Registration Dossier

Administrative data

Description of key information

A key skin sensitisation study was performed with Dunkin Hartley guinea pigs using the GPMT method of Magnusson and Kligman (according to OECD guideline 406; Sanders, 2000). The test substance produced a 0% sensitisation rate to guinea pig skin.

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:
key study
Study period:
From October 25, 1999 to December 3, 1999
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.6 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
Study was performed before the publication of guideline mentioning LLNA method as the preferred method for skin sensitisation testing.
Species:
guinea pig
Strain:
Dunkin-Hartley
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: David Hall Limited, Burton-on-Trent, Staffordshire, UK
- Age at study initiation: 8-12 weeks old
- Weight at study initiation: 326-392 g
- Housing: singly or in pairs in solid-floor polypropylene cages furnished with woodflakes
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least five days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-23 ºC
- Humidity (%): 30-70 %
- Air changes (per hr): approximately fifteen changes per hour
- Photoperiod (hrs dark / hrs light): twelve hours continuous light and twelve hours darkness
Route:
intradermal
Vehicle:
water
Concentration / amount:
Intradermal induction: 0.1 % w/v in distilled water
Topical induction: 75 % in distilled water
Topical Challenge: 5 % and 2 % w/v in distilled water
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
Intradermal induction: 0.1 % w/v in distilled water
Topical induction: 75 % in distilled water
Topical Challenge: 5 % and 2 % w/v in distilled water
No. of animals per dose:
20 animals/dose and 10 animals as control group.
Details on study design:
RANGE FINDING TESTS:
- Selection of Concentration for Intradermal Induction: Four concentrations of test material were investigated (0.1 %, 0.5%, 1 % and 5% w/w in distilled water). A total of four guinea pigs were used, each guinea pig receiving four 0.1 ml injections of only one concentration of test material. The degree of erythema at the injection sites was assessed approximately 24, 48 and 72 hours and 7 days after injection. The selected concentration for the main study was 0.1% w/w in distilled water.

- Selection of Concentration for Topical Induction: Two guinea pigs (intradermally injected with Freund's Complete Adjuvant fifteen days earlier) were treated with the undiluted test material and three preparations of the test material (75%, 50% and 25% w/w in distilled water). The highest concentration (75 w/w in distilled water) producing only mild to moderate dermal irritation was selected for the topical induction stage of the main study.

-Selection of Concentration for Topical Challenge: The undiluted test material and two preparations of the test material (75%, 50% and 25% w/w in distilled water) were applied to the clipped flanks of two guinea pigs under occlusive dressings for an exposure period of 24 hours. Two further guinea pigs were treated with four lower concentrations of the test material (25%, 10%, 5% and 2% w/w in distilled water). The highest non-irritant concentration of the test material and one lower concentration were selected for the topical challenge stage of the main study.


MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: two exposures: intradermal injection and topical application
- Exposure period: 21 days
- Test groups: 20
- Control group: 10
- Site: approximately 40mm x 60 mm on the shoulder region
- Frequency of applications: three injections was applied (day 0) and one week later (day 7), a topical application of the test substance by an occlusive dressing of 48 hours was made.
- Duration: 21 days
- Concentrations: a) FCA plus distilled water in the ratio 1:1; b) distilled water and c) 50% v/v formulation of distilled water in 1:1 FCA/distilled water.

B. CHALLENGE EXPOSURE
- No. of exposures: one exposure per each concentration and each animal.
- Day(s) of challenge: 3 days
- Exposure period: 24 hours
- Test groups: two test groups.
- Control group: one control group of 10 animals
- Site: 20 mm x 20 mm
- Concentrations: 5% and 2 % (w/v, test substance in distilled water)
- Evaluation (hr after challenge): 72 hours from the start of the challenge application.
Challenge controls:
The vehicle (distilled water) alone was applied
Positive control substance(s):
yes
Remarks:
(2-mercaptobenzothiazole)
Positive control results:
The positive control material induced a sensitisation response in the different groups with an incidence of sensitisation between 70 and 100%.
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
5 %
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
No erythema, no oedema or other reactions were noted
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 5 %. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: No erythema, no oedema or other reactions were noted.
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
5 %
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
No erythema, no oedema or other reactions were noted
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 5 %. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: No erythema, no oedema or other reactions were noted.

