Registration Dossier

Administrative data

Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Between 17 January 1995 and 31 January 1995
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted according to OECD guidelines and in compliance with GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method B.3 (Acute Toxicity (Dermal))
Deviations:
no
Qualifier:
according to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Test type:
standard acute method
Limit test:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid
Details on test material:
Identity: Salicynalva
Chemical name: 2-Phenylhexanenitrile
Appearance: Light yellow liquid
Storage conditions: Room temperature in dark
Date received: 28 September 1994

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
Equal numbers of healthy male and female CD rats of Sprague-Dawley origin (Hsd/Ola:SpragueDawley(CD)) were obtained from Harlan Olac Ltd., Bicester, Oxon, England.
They were in the weight range of 215 to 241 g and approximately seven to ten weeks of age prior to dosing (Day 1). All the rats were acclimatised to the experimental environment for a period of five days prior to the start of the study.
The rats were allocated without conscious bias to cages within the treatment groups. They were housed individually in metal cages with wire mesh floors in Building R14 Room 6.
A standard laboratory rodent diet (Biosure LAD 1) and drinking water were provided ad libitum.
Each batch of diet used for the study was analysed for certain nutrients, possible contaminants and microorganisms .
Results of routine physical and chemical examination of drinking water at source as conducted, usually weekly by the supplier, are made available to Huntingdon Research Centre Ltd. as quarterly summaries.
Animal room temperature was set to achieve a temperature of 22 ± 3°C. Relative humidity was not controlled but was anticipated to be in the range 30 - 70%. Permanent daily recordings of these parameters were made and these are archived with other Department raw data. Any slight deviation in temperature and humidity that may have occurred had no impact on the study in the opinion of the Study Director. Air exchange was maintained at 10 to 15 air changes per hour and lighting controlled by means of a time switch to provide 12 hours of artificial light (0700 - 1900 hours) in each 24-hour period.
Each animal was identified by cage number and ear punching. Each cage was identified by a coloured label displaying the dose level, study schedule number, animal mark and the initials of the Study Director and Home Office license.

Administration / exposure

Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
A group of ten rats (five males and five females) was treated at 2.0 g/kg bodyweight. The test substance was applied by spreading it evenly over the prepared skin
Duration of exposure:
24 hours
Doses:
2.0 g/kg bodyweight.
No. of animals per sex per dose:
five males
five females
Control animals:
not required
Details on study design:
TREATMENT PROCEDURE
A group of ten rats (five males and five females) was treated at 2.0 g/kg bodyweight.
One day prior to treatment, hair was removed from the dorso-lumbar region of each rat with electric clippers exposing an area equivalent to approximately 10% of the total body surface.
The test substance was applied by spreading it evenly over the prepared skin. The treated area (approximately 50 mm x 50 mm) was then promptly covered with gauze which was held in place with a non-irritative dressing encircled firmly around the trunk.
At the end of the 24 hours exposure period, the dressings were carefully removed and the treated area of skin was washed with warm (30° to 40°C) water and blotted dry with absorbent paper.
The day of dosing was designated Day 1.

Control animals
No control animals were included in this study.

OBSERVATIONS
Mortality
Cages of rats were checked at least twice daily for any mortalities.
Clinical signs
Animals were observed soon after dosing and at frequent intervals for the remainder of Day 1 (a period of six hours). 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). This latter observation was at approximately 16: 30 hours on week days or 11: 30 hours on Saturdays and Sundays. The nature and severity of the clinical signs and time were recorded at each observation.
All animals were observed for 14 days after dosing.

Dermal responses
Local dermal irritation at the treatment site was assessed daily using the following numerical system:

Erythema and Eschar Formation Value

No erythema 0
Slight erythema 1
Well-defined erythema 2
Moderate to severe erythema 3
Severe erythema (beet redness) to slight eschar formation (injuries in depth) 4

Oedema Formation

No oedema 0
Slight oedema 1
Well-defined oedema (edges of area well-defined by definite raising) 2
Moderate oedema (raised approximately 1 millimetre) 3
Severe oedema (raised more than 1 millimetre and extending beyond the area of exposure) 4

Bodyweight
Individual bodyweights were recorded on Days 1 (prior to dosing), 8 and 15. Individual weekly bodyweight changes were calculated.

Macroscopic examination
All animals were killed on Day 15 by cervical dislocation and were subjected to a macroscopic examination which consisted of opening the abdominal and thoracic cavities. The macroscopIc appearance of all examined tissues was recorded.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LD50
Effect level:
> 2 000 mg/kg bw
Based on:
test mat.
Mortality:
There were no deaths following a single dermal application of Salicynalva to a group of ten rats (five males and five females) at a dosage of 2.0 g/kg bodyweight.

Clinical signs:
There were no signs of systemic reaction to treatment.
Body weight:
Slightly low bodyweight gains were recorded for three males and three females on Day 8 and in one male and two females on Day 15. In addition, two females showed a slight bodyweight loss on Day 8 and one female showed no body weight gain at Day 15. Such changes are not unusual and are commonly associated with the treatment procedure. Remaining males achieved anticipated bodyweight gains throughout the study.
Gross pathology:
No macroscopic abnormalities were observed for animals killed on Day 15.
Other findings:
With the exception of a residual black staining from the test substance on the treatment sites of some animals there were no other dermal changes observed in any animal throughout the dose period (scores of zero for erythema and oedema were recorded for all animals).

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information LD50 >=2000 mg/kg bw Criteria used for interpretation of results: EU
Conclusions:
The acute lethal dermal dose to rats of Salicynalva was found to be >= 2000 mg/kg bodyweight.
Executive summary:

A study was performed to assess the acute dermal toxicity of Salicynalva to the rat. The method followed was that described in EEC Methods for the determination of toxicity, Annex to Directive 92/69/EEC (OJ No. L383A, 29. 12. 92), Part B, Method B.3. Acute toxicity (dermal) and OECD Guideline for Testing of Chemicals No. 402 "Acute Dermal Toxicity". Adopted: 24 February 1987. A group of ten rats (five males and five females) was given a single occlusive dermal application of the test substance, as supplied by the sponsor and administered at a dosage of 2.0 g/kg bodyweight, no vehicle was used. All animals were killed and examined macroscopically on Day 15, the end of the observation period. There were no deaths and no signs of systemic reaction to treatment. With the exception of a residual black staining from the test substance on the treatment sites of some animals, there were no other dermal changes observed in any animal throughout the dose period (scores of zero for erythema and oedema were recorded for all animals). Slightly low bodyweight gains were recorded for three males and three females on Day 8, with a similar trend noted for one male and two females on Day 15. In addition, two females showed a slight bodyweight loss on Day 8 and one female showed no bodyweight gain on Day 15. The remaining animals achieved anticipated bodyweight gains throughout the study. No abnormalities were recorded at the macroscopic examination on Day 15.

The acute lethal dermal dose to rats of Salicynalva was found to be greater than 2000 mg/kg bodyweight.