2-chloroethanol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed pre-GLP and according to methods similar to OECD404.

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

publication

Title:

Tissue Reactions to 2-Chloroethanol in Rabbits

Author:

Guess, W.L.

Year:

1970

Bibliographic source:

Toxicol. Appl. Pharamcol., 16, pp 382-390,

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Principles of method if other than guideline:

Method: Draize Test (1944)
- skin was exposed to 0.2ml under occlusion and for 2 hours
- only the average score for 6 animals per concetration was shown, not the animal individual data.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-chloroethanol

EC Number:

203-459-7

EC Name:

2-chloroethanol

Cas Number:

107-07-3

Molecular formula:

C2H5ClO

IUPAC Name:

2-chloroethan-1-ol

Details on test material:

Anhydrous 2-chloroethanol was obtained from J. T. Baker Company.
Confirmation of purity was further accomplished by infrared analysis and index of refraction. These tests failed, however, to reveal traces of HCl
which altered the pH of the solutions of 2-chloroethanol in normal saline. This HCl was detected by silver nitrate test solution; on titration with 0.1 N NaOH solution, the hydrogen ion concentration was found to be 0.011 mole/liter. The HCl present in the 2- chloroethanol probably originates from hydrolysis of the compound in the presence of moisture. It was felt that chloroacetic acid was not the source of the acidic reaction since
the conditions necessary for the oxidation of the alcohol to the acid were not present.

Test animals

Species:

rabbit

Strain:

New Zealand White

Test system

Type of coverage:

occlusive

Preparation of test site:

other: normal and abraded

Vehicle:

physiological saline

Controls:

no

Amount / concentration applied:

0.2 ml

Duration of treatment / exposure:

2 hours

Observation period:

72 hours

Number of animals:

6

Details on study design:

For the skin irritation study, the method of Draize et al. (1944) was used with the following deviations: It was found impractical in view of the large numbers of animals in this study to use the rubber sleeve covering described by Draize. Instead, the animals were anesthetized with pentobarbital iv, the necessary incisions were made, and glass wells (1 cm id, x3 mm) were sealed to the skin over the desired areas of application with Dow-Corning silicone grease. The test liquids were added to the glass wells in a volume of 0.2 ml per well and sealed with a round microscope coverslip. These were allowed to remain on the site for 2 hours, thereby maintaining the test liquids at the site for a standard time and in known concentration. The sites of exposure were scored for degree of erythema and edema, 24, 48, and 72 hours after exposure.

Results and discussion

In vivo

Irritant / corrosive response data:

2-chloroathanol caused only barely perceptible reaction on normal and abraded skin under the conditions of this test. In this regard, only the pure material caused even a transient reaction to intact skin, see table 1.

Any other information on results incl. tables

Table 1. Skin reactions

		Rabbit skin
		Intact		Abraded
Compound	Dilution	24 hr	72 hr	24 hr	72 hr	Combined average 72 hr score
2-chloroethanol	Undiluted	0.6	0	1.0	1.0	0.5
	1:5	0	0	0.6	0.3	0.15
	1:10	0	0	0	0.3	0.15
	1:100	0	0	0.3	0.3	0.15
Saline control	-	0	0	0	0	0
Ethanol	95%	0	0	0.3	0	0
	1:10	0	0	0.3	0	0

-Score (each score represents an average of 6 rabbits used for each)

1, barely perceptibl erythema;

2, well-defined erythema;

3, moderate erythema;

4, severe (beet red) erythema.

 

No oedema observed

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

2-chloroethanol caused only barely perceptible reaction on normal and abraded skin under the conditions of this test. In this regard, only the pure material caused even a transient reaction to intact skin. The maximun average score is 0.6 for the undiluted compound after 24 hours. This was fully reversible within 72 hours. No further effects observed.

Executive summary:

This paper reports on the effect of pure 2-chloroethanol, and various dilutions of this material, on several of the tissue types with which a tracheotomy tube might come into contact in a patient. It was found that pure 2-chloroethanol is quite destructive to most of the tissues, including ophthalmic, mucosal, muscular, and subcutaneous tissues; however, on dilution, the toxicity potential decreased sharply. Dilutions of 1:10 were still toxic, but in most cases, dilutions of 1:100 were practically innocuous. A cell culture evaluation correlated almost perfectly with in vivo techniques.