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Diss Factsheets

Administrative data

Description of key information

Based on the data presented, the test substance Disperse Violet 93:1 (Br) seems to react as a skin sensitiser at concentration of ≥ 25% if the animals were pre-treated with an adjuvant. Without adjuvant, concentrations of up to 12.5% did not cause skin sensitising effects.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
March/April 1987
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
Method was not available
Species:
guinea pig
Strain:
Dunkin-Hartley
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
albino Dunkin-Hartley guinea pigs
- Source: David Hall Limited, Burton-on-Trent, Staffordshire, U.K.
- Weight at study initiation: 333 - 393g
- Age: seven to eleven weeks
- Housing: groups of up to 4
- Diet: Guinea Pig FD1 Diet, Special Diet Services Limited, Witham, Essex, U.K. ad libitum
- Water: tap water ad libitum
- Acclimatisation period: five days,

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 to 25°C
- Humidity (%): 45 to 60%
- Photoperiod (hrs dark / hrs light): 12/12


IN-LIFE DATES: From: 16. March To: 26. April 1987
Route:
intradermal
Vehicle:
arachis oil
Concentration / amount:
1% / 2 x 0.1 mL
1% / 2 x 0.1 mL in arachis oild : Freund's Complete Adjuvant (FCA) 1:1
Day(s)/duration:
Day 1
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Route:
epicutaneous, occlusive
Vehicle:
petrolatum
Concentration / amount:
25% (w/w) in petroleum jelly B.P. / 0.2 to 0.3 mL


Day(s)/duration:
on Day 8 for 48 hours
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
petrolatum
Concentration / amount:
25% (w/w) in petroleum jelly B.P. / 0.1 to 0.2 mL
Day(s)/duration:
on Day 22 for 24 hours
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
Determination of primary not irritating concentration: 4
Determination of intradermal tolerability: 2
Control group: 10
Treatment group: 20
Positive control substance(s):
yes
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
25%
No. with + reactions:
14
Total no. in group:
20
Clinical observations:
yellow/green coloured staining of skin
Remarks on result:
positive indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
25%
No. with + reactions:
11
Total no. in group:
20
Clinical observations:
yellow/green coloured staining of skin; one animal not evaluable due to skin alterations was counted as positive
Remarks on result:
positive indication of skin sensitisation
Reading:
other: 3rd reading
Hours after challenge:
72
Group:
test chemical
Dose level:
25%
No. with + reactions:
4
Total no. in group:
20
Clinical observations:
yellow/green coloured staining of skin; one animal not evaluable due to skin alterations was counted as positive
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
25%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
yellow/green coloured staining of skin
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
25%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
yellow/green coloured staining of skin
Reading:
other: 3rd reading
Hours after challenge:
72
Group:
negative control
Dose level:
25%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
yellow/green coloured staining of skin

Yellow/green coloured staining of the skin was noted at the majority of test sample sites but did not prevent assessment of the skin responses.

Positive skin responses (erythema score >1) were noted at fourteen of the test sample sites on the test animals at the 24-hour observation. Slight loss of skin suppleness was also noted at one of these sites at this time.

A positive skin response had developed at one additional test sample site on the test animals at the 48-hour observation. A further observation was therefore made 72-hours after dressing removal but no additional positive

skin responses were noted. Common signs of desquamation and occasional signs of superficial cracking and thickening of the skin were apparent at the test sample sites on the test animals at both the 48 and 72-hour

observations.

No adverse skin reactions were noted at the vehicle control sites on the test animals or test sample or vehicle control sites on the control animals at the 24, 48 or 72-hour observations.

Bodyweight gains of surviving guinea pigs in the test group, between day 0 and day 24, were comparable to those observed in the control group animals over the same period.

Interpretation of results:
Category 1 (skin sensitising) based on GHS criteria
Conclusions:
The test substance caused positive reactions in 70%, 55% and 20% of animals after 24, 48, and 72 hours after removal of the test substance; it is hence considered to be a skin sensitiser.
Executive summary:

A study was performed to assess the skin sensitisation potential of the test sample in the albino guinea pig. The method used followed that described in the OECD Guidelines for Testing of Chemicals (1981) No. 406 "skin Sensitisation" - Magnusson and Kligman Maximisation Test.

