reaction mass of isomers of: C7-9-alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From June 6, 1989 to August 1, 1989

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed according to OECD guideline and GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

(1987)

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:

406-040-9

EC Name:

-

Cas Number:

125643-61-0

Molecular formula:

C24-26 H40-44 O3

IUPAC Name:

C7-9-(branched)-alkyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propanoate

Details on test material:

Physical properties: yellow liquid, insoluble in water
Storage conditions: room temperature
Validity: May 1992
Test material received; May 18, 1989

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: bred and raised on the premises (CIBA-GEIGY Ltd, Animal Production, 4332 Stein, Switzerland)
- Age at study initiation: 7-8 weeks
- Weight at study initiation: 215 to 249 g
- Housing: individually housed in Macrolon cages type 3 with standardized soft wood bedding (Société Parisienne des Sciures, Pantin, France)
- Diet: Rat chow (NAFAG 890 Tox, NAFAG, Gossau/SG, Switzerland) ad libitum
- Water: water ad libitum
- Acclimation period: at least 5 days before exposure

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/ -2°C
- Humidity (%): 55 +/- 10%
- Air changes (per hr): approximately 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12h / 12h

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

Approximately 24 hours before treatment an area on the back of the rat of at least 10% of the body surface was shaved with an electric clipper.
The required amount of the test substance was evenly dispersed on the skin (single application at 2000 mg/kg bw). It was covered with a gauze-lined semiocclusive dressing fastened around the trunk with an adhesive elastic bandage.
After an exposure period of 24 hours the dressing was removed and the skin was cleaned with lukewarm water. Thereafter the skin reaction was appraised repeatedly.

Duration of exposure:

Single exposure, 24 hours.

Doses:

2000 mg/kg bw.

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

Mortality: daily; a.m. and p.m. on working days, a.m. on weekend days
Signs and symptoms: daily
Body weight: immediately before application and on days 7 and 14
Necropsies: The animals were sacrificed and submitted to a gross necropsy at the end of the observation period.

Statistics:

From the body weights, the group means and their standard deviations were calculated.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortalities occurred. Common clinical symptoms including piloerection, hunched posture, and dyspnea were seen; the animals recovered within 5 to 7 days. Body weight was inconspicuous, Necropsy revealed no abnormalities

Mortality:

None.

Clinical signs:

other: Piloerection, abnormal body positions, and dyspnea were seen (common symptoms in acute tests). The animals recovered within 5 to 7 days.

Gross pathology:

At autopsy, no deviations from normal morphology were found.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: other: EU 67/548/EEC and EC/1271/2008

Conclusions:

Upon an acute dermal administration and a 14 day post-treatment observation period, the following LD50 (with 95% confidence limits calculated, where possible) was determined for both sexes: greater than 2000 mg/kg body weight.

Executive summary:

Sprague-Dawley rats of both sexes were treated by single dermal application of 2000 mg/kg bw under semiocclusive conditions according to the OECD TG 402 (1987); treatment was followed by a 14 day post-treatment observation; at the end of this period the animals were sacrificed for the purpose of necropsy. No mortalities occurred. Common clinical symptoms including piloerection, hunched posture, and dyspnea were seen; the animals recovered within 5 to 7 days. Body weight was inconspicuous, Necropsy revealed no abnormalities. The LD50 for both sexes was > 2000 mg/kg bw.