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Diss Factsheets

Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
data from handbook or collection of data
Justification for type of information:
Data is from peer reviewed journals

Data source

Reference
Reference Type:
publication
Title:
Contact-Group Sensitization to Triphenylmethane Dyes
Author:
Novák M et.al
Year:
1969
Bibliographic source:
Arch Dermatol, 1969

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: as mentioned below
Principles of method if other than guideline:
Patch tests were performed to evaluate the degree of allergic reactions caused by the test chemical
GLP compliance:
not specified
Type of study:
patch test
Justification for non-LLNA method:
not specified

Test material

Constituent 1
Chemical structure
Reference substance name:
[4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride
EC Number:
209-322-8
EC Name:
[4-[α-[4-(dimethylamino)phenyl]benzylidene]cyclohexa-2,5-dien-1-ylidene]dimethylammonium chloride
Cas Number:
569-64-2
Molecular formula:
C23H25N2.Cl
IUPAC Name:
N-(4-{[4-(dimethylamino)phenyl](phenyl)methylene}cyclohexa-2,5-dien-1-ylidene)-N-methylmethanaminium chloride
Test material form:
solid
Details on test material:
- Name of test material (as cited in study report): Malachite Green
- Molecular formula : C23H25N2.Cl
- Molecular weight : 364.9175 g/mol
- Substance type: Organic
- Physical state: SOLID

In vivo test system

Test animals

Species:
other: humans
Strain:
not specified
Sex:
not specified
Details on test animals and environmental conditions:
Source: Clinic of Dermatology, Faculty of Medical Hygiene, Charles University, Prague

Study design: in vivo (non-LLNA)

Induction
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
2% in water
Day(s)/duration:
20 - 24hours
Adequacy of induction:
not specified
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
2% in water
Day(s)/duration:
20 - 24 hourD
Adequacy of challenge:
not specified
No. of animals per dose:
9
Details on study design:
Other: The patch tests were put on for 20 to 24 hours and they were evaluated for six to seven days. Since the skin is colored by the tested dye, it was not possible to evaluate the erythematous reaction. For this reason evaluation was recorded as follows:
Itching = ±
Isolated papules = +
Edema, confluent papules, infiltration= + +
Vesicular reaction = + + +
Challenge controls:
No data available
Positive control substance(s):
not specified

Results and discussion

In vivo (non-LLNA)

Results
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
2% in water
No. with + reactions:
6
Total no. in group:
9
Clinical observations:
Edema, confluent papules, infiltration was observed in 2 of 11 volunteers
Remarks on result:
positive indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:
other: sensitizing
Conclusions:
Positive reactions to the test chemical were observed in 6 of the 9 volunteers.
Edema, confluent papules, infiltration was observed in 2 of 9 volunteers
Based on these reactions, the test chemical was considered to be a skin sensitizer in humans.
Executive summary:

Patch tests were performed to evaluate the degree of allergic reactions caused by the test chemical.

The patch tests were put on for 20 - 24 hours on the skin of 11 volunteers. They were evaluated for six to seven days. Since the skin got colored by the test chemical, it was not possible to evaluate the erythematous reaction. For this reason evaluation was recorded as follows:

Itching = ±

Isolated papules = +

Edema, confluent papules, infiltration= + +

Vesicular reaction = + + +

Positive reactions to the test chemical were observed in 6 of the 9 volunteers.

Edema, confluent papules, infiltration was observed in 2 of 9 volunteers.

Based on these reactions, the test chemical was considered to be a skin sensitizer in humans