 

Twenty test and ten control animals were used for the main study.

Following sighting studies, the following concentrations were used in the induction and challenge phases:

Intradermal Induction       1% (w/v) in arachis oil

Topical Induction             25% (w/w) in petroleum jelly

Topical Challenge             25% (w/w) in petroleum jelly

Yellow/green coloured staining of the skin was noted at the majority of test sample sites but did not prevent assessment of the skin responses.

Positive skin responses (erythema score >1) were noted at fourteen of the test sample sites on the test animals at the 24-hour observation. Slight loss of skin suppleness was also noted at one of these sites at this time.

A positive skin response had developed at one additional test sample site on the test animals at the 48-hour observation. A further observation was therefore made 72-hours after dressing removal but no additional positive

skin responses were noted. Common signs of desquamation and occasional signs of superficial cracking and thickening of the skin were apparent at the test sample sites on the test animals at both the 48 and 72-hour

observations.

No adverse skin reactions were noted at the vehicle control sites on the test animals or test sample or vehicle control sites on the control animals at the 24, 48 or 72-hour observations.

Bodyweight gains of surviving guinea pigs in the test group, between day 0 and day 24, were comparable to those observed in the control group animals over the same period.

The test substance caused positive reactions in 70%, 55% and 20% of animals after 24, 48, and 72 hours after removal of the test substance; it is hence considered to be a skin sensitiser.

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1988
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Qualifier:
according to guideline
Guideline:
EU Method B.6 (Skin Sensitisation)
GLP compliance:
yes (incl. QA statement)
Type of study:
Buehler test
Justification for non-LLNA method:
Method was not available
Species:
guinea pig
Strain:
Dunkin-Hartley
Remarks:
Pirbright White
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Winkelmann, Borchen, SPF breeding colony.
- Body weight at start of study: 315-408 g
- Age at start of study: 5-7 weeks
- Housing: in groups of four in macrolon cages (type 4) on soft wood granulate
- Diet: Altromin 3022 for guinea pigs, ad libitum
- Water: Tap water in plastic bottles, ad libitum
- Acclimation period: At least 7 d
- Animal identification: Fur marking and cage numbering

ENVIRONMENTAL CONDITIONS
- Temperature: 20-24°C
- Humidity: apprrox. 50%
- Photoperiod: 12 h light/dark cycle
- Air changes (per hr): ca 10
Route:
epicutaneous, occlusive
Vehicle:
other: Cremophore EL (2% v/v) in water for injection
Concentration / amount:
12.5% /0.5 mL
Day(s)/duration:
Day 1, Day 8, Day 15 - for 6 hours each
Adequacy of induction:
highest technically applicable concentration used
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
other: Cremophore EL (2% v/v) in water for injection
Concentration / amount:
12.5% / 0.5 mL
Day(s)/duration:
Day 29 for 6 hours
Adequacy of challenge:
other: highest technically applicable concentration used
No. of animals per dose:
Number of animals in test group: 12
Number of animals in 1st control group: 12
Number of animals in 2nd control group: 12

Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: on Day 1, 8, and 15 for 6 hours each
- Test groups: 1
- Control group: 2
- Site: flank
- Frequency of applications: every seven days
- Duration: 6 hours
- Concentrations: 12.5%

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: Day 29
- Exposure period: 6 hours
- Test groups: 1
- Control group: 2
- Site: left flank test substance, right flank vehicle
- Concentrations: 12.5%
- Evaluation (hr after challenge): 48 and 72

OTHER: thicknes of skin folds were measured during induction and before challenge and 48 and 72 hours after challenge
Reading:
1st reading
Hours after challenge:
48
Group:
test chemical
Dose level:
0%
No. with + reactions:
5
Total no. in group:
12
Reading:
1st reading
Hours after challenge:
48
Group:
test chemical
Dose level:
12.5%
No. with + reactions:
4
Total no. in group:
12
Clinical observations:
same animals which showed reactions with the vehicle alone
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
72
Group:
test chemical
Dose level:
0%
No. with + reactions:
4
Total no. in group:
12
Reading:
2nd reading
Hours after challenge:
72
Group:
test chemical
Dose level:
12.5%
No. with + reactions:
4
Total no. in group:
12
Clinical observations:
same animals which showed reactions with the vehicle alone
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
48
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
12
Reading:
1st reading
Hours after challenge:
48
Group:
negative control
Dose level:
12.5%
No. with + reactions:
1
Total no. in group:
12
Reading:
2nd reading
Hours after challenge:
72
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
12
Reading:
2nd reading
Hours after challenge:
72
Group:
negative control
Dose level:
12.5%
No. with + reactions:
1
Total no. in group:
12

