (-S): 70, 72, 74, 76, 78 μg/mL- 22hr (-S): 60, 70, 72, 73, 74 μg/mL

Vehicle / solvent:

Dimethylsulfoxide

Untreated negative controls:

yes

Remarks:

Dimethylsulfoxide

Negative solvent / vehicle controls:

yes

Remarks:

Dimethylsulfoxide

Positive controls:

yes

Remarks:

Cyclophosphamide monohydrate(CPA), ethylmethanesulfonate (EMS)

Remarks:

Positive controls were prepared in sterile distilled water. 100 fold Stock solutions of CPA and EMS were stored at –20 deg. C

Details on test system and experimental conditions:

- Number of replicated: 2 plates/dose
- Culture establishment; The cells were incubated at 37+/- 1 deg C in 5 % CO2 atmosphere. Cells were subcultured twice weekly. Rapidly growing cell cultures were trypsinized, suspended in culture medium and counted. Three series (series I, II and III) of 25 cm^2 culture flask (Falcon) were seeded with 4x10^4 cells each in 5 mL medium and incubated for 3 days before treatment.
- Number of metaphases analyzed: 100
- Criteria for scoring aberrations: Structural- A hundred metaphases that were well spread and had a chromosome count between 23~27 were evaluated for aberrations. The microscope stage co-ordinates were recorded for each aberrant metaphase. Each type of aberration was recorded, and the number of aberrant metaphases (showing one or more aberrations, including/excluding gaps) and total aberrations (including/excluding gaps) were calculated.Numerical-Regardless of the presence of aberrations, an additional 100 metaphases were examined to determine the frequency of diploid (DP), polyploid (PP, ≥ 37 chromosomes), and endoreduplication (ER).

Evaluation criteria:

The result of the study was judged as positive if there was a concentration-related increase or a clear, reproducible and statistically significant increase in the number of cells with chromosome aberrations.

Statistics:

The statistical analyses, according to Richardson et al. (1989), were done using Statistical Analysis System (SAS) program (version 8.2, SAS Institute Inc., Cary,NC). The number of aberrant metaphases (excluding gaps, according to OECD guideline) and number of (PP+ER) were analyzed. Differences were regarded as statistically significant, if P<0.05.1) The vehicle control and test article-treated groups: After carrying out χ2-test, performed Fisher's exact test, if P<0.05.2) Test for dose-response: Cochran-Armitage trend test.3) The vehicle and positive control groups: Fisher's exact test.

Species / strain:

mammalian cell line, other: Chinese Hamster Lung (CHL)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Positive controls validity:

valid

Additional information on results:

In the presence and absence of metabolic system, no significant increase in the number of aberrant metaphase including structural and numerical aberrations in the Dodecylbenzenesulfonic acid-treated groups.

Remarks on result:

other: strain/cell type: Chinese Hamster Lung (CHL)

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results :negative

Dodecylbenzenesulfonic acid did not induce chromosomal aberrations at the concentration range tested in cultured CHL cells under the present experimental conditions.

Reference 3

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

other: published data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Method as described by Ames, McCann & Yamasaki (1975) with some modification (Yahagi, 1975)

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Species / strain / cell type:

S. typhimurium TA 98

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9 mix (polychlorinated biphenyl-induced).

Test concentrations with justification for top dose:

TA 98 and TA 100 : 10, 25, 50, 100, 200 μg/plate (-/+)

Untreated negative controls:

yes

Remarks:

Distilled water or Dimethylsulfoxide

Negative solvent / vehicle controls:

yes

Remarks:

Distilled water or Dimethylsulfoxide

Positive controls:

yes

Remarks:

4-nitroquinoline 1 oxide, N-methyl-N’nitro- N-nitrosoguanidine, benzo[a]pyrene, 2acetylaminofluorene, N-nitrosomethylamine.

Details on test system and experimental conditions:

- Culture establishment : Overnight cultures in nutrient broth were used and 0.1 mL of bacterial suspension was added in 0.5 mL of sodium phosphate buffer (0.1 M, pH 7.4) containing the test substance.The contents were preincubated at 37 deg C for 20 min, and then 2 mL of molten (45 deg C) top agar was added.0.5 mL S-9 mix was added instead of sodium phosphate buffer in a parallel series of experiments.Top agar was overlayed on a plate of minimal glucose agar and revertant colonies were scored after 48 hr incubation at 37 deg C.- S-9 mix contained per mL: 200 μL or 300 μL of S-9 fraction, 8 μmol MgCl2, 33 μmol KCl, 5 μmol glucose-6-phosphate, 4 μmol NADPH and 100 μmol sodium phosphate buffer.

