Registration Dossier

Administrative data

Description of key information

The test substance is not considered to be sensitising.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Remarks:
Buehler test
Type of information:
experimental study
Adequacy of study:
key study
Study period:
From May 02, 2005 to October 04, 2005
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Reason / purpose:
reference to other study
Qualifier:
according to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OPPTS 870.2600 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
Buehler test
Justification for non-LLNA method:
The study was conducted before the formal requirement for LLNAs was implemented.
Specific details on test material used for the study:
- Physical state: Clear yellow liquid
- Analytical purity: 80.9% w/w active substance
- Purity test date: 16 September, 2004
- Lot/batch No.: J2220459
- Stability under test conditions: The test substance is hydrolytically and photolytically stable under the conditions of this study and has been shown to be stable in aqueous, alcohol and alcohol/aqueous solutions for extended periods, e.g. at least five years under standard laboratory conditions.
Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
Test animals
- Source: Elm Hill Breeding Labs, Chelmsford, MA, USA
- Age at study initiation: Young adult animals
- Weight at study initiation: 327-399 g
- Housing: The animals were group housed in suspended stainless steel caging with mesh floors or plastic perforated bottom caging which conform to the size recommendations according to ‘Guide for the care and use of laboratory animals DHEW (NIH). Litter paper was placed beneath the cage and was changed at least three times/wk.
- Diet: Pelleted Purina guinea pig chow # 5025, ad libitum
- Water: Filtered tap water, ad libitum
- Acclimation period: 3-17d

Environmental conditions
- Temperature: 19-22°C
- Humidity: 31-58%
- Photoperiod (hrs dark / hrs light): 12-h light/dark cycle

In-life dates: From: May 2, 2005 to: June 10, 2005
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
Induction: 1% w/w mixture of the test substance in distilled water (0.4 mL)
Challenge: 0.25% w/w mixture of the test substance in distilled water (0.4 mL)
Day(s)/duration:
6h exposure, observations 24 and 48h after exposure
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
Induction: 1% w/w mixture of the test substance in distilled water (0.4 mL)
Challenge: 0.25% w/w mixture of the test substance in distilled water (0.4 mL)
Day(s)/duration:
6h exposure, observations 24 and 48h after exposure
No. of animals per dose:
20 animals in the test substance group and 10 animals in the control group
Details on study design:
Range finding tests:
A preliminary irritation study was performed to determine the highest non-irritating concentration. 8 guinea pigs (5 males and 3 females) were exposed for 6 h period to various concentrations of the test substance as follows: 100, 75, 50, 25, 1.25, 1.0, 0.75, 0.25 and 0.10%.w/w in distilled water. The fur was removed by clipping the dorsal area and flanks of each guinea pig. The area was divided into two or four test sites on each animal. Two to four concentrations of the test substance were applied to the sites. 0.4 mL of each concentration was applied to a test site using a 25 mm Hill Top Chamber. The test sites were wrapped with non-allergenic adhesive tape. All animals were evaluated at approximately 24 hours, 2 days and one animal on Day 5. Each site was evaluated for erythema.

Main study
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: 6h
- Test groups: One test group, including 20 guinea pigs
- Control group: No control animals were employed in induction phase
- Site: Left side of each animal
- Frequency of applications: Once a week for three consecutive weeks
- Duration: 6 h/application
- Concentrations: 1 % w/w mixture of the test substance in distilled water (0.4 mL)
- Procedure for application: Once a week for three weeks, 0.4 mL of a 1% w/w mixture of the test substance in distilled water was applied to the left side of each animal. Due to residual irritation from the previous doses, the dose site was moved each induction. Approximately 24 and 48h after each induction exposure, the skin was evaluated for local reactions (erythema).