Measurement of skin-fold thickness showed no difference between negative control and test group or vehicle and test substance trated flanks.

Body weight development was regular in all animals.

Interpretation of results:
GHS criteria not met
Conclusions:
Based on the study coducted, Disperse Violet 93:1 does not have sin sensitising properties.
Executive summary:

In a skin sensitization test in male guinea pigs (Buehler test) it was examined whether Disperse Violet 93:1 has a skin sensitizing effect.

Under occlusive conditions, three epicutaneous inductions were performed at an interval of 7 days and 2 weeks later a challenge treatment followed with a 12.5% test substance formulation to determine whether hypersensitivity (sensitization) has been induced.

The test sample was applied at a maximum suspendable and administrable concentration in an aqueous formulation to allow optimal skin contact. The concentration used is sufficiently high for a suspended solid, since the test sample came into contact with the skin in a sufficiently thick layer and well moistened with the method used. As the test substance stained the skin as a dye, skin reactions (redness) could not be determined after the inductions. As a substitute, the skin fold thickness was measured to determine thickening as a result of inflammatory processes in the skin. The results of these studies showed no evidence of test-substance-induced inflammatory skin reactions.

After the challenge treatment, a chemical depilation was performed to determine whether the skin discoloration could possibly be removed. This measure was successful so that a macroscopic evaluation of the skin could be carried out in addition to skin fold measurements.

After the challenge treatment, the skin fold measurements and the macroscopic findings of the skin provided no evidence of a test substance-induced hypersensitivity (sensitization) of the skin.

The slight skin redness observed in 4 animals of the test substance group occurred both on the test substance treated side and on the vehicle treated side. Another animal of this group reacted temporarily with a slight redness only on the vehicle treated side, and one animal of the control group reacted with a slight redness only at the test substance treated side. These findings can therefore not be attributed to hypersensitivity (sensitization).

The examinations carried out thus did not provide any evidence of a skin-sensitizing potential of the test substance.

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
December 1978
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions
Qualifier:
according to guideline
Guideline:
other: Stevens MA. Use of the Albino Guinea-pig to Detect the Skin-sensitizing Ability of Chemicals. British journal of industrial medicine 1967;24(3):189-202
Principles of method if other than guideline:
In a routine test for skin-sensitizing potential, the test substance was applied over three days to the ears of guinea-pigs, and the flanks have been challenged one week later with a range of concentrations of suspected sensitizing substance. The erythematous reaction produced 24 hours after challenge was rated and compared with that in unsensitized controls.
GLP compliance:
no
Remarks:
Study pre-dates GLP
Type of study:
other: ear/flank test
Justification for non-LLNA method:
Study available is over 12 years old.
Specific details on test material used for the study:
No further details specified in the study report.
Species:
guinea pig
Strain:
other: AlderleyPark strain albino guinea pigs
Sex:
not specified
Route:
epicutaneous, open
Vehicle:
N,N-dimethylformamide
Concentration / amount:
0.1 ml of a 10% w/v solution
Day(s)/duration:
3 days
Adequacy of induction:
not specified
No.:
#1
Route:
epicutaneous, open
Vehicle:
N,N-dimethylformamide
Concentration / amount:
0.2 ml
5% w/v, 0.1% w/v and 0.01% w/v
Day(s)/duration:
1 day
No. of animals per dose:
6 animals
Details on study design:
The test article (0.1 ml of a 10% w/v solution in dimethylformamjde) was applied daily by means of a glass syringe to the outer surface of each ear of 6 guinea pigs (animal numbers 1 - 6) for three days
(days 1, 2 and 3). On Day 8, 0.2 ml of the challenge solutions (5% w/v, 0.1% w/v and 0.01% w/v in dimethylformamide) was applied topically to 1 cm diameter circular areas on the clipped flanks of each of the same 6 animals. Solutions of test article were also applied in the same way on Day 8 to the clipped flanks of control animals (animal numbers 7 - 10) which had no previous treatment on the ears. The applications were made on both flanks of all 10 guinea pigs, with each concentration being applied to each flank. The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.
The erythema produced on each site was assessed 24 hours later (Day 9) and graded on a 6 point scale.
Challenge controls:
The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.
Positive control substance(s):
not specified
Positive control results:
Not specified.
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
5% w/v
No. with + reactions:
0
Total no. in group:
6
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.1% w/v
No. with + reactions:
0
Total no. in group:
6
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.01% w/v
No. with + reactions:
0
Total no. in group:
6
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
5% w/v
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.1% w/v
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.01% w/v
No. with + reactions:
0
Total no. in group:
4
Clinical observations:
None specified
Remarks on result:
no indication of skin sensitisation