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Positive controls validity:

valid

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Positive controls validity:

valid

Additional information on results:

In the presence and absence of metabolic system, no significant increase in the number of aberrant metaphase including structural and numerical aberrations in the LAS-treated groups. (Table)

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Conclusions:

Interpretation of results :negative

No mutation in the Salmonella typhimurium (strains TA 98, TA 100) occurred with LAS (C10-C14)

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Genetic toxicity in vivo

Link to relevant study records

Reference

Reference 1

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

other: published data

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

GLP compliance:

not specified

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

Details on exposure:

n this study, 40 male and 40 female mice were given a single oral dose by gavage of 1122 mg/kg LAS Acid (read across) and evaluated for chromosome aberrations. Only a single dose has been evaluated which was in the range of the acute oral LD50 value for LAS Acid in rats (LD50 = 1470 mg/kg). Furthermore, slight cytotoxicity has been observed after 48 hours.

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

Additional information on results:

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

Conclusions:

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

Executive summary:

 In this study, 40 male and 40 female mice were given a single oral dose by gavage of 1122 mg/kg LAS Acid (read across) and evaluated for chromosome aberrations. Only a single dose has been evaluated which was in the range of the acute oral LD50 value for LAS Acid in rats (LD50 = 1470 mg/kg). Furthermore, slight cytotoxicity has been observed after 48 hours. No statistically significant or biologically relevant increases in the number of polychromatic erythrocytes with micronuclei were observed; therefore the test material is considered negative for cytogenicity.

Reference 2

Endpoint:

in vivo mammalian germ cell study: cytogenicity / chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

other: published data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Method: Four detergent actives, sodium lauryl sulphate(sodium dodecyl sulphate), DOBS 055, Dobanol 25 sulphate LCU and Dobanol 25 sulphate HCB, were fed to rats in the diet for 90 days at the maximum tolerated dose, 1.13 percent active ingredient in each case. Sodium lauryl sulphate and DOBS 055 were also fed at half this concentration. Chromosome preparations were made from the bone marrow and scored for the presence of rearrangements, chromatid gaps and breaks and isochromatid gaps and breaks.

GLP compliance:

not specified

Type of assay:

chromosome aberration assay

Species:

rat

Strain:

other: Colworth/wistar rat

Sex:

male/female

Details on test animals or test system and environmental conditions:

Weight: weanlings of about 60 g Test substance was fed to six male and female weanling rats in each dose group

Route of administration:

other: Oral (diet)

Duration of treatment / exposure:

90 days

Remarks:

Doses / Concentrations:
1.13%, 0.56%
Basis:
nominal in diet

No. of animals per sex per dose:

six male and female

Control animals:

yes

Positive control(s):

Negative control group of six males and females received the same diet without detergent active and positive control group fed the control diet for 90 days and then given 25 mg/kg by intra-peritoneal injection of cyclophosphamide 20 or 24 h.

Details of tissue and slide preparation:

Two hours before sacrifice the animals were injected intra-peritoneally with 4 mg/kg colchicine, and were killed in a CO2 lethal chamber; one femur was removed and the bone marrow flushed out with 0.9% saline. The bone marrow cells were spun down and resuspended in hypotonic (0.56%) KCl solution at 40 deg C for 20 min. The swollen cells were spun down, resuspended in small amount of 0.56% KCl, and fixative (methanol; glacial acetic acid, 3:1) was added gently to avoid clumping of the cells. The cells were again spun down, resuspended in fresh fixative and fixed for 1 h. After fixation the cells were spun down, resuspended in a small amount of fresh fixative, dropped on to clean microscopic slides and the slides dried in a current of warm air. Slides were stained for 12 min in Giemsa (1:9 in pH 6.8 buffer) and mounted with coverslips.Chromosome preparations were made from eight animals per day over several days; animals from each dose group were distributed evenly over each of the days. This ensured that any variations in the quality of the preparations was spread evenly among the various groups.

