3-(6,6-dimethylbicyclo[3.1.1]hept-2-en-2-yl)-2,2-dimethylpropanenitrile

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental start date: 31 March 2016 - Experimental completion date: 21 April 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

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

Limit test:

yes

Test material

Test material information

1

Reference substance name:

3-(6,6-dimethylbicyclo[3.1.1]hept-2-en-2-yl)-2,2-dimethylpropanenitrile

EC Number:

814-345-7

Cas Number:

2003244-43-5

Molecular formula:

C14H21N

IUPAC Name:

3-(6,6-dimethylbicyclo[3.1.1]hept-2-en-2-yl)-2,2-dimethylpropanenitrile

Details on test material:

- Name of test material (as cited in study report): ES421 Pinyl Nitrile- Molecular weight (if other than submission substance): 203 g/mol- Physical state: Crystallized white powder- Analytical purity: 98.08% (per Certificate of Analysis)- Composition of test material, percentage of components: 2-Norpinene-2-propionitrile, alpha, alpha,6,6-tetramethyl- Purity test date: 08 February 2016- Lot/batch No.: SM15077102- Storage condition of test material: 2-8°C, protected from light

Specific details on test material used for the study:

Physical state/Appearance: white solid
Storage Conditions: approximately 4 °C in the dark

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

On receipt the animals were randomly allocated to cages. The females were nulliparous and non pregnant. After an acclimatization period of at least 5 days the animals were selected at random and given a number unique within the study by indelible ink marking on the tail and a number written on a cage card. At the start of the study the animals weighed at least 200 g, and were 8 to 12 weeks of age. The weight variation did not exceed ±20% of the mean weight for each sex.
The animals were housed in suspended solid floor polypropylene cages furnished with woodflakes. The initial two animals were housed individually throughout the study. The further group of eight animals (four male and four female) were housed individually during the 24 Hour exposure period and in groups of four, by sex, for the remainder of the study. Free access to mains drinking water and food was allowed throughout the study. The diet, drinking water and bedding were routinely analyzed and were considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
The temperature and relative humidity were set to achieve limits of 19 to 25 C and 30 to 70% respectively. The rate of air exchange was at least fifteen changes per hour and the lighting was controlled by a time switch to give 12 hours continuous light and 12 hours darkness.
The animals were provided with environmental enrichment items which were considered not to contain any contaminant of a level that might have affected the purpose or integrity of the study.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

arachis oil

Details on dermal exposure:

The appropriate amount of test item, moistened with arachis oil BP, was applied as evenly as possible to an area of shorn skin (approximately 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 throughout the study. Shortly after dosing the dressings were examined to ensure that they were securely in place.

Duration of exposure:

24 Hour contact period

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

five males and five females

Control animals:

no

Details on study design:

On the day before treatment the back and flanks of each animal were clipped free of hair.
In the absence of data suggesting the test item was toxic, one male and one female rat were initially treated with the test item at a dose level of 2000 mg/kg.
The appropriate amount of test item, moistened with arachis oil BP, was applied as evenly as possible to an area of shorn skin (approximately 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 throughout the study. Shortly after dosing the dressings were examined to ensure that they were securely in place.
After the 24 Hour contact period the bandage was carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with arachis oil BP to remove any residual test item.
As no mortalities were noted a further group of animals (four males and four females) was similarly treated with the test item at a dose level of 2000 mg/kg body weight to give a total of five males and five females. The animals were caged individually for the 24 Hour exposure period. After the 24 Hour contact period the bandages were carefully removed and the treated skin and surrounding hair wiped with cotton wool moistened with arachis oil BP to remove any residual test item. These animals were returned to group housing for the remainder of the test period.
The animals were observed for deaths or overt signs of toxicity 30 minutes, 1, 2 and 4 hours after dosing and subsequently once daily for 14 days.
Any other skin reactions, if present were also recorded.
Individual body weights were recorded prior to application of the test item on Day 0 and on Days 7 and 14.
At the end of the study the animals were killed by cervical dislocation. All animals were subjected to gross necropsy. 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.

Results and discussion

Preliminary study:

As no mortalities were noted a further group of animals (four males and four females) was similarly treated with the test item at a dose level of 2000 mg/kg body weight to give a total of five males and five females.

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths (see Table 1).

Clinical signs:

No signs of systemic toxicity were noted during the observation period (see Table 1). There were no signs of dermal irritation (see Tables 2 and 3).

Body weight:

Animals showed expected gains in body weight, except for two females which showed body weight loss during the first week with expected gain in body weight during the second week (see Table 4).

Gross pathology:

No abnormalities were noted at necropsy (see Table 5).

Any other information on results incl. tables

Table 1:      Individual Clinical Observations and Mortality Data

Dose Level mg/kg	Animal Number and Sex	Effects Noted After Dosing (Hours)				Effects Noted During Period After Dosing (Days)
		½	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	1-0 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Male	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	2-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-0 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-1 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-2 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-3 Female	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0=  No signs of systemic toxicity

Table 2:      Individual Dermal Reactions - Males

Dose Level mg/kg	Animal Number and Sex	Observation	Effects Noted After Initiation of Exposure (Days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	1-0 Male	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-0 Male	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-1 Male	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-2 Male	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	3-3 Male	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0= No reactions

Table 3:      Individual Dermal Reactions - Females

Dose Level mg/kg	Animal Number and Sex	Observation	Effects Noted After Initiation of Exposure (Days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	2-0 Female	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-0 Female	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-1 Female	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-2 Female	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0
	4-3 Female	Erythema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Edema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	0	0	0	0	0	0	0	0

0= No reactions

Table 4:      Individual Body Weights and Body Weight Changes

Dose Level mg/kg	Animal Number and Sex	Body Weight (g) at Day			Body Weight Change (g) During Week
		0	7	14	1	2
2000	1-0 Male	250	274	312	24	38
	3-0 Male	280	301	320	21	19
	3-1 Male	294	316	331	22	15
	3-2 Male	257	273	290	16	17
	3-3 Male	256	266	277	10	11
	2-0 Female	210	216	220	6	4
	4-0 Female	222	224	230	2	6
	4-1 Female	224	222	226	-2	4
	4-2 Female	216	212	216	-4	4
	4-3 Female	208	217	224	9	7

Table 5:      Individual Necropsy Findings

Dose Level mg/kg	Animal Number and Sex	Time of Death	Macroscopic Observations
2000	1-0 Male	Killed Day 14	No abnormalities detected
	3-0 Male	Killed Day 14	No abnormalities detected
	3-1 Male	Killed Day 14	No abnormalities detected
	3-2 Male	Killed Day 14	No abnormalities detected
	3-3 Male	Killed Day 14	No abnormalities detected
	2-0 Female	Killed Day 14	No abnormalities detected
	4-0 Female	Killed Day 14	No abnormalities detected
	4-1 Female	Killed Day 14	No abnormalities detected
	4-2 Female	Killed Day 14	No abnormalities detected
	4-3 Female	Killed Day 14	No abnormalities detected

 

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The acute dermal median lethal dose (LD50) of the test item in the Wistar strain rat was found to be greater than 2000 mg/kg body weight.
The test item does not meet the criteria for classification according to the Globally Harmonized System of Classification and Labelling of Chemicals.

Executive summary:

The acute dermal median lethal dose (LD₅₀) of the test item in the Wistar strain rat was found to be greater than 2000 mg/kg body weight according to OECD Test Guideline 402 using the acute dermal toxicity method.