Induction was carried out using a 10.0% w/v solution of the test substance in dimethylformamide (DMF). The subsequent challenge was accomplished using 5.0, 0.1 and 0.01% w/v solutions in DMF.

None of the animals showed a visible erythmic response or any signs of oedema.

Reading the result of the test was made difficult owing to pronounced skin staining with the test substance.

Histological examination of skin taken from the challenge sites showed no evidence of sensitisation.

Interpretation of results:
study cannot be used for classification
Conclusions:
No erythema was noted in any of the test or control animals. The test article was not considered to be a strong sensitiser.
Executive summary:

A study was carried out to determine the skin-sensitising potential of test article in the albino guinea pig. The study was performed in accordance with the ear/flank test method (Stevens).

 

The test article (0.1 ml of a 10% w/v solution in dimethylformamjde) was applied daily by means of a glass syringe to the outer surface of the ears of 6 guinea pigs (animal numbers 1 - 6) for three days (days 1, 2 and 3).

On Day 8, 0.2 ml of the challenge solutions (5% w/v, 0.1% w/v and 0.01% w/v in dimethylformamide) was applied topically to 1 cm diameter circular areas on the clipped flanks of each of the same 6 animals. Solutions of test article were also applied in the same way on Day 8 to the clipped flanks of control animals (animal numbers 7 - 10) which had no previous treatment on the ears. The applications were made on both flanks of all 10 guinea pigs, with each concentration being applied to each flank.

The highest concentration was applied closest to the posterior end of the animal while the lowest concentration was applied nearest the anterior end.

The erythema produced on each site was assessed 24 hours later (Day 9).

 

Results

No erythema was noted in any of the test or control animals. The test article was not considered to be a strong sensitiser.

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (sensitising)
Additional information:

Three studies for skin sensitising properties were conducted with Disperse Violet 93:1. Two of those studies were negative and one of these studies were positive.

The first skin sensitisation study performed in 1978 with Disperse Violet 93:1 (Br) with a purity of ca. 98% was conducted according to the ear/flank test method established by Stevens (Stevens MA. Use of the Albino Guinea-pig to Detect the Skin-sensitizing Ability of Chemicals. British journal of industrial medicine 1967;24(3):189-202) in albino guinea pigs. For this purpose, the test article (0.1 mL of a 10% w/v solution in dimethylformamide) was applied daily by means of a glass syringe to the outer surface of the ears of 6 guinea pigs for three days. On Day 8, 0.2 mL of the challenge solutions (5% w/v, 0.1% w/v and 0.01% w/v in dimethylformamide) was applied topically to 1 cm diameter circular areas on the clipped flanks of each of the same 6 animals. Solutions of test article were also applied in the same way on Day 8 to the clipped flanks of 4 control animals which had no previous treatment on the ears. The applications were made on both flanks of all 10 guinea pigs, with each concentration being applied to each flank. The treated skin at each site was assessed 24 hours later (Day 9). No erythema was noted in any of the test or control animals. The test article was thus not considered to be a strong sensitiser.