Evaluation criteria:

Slide were scanned at X100 to select divisions. Divisions were scored at X 1000 for re-arrangements, chromatid gaps and breaks and isochromatid gaps and breaks. Ten divisions were scored from each slide, and six slides from each animal. There was thus a maximum of 360 divisions scored for each test group. All slides were coded and scored blind.

Sex:

male/female

Genotoxicity:

negative

Additional information on results:

After LAS (C10-C15) were fed to groups of six male and six female Colworth/Wistar rats in the diet at concentrations of 0.56 or 1.13% (equivalent to 280 or 565 mg/kg bw/day) for 90 days, No alteratuons were seen in chromosomes in bone marrow. (Table)

Conclusions:

Interpretation of results : negative
LAS was not exhibit a clastogenic effect under the test condition.

Reference 3

Endpoint:

in vivo mammalian germ cell study: cytogenicity / chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

other: published data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Method: Seven male mice received LAS in the diet for 9 months. Each of the male mice was then mated with 2 female mice that had not been given LAS. The pregnant mice were laparotomized on day 13 of gestation to determine the numbers of luteal bodies, implantations, surviving fetuses, and dead fetuses.

GLP compliance:

not specified

Type of assay:

rodent dominant lethal assay

Species:

mouse

Strain:

other: JCL-ICR

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CLEA Japan, Inc.
- Age at study initiation: 4 weeks
- Housing: individually, except during breeding
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 25 +/- 1
- Humidity (%): 55 +/- 5
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: feed

Details on exposure:

DIET PREPARATION
- Mixing appropriate amounts with (Type of food): feed powder CE-2

Duration of treatment / exposure:

9 months

Frequency of treatment:

daily

Remarks:

Doses / Concentrations:
0.6%, 300 mg/kg bw d
Basis:
nominal in diet

No. of animals per sex per dose:

7

Control animals:

yes

Statistics:

Rohrborn's method.

Sex:

male

Genotoxicity:

negative

Negative controls validity:

valid

Additional information on results:

There were no significant differences in fertility, the mortality of ova and embryos, the number of surviving fetuses, or the index of dominant lethal induction between the experimental groups and the control group.

Dominant Lethal Assay Results

	0.6% in Diet	Control
Number of mating females	14	18
Number pregnant	11	12
No. with dead embryos	6	10
Dead embryos per pregnant female	54.6%	83.3%
No. of corpora lutea	156	161
Corpora lutea per pregnant female	14.2	13.4
No. of implants	148	156
Implants per pregnant female	13.5	13.0
Implants per corpora lutea	94.9	96.9
No. of live fetuses	142	143
Live fetuses per pregnant female	12.9	11.9
Live fetuses per corpora lutea	91.0	88.8
Live fetuses per total implants	96.0	91.7
No. of early dead fetuses	4	12
No. of late dead fetuses	2	1
% of dominant lethals	-4.67	-
% of dominant lethals	-8.33	-

 

Conclusions:

Interpretation of results: negative
The test substance did not cause genetic disorders in mice.
There were no significant differences in fertility, the mortality of ova and embryos, the number of surviving fetuses, or the index of dominant lethal
induction between the experimental groups and the control group.

Reference 4

Endpoint:

in vivo mammalian germ cell study: cytogenicity / chromosome aberration

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

other: published data

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

Method: Groups of 5 male rats were fed a diet containing 0.9% test substance for 9 months. At the end of this period, the animals were sacrificed, and the bone marrow cells examined for chromosome aberrations.

GLP compliance:

not specified

Type of assay:

mammalian germ cell cytogenetic assay

Species:

rat

Strain:

other: Wistar and SD

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: CLEA Japan, Inc.
- Age at study initiation: 4 weeks
- Housing: individually
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 25 +/- 1
- Humidity (%): 55 +/- 5
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: feed

Details on exposure:

DIET PREPARATION
- Mixing appropriate amounts with (Type of food): feed powder CE-2

Duration of treatment / exposure:

9 months

Frequency of treatment:

daily

Remarks:

Doses / Concentrations:
0.9%, 450 mg/kg bw d
Basis:
nominal in diet

No. of animals per sex per dose:

10

Control animals:

yes

Tissues and cell types examined:

femur bone marrow cells

Details of tissue and slide preparation:

Animals were sacrificed by administration of 1 ml/kg of 1% colchine solution. Femurs were then removed, and bone marrow cells washed into centrifuge tubes. The cells were then treated with 0.075 M KCl solution at 37 degree C for 15 min, and then fixed with an acetic acid 1: ethanol 3 solution. Samples were then flame dried and treated with Giemsa.

