Methyl 2-naphthyl ether

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

Data from experimental study report.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Principles of method if other than guideline:

Acute dermal toxicity study of test chemical was performed in rats.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methyl 2-naphthyl ether

EC Number:

202-213-6

EC Name:

Methyl 2-naphthyl ether

Cas Number:

93-04-9

Molecular formula:

C11H10O

IUPAC Name:

2-methoxynaphthalene

Test material form:

solid

Details on test material:

- Name of test material (as cited in study report): Methyl 2-naphthyl ether
- Molecular formula :C11H10O
- Molecular weight :158.19 g/mol
- Substance type: Organic

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: In-House Bred
- Age at study initiation: no data
- Weight at study initiation: Male: Minimum: 248 g and Maximum: 271 g
(Prior to Treatment) Female: Minimum: 202 g and Maximum: 249 g

- Fasting period before study: no data
- Housing:
Bedding : All cages were provided with corn cobs
Husbandry : The animals were housed individually in polycarbonate cages
Room Sanitation : The experimental room floor and work tops were swept and mopped with disinfectant solution every day.
Cages and water bottle : All the cages and water bottles were changed at least twice every week.
- Diet (e.g. ad libitum): animals were provided conventional laboratory rodent diet ad libitum
- Water (e.g. ad libitum): Aqua guard filtered tap water was provided ad libitum via drinking bottles
- Acclimation period: All animals were acclimatized to the test conditions for 6 days prior to administration of the test item.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): Minimum: 19.80 °C Maximum: 23.20 °C
- Humidity (%): Minimum: 50.60% Maximum: 63.20%
- Air changes (per hr): More than 12 changes per hour
- Photoperiod (hrs dark / hrs light): 12:12

Administration / exposure

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

TEST SITE
- Area of exposure: dorsal area of the trunk
- % coverage: Approx. 10% of body surface area of rat
- Type of wrap if used: porous gauze dressing and non-irritating tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): residual test item was removed by using distilled water
- Time after start of exposure: 24-hour exposure period

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg body weight
- Concentration (if solution): Individual rat was applied with an amount of test item moistened with 0.2 ml distilled water
- Constant volume or concentration used: yes
- For solids, paste formed: yes

VEHICLE
- Amount(s) applied (volume or weight with unit): 0.2ml

Duration of exposure:

24 hrs

Doses:

2000 mg/kg body weight

No. of animals per sex per dose:

Five male and five female wistar rats

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: individual animals were frequently observed at 1, 2, 3 and 4 hours post dosing on day 0 (day of dosing). Subsequently, all animals were observed once a day during the 14 day observation period
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology were observed

Statistics:

No data available

Results and discussion

Preliminary study:

No data available

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

other: No mortality was observed

Mortality:

No mortality was observed at limit dose of 2000 mg/kg body weight of test item during the 14 day observation period

Clinical signs:

other: All the animals were observed with normal clinical signs throughout the experimental period

Gross pathology:

The external and internal gross pathological observation of all terminally sacrificed animals did not show any pathological abnormality

Other findings:

No data available

Any other information on results incl. tables

Table 1: Individual Animal Body Weight (g) andBody Weight Changes(%)

 

Dose:2000 mg/ kg bodyweight                                                                                                         

Animal No.	Sex	Body Weight (gram)			Body Weight Change (%)
		Day 0	Day 7	Day 14	Day 0-7	Day 0-14
1	Male	248	262	282	5.65	13.71
2		270	283	323	4.81	19.63
3		254	277	300	9.06	18.11
4		271	278	304	2.58	12.18
5		263	276	300	4.94	14.07
6	Female	249	239	255	-4.02	2.41
7		214	217	225	1.40	5.14
8		219	228	234	4.11	6.85
9		202	204	204	0.99	0.99
10		203	212	223	4.43	9.85

Table 2: Individual Animal Clinical Signs and Symptoms

 

Dose:2000 mg/kg body weight

Animal No.	Sex	Hour(s) - Day 0				Day
		1	2	3	4	1	2	3	4	5	6	7
1	Male	1	1	1	1	1	1	1	1	1	1	1
2		1	1	1	1	1	1	1	1	1	1	1
3		1	1	1	1	1	1	1	1	1	1	1
4		1	1	1	1	1	1	1	1	1	1	1
5		1	1	1	1	1	1	1	1	1	1	1
6	Female	1	1	1	1	1	1	1	1	1	1	1
7		1	1	1	1	1	1	1	1	1	1	1
8		1	1	1	1	1	1	1	1	1	1	1
9		1	1	1	1	1	1	1	1	1	1	1
10		1	1	1	1	1	1	1	1	1	1	1

