2-[[4-[ethyl(2-hydroxyethyl)amino]phenyl]azo]-6-methoxy-3-methylbenzothiazolium methyl sulphate

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1973-03-08 to 1973-01-22

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1973

Report date:

1973

Materials and methods

Type of sensitisation studied:

skin

Study type:

study with volunteers

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

To determine if the test material is capable of irritating the skin of humans under controlled test conditions, a human Repeated Insult Patch Test was conducted

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-[[4-[ethyl(2-hydroxyethyl)amino]phenyl]azo]-6-methoxy-3-methylbenzothiazolium chloride

EC Number:

248-053-0

EC Name:

2-[[4-[ethyl(2-hydroxyethyl)amino]phenyl]azo]-6-methoxy-3-methylbenzothiazolium chloride

Cas Number:

26850-47-5

Molecular formula:

C19H23ClN4O2S

IUPAC Name:

2-[(E)-{4-[Ethyl(2-hydroxyethyl)amino]phenyl}diazenyl]-6-methoxy-3-methyl-1,3-benzothiazol-3-ium chloride

Details on test material:

Purity: on dyed fabric

Method

Type of population:

general

Ethical approval:

confirmed and informed consent free of coercion received

Subjects:

- Number of subjects exposed: 200
- Sex: male/female
- Age: not specified
- Race: not specified
- Demographic information: local population

Clinical history:

- General well-being.
- Absence of any skin disease which might be confused with skin reactions from the test material.

Controls:

no

Route of administration:

dermal

Details on study design:

PROCEDURE:
A group of 200 individuals who qualified were selected from a local population. All of these individuals volunteered to participate in this evaluation. The
criteria for qualifying were: General well-being, absence of any skin disease which might be confused with skin reactions from the test material, willingness to cooperate, dependability and intelligence in following directions and reading, understanding, and signing an informed-consent contract (In the case of minors, parental consent was obtained.) The test materials were applied under occlusion for a series of effective contact periods of two days' duration, i. e . Monday to Wednesday, and Wednesday to Friday of each week for four weeks. On Mondays, the test materials were applied. On Wednesdays, the patches were removed, the contact sites examined, and the test materials re-applied for another fortyeight hour period. On Fridays, the covers were removed and the contact sites were again examined and graded. The contact sites were then rested until the following Monday. A mixture of the group of four materials was applied to a single predesignated contact site which was reserved for this specific group throughout the test. On each application day, 4% aqueous solutions were freshly made. Fifty mL of the solutions of each of the four test materials comprising each group were then mixed together and one mL was pipetted off to saturate a lintine disc,
1.25 inch in diameter. One such disc was placed intimately in contact with the contact site on each participant and covered with a water-impermeable sheet of plastic (1.5 inch by 1.5 inch). The plastic was then affixed to the skin with Blenderm tape applied in such a manner as to seal the edges and maintain the integrity of the micro-climate under the patch. On the second Monday following the removal of the last series of applications, each contact site was challenged with its corresponding composite of test
materials. The covers were removed on Wednesday, thereby effecting a challenge contact period of forty-eight hours' duration. The contact sites were examined for visible changes which, if present, were graded and recorded. Sites were re-examined twenty-four and forty-eight hours later for delayed reactions. Composites which elicited reactions during the test were separated into individual
components for re-challenge on reacting individuals. Results of these re-challenge applications are appended. At all reading periods, it was found useful to wash the sites in order to remove the dyestuffs obscuring the underlying skin. Mild, gentle sponging
with warm water was found to be satisfactory.

EXAMINATIONS
- Grading/Scoring system:
0 = No reactions
1+ = Slight erythema
2+ = Marked erythema
3+ = Marked erythema, edema, with or without a few vesicles
4+ = Marked erythema, edema, with vesicles and oozing.

Statistical analysis:
- Other: At all reading periods, it was found useful to wash the sites in order to remove the dyestuffs obscuring the underlying skin. Mild, gentle sponging with warm water was found to be satisfactory.

Results and discussion

Results of examinations:

Visible skin changes signifying reaction to injury were observed in 1 out of 200 subjects during the series of application or following the challenge application. On re-challenge, the component found to be responsible was the not the source substance , but one of the other tested test items.

Any other information on results incl. tables

Table 1: Summary of Reaction Grades

Number of Exposure	Number of Reactions in Grades Indicated
	0	1+	2+	3+	4+	NP
1	200	0	0	0	0	0
2	200	0	0	0	0	0
3	200	0	0	0	0	0
4	200	0	0	0	0	0
5	200	0	0	0	0	0
6	199	0	0	0	1	0
7	199	0	0	0	0	1
8	199	0	0	0	0	1
9	199	0	0	0	0	1
10	199	0	0	0	0	1
11	199	0	0	0	0	1
12	199	0	0	0	0	1
13	199	0	0	0	0	1
14	199	0	0	0	0	1
15	199	0	0	0	0	1

Applicant's summary and conclusion

Conclusions:

The test item is not a skin sensitiser in human patch tests when applied at 1% in aqueous solution.

Executive summary:

In a Human Repeated Insult Patch Test, 200 volunteers were dermally exposed to the test item for four weeks at a concentration of 1 % in aqueous solution together with three other materials (composite material). The skin was challenged two weeks after the last induction application to determine any skin sensitizing potential of the test item. One person showed visible skin changes at the sixth exposure time, which was later confirmed to be caused by one of the other test material of the composite material by re-challenging with the individual components of the composite material.