Intradermal Induction-Individual Skin Reactions

 

Test Animals Results

INDUCTION CONCENTRATION: 0.1% w/w

VEHICLE: DISTILLED WATER

Grade of Erythema at Observation Time

Animal Number

24 Hours

48 Hours

 

Left Side

Right Side

Left Side

Right Side

1

1

1

1

0

2

1

2

0

1

3

2

1

1

0

4

1

1

0

0

5

2

2

1

1

6

1

1

0

0

7

2

2

1

1

8

2

2

1

1

9

2

1

1

1

10

2

1

1

1

11

2

1

1

1

12

1

2

0

1

13

2

1

1

0

14

2

2

1

1

15

1

1

0

0

16

2

1

1

0

17

2

2

0

0

18

1

1

0

0

19

2

2

0

0

20

2

2

0

0

Control Animal Results

Animal Number

Grade of Erythema at Observation Time

24 Hours

48 Hours

Left Side

Right Side

Left Side

Right Side

21

0

0

0

0

22

0

1

0

0

23

0

1

0

0

24

1

1

0

0

25

1

1

0

0

26

1

0

0

0

27

0

0

0

0

28

1

1

0

0

29

0

0

0

0

30

0

0

0

0

 

 

 Topical Induction ¿Individual Skin Reactions

 

Test Animals Results

INDUCTION ONCENTRATION: 75% w/w

VEHICLE: DISTILLED WATER

 

Skin Reactions (Hours After Removal of Dressing)

Animal Number

1Hour

24Hours

 

Er

Oe

Other

Er

Oe

Other

1

2

0

Bs

1

0

-

2

2

0

Bs

1

0

-

3

1

0

-

0

0

-

4

2

0

Bs

1

0

-

5

2

0

Bs

0

0

-

6

2

0

Bs

1

0

-

7

2

0

Bs

0

0

-

8

1

0

Bs

0

0

-

9

2

0

Bs

1

0

-

10

2

0

8s

1

0

-

11

2

0

Bs

1

0

-

12

1

0

-

0

0

-

13

2

0

Bs

1

1

Sp

14

2

1

Bs

*

*

*

15

2

0

Bs

1

0

-

16

2

0

Bs

2

0

-

17

1

0

-

1

0

-

18

1

0

-

1

0

-

19

2

0

Bs

2

0

-

20

2

0

Bs

1

0

-

Er: erythema

Bs: bleding from intradermal injection sites

Oe: oedema

Sp: hardened light brown coloured scab, caused by animal scratching

*: no data, animal killed for human reasons Day 9

-: no other reaction noted

 

Control Animal Results

VEHICLE: DISTLLED WATER

 

Skin Reactions (Hours After Removal of Dressing)

Animal Nº

1Hour

24Hours

 

Er

Oe

Other

Er

Oe

Other

21

0

0

Bs

0

0

-

22

0

0

Bs

0

0

-

23

0

0

-

0

0

-

24

0

0

-

0

0

-

25

0

0

Bs

0

0

-

26

0

0

-

0

0

-

27

0

0

-

0

0

-

28

0

0

Bs

0

0

-

29

0

0

-

0

0

-

30

0

0

-

0

0

-

Er: erythema

Oe. Oedema

-: no other reaction noted

Bs: bleeding from intradermal injection sites

Interpretation of results:
not sensitising
Conclusions:
The test substance produced a 0% (0/19) sensitisation rate to guinea pig skin. Therefore, it is not classified according to CLP Regulation.
Executive summary:

The skin sensitisation study for the test substance was performed with Dunkin Hartley guinea pigs using the method GPMT (Guinea Pigs Maximisation test) of Magnusson and Kligman. Based on the results of range finding test, the concentrations chosen for the different phases of the study were: 0.1 % w/w in distilled water for the intradermal induction, 75 % w/w in distilled water for the Topical Induction step, and 5% and 2% w/w in distilled water for the Topical Challenge phase. The main test was carried out with thirty guinea pigs, twenty for the test and ten as control group. Individual reactions observed after intradermal induction and after topical induction were recorded, as well as the bodyweight of each animal at the start and at the end of the study. After intradermal induction, a discrete to moderate and confluent erythema was noted in all test group animals at the 24-hours observation and in twelve group animals at 48-hour observation. A discrete to moderate and confluent erythema with and without very slight oedema was noted at the topic induction sites of all test group animals at the 1-hour observation and fourteen test group animals at the 24-hour observation. No signs of erythema or oedema were noted in the control group. No skin reactions were noted at the challenge sites of the test or control group animals at the 24 or 48-hour observation from the start of the challenge application.

The test substance produced a 0% (0/19) sensitisation rate to guinea pig skin.

Endpoint:
skin sensitisation: in vitro
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

Key study: according to OECD guideline 406 and EU guideline B.6. The test substance produced a 0% sensitisation rate to guinea pig skin.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

Based on the available results, the substance is not classified for skin sensitisation according to CLP Regulation.