 

The second study performed in 1987 with bulk material out of the Disperse Violet 93:1 (Br) synthesis without information of its purity, was performed in the guinea pig maximisation test according to Magnusson & Kligman (OECD Guidelines for Testing of Chemicals (1981) No. 406 "skin Sensitisation"). Twenty test and ten control animals were used for the main study. Following sighting studies, the intradermal induction was carried out with 1% (w/v) in arachis oil and in Freund’s Adjuvant. The topical induction and challenge was carried out with a concentration of 25% (w/w) in petroleum jelly. The skin was assessed 24, 48, and 72 hours after end of the challenge exposure. Yellow/green coloured staining of the skin was noted at the majority of test sample sites but did not prevent assessment of the skin responses. Positive skin responses (erythema score >1) were noted at fourteen of the test sample sites on the test animals at the 24-hour observation. Slight loss of skin suppleness was also noted at one of these sites at this time. A positive skin response had developed at one additional test sample site on the test animals at the 48-hour observation. A further observation was therefore made 72-hours after dressing removal but no additional positive skin responses were noted. On contrary, only 4 animals with skin reactions were seen at that observation point. Common signs of desquamation and occasional signs of superficial cracking and thickening of the skin were apparent at the test sample sites on the test animals at both the 48 and 72-hour observations. No adverse skin reactions were noted at the vehicle control sites on the test animals or test sample or vehicle control sites on the control animals at the 24, 48 or 72-hour observations. Bodyweight gains of surviving guinea pigs in the test group, between day 0 and day 24, were comparable to those observed in the control group animals over the same period. As the test substance caused positive reactions in 70%, 55% and 20% of animals after 24, 48, and 72 hours after removal of the test substance; it is considered to be a skin sensitiser.

 

The third skin sensitising study performed in 1988 with Disperse Violet 93:1 (Br) with a purity of ca. 91% was conducted in the Bühler test in 12 male guinea pigs per group according to OECD Guidelines for Testing of Chemicals (1981) No. 406 "skin Sensitisation". Under occlusive conditions, three epicutaneous inductions were performed at an interval of 7 days and 2 weeks later a challenge treatment followed with a 12.5% test substance formulation to determine whether hypersensitivity (sensitization) has been induced. The test sample was applied at a maximum suspendable and administrable concentration in an aqueous formulation to allow optimal skin contact. The concentration used is sufficiently high for a suspended solid, since the test sample came into contact with the skin in a sufficiently thick layer and well moistened with the method used. As the test substance stained the skin as a dye, skin reactions (redness) could not be determined after the inductions. As a substitute, the skin fold thickness was measured to determine thickening as a result of inflammatory processes in the skin. The results of these studies showed no evidence of test-substance-induced inflammatory skin reactions. After the challenge treatment, a chemical depilation was performed to determine whether the skin discoloration could possibly be removed. This measure was successful so that a macroscopic evaluation of the skin could be carried out in addition to skin fold measurements. After the challenge treatment, the skin fold measurements and the macroscopic findings of the skin provided no evidence of a test substance-induced hypersensitivity (sensitization) of the skin. The slight skin redness observed in 4 animals of the test substance group occurred both on the test substance treated side and on the vehicle treated side. Another animal of this group reacted temporarily with a slight redness only on the vehicle treated side, and one animal of the control group reacted with a slight redness only at the test substance treated side. These findings can therefore not be attributed to hypersensitivity (sensitization). The examinations carried out thus did not provide any evidence of a skin-sensitizing potential of the test substance.

 

Based on the data presented, the test substance Disperse Violet 93:1 (Br) seems to react as a skin sensitiser at concentration of ≥ 25% if the animals were pre-treated with an adjuvant. Without adjuvant, concentrations of up to 12.5% did not cause skin sensitising effects.

 

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the data presented, the test substance Disperse Violet 93:1 (Br) seems to react as a skin sensitiser at concentration of ≥ 25% if the animals were pre-treated with an adjuvant. Without adjuvant, concentrations of up to 12.5% did not cause skin sensitising effects.

Although the outcome of the various skin sensitisation study does not give a clear picture, it was concluded to classify the test substance as skin sensitiser, as Disperse Blue 165:1, for which Disperse Violet 93:1 is the precursor in the synthesis process, was positive in the Local Lymph Node assay.