Carbamic acid, N-[(1R)-2-hydroxy-1-phenylethyl]-, 1,1-dimethylethyl ester

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

06 October 2015 to 23 December 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

OECD Guidelines for Testing of Chemicals (No.: 402, 24th Feb 1987)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Commission Regulation (EC) No 440/2008, B.3 (L142, 30 May 2008)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1200 (Acute Dermal Toxicity)

Version / remarks:

OPPTS 870.1200 (EPA 712-C-98-192, August, 1998)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Carbamic acid, N-[(1R)-2-hydroxy-1-phenylethyl]-, 1,1-dimethylethyl ester

EC Number:

600-273-1

Cas Number:

102089-74-7

Molecular formula:

C13H19NO3

IUPAC Name:

Carbamic acid, N-[(1R)-2-hydroxy-1-phenylethyl]-, 1,1-dimethylethyl ester

Test material form:

solid: particulate/powder

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

Species and strain: CRL:(WI) rats
Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, D-97633 Sulzfeld
Hygienic level at arrival: SPF
Hygienic level during
the study: Standard housing conditions
Justification of strain: The Wistar rat is one of the standard rodent species used in acute toxicity studies
Number of animals: 5 animals/sex
Sex: Male and female, female rats were nulliparous and non-pregnant.
Age of animals at study start: Young adult rats
Body weight range at dosing: Between 220 g and 252 g
Acclimatization time: 6 days

Husbandry
Animal health: Only healthy animals were used for the study. The veterinarian certified the health status.
Room-Box: 242/2
Housing: Individual caging
Cage type: Type II. polypropylene/polycarbonate
Bedding: Lignocel ¾S Hygienic Animal Bedding (produced by J. Rettenmaier & Söhne GmbH & Co.KG, Germany) was available to animals during the study.
A copy of the Certificate of Analysis is retained in the archives at CiToxLAB Hungary Ltd.
Light: 12 hours daily, from 6.00 a.m. to 6.00 p.m.
Temperature: 20.3 – 24.8 °C
Relative humidity: 32 – 64%
Ventilation: 15-20 air exchanges/hour
Enrichment: Rodents were housed with deep wood sawdust bedding to allow digging and other normal rodent activities.
Temperature and relative humidity were recorded twice daily during the study.

Food and Water Supply
Animals received ssniff® SM R/M "Autoclavable complete diet for rats and mice – breeding and maintenance" produced by ssniff Spezialdiäten GmbH, D-59494 Soest Germany, ad libitum, and tap water from the municipal supply, as for human consumption from a 500 ml bottle, ad libitum. The food is considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study and the water was considered fit for human consumption.
The batch of feed employed in the study was as follows:
 930 3907, expiry date: December 2015
The supplier provided an analytical certificate for the batch used. Copy of the certificates will be archived with the raw data.
Water quality control analysis is performed once every three months and microbiological assessment is performed monthly, by Veszprém County Institute of State Public Health and Medical Officer Service (ÁNTSZ, H-8201 Veszprém, József A.u.36., Hungary). The quality control results are retained in the archives at CiToxLAB Hungary Ltd.

Animal Identification
The individual identification was performed using numbers written on the tail with a marker pen. The numbers were given on the basis of CiToxLAB Hungary Ltd.' s Master File for each animal allocated to the treatment groups. The cages were identified by cards containing information about study code, sex, dose group, cage number and individual animal number.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

A single dermal application was made and was followed by a fourteen-day observation period. Sufficient water was used to dampen the test material to ensure good contact with the skin.

Procedure
The back of each animal was shaved (approximately 10 % area of the total body surface) approximately 24 hours prior to treatment. The test item was applied as a single dose, moistened with water to the shaved skin and remained in contact with the skin for the 24-hour exposure period. Sterile gauze pads were placed on the skin of rats to cover the test item. These gauze pads were kept in contact with the skin using a patch with adhesive hypoallergenic plaster. The entire trunk of the animal was then wrapped with semi occlusive plastic wrap for 24 hours.
At the end of the exposure period, the area of skin treated with the test item was washed with water of body temperature.

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw of the test item

No. of animals per sex per dose:

2 groups, 1 with 5 males, 1 with 5 females

Control animals:

no

Details on study design:

Clinical Observations
Clinical observations were performed on the day of treatment at 1 and 5 hours after application of the test item and once each day for 14 days thereafter. Observations included the skin and fur, eyes and mucous membranes, the respiratory, circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma.

Skin Irritation
Adverse skin reactions at the site of application were recorded daily following the removal of the dressing.

Measurement of Body Weight
The body weights were recorded on Day 0 (before test item administration) and on Days 7 and 14 just before necropsy.

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:

Test item did not cause mortality at the dose level of 2000 mg/kg bw.

Clinical signs:

other: There were no systemic clinical signs noted in any animal throughout the study.

Gross pathology:

No macroscopic observations were noted at a dose level of 2000 mg/kg bw.

Other findings:

No local dermal signs were observed after treatment with the test item during the 14 days observation period.

Applicant's summary and conclusion

Interpretation of results:

study cannot be used for classification

Conclusions:

At the request of the Sponsor the test item was not ranked into classes of Globally Harmonized Classification System. This deviation has no impact on the results or integrity of the study.

The acute dermal median lethal dose (LD50) of the test item N-Boc-D-phenylglycinol was found to be greater than 2000 mg/kg body weight in male and female CRL:(WI) rats.