 

Animal No.	Sex	Day
		8	9	10	11	12	13	14
1	Male	1	1	1	1	1	1	1
2		1	1	1	1	1	1	1
3		1	1	1	1	1	1	1
4		1	1	1	1	1	1	1
5		1	1	1	1	1	1	1
6	Female	1	1	1	1	1	1	1
7		1	1	1	1	1	1	1
8		1	1	1	1	1	1	1
9		1	1	1	1	1	1	1
10		1	1	1	1	1	1	1

Key: 1 = Normal

Table 3: Individual Animal Mortality Record

 

Dose:2000 mg/kg body weight

Animal No.	Sex	Days of Observation (0 to 14)
		Morning Observations	Evening Observations
1	Male	No mortality and morbidity	No mortality and morbidity
2		No mortality and morbidity	No mortality and morbidity
3		No mortality and morbidity	No mortality and morbidity
4		No mortality and morbidity	No mortality and morbidity
5		No mortality and morbidity	No mortality and morbidity
6	Female	No mortality and morbidity	No mortality and morbidity
7		No mortality and morbidity	No mortality and morbidity
8		No mortality and morbidity	No mortality and morbidity
9		No mortality and morbidity	No mortality and morbidity
10		No mortality and morbidity	No mortality and morbidity

Table 4:Summaryof Animal Body Weight (g) and Body Weight Changes (%)

 

Dose:2000 mg/kg body weight

Sex		Body Weight (gram)			Body Weight Changes (%)
		Day 0	Day 7	Day 14	Day 0-7	Day 0-14
Male	Mean	261.20	275.20	301.80	5.41	15.54
	SD	10.03	7.85	14.60	2.34	3.17
	n	5	5	5	5	5
Female	Mean	217.40	220.00	228.20	1.38	5.05
	SD	19.09	13.73	18.54	3.39	3.53
	n	5	5	5	5	5

Keys:SD= Standard deviation, n = Number of animals

Table 5: GrossNecropsyObservation

 

 Dose:2000 mg/kg body weight                                               Mode of Death:Terminal Sacrifice

Animal No.	Sex	Gross Observation
		External	Internal
1	Male	No abnormalities detected	No abnormalities detected
2		No abnormalities detected	No abnormalities detected
3		No abnormalities detected	No abnormalities detected
4		No abnormalities detected	No abnormalities detected
5		No abnormalities detected	No abnormalities detected
6	Female	No abnormalities detected	No abnormalities detected
7		No abnormalities detected	No abnormalities detected
8		No abnormalities detected	No abnormalities detected
9		No abnormalities detected	No abnormalities detected
10		No abnormalities detected	No abnormalities detected

Applicant's summary and conclusion

Interpretation of results:

other: not classified

Conclusions:

The LD50 value was considered to be >2000 mg/kg bw. When male and female wistar rats were treated with test chemical by dermal application .

Executive summary:

Acute dermal toxicity study of test chemical in Rats was performed as per OECD No. 402. Five male and five female healthy young adult rats were randomly selected and used for conducting acute dermal toxicity study. Rats free from injury and irritation of skin were selected for the study. Twenty four hours prior to dermal application of test item, approximately 10% of body surface area of each rat was clipped. A limit dose of 2000 mg/ kg body weight of test item moistened with 0.2 ml distilled water was applied by single dermal application and observed for 14 days after treatment.

On test day 0, an amount of test item moistened with 0.2 ml distilled water was applied directly on the intact skin of clipped area of rats; the porous gauze dressing was put on to the intact skin of clipped area.This porous gauze dressing was covered with a non-irritating tape.After the 24-hour application period, the dressings were removed and the skin was gently wiped with distilled water.The skin reactions were assessed. All the animals were observed for mortality, clinical signs, body weight and gross pathology. No mortality were observed in any animal, normal clinical signs were observed. Mean body weight of male and female was observed with increase on day 7 and 14, as compared to day 0. No pathological abnormality were observed. Thus the LD50 value was considered to be >2000 mg/kg bw. When male and female wistar rats were treated with test chemical by dermal application .