4,5,6,7-tetrahydro-1H-benzotriazole

Endpoint summary

Description of key information

In rats, the LD50 after oral administration was 2100 mg/kg body weight.

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:

1971

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

no

Test type:

acute toxic class method

Limit test:

no

Species:

rat

Strain:

other: SD derived

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Geigy UK
- Age at study initiation: 5 weeks
- Weight at study initiation: 110g (females), 108g (males)
- Fasting period before study: 18 h
- Housing: single housing
- Diet: ad libitum
- Water: ad libitum
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°F): 70+/-5

Route of administration:

oral: gavage

Vehicle:

polyethylene glycol

Remarks:

PEG 400

Details on oral exposure:

VEHICLE
- Amount of vehicle (if gavage): 10 ml/kg

Doses:

500, 1000, 1500, 2000, 2500, 3000 mg/kg

No. of animals per sex per dose:

5

Statistics:

From the mortality data recorded the LD50 value and its 95% confidence limits were calculated by the method of Litchfield, J.T and Wilcoxon, F. W., 1949, 3. Pharmac. Exp. Ther., 96, 99.

Preliminary study:

In order to determine approximate dose levels for the main study, a range-finding study was carried out using groups of two rats (1 of each sex). The results obtained suggested that the LD50 would be approximately 2000mg/kg.

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 100 mg/kg bw

Based on:

test mat.

95% CL:

> 1 787 - < 2 468

Mortality:

yes, see table below

Clinical signs:

other: Lethargy was observed starting at the lowest dose levels. In addition, lacrimation (at 1500 and 2000 mg/kg) and piloerection (at 2000 mg/kg) was observed in some animals.

Gross pathology:

No Abnormalities detected

MORTALITIES

	mortality
Dose (mg/kg bw)	males	females	combined deaths	%
500	0/5	0/5	0/10	0
1000	0/5	0/5	0/10	0
1500	0/5	1/5	1/10	10
2000	1/5	3/5	4/10	40
2500	4/5	5/5	9/10	90
3000	4/5	4/5	8/10	80

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

adverse effect observed

Dose descriptor:

LD50

Value:

2 100 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Endpoint conclusion:

no study available

Acute toxicity: via dermal route

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Oral acute toxicity

Groups of male and female rats were treated with the test article by gavage at dose levels of 500, 1000, 1500, 2000, 2500 and 3000 mg/kg. The study was performed prior to GLP and OECD guidelines but is reported with sufficient details. Observations were carried out for 14 days at which time the surviving rats were killed and autopsied. The animals showed lethargy, lacrimation and piloerection. No changes were reported during autopsy. Mortalities occurred at 1500 mg/kg and higher. From the mortalities the LD50 was calculated to be 2100 mg/kg bodyweight for both males and females.

Justification for classification or non-classification

Classification, Labeling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for acute toxicity under Regulation (EC) No. 1272/2008.