Evaluation criteria:

Presence and absence of chromosomal aberrations. 50 metaphases per individual.

Statistics:

Rohrborn's method.

Sex:

male

Genotoxicity:

negative

Negative controls validity:

valid

Additional information on results:

No increase in chromosome aberrations was noted.

Chromosome Aberrations

	0.9% in Diet Wister Rats	0.9% in Diet SD Rats	Control	Control
No. of cells with chromatid breaks	0	0	1	0
No. of cells with isochromatid breaks	0	0	0	0
No. of cells with chromatid gaps	3	4	3	4
No. of cells with isochromatid gaps	0	0	0	0
No. of cells with other aberrations	0	0	0	0

 

Conclusions:

Interpretation of results : negative
The test substance is not clastogenic.

Executive summary:

Groups of 5 male rats were fed a diet containing 0.9% test substance for 9 months. At the end of this period, the animals were sacrificed, and the bone marrow cells examined for chromosome aberrations. No increase in chromosome aberrations was seen as compared to controls. The test substance is not clastogenic.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

Additional information from genetic toxicity in vitro:

Mutagenicity

In vitro Studies

Bacterial tests

A bacterial reverse mutation test was performed in accordance with [OECD TG 471] and GLP usingSalmonella typhimurium(strainsTA98,TA100, TA1535and TA 1537) and Escherichia coli (strain WP2uvrA) with and without a metabolic activation system. Test doses were as follows:

5.86, 11.72, 23.44, 46.88, 93.75, 187.5, 375, 750, 1,500, 3,000μg/plate (+/-)

Dimethylsulfoxide (DMSO) was used as a vehicle and Sodium azide (SA), 2-Nitrofluorene (2-NF), 9-Aminoacridine (9-AA), 4-Nitroquinoline 1-oxide (4NQO),2-Aminoanthracene (2-AA)and Benzo(a)pyrene (BP)were used as positive control item.In all strains used, there was no increase in the number of revertant colonies compared to the vehicle control at any concentration of dodecylbenzenesulfonic acid either in the presence or absence of metabolic activation system. However, in the first and second experiment, it was observed a clearing or diminution of background lawn, the appearance of micro-colonies, and/or more than 50% decrease in the number of colonies at more than 375 μg/plate and 93.75 μg/plate in TA100, TA1535 and TA1537 strains in the presence and absence of S9 activation, respectively. Also, in TA98 strain, it was observed a clearing or diminution of background lawn, the appearance of micro-colonies, and/or more than 50% decrease in the number of colonies at more than 1500 μg/plate and 375μg/plate in the presence and absence of S9 activation, respectively. InE. coliWP2uvrA strain, the more than 50% decrease in the number of colonies was observed at more than 750μg/plate and at 1500 μg/plate in the presence of S9 activation in the first and second experiment, respectively. The positive controls induced a significant increase in the numbers of revertant colonies indicating the assay was valid.

In a bacterial reverse mutation assay [OECD TG 471],dodecylbenzesulfonic acid was negative both with and without metabolic activation.

 

Non-bacterial test

The clastogenic potential ofdodecylbenzenesulfonic acidwas testedinaccordance with[OECD TG 473]and GLPin anin vitrochromosome aberration study using Chinese Hamster Lung (CHL) cells, both in the absence and the presence of metabolic activation system (S9 mix).In the determination test of concentration, there is a strong cytotoxicity was observed regardless of S9 mix application.

