2-chloro-4-nitrotoluene

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

- only 1000 immature erythrocytes per animal were scored for the incidence of micronucleated erythrocytes

GLP compliance:

yes

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

2-chloro-4-nitrotoluene

EC Number:

204-501-7

EC Name:

2-chloro-4-nitrotoluene

Cas Number:

121-86-8

Molecular formula:

C7H6ClNO2

IUPAC Name:

2-chloro-1-methyl-4-nitrobenzene

Details on test material:

- Name of test material (as cited in study report): 2-Chloro-4-nitrotoluene
- Purity: 99.4 %

Test animals

Species:

mouse

Strain:

NMRI

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann (Borchen, Germany)
- Age at study initiation: approx. 8-12 weeks
- Weight at study initiation: 29-42 g
- Housing: individual (males); 3 animals per cage (females)
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.5-23
- Humidity (%): 43-48
- Air changes (per hr): approx. 10
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

intraperitoneal

Vehicle:

- Vehicle(s)/solvent(s) used: corn oil

Details on exposure:

injection volume: 10 ml/kg bw

Duration of treatment / exposure:

single administration

Post exposure period:

16, 24 or 48 hours

Doses / concentrations

Remarks:

Doses / Concentrations:
1000 mg/kg bw
Basis:
actual ingested

No. of animals per sex per dose:

5

Control animals:

yes, concurrent vehicle

Positive control(s):

Cyclophosphamide: dissolved in physiological saline, single i.p. injection with 10 ml/kg bw

Examinations

Tissues and cell types examined:

bone marrow smears; number of cells scored for micronuclei: 1000 polychromatic erythrocytes (PCEs) per animal; PCE/normochromatic erythrocytes (NCE) ratio determined for 1000 PCEs per animal.

Details of tissue and slide preparation:

according to guideline

Evaluation criteria:

A test was considered positive if there was a relevant and significant increase in the number of micronucleated polychromatic erythrocytes showing micronuclei in comparison to the negative control.

Statistics:

Wilcoxon's non-parametric rank sum test; p<0.001 for significance

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

1000 mg/kg bw: apathy, roughened fur, staggering gait, sternal and lateral recumbency, spasm, twitching, difficulty in breathing and diarrhoea; 1/40 treated animals died during the test period.

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Any other information on results incl. tables

The animals treated with 2-chloro-4-nitrotoluene showed symptoms of toxicity after administration. One of forty animals died before the end of the test due to the acute intraperitoneal toxicity of 1000 mg/kg 2-chloro-4-nitrotoluene.

There was a weakly altered ratio between polychromatic and normochromatic erythrocytes. No indications of a clastogenic effect of 2-chloro-4-nitrotoluene were found after a single intraperitoneal treatment with 1000 mg/kg.

Cyclophosphamide, the positive control, had a clear clastogenic effect, as is shown by the biologically relevant increase in polychromatic erythrocytes with micronuclei. The ratio of polychromatic to normochromatic erythrocytes was not altered.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative

Executive summary:

In the micronucleus test (MNT) equivalent to OECD TG 474 a single intraperitoneal injection of 1000 mg/kg 2-chloro-4-nitrotoluene revealed no indications of a clastogenic effect in male and female mice. Relevant systemic exposure was demonstrated by symptoms of toxicity at 1000 mg/kg bw and a weakly altered ratio between polychromatic and normochromatic erythrocytes.