L-Valine, N-(methoxycarbonyl)-3-methyl-

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Between 21 july 1999 and 4 August 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Version / remarks:

adopted 24 February 1987

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Commission Directive 92/69/EEC

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:

-

EC Number:

431-620-3

EC Name:

-

Cas Number:

162537-11-3

Molecular formula:

C8 H15 N O4

IUPAC Name:

2-[(methoxycarbonyl)amino]-3,3-dimethylbutanoic acid

Test material form:

solid: particulate/powder

Details on test material:

Batch number 9D13994

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

CD (Crl: CE (SD) IGS BR)

Sex:

male/female

Details on test animals or test system and environmental conditions:

Test animals were supplied by Charles River (UK) Ltd, Margate, Kent, UK. At the start of the study the males weighed 202 to 252 g and the females 212 to 227 g and were approximately eight to twelve weeks old. After an acclimatisation period of at least five days, the animals were selected at random and given a number unique within the cage by indelible ink-marking on the tail and a number written on a cage card.

The animals were housed in suspended PP cages furnished with woodflakes. They were housed individually during the 24-hour exposure period and in groups of five, by sex, for the remainder of the study. Free access to mains drinking water and food (Rat and Mouse Expanded Diet No.1, Special Diets Services Limited, Witham, Essex, UK) was allowed throughout the study.

The temperature and relative humidity were controlled to remain within target ranges of 19 to 25 C and 30 to 70% respectively. Occasional deviations from these targets were considered not to have affected the purpose or integrity of the study. The rate of air exchange was approximately fifteen changes per hour and the lighting was controlled by a time switch to give twelve hours continuous light and twelve hours darkness.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

other: Arachis oil BP

Details on dermal exposure:

On the day before treatment the back and flanks of each animal were clipped free of hair using veterinary clippers.

Duration of exposure:

24 h

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 animals per sex per dose

Control animals:

no

Details on study design:

The appropriate amount of the test material, moistened with arachis oil BP to form a paste, was pplied uniformly to an area of shorn skin (approximating to 10% of the total body surface area). A piece of surgical gauze was placed over the treatment area and semi-occluded with a piece of self-adhesive bandage. The animals were caged individually for the 24-hour exposure period. Shortly after dosing the dressings were examined to ensure that they were securely in place.

The animals were observed for deaths or overt signs of toxicity 0.5, 1, 2 and 4 hours after dosing and subsequently once daily for fourteen days.

After the 24-hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with distilled water to remove any residual test material. The animals were returned to group housing for the remainder of the study period.

After removal of the dressings and subsequently once daily for fourteen days, the test sites were examined for evidence of primary irritation and scored according to the scale from Draize J H (1977) "Dermal and Eye Toxicity Tests" In: Principles and Procedures for Evaluating the Toxicity of Household Substances, National Academy of Sciences, Washington DC p.31.

Any other skin reactions, if present, were also reported.

Individual bodyweights were recorded prior ro application of the test material on Day 0 and Days 7 and 14.

At the end of the study, the animals were killed by cervical dislocation and subjected to gross pathological examination. This consisted of an external examination and opening of the abdominal and thoracic cavities. The appearance of any macroscopic abnormalities was recorded. No tissues were retained.

Data evaluations included the relationship, if any, between the animal's exposure to the test material and the incidence and severity of all abnormalities including behavioural and clinical observations, gross lesions, bodyweight changes, mortality and any other toxicological effects. Using the mortality data obtained, an estimate of the acute dermal median lethal dose (LD50) of the test material was made.

Statistics:

Not mentioned

Results and discussion

Preliminary study:

Study was a limit test

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

Male: 2000 mg/kg bw; Number of animals: 5; Number of deaths: 0
Female: 2000 mg/kg bw; Number of animals: 5; Number of deaths: 0

Clinical signs:

other: Signs of toxicity related to dose levels: No signs of systemic toxicity were noted during the study period. No toxicologically significant effects on bodyweight were noted during the study.

Gross pathology:

Effects on organs:
No abnormalities were noted at necropsy of animals killed at the end of the study.

Other findings:

Signs of toxicity (local):
No signs of dermal irritation were noted during the study period.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute dermal median lethal dose (LD50) of the test material, BMS 214702-01, in the Sprague-Dawley CD strain rat was found to be greater than 2000 mg/kg bodyweight. No symbol and risk phrase are required according to EU labelling regulations.

Executive summary:

Methods

A study was performed to assess the acute dermal toxicity of the test material in the Sprague-Dawley CD strain rat. The method used followed that described in the OECD Guidelines for Testing of Chemicals No 402 "Acute Dermal Toxicity" (adopted 24 February 1987) and Method B3 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).

The results may be used as a basis for classification and labelling under Annex VI of Council Directive 67/548/EEC (as adapted to technical progress by Commission Directive 93/21/EEC) relating to the classification, packaging and labelling of dangerous substances.

Procedures

A group of ten animals (five males and five females) was given a single 24-hour, semi-occluded dermal application to intact skin at a dose level of 2000 mg/kg bodyweight. The animals were observed for fourteen days after the day of treatment and were then killed for gross pathological examination.

Results

There were no deaths. No signs of systemic toxicity or dermal irritation were noted during the study.

All animals showed an expected gain in bodyweight during the study.

No abnormalities were noted at necropsy.

Conclusions

The acute dermal median lethal dose (LD50) of the test material in the Sprague-Dawley CD strain rat was found to be greater than 2000 mg/kg bodyweight. No symbol and risk phrase are required according to EU labelling regulations.