Cytotoxicity doses were as follows:

1st	6h and 22h treatment:	0, 19.5, 39.1, 78.1, 156.3, 312.5, 625, 1250, 2500, 5000 μg/plate (+/-)
2nd	6h treatment:	0, 40, 50, 60, 70, 80, 100, 120, 140, 160μg/plate(+/-)
	22h treatment:	0, 40, 50, 60, 70, 80μg/plate(-)

 

 Considering these results, test doses were determinated as follows:

6h treatment:	70, 72, 74, 76, 78μg/plate (-) 60, 62, 66, 67, 68μg/plate (+)
22h treatment:	37.5, 60, 70, 72, 73, 74μg/plate(-)

Dimethylsulfoxide (DMSO) was used as a vehicle and cyclophosphamide monohydrate (CPA) and ethylmethansulfonate () were used as positive control item. There was no significant and dose-related increase in the number of metaphases with structural and numerical aberrations at the test item-treated groups compared to that of vehicle control. In the experiment, the frequencies of metaphases with structural aberrations were 0.0, 2.0, 1.5 and 1.5 in the vehicle control, 60, 66 and 68 μg/mL concentrations, respectively. There was no significant change in the number of metaphases with structural aberrations at any dose level tested. The frequency of [polyploid+endoreduplication] in the vehicle control was [1.0+0.0] and there was no significant increase of aberrant metaphase cells at any dodecylbenzenesulfonic acid-treated groups. As expected, there was a clear increase in the number of aberrant metaphase cells in the positive control group (47.0/100 metaphases,p<0.01) indicating that the assay was valid. In the 6-hr treatment, the frequencies of metaphases with structural aberrations were 0.5, 0.0, 1.5 and 3.5 in the vehicle control, 72, 76 and 78 μg/mL concentrations, respectively. There was no significant change in the number of metaphases with structural aberrations at any dose level tested. The frequency of [polyploid+endoreduplication] in the vehicle control was [2.0+0.0] and there was no significant increase of aberrant metaphase cells at any dodecylbenzenesulfonic acid-treated groups.

In the 22-hr treatment, the frequencies of metaphases with structural aberrations were 1.5, 1.5, 2.0 and 0.0 in the vehicle control, 60, 70 and 72 μg/mL concentrations, respectively. There was no significant change in the number of metaphases with structural aberrations at any dose level tested. The frequency of [polyploid+endoreduplication] in the vehicle control was [1.0+0.0] and there was no significant increase of aberrant metaphase cells at any dodecylbenzenesulfonic acid-treated groups. There was a clear increase in the number of aberrant metaphases in the positive control groups, both with the 6-hr (14.5/100 metaphases,p<0.01) and the 22-hr treatments (29.0/100 metaphases,p<0.01) indicating that the assay was valid.

An in vitro test chromosome aberration test [OECD TG 473] using Chinese hamster lung cells (CHL) dodecylbenzesulfonic acid was negative with and without metabolic activation.

Vivo test

No mutagenic activity of Benzenesulfonic acid, 4-C10-13-sec-alkyl derivs.as a surrogate for Benzenesulfonic acid, dodecyl- (CAS #27176-8) detected in the reliable study of Fedtke, N 1991.

 

In this study, 40 male and 40 female mice were given a single oral dose by gavage of 1122 mg/kg LAS Acid (read across) and evaluated for chromosome aberrations. Only a single dose has been evaluated which was in the range of the acute oral LD50 value for LAS Acid in rats (LD50 = 1470 mg/kg). Furthermore, slight cytotoxicity has been observed after 48 hours. No statistically significant or biologically relevant increases in the number of polychromatic erythrocytes with micronuclei were observed; therefore the test material is considered negative for cytogenicity.

 

Justification for classification or non-classification

Based on the hazard assessment of Dodecylbenzenesulphonic acid/ Dodecylbenzenesulfonic acid in section 2.1 and 2.2. in IUCLID 6, available data for the substance and following the “Guidance on Information Requirement and Chemical Safety Assessment R.8. Characterisation of dose [concentration]- response for human health” andaccording to the criteria described in Directive 67/548 and in the CLP Regulation:

 

 

	Mutagenicity-Genetic Toxicity Muta. Cat. 1; R46 May cause heritable genetic damage. Muta. Cat. 2; R46 May cause heritable genetic damage. Muta. Cat. 3; R68 Possible risk of irreversible effects.
CLP	Germ cell mutagenicity Muta. 1A Muta. 1B Muta. 2 H340: May cause genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>. H341: Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.

 

 

It is concluded that the substance Dodecylbenzenesulphonic acid/ Dodecylbenzenesulfonic acid does not meet the criteria to be classified for human health hazards for Mutagenicity-Genetic Toxicity