2-(2-naphthyloxy)ethanol

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 January to 21 February 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Compliant with current guidelines and GLP compliant

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

GLP compliance:

yes

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-(2-naphthyloxy)ethanol

EC Number:

202-228-8

EC Name:

2-(2-naphthyloxy)ethanol

Cas Number:

93-20-9

Molecular formula:

C12H12O2

IUPAC Name:

2-(2-naphthyloxy)ethanol

Details on test material:

- Name of test material (as cited in study report): 2 (2 naphthoxy)ethanol
- Physical state: Light tan-coloured waxy solid
- Analytical purity: >98.5%
- Lot/batch No.: E00173-186
- Expiration date of the lot/batch: 31 July 2013
- Storage condition of test material: Ambient temperature, in the dark

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River UK, Margate
- Age at study initiation: Approximately 8 to 10 weeks old
- Weight at study initiation: 198 and 230 g (males) and 213 and 232 g (females)
- Fasting period before study: No
- Housing: Singly housed
- Diet (e.g. ad libitum): Ad libitum
- Water (e.g. ad libitum): Ad libitum
- Acclimation period: At least 7 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): Approximately 22°C on each day
- Humidity (%): approximately 32% to 49%.
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12 h light/dark cycle

IN-LIFE DATES: From: To: 31 January to 21 February 2012

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: ~38 cm2 (males) and ~25 cm2 (females)
- % coverage: ~12% (males), ~8% (females)
- Type of wrap if used: Micropore and Sleek tape

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Sterile water
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 426 mg (males), 444 mg (females)
- Concentration (if solution): NA
- For solids, paste formed: no

Duration of exposure:

24 h

Doses:

2000 mg/kg

No. of animals per sex per dose:

5

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: 5 times on the day of dosing and once daily from Day 2 until Day 15
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weights

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

There were no deaths among animals treated with 2 (2 naphthoxy)ethanol at 2000 mg/kg.

Clinical signs:

other: There were no signs of systemic toxicity in any animal at any observation timepoint. Clinical signs were restricted to staining to test site, which was seen in 2 males on Day 2, and test item residues at the test site, which was seen in 4 females on Day 2

Gross pathology:

There were no abnormal findings noted at necropsy.

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under the conditions of the study, the median lethal dermal dosage (LD50) for 2 (2 naphthoxy)ethanol in Sprague-Dawley rats was estimated to be greater than 2000 mg/kg.
This study is considered to be relevant, reliable and adequate for risk assessment and for classification purposes.

Executive summary:

The objective of this study was to assess the adverse effects which can follow within a short period of time after a single dermal administration of 2-(2-naphthoxy)ethanol to rats.

The test item was administered to a single group of 5 male and 5 female Sprague-Dawley rats. The study design was as follows:

Text Table1
Experimental Design

Dose Level (mg/kg)	Animal Numbers
	Males	Females
2000	1 to 5	6 to 10

 

The test item was administered, as supplied, onto the moistened dorsal trunk under a gauze patch, also moistened, which was covered with semi-occlusive tape, then secured with occlusive tape (ie the site was fully occluded). The dressings remained in place for 24 h. The dose was calculated on the basis of the body weights of the animals on the day of dosing. Animals were observed for signs of reaction to treatment 5 times on the day of dosing and once daily from Day 2 until the end of the observation period on Day 15. Body weights were recorded weekly and all animals were subjected to a necropsy examination.

The following parameters and end points were evaluated in this study: clinical signs, body weights, body weight changes, and gross necropsy findings.

There were no unscheduled deaths during the observation period.

There were no systemic signs of toxicity noted in any animal at any observation timepoint and local findings at the dosing site were restricted to staining or test item residues at the test site, which were seen in 6 animals on Day 2 only.

Body weight gain was considered to be acceptable for rats of this age and strain. No abnormal findings were noted at necropsy.

Under the conditions of the study, the median lethal dermal dosage (LD₅₀) for 2-(2-naphthoxy)ethanol in Sprague-Dawley rats was estimated to be greater than 2000 mg/kg.