(2Z)-2-phenylhex-2-enenitrile

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02-09-2008 to 23-09-2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP. All relevant validity criteria were met; note that for local effects only: the reshaving at day 8 is a deviation is suggestive of effects that are non-test item related, which limits the reliability for assessment.

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Report date:

2008

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

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:

482-160-5

EC Name:

-

Cas Number:

130786-09-3

Molecular formula:

C12H13N

IUPAC Name:

(2Z)-2-phenylhex-2-enenitrile

Test material form:

liquid

Details on test material:

- Physical state: liquid
- Storage condition of test material: Refrigerator (range of 5 ± 3 °C), in the dark under nitrogen
- Other: colourless

Test animals

Species:

rat

Strain:

Wistar

Remarks:

HanRcc: WIST (SPF) strain

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Recognised supplier
- Age at study initiation: 9 - 11 weeks.
- Weight at study initiation: 197.3 - 264.0 g; the weight variation did not exceed ±20% of the mean weight for each sex.
- Fasting period before study: Not applicable
- Housing: during acclimation: group housed by sex; during study: individually housed in Makrolon type-4 cages furnished with softwood bedding.
- Diet (e.g. ad libitum): Certified diet from recognised supplier, provided ad libitum.
- Water (e.g. ad libitum): ad libitum.
- Acclimation period: At least 5 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 °C
- Humidity (%): 30 - 70%
- Air changes (per hr): 10 to 15 air changes per hour
- Photoperiod: 12 h light / 12 h dark

IN-LIFE DATES: From: To: 2008-09-02 to 2008-09-23

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

polyethylene glycol

Remarks:

PEG 300 (details available in full study report)

Details on dermal exposure:

TEST SITE
- Area of exposure: the day before treatment the back and flanks were clipped free of hair. Dorsal area application. Note: that the skin was re-shaved on day 8 to facilitate the reading of local reactions.
- % coverage: Approximately 10% of total body surface
- Type of wrap if used: The area of application was covered by a semi-occlusive dressing and wrapped with a piece of elastic adhesive bandage.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): The treated skin and surrounding hair wiped with luke warm water and dried with disposable towl to remove any residual test item
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg
- Concentration (if solution): See below.
- Constant volume or concentration used: 4 mL volume ; at a dose level of 2000 mg/kg bw test item.

Duration of exposure:

24 hours

Doses:

2000 mg/kg

No. of animals per sex per dose:

5 per sex per dose (5 male/5 female)

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations and mortality checks were conducted at approximately 0.5, 1, 3, and 5 hours and subsequently twice daily for days 2 to 15. Local effects were examined once daily days 2 to 15 after the completion of the 24-hour exposure period. Full details on the scoring and criteria (appears consistent with Draize for Erythema) are given in the full study report. Individual bodyweights were recorded prior to application of the test item on Day 1 and on Days 8 and 15.
- Necropsy of survivors performed: yes

Statistics:

No statistical analyses were performed.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality was observed.

Clinical signs:

other: - Clinical observations: No signs of systemic toxicity were noted during the observation period. - Dermal reactions: All indicated slight (score = 1) to moderate (score =2) erythema from day 2 to day 6. The sites were re-shaved on day 8 after which one in

Gross pathology:

No abnormalities were noted at necropsy.

Any other information on results incl. tables

Applicant assessment indicates: within local effects the test item caused only mild transient irritation (score = 2) on day 2 which was then slight (score 1) on days 3, 4 and fully reversed by day 7. When the sites were re-shaved on day 8 this led to score = 1 slight irritation and scaling that persisted to the end of the observation period. This was clearly not a test item related effect, as the effects had already reversed on day 7 in all males/females (information provided in the full study report). The OECD TG 404 test guideline for skin irritation specifies that clipping of the fur is done at the start of the test and to attempts are to minimise abrasion of the skin which can interfere with assessment. It appears that the effects post day 8 were the result of a deviation for the reading of local effects which made fully reversed effects re-appear at the treated sites. Expert judgement indicates these were non-test item related effects.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of this study the dermal LD50 was established to exceed 2000 mg/kg bw in male/female Wistar rat. Under the conditions of this study and under the Globally Harmonized Classification System of Classification and Labelling of Chemicals (GHS), the LD50 cut-off value was considered to be greater than 5000 mg/kg body weight.

Executive summary:

The study was performed according to OECD TG 402 and EU Method B.3 Acute Toxicity (Dermal) and in accordance with GLP to assess the acute dermal toxicity of the test substance in the Wistar HanRcc: WIST (SPF) strain rat. A group of ten animals (five males and five females) was given a single, 24 hour, semi-occluded dermal application of the diluted test item in PEG 300 vehicle to intact skin at a dose level of 2000 mg/kg body weight. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy. There was no mortality during the study. There were no signs of system toxicity or abnormalities on necropsy. Animals showed expected gains in body weight. Minimal signs of dermal irritation were noted (score 2) at day 2 and (score 1) days 4 to 5 or 6, which had fully reversed at day 7. The dermal LD50 was established to exceed 2000 mg/kg bw in male/female Wistar HanRcc: WIST (SPF) rat. Under the conditions of this study, and according to the GHS criteria, the LD50 cut-off value was considered to be greater than 5000 mg/kg body weight.