3-aminobenzenesulphonic acid

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011 - 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

GLP compliance:

yes

Type of assay:

mammalian erythrocyte micronucleus test

Test material

Test material information

Constituent 1

Reference substance name:

3-aminobenzenesulphonic acid

EC Number:

204-473-6

EC Name:

3-aminobenzenesulphonic acid

Cas Number:

121-47-1

Molecular formula:

C6H7NO3S

IUPAC Name:

3-aminobenzene-1-sulfonic acid

Details on test material:

- Name of test material (as cited in study report): 3-aminobenzene sulphonic acid; metanilic acid
- Analytical purity: 99.6% (neutralization titration), 98.3% (HPLC)
- Lot/batch No.: 45JPG

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source (i.e. manufacturer or supplier) and lot/batch number of test material: 45JPG

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
The test substance was analyzed by the study consignee on completion of the animal study, and was confirmed as having been stable throughout the period of the animal study
- Storage condition of test material: Cool dark place (measured value: 2-8°C), tightly sealed

Test animals

Species:

mouse

Strain:

CD-1

Details on species / strain selection:

SPF mice [Crlj:CD1(ICR), Atsugi Breeding Center, Charles River Laboratories Japan, Inc.]

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Institute of Cancer Research
- Age at study initiation: 7 weeks
- Weight at study initiation: 35.8-41.6 g for the males and 28.7-32.2 g for the females
- Assigned to test groups randomly: [no/yes, under following basis: ] yes
- Housing: The animals were housed individually in plastic cages (W 155  D 245  H 150 mm Clea Japan Inc.) provided with floor covering (white flake, Charles River Laboratories Japan), in an animal rearing room (Rearing Room Number: Room 101 for preliminary study,
- Diet (e.g. ad libitum): . Solid feed CRF-1 (Oriental Yeast )Co., Lot No. 110908
- Water (e.g. ad libitum): drinking water (Gotemba City tap water, using water bottles)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24°C
- Humidity (%): (acceptable range 50±20%) 46-56% for the preliminary study and 42-55% for the main study
- Air changes (per hr): 10-15 times per hour
- Photoperiod (hrs dark / hrs light): 12 hours a day (07:00-19:00)/12 hours dark (19:00-7:00)

Administration / exposure

Route of administration:

oral: unspecified

Vehicle:

Sodium carboxymethylcellulose

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

250 mg/kg bw/day (nominal)

Doses / concentrations 2

Dose / conc.:

500 mg/kg bw/day (nominal)

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day (nominal)

Doses / concentrations 4

Dose / conc.:

2 000 mg/kg bw/day (nominal)

Results and discussion

Test results

Key result

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

3-Aminobenzenesulfonic acid was administered at 250, 500, 1000 and 2000 mg/kg/day.. On observation of the general condition, colored urine (orange-yellow) was observed in all males and females in each test substance administration group. There were no deaths. No decrease in body weight related to test substance administration was observed. There were no observed changes in general condition in the negative control group or in the positive control group. There were no observed abnormalities in body weight variation in any test substance administration group compared to the negative control group. There were no observed abnormalities in body weight variation in the positive control group. In the test substance administration groups, the MNPCE frequency was 0.12 ± 0.08% in the 500 mg/kg/day group, 0.14 ± 0.11% in the 1000 mg/kg/day group and 0.11 ± 0.04% in the 2000 mg/kg/day group. Comparing these values with the negative control group of 0.11 ±0.05%, no statistically significant increase or dose dependent change was observed in any of the test substance administration groups. There were no statistically significant (p<0.05) changes in the PCE frequency in 200 total erythrocytes in any test substance administration group compared to the negative control group. The MNPCE frequency in the positive control group was markedly higher than in the negative control group. Furthermore, the MNPCE frequencies in the negative control group and the positive control group were within the range of mean ± 3 S.D. of the study laboratory background data.

Executive summary:

A micronucleus study was conducted using Crlj:CD1(ICR) SPF mice, in order to investigate whether or not 3-aminobenzenesulfonic acid induces chromosomal aberration. In the preliminary study for determining the doses, 250, 500, 1000 and 2000 mg/kg/day,respectively, was administered orally twice at an interval of about 24 hours, to 3 males and 3 females in each group; observation of general condition revealed that, as a result, all males and females in each test substance administration group exhibited colored urine (orange-yellow). There were no deaths. There were no decreases in body weight relating to test substance administration. Based on the above results, there were no deaths in the preliminary study wherein the maximum dose was 2000 mg/kg/day, and so in the main study, 2000 mg/kg/day was set as the high dose, and this was divided by a common ratio of 2 to give doses of 1000 and 500 mg/kg/day; these doses were administered orally twice at an interval of about 24 hours. Bone marrow smear samples were produced and observed about 24 hours after the second administration. Moreover, a negative control group and a positive control group were established; the negative control group received aqueous 0.5% CMC-Na solution at the same administration frequency as in the test substance administration group, and the positive control received a single administration of 1 mg/kg mitomycin C, and at the prescribed time after administration, bone marrow smear samples were prepared and observed. Five male animals were used per group. The results revealed no statistically significant increase in MNPCE frequency in any test substance administration group compared to the negative control group, and no dose-dependent changes were observed. Furthermore, there was no statistically significant change in the PCE frequency in 200 total erythrocytes in any test substance administration group compared to the negative control group. The MNPCE frequencies in the negative control and positive control groups were within the range of mean ± 3 S.D. of the study laboratory background data, and so the test was thought to have been conducted appropriately. It was judged from the above results that, under the conditions of this study, 3-aminobenzenesulfonic acid does not induce chromosomal aberration in the bone marrow of Crlj:CD1(ICR) SPF mice.