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

Endpoint summary

Description of key information

The oral and dermal LD50 values in rats were > 2000 mg/kg bw in reliable studies according to OECD guidelines 425 and 402.

Key value for chemical safety assessment

Acute toxicity: via oral route

Link to relevant study records

Reference

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

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

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

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

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.

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.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

Key study is reliable without restrictions

Acute toxicity: via inhalation route

Link to relevant study records

Reference

Endpoint:

acute toxicity: inhalation

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Link to relevant study records

Reference

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 17 Dec 2003 to 31 Dec 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Millbrook Breeding Labs, Amherst, MA, USA
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 12-15 weeks
- Weight at study initiation: 2.00-2.36 kg
- Fasting period before study: no
- Housing: individually
- Diet: TEK 8630 Rabbit Diet, Harlan Teklad, Madison, WI, USA, ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3
- Humidity (%): 30-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: approx. 10 % of body surface

REMOVAL OF TEST SUBSTANCE
- Washing (if done): with USP water for injection
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bw

Duration of exposure:

24 h

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations: frequently during the first day, careful clinical observations at least once daily; weighing: days 0, 7 and 14
- Necropsy of survivors performed: Yes

Statistics:

not performed

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No effects

Clinical signs:

other: No effects

Gross pathology:

No effects

Interpretation of results:

GHS criteria not met

Conclusions:

Under the conditions of this study, the dermal LD50 in rabbits was > 2000 mg/kg bw.

Executive summary:

The test substance, 1-chloro-2,3-dimethylbenzene, was evaluated for its potential to produce systemic toxicity or death after a single topical 24-hour application to the skin of albino rabbits at a dose of 2000 mg/kg bw. No animal died during the course of the study, therefore the test substance is considered non-toxic according to the criteria of the study protocol.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

discriminating dose

Value:

2 000 mg/kg bw

Quality of whole database:

Key study is reliable without restrictions

Additional information

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

The test substance, 1-chloro-2,3-dimethylbenzene, was evaluated for its acute toxicity after a single topical 24-hour application to the skin of albino rabbits at a dose of 2000 mg/kg bw. No animal died during the course of the study, therefore the test substance is considered non-toxic according to the criteria of the study protocol. This result is supported by a less reliable study.

Justification for classification or non-classification

Due to LD50 values of > 2000 mg/kg bw for oral and dermal exposure, no classification for acute toxicity is required according to the criteria of Regulation (EC) No 1272/2008.