Reaction mass of 1,2,3,4,5,6,7,8-octahydro-5,5-dimethylnaphthalene-2-carbaldehyde and 1,2,3,4,5,6,7,8-octahydro-8,8-dimethyl-2-naphthaldehyde

Specific investigations: other studies

Administrative data

Endpoint:

phototoxicity

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

A 2 % dilution of the test substance in absolute ethanol was examined for phototoxic properties in six albino rabbits. A 1/128 % solution of 8-methoxypsoralen in absolute alcohol served as positive control. Amounts of 0.1 mL of the test and control dilution were brought into contact with separated skin areas. Subsequently, the treated skin areas were irradiated with UV-light for 60 minutes. 0.1 mL of the test and of the control dilution were brought into contact with separated skin areas, but left unirradiated.

GLP compliance:

yes

Type of method:

in vivo

Endpoint addressed:

skin irritation / corrosion

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 1,2,3,4,5,6,7,8-octahydro-5,5-dimethylnaphthalene-2-carbaldehyde and 1,2,3,4,5,6,7,8-octahydro-8,8-dimethyl-2-naphthaldehyde

EC Number:

916-807-4

Molecular formula:

C13H20O

IUPAC Name:

Reaction mass of 1,2,3,4,5,6,7,8-octahydro-5,5-dimethylnaphthalene-2-carbaldehyde and 1,2,3,4,5,6,7,8-octahydro-8,8-dimethyl-2-naphthaldehyde

Test material form:

liquid

Specific details on test material used for the study:

- Description: clear, transparant liquid

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: ENKI-Konijnenfarm, Someren, the Netherlands
- Weight at study initiation: 2500-3500 g
- Housing: Individually in suspended, galvanized cages, fitted with wire-mesh floor and front
- Diet: Standard laboratory rabbit diet, ad libitum
- Water: Tap water, ad libitum
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18±3
- Humidity (%): 40-70
- Air changes (per hr): ca. 10
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

dermal

Vehicle:

ethanol

Analytical verification of doses or concentrations:

no

No. of animals per sex per dose:

6

Control animals:

no

Details on study design:

One day prior to the start of the experiment, the hair was removed from the back and flanks of the animals using electric clippers in a way as to avoid abrasions. The test was carried out with a 2 % dilution of the test material in absolute ethanol. A 1/128 % solution of 8-methoxypsoralen in absolute ethanol served as a positive control. Amounts of 0.1 mL of the test and control dilution were brought into contact with separated skin areas left of the midline of the back. Subsequently, the treated skin areas were irradiated with UV-light (wavelength about 365 nm) for 60 minutes holding the light source (Philips TL 40 W/ 08) 8 inches from the skin. After removal of the light source 0.1 mL of the test and of the control dilution were brought into contact with separated skin areas right of the midline of the back, in the same sequence as, and opposite to, the treated and irradiated application sites on the left.

Examinations

Examinations:

Resulting skin reactions were evaluated by the method of Draize (J. Pharmacol. Exp. Ther. 82 (1944) 377-90) at 24, 48, 72 and 96 hours after application.

Positive control:

A 1/128 % solution of 8-methoxypsoralen in absolute ethanol

Results and discussion

Details on results:

The 8-MOP solution did not cause any irritation if the treated skin was not UV-irradiated. However, moderate to severe skin irritation occurred in all (six) rabbits after UV-irradiation of the sites treated with the 8-MOP solution. The dermal effects observed generally consisted of well-defined erythema, very slight or slight ischemic necrosis and very slight or slight oedema. The 2 % dilution of the test material caused very slight erythema in one out of six rabbits at the 24 hour time point if the treated skin was not UV-irradiated. Very slight erythema occurred in two out of six rabbits after UV-irradiation of the sites treated with the test substance dilution. The very slight erythema was absent within 48 and 72 hours, respectively. The difference between the numbers of animals showing skin reactions after treatment with the 2 % test item dilution, with and without subsequent UV-irradiation, was considered a chance effect and not of any toxicological significance. On the basis of the present results it is concluded that a 2 % dilution of the test substance in absolute ethanol is not phototoxic for rabbits.