5H-Cyclopenta[h]quinazoline, 6,7,8,9-tetrahydro-7,7,8,9,9-pentamethyl-

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 July 2013 and 21 August 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

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 (incl. QA statement)

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

1

Reference substance name:

(8S)-7,7,8,9,9-pentamethyl-5H,6H,7H,8H,9H-cyclopenta[h]quinazoline

EC Number:

801-093-8

Cas Number:

1315251-11-6

Molecular formula:

C16H22N2

IUPAC Name:

(8S)-7,7,8,9,9-pentamethyl-5H,6H,7H,8H,9H-cyclopenta[h]quinazoline

Test material form:

solid

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Oxon, UK.
- Age at study initiation: Eight to twelve weeks of age.
- Weight at study initiation: at least 200 g The weight variation did not exceed ±20% of the mean weight for each sex.
- Fasting period before study: No data
- Housing: The animals were housed individually during the 24-Hour exposure period and in groups of five, by sex, for the remainder of the study.
- Diet: Mains drinking water ad libitum.
- Water: 2014C Teklad Global Rodent diet ad libitum.
- Acclimation period: At least five days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): The temperature was set to achieve limits of 19 to 25 °C
- Humidity (%): The relative humidity was set to achieve limits of 30 to 70 %
- Air changes (per hr): At least fifteen changes per hour.
- Photoperiod (hrs dark / hrs light): Lighting was controlled by a time switch to give twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

arachis oil

Details on dermal exposure:

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 for the 24-Hour exposure period. 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. 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 ½, 1, 2 and 4 hours after dosing and subsequently once daily for fourteen days. 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 following 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

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

Preliminary test: 1/sex/dose
Main test: 4/sex/dose

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: The animals were observed at 0.5, 1, 2, 4 hours after dosing and then once daily for 14 days. Individual body weights were recorded prior to application of the test item on day 0 and on days 7 and 14.
- Necropsy of survivors performed: Yes
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.
- Other examinations performed: Death and overt signs of toxicity.

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:

other: No deaths or signs of clinical toxicity

Mortality:

There were no deaths.

Clinical signs:

other: No signs of systemic toxicity were noted during the observation period.

Gross pathology:

Very slight erythema was noted at the test sites of three females. Small superficial scattered scabs and scab lifting to reveal glossy skin were also noted at the test site of one female. There were no signs of dermal irritation noted at the test sites of the remaining animals.
No abnormalities were noted at necropsy.

Any other information on results incl. tables

Individual Dermal Reactions - Females

Dose level (mg/kg)	Animal No. & sex	Observation	Effects noted after initial exposure (Days)
			1	2	3	4	5	6	7	8	9	10	11	12	13	14
2000	2-0 Female	Erythema	1	1	0	0	0	0	1	1	0	0	0	0	0	0
		Oedema	0	0	0	0	0	0	0	0	0	0	0	0	0	0
		Other	0	0	0	0	0	0	SsSg	SsSg	Ss	Ss	Ss	Ss	Ss	Ss
	4-0 Female	Erythema	0	0	0	1	1	0	0	0	0	0	0	0	0	0
		Oedema	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	1	1	0	0	0	0	0	0	0	0	0
		Oedema	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
		Oedema	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
		Oedema	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

Individual Dermal Reactions - Males

Dose level (mg/kg)	Animal No. & sex	Observation	Effects noted after initial 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
		Oedema	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
		Oedema	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
		Oedema	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
		Oedema	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
		Oedema	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, Ss = Small superficial scattered scabs, Sg = Scab lifting to reveal glossy skin

Individual Body Weights and Body Weight Changes

Dose Level (mg/kg)	Animal No. and Sex	Body weight (g) at Day			Body weight (g) During Week
		0	7	14	1	2
2000	1-0 Male	283	291	314	8	23
	3-0 Male	291	296	311	5	15
	3-1 Male	287	291	310	4	19
	3-2 Male	289	294	317	5	23
	3-3 Male	280	292	311	12	19
	2-0 Female	225	230	238	5	8
	4-1 Female	221	227	238	6	11
	4-2 Female	216	224	227	8	3
	4-3 Female	218	229	242	11	16
	4-4 Female	231	232	240	1	8

Individual Necropsy Findings

Dose Level (mg/kg)	Animal No. and Sex	Time of Death	Microscopic 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
	4-1 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
	4-4 Female	Killed Day 14	No abnormalities detected

Applicant's summary and conclusion

Interpretation of results:

other:

Remarks:

Not harmful in accordance with EU CLP (EC no 1272/2008 and its amendments)

Conclusions:

The acute dermal median lethal dose (LD50) of the substance in the Wistar strain rat was found to be greater than 2000 mg/kg body weight.

Executive summary:

The study was performed to assess the acute dermal toxicity of the substance in the Wistar strain rat. Initially, two animals (one male and one female) were given a single, 24 hour, semi-occluded dermal application of the substance to intact skin at a dose level of 2000 mg/kg body weight. Based on the results of the initial test, a further group of eight animals (four males and four females) was similarly treated. Clinical signs and body weight development were monitored during the study. All animals were subjected to gross necropsy.

Results showed that there were no deaths. There were no signs of systemic toxicity. Very slight erythema was noted at the test sites of three females. Small superficial scattered scabs and scab lifting to reveal glossy skin were also noted at the test site of one female. There were no signs of dermal irritation noted at the test sites of the remaining animals. All animals showed expected gains in body weight. No abnormalities were noted at necropsy.

In conclusion, the acute dermal median lethal dose (LD50) of the substance in the Wistar strain rat was found to be greater than 2000 mg/kg body weight.