2-(2H-Benzotriazol-2-yl)-6-(1-methyl-1-phenylethyl)-4-(1,1,3,3-tetramethylbutyl)phenol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29-Oct-1996 to 19-Nov-1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study (OECD test guideline 402)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted on 24-Feb-1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

422-600-5

EC Name:

-

Cas Number:

73936-91-1

Molecular formula:

C29H35N3O

IUPAC Name:

2-(2H-1,2,3-benzotriazol-2-yl)-6-(2-phenylpropan-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol

Details on test material:

- Description: off white solid
- Analytical purity: 99.35-99.45 %
- Storage condition of test material: In the original container at room temperature away from direct sunlight.

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: BRL Ltd, Wölferstrasse 4, 4414 Füllinsdorf, Switzerland
- Age at study initiation: 8 weeks old (males), 11 weeks old (females)
- Weight at study initiation: 231.1-253.2 g (males), 202.3-224.0 g (females)
- Housing: groups of 5 rats/sex in Makrolon type-4 cages
- Diet: pelleted standard rat maintenance diet (Kliba 343, Kliba Mühlen AG, 4303 Kaiseraugst, Switzerland), ad libitum
- Water: tap water, ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 3 °C
- Humidity: 40-70 %
- Air changes: 10-15 changes/hour
- Photoperiod: 12 hours dark / 12 hours light

IN-LIFE DATES: 29-Oct-1996 to 19-Nov-1996

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

other: bidistilled water with a drop of Tween 80

Details on dermal exposure:

TEST SITE
- Area of exposure: 10 % of total body surface area
- Type of wrap: wrap type not indicated, wrap was fixed with an elastic adhesive bandage

REMOVAL OF TEST SUBSTANCE
- Washing: with lukewarm water
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount applied: 4 mL/kg bw
- Concentration: 500 mg/mL
- Constant volume or concentration used: yes (per kg bw)

VEHICLE
- Amount applied: dose volume of 4 mL/kg bw

Duration of exposure:

24 hours

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: mortality and clinical signs were assessed four times on day 1 and once daily thereafter
- Frequency of weighing: on days 1 (pre-administration), 8 and 15.
- Necropsy of survivors performed: yes, including macroscopical examination

Statistics:

The LOGIT-Model could not be used as no deaths occurred.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No deaths occurred during the study.

Clinical signs:

other: Neither clinical signs of systemic toxicity nor local effects of the test item on the skin at the application site were observed during the observation period.

Gross pathology:

No macroscopic findings were noted at necropsy.

Applicant's summary and conclusion

Interpretation of results:

practically nontoxic

Remarks:

Migrated information

Conclusions:

The mean lethal dose of after single dermal administration to rats of both sexes, observed over a period of 14 days, was found to be greater than 2000 mg/kg body weight.

Executive summary:

In a GLP-compliant dermal acute toxicity study according to OECD guideline 402, a group of five male and five female HanIbm:WIST (SPF) rats was treated with test material at 2000 mg/kg by dermal application. The test article was suspended in bi-distilled water and a drop of TWEEN 80 at a concentration of 0.5 g/ml and administered at a volume of 4 ml/kg. Four times during day 1 and once daily during days 2-15 the animals were examined for clinical signs. Mortality and viability were recorded together with clinical signs at the same time intervals. Body weights were recorded on day 1 before administration and on days 8 and 15. All animals were necropsied and examined macroscopically. No deaths occurred during the study period. Neither clinical signs of systemic toxicity nor local effects of the test article on the skin at the application site were observed during the observation period. The body weight of the rats was within the range of physiological variability known for rats of this strain and age. A slight loss of body weight was observed in one female animal during the first and second observation week and in two female animals during the second observation period. No macroscopic organ findings were observed at necropsy. In conclusion, the mean lethal dose of the test item after single dermal administration to rats of both sexes, observed over a period of 14 days, exceeded 2000 mg/kg body weight.