Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

fixed dose procedure

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

EC Number:

940-594-7

Molecular formula:

C52H86O4S3 , C37H58O3S2

IUPAC Name:

Reaction mass of 2-(1,1-dimethylethyl)-4-{[5-(1,1-dimethylethyl)-4-hydroxy-2-methylphenyl]thio}-5-methylphenyl 3-(dodecylthio)propionate and thiobis[2-(1,1-dimethylethyl)-5-methyl-4,1-phenylene] bis[3-(dodecylthio)propionate]

Test material form:

liquid

Details on test material:

Intended use: Antioxidant for plastics
Appearance: Brown liquid
Storage conditions: Room temperature protected from light
Supplier: Sponsor
Lot number: 102Y1
Expiry date: 30 April 2014
Purity 98.8%

Test animals

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK).
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: approximately eight to nine weeks of age
- Weight at study initiation: bodyweights were in the range 246 to 374 g
- Housing:The cages were solid bottomed polycarbonate cages
with a stainless steel mesh lid. Each cage contained a quantity of autoclaved wood flake
bedding. Cages, food hoppers, water bottles and bedding were changed at appropriate
intervals.
- Diet (e.g. ad libitum): The animals were allowed free access to a standard rodent diet (Rat and Mouse No. 1 Maintenance Diet). This diet contained no added antibiotic or other chemotherapeutic or prophylactic agent.
- Water (e.g. ad libitum):Potable water taken from the public supply was freely available via polycarbonate bottles fitted with sipper tubes.
- Acclimation period: 4 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 23°C
- Humidity (%): 40 to 70%
- Air changes (per hr): The animal room was kept at positive pressure with respect to the outside by its own supply of filtered fresh air, which was passed to atmosphere and not re-circulated.
- Photoperiod (hrs dark / hrs light): Artificial lighting was controlled to give a cycle of 12 hours continuous light and 12 hours continuous dark per 24 hours.

IN-LIFE DATES: From: Day 1 To: Day 15

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure:Dorso-lumbar region of each rat.
- % coverage: 10% of the total body surface area.
- Type of wrap if used: The treatment area (approximately 50 mm x 50 mm) was covered with porous gauze held in place with a non-irritating dressing, and further covered by a waterproof dressing encircled firmly around the trunk of the animal.

REMOVAL OF TEST SUBSTANCE
At the end of the 24 hours exposure period the dressing was carefully removed and the
treated area of skin was washed with a weak solution of detergent, to remove any residual test substance. The treated area was blotted dry with absorbent paper.

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):2 mL/kg bodyweight.
- Constant volume or concentration used: yes

Duration of exposure:

24 Hours

Doses:

1 dose

No. of animals per sex per dose:

A group of ten rats (five males and five females) was treated at 2000 mg/kg bodyweight.

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 15 days
- Frequency of observations and weighing: Animals were observed soon after dosing and at frequent intervals for the remainder of Day 1. On subsequent days, animals were observed once in the morning and again at the end of the experimental day (with the exception of Day 15 - morning only).
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other:

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

There were no deaths and no clinical signs were observed.

Clinical signs:

other: No dermal reactions were observed for any animal.

Gross pathology:

No abnormalities were noted in any animal at the macroscopic examination at study termination on Day 15.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute lethal dermal dose (LD50) to rats of AO-26 was demonstrated to be greater than 2000 mg/kg bodyweight.

Executive summary:

The study was performed to assess the acute dermal toxicity of AO-26 an antioxidant for plastics, to the rat.

A group of ten rats (five males and five females) received a single topical application of the test substance, at a dose level of 2000 mg/kg bodyweight, for 24 hours.

Results

There were no deaths and no clinical signs were observed.

No dermal reactions were observed for any animal.

A bodyweight loss was noted for one female on Day 8 and low bodyweight gains were noted for one female on Day 8 and two females on Day 15. All other animals were considered to have achieved satisfactory bodyweight gains throughout the study.

No abnormalities were noted in any animal at the macroscopic examination at study termination on Day 15.

Conclusion

The acute lethal dermal dose (LD50) to rats of AO-26 was demonstrated to be greater than 2000 mg/kg bodyweight.