3,7-dimethylocta-1,6-diene

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From February 01, 1980 to March 07, 1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study performed similarly to OECD guideline 402 with minor deviations: no data about purity, source, no certificate of analysis of the test substance and no data on environmental conditions (humidity, air changes and photoperiod)

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

yes

Remarks:

no data on purity, source, no certificate of analysis of the test substance and no data on environmental conditions

Principles of method if other than guideline:

Not applicable

GLP compliance:

not specified

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,7-dimethylocta-1,6-diene

EC Number:

219-433-3

EC Name:

3,7-dimethylocta-1,6-diene

Cas Number:

2436-90-0

Molecular formula:

C10H18

IUPAC Name:

3,7-dimethylocta-1,6-diene

Details on test material:

- Name of test material (as cited in study report): 79-16229, Dihydromyrcene, 0-67-4945, 79-4-16229
- Physical state: Clear liquid
- Specific gravity: 0.74
- Sample received: December 27, 1979

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Perfection Breeders Nicholas Helf
- Age at study initiation: 8 weeks
- Weight at study initiation: 2.1-2.8 kg
- Housing: Animals were housed two/cage in suspended wire mesh cages
- Diet: Fresh Purina rabbit chow; ad libitum
- Water: Ad libitum
- Acclimation period: One week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-21 °C

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: Abdomen
- % coverage: ca. 10% of body surface area
- Type of wrap if used: Test material was applied directly beneath gauze patches to the abraded skin, secured in position with surgical adhesive tape and then covered with impervious material.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Test sites were not washed but wiped free of excess test material
- Time after start of exposure: 24 hours

TEST MATERIAL
- Amount(s) applied (volume with unit): 14.2-18.9 cm3
- Constant volume or concentration used: No

Duration of exposure:

24 hours

Doses:

5000 mg/kg bw

No. of animals per sex per dose:

Four males and six females

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observed daily for signs of toxicity, pharmacological effects and mortality; body weights were recorded pretest and in the survivors on Day 14
- Necropsy of survivors performed: Yes; surviving animals were killed and examined grossly
- Other examinations performed: Dermal reaction were scored at 24 hours using Draize scoring system

Statistics:

No data

Results and discussion

Preliminary study:

Not applicable

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

1/10 animal died on Day 11

Clinical signs:

other: - Lethargy and diarrhea were major signs of toxicity noted in all animals. - Adipsia, anorexia, ptosis, yellow nasal discharge, mucus in stool or post dose vocalisation were also noted in one or two animals.

Gross pathology:

- Necropsy of animal which died on Day 11 revealed heavily congested lungs and moderately dilated heart
- Necropsy of the surviving animals revealed no abnormalities except slightly ulcerated or slight to moderately scaly skin

Other findings:

- Local irritation reactions at application site: Erythema was nonexistent to slight while edema was slight-moderate on Day 1

Any other information on results incl. tables

Table 1: Individual dermal reactions

 

Rabbit number	Dose volume (cc)	Day 1 dermal reactions		% Remaining
		Erythema	Edema
1	18.9	2	3	85
2#	14.9	2	2	50
3	15.5	0	2	80
4#	15.5	0	3	85
5	14.2	1	3	85
6#	18.9	1	3	80
7	15.5	1	3	85
8#	14.9	0	3	80
9	14.2	0	2	80
10#	16.2	0	2	75

#: abraded

%remaining: the amount of material remaining on the skin, gauze and occlusive binding at 24 hours after the occlusive binding was removed.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The acute dermal LD50 for Dimethyloctadiene is higher than 5000 mg/kg bw in rabbits and therefore it is not classified according to the criteria of the Annex VI of Directive 67/548/EEC and according to the CLP Regulation (EC) n° 1272/2008.

Executive summary:

In an acute dermal toxicity study (limit test) performed similarly to OECD guideline 402, a group of four male and six female New Zealand White rabbits received a single dermal dose of Dimethyloctadiene (in the report the synonym Dihydromyrcene was used) at 5000 mg/kg bw at dose volume of 14.2-18.9 cm3. Dimethyloctadiene was applied to abraded/non-abraded skin in the abdomen representing 10% of the total body surface area using an occlusive patch kept in contact with the skin for 24 hours. Parameters evaluated included survival, clinical observations, body weight gain and necropsy findings in all animals after a 14 days observation period.

 

Only 1/10 animal died on Day 11. Major signs of toxicity noted in all animals were lethargy and diarrhea. Adipsia, anorexia, ptosis, yellow nasal discharge, mucus in stool or post dose vocalisation were also noted in one or two animals. Necropsy of animal which died on Day 11 revealed heavily congested lungs and moderately dilated heart. Necropsy of the surviving animals revealed no abnormalities except slightly ulcerated or slight to moderately scaly skin. The acute dermal LD50 was greater than 5000 mg/kg bw. Adverse dermal reactions noted on Day 1 were nonexistent to slight erythema and slight to moderate ededma.

 

Under the test conditions, Dimethyloctadiene is not classified according to the criteria of the Annex VI of Directive 67/548/EEC and according to the CLP Regulation (EC) n° 1272/2008.