Registration Dossier

Toxicological information

Skin sensitisation

Currently viewing:

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1988
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1988
Report Date:
1988

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
yes
Remarks:
(Clinical observations e.g. systemic reactions were not reported)
Qualifier:
according to
Guideline:
other: EEC directive 79/831
Deviations:
yes
Remarks:
(Clinical observations e.g. systemic reactions were not reported)
GLP compliance:
no
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
Data from a reliable in vivo test conducted before the enforcement of Commission Regulation (EU) 640/2012 of 06 July 2012 amending, for the purpose of its adaptation to technical progress, Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) are available.

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: solid
Specific details on test material used for the study:
Test article:FAT 40075/B
Batch No.: EN 12781.72
Contents of active: 74.5 % ingredients:
Physical properties: solid;insoluble in water; pH: 6.0 (1 g/l water)
Storage conditions: Room temperature
Validity: Jan 1993
Test material received: Jan 21, 1988

In vivo test system

Test animals

Species:
guinea pig
Strain:
other: Pirbright White Strain (Tif: DHP)
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: CIBA-GEIGY LTD. Tierfarm, 4334 Sisseln, Switzerland
- Age at study initiation: Approximately 10 weeks
- Weight at study initiation: 336-439 g
- Housing: Housed individually in Macrolon cages (Type 3)
- Diet: Standard guinea pig pellets- NAFAG No. 846, Gossau SG, ad libitum
- Water: Fresh water, ad libitum
- Acclimation period: 1 week

SENSITIVITY OF STRAIN
- The sensitivity of the strain is checked every six months with Paraphenylene-diamine or Potassium-dichromate.

ENVIRONMENTAL CONDITIONS
- Temperature: 22 ± 3 °C
- Humidity: 30 - 70 %
- Photoperiod: 12 h light/12 h dark

IN-LIFE DATES: From March 14, 1988 to April 15, 1988

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal
Vehicle:
other: Physiological saline
Concentration / amount:
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:
other: vaseline
Concentration / amount:
30 %
Day(s)/duration:
day 8
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
other: vaseline
Concentration / amount:
3 %
Day(s)/duration:
day 22
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
Main test: 10 control animals and 20 treated animals (10 males and 10 females).
Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE
The induction was a two-stage operation. First, intradermal injections (into the neck region); second, closed patch exposure over the injection sites one week later.

First induction, intradermal injection:
Three pairs of intradermal injections (0.1 mL per injection) were made simultaneously into the shaved neck of the animals as follows:
- adjuvant and saline (1:1)
- test substance in physiological saline
- test substance in the adjuvant/saline mixture
Concentration of test substance in physiological saline and adjuvant mixture: 1 %

Second induction, epidermal application:
One week later test substance was incorporated in vaseline and applied on a filter paper patch to the neck of the animals (patch 2 x 4 cm²; occluded administration for 48 h).
Dose of application: Approximately 0.4 g paste of 30 % test substance in vaseline.

B. CHALLENGE EXPOSURE
Two weeks after the epidermal induction application the animals were tested on the flank with test substance in vaseline and the vehicle alone (patch 2 x 2 cm²; occluded administration for 24 h).
Dose of application: Approximately 0.2 g paste of 3 % test substance in vaseline
The concentrations of the test substance for the induction and challenge periods were determined on separate animals.

Control group:
A control group was treated with adjuvant and the vehicle during the induction period. During the challenge period the group was treated with the vehicle as well as with the test substance (at least 10 animals) to control the maximum subirritant concentration of the test substance in adjuvant treated animals.

PRELIMINARY STUDY:
- Separate animals were treated with test substance for the evaluation of the primary irritation threshold concentration.
- Concentrations of 30, 10 and 3 % in vaseline were tested. Erythema reactions were observed at 30 and 10 % . No erythema was induced at the lower concentrations.
- Therefore, 3 % was used as the maximum subirritant concentration for the challenge application.

OBSERVATIONS:
24 h after removing the dressings, the challenge reactions were graded according to the Draize scoring scale. A second evaluation was made 48 h after removing the dressings. The sensitizing potential of the test substance was classified according to the grading of Magnusson and Kligman. The body weight was recorded at start and end of the test.
Positive control substance(s):
no
Remarks:
the sensitivity of the strain is checked every six months with Paraphenylene-diamine or Potassium-dichromate.

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
Intradermal induction: 1 %; epicutaneous induction: 30 %, challenge: 3 %
No. with + reactions:
20
Total no. in group:
20
Remarks on result:
positive indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
Intradermal induction: 1 %; epicutaneous induction: 30 %, challenge: 3 %
No. with + reactions:
20
Total no. in group:
20
Remarks on result:
positive indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
no indication of skin sensitisation
Group:
positive control
Remarks on result:
not measured/tested

Applicant's summary and conclusion

Interpretation of results:
Category 1A (indication of significant skin sensitising potential) based on GHS criteria
Conclusions:
The test substance was found to have sensitised 100 % of the test animals at both 24 and 48 h readings. Hence, FAT 40075/B was considered to be a skin sensitiser.
Executive summary:

A guinea pig maximization study was conducted to evaluate the skin sensitisation potential of the test substance (at ca. 74.5 % purity) according to OECD Guideline 406 and EEC Directive 79/83. Based on the results of a preliminary study, 1 and 30 % concentrations were selected for intradermal and epidermal induction phases. The highest non-irritating test substance concentration used for occluded epidermal application during challenge exposure was 3 %. Skin reactions were graded using Draize scoring at 24 and 48 h after removal of dressing after challenge. In the treated group, 20/20 animals (10/sex) showed skin reactions both 24 and 48 h after removing the dressings. Scaling was observed in 2/10 males and 6/10 females at 48 h. No skin reactions were observed in control animals (0/10, 5/sex) or in the vehicle only challenged flanks in the test substance treated animals. No unscheduled deaths, changes in body weight were observed during the study period. Under the study conditions, the test substance was found to have sensitised 100 % of the test animals at both 24 and 48 h readings. Hence, FAT 40075/B was considered to be a skin sensitiser.