Benzene, 1-chloro-2,3-dimethyl-

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 3 Dec 2003 to 30 Dec 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)

Version / remarks:

2001

GLP compliance:

yes

Test type:

up-and-down procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

480-880-4

EC Name:

-

Cas Number:

608-23-1

Molecular formula:

C8H9Cl

IUPAC Name:

1-chloro-2,3-dimethylbenzene

Test material form:

liquid

Details on test material:

- Density: 1.05 g/cm3

Test animals

Species:

rat

Strain:

other: Outbred Albino

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan, Indianapolis, IN
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: at least 49 days
- Weight at study initiation: 201.5-247.5 g
- Fasting period before study: yes
- Housing: individually
- Diet: TEK 7012 Rodent Diet, Harlan Teklad, Madison, WI, ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 2.8
- Humidity (%): 30-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

MAXIMUM DOSE VOLUME APPLIED: 1 ml/100 g bw

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations: twice daily on day of dosing, daily thereafter; weighing on day 0, 7, 14 and at death
- Necropsy of survivors performed: yes

Statistics:

Statistical computer program (AOT425StatPgm) developed by the United States Environmental Protection Agency

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Two out of five animals were found dead in the course of the study (Animal # 1 on Day 12 and Animal # 3 on Day 4). Three out of five animals survived the duration of the study

Clinical signs:

other: In four out of five animals, no clinical manifestations of toxicity were observed. In Animal # 3, piloerection was observed within 4 hours of test substance administration

Gross pathology:

No unusual findings were found during necropsy in all the dosed animals.

Applicant's summary and conclusion

Interpretation of results:

Category 5 based on GHS criteria

Remarks:

toxicity presumably meets criteria for GHS category 5. A defnite conclusion is not possible based on the limit test. Cat 5 is not foreseen in EU CLP Regulation

Conclusions:

Under the conditions of this study, the oral LD50 in rats was > 2000 mg/kg bw

Executive summary:

The test substance, 1-Chloro-2,3-dimethylbenzene, was evaluated for its acute toxcity following oral administration of 2000 mg/kg bw (limit dose) to five female rats. Two deaths were observed in this study. One animal showed clinical signs of toxicity (piloerection). Using OECD guideline 425 as limit test, the test substance was defined to have an estimated LD50 of greater than 2000 mg/kg body weight.