B. CHALLENGE EXPOSURE
- No. of exposures: One
- Day(s) of challenge: Twenty-seven days after the first induction dose
- Exposure period: 6h
- Test groups: One test group (20 animals) exposed with 0.25% w/w mixture of the test substance in distilled water
- Control group: One naive control group (10 animals) exposed with 0.25% w/w mixture of the test substance in distilled water
- Site: The test substance was applied to a naïve site on the right side of each test animal.
- Concentrations: 0.25% w/w mixture of the test substance in distilled water
- Evaluation (hr after challenge): These sites were evaluated for a sensitisation response approximately 24 and 48h after the challenge exposure.

Other: Historical Positive Control Validation Study: The procedures used in this study were validated using alpha-Hexylcinnamaldehyde Technical (HCA) grade as a positive control substance. A positive control validation study is run at no less than six months intervals at the testing laboratory. The results from the most recent positive control validation study performed on March 2005 are provided in the study report.
Challenge controls:
10 naive animals exposed with 0.25% w/w mixture of the test substance in distilled water
Positive control substance(s):
yes
Remarks:
alpha-hexylcinnamaldehyde
Positive control results:
Induction: Very faint to faint erythema (0.5-1.0) was noted for all of the positive control sites during the induction phase.
Challenge: Four of nine positive control animals exhibited signs of skin sensitisation response 24 and 48h after exposure. Very faint erythema was observed for four other sites after challenge. Very faint erythema was observed in three of five positive control naive test sites after 24h. Irritation persisted at one of these sites through 48h.
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
0.25% w/w mixture of the test substance in distilled water
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
No animals with positive response
Remarks on result:
other: see Remark
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0.25% w/w mixture of the test substance in distilled water
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
No animals with positive response
Remarks on result:
other: see Remark
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
0.25% w/w mixture of the test substance in distilled water
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
No animals with positive response
Remarks on result:
other: see Remark
Remarks:
Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0.25% w/w mixture of the test substance in distilled water. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: No animals with positive response .
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
0.25% w/w mixture of the test substance in distilled water
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
No animals with positive response
Remarks on result:
other: see Remark
Remarks:
Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 0.25% w/w mixture of the test substance in distilled water. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: No animals with positive response .

Summary of results in the main study:

- Induction Phase: Very faint to faint erythema (0.5-1.0) was observed for all sites during the induction phase.

- Challenge Phase: 

Test group: None of the test animals exhibited a positive skin sensitisation response (score greater than 0.5) at 24 or 48h after challenge. Very faint erythema (0.5) was noted in 9 out of 20 test animals at 24h after challenge. Similar irritation persisted at two sites through 48h.

Naive Control group: Very faint erythema (0.5) was observed in 5 out of 10 test animals at 24h after challenge. Similar irritation persisted at two sites through 48h.

Table 1. The severity index of test and control group

Treatment

Severity

24 h

48 h

Test

0.23

0.05

Control

0.25

0.10

Conclusions:
Under the study conditions, the test substance was determined to be non-sensitising in a Buehler test when applied topically to albino Hartley guinea pigs.
Executive summary:

A study was conducted to determine the skin sensitisation potential of the test substance according to OECD Guideline 406 and US EPA OPPTS 870.2600 (Buehler test), in compliance with GLP. The study was conducted in two phases, with induction and challenge exposures. To determine the highest non-irritating concentration (HNIC) for the challenge phase, a preliminary irritation study was performed with 8 guinea pigs. The concentrations used were 100, 75, 50, 25, 1.25, 1.0, 0.75, 0.25 and 0.10%. w/w in distilled water. After treatment, the application sites were evaluated and scored. During the induction phase of the main study, 0.4 mL of a 1% w/w mixture of the test substance in distilled water was applied to the left side of each animal, once per week for three weeks. Twenty-seven days after the first induction dose, 0.4 mL of a 0.25% w/w (HNIC) mixture of the test substance in distilled water was applied to a naïve site on the right side of each test animal for challenge exposure. Ten additional animals exposed with 0.25% w/w mixture of the test substance in distilled water served as naive control group in the challenge phase only. Approximately 24 and 48 h after each induction and challenge dose, the animals were scored for erythema. Very faint to faint erythema (0.5 to 1) was observed in all test animals during induction. None of the test animals exhibited a positive skin sensitisation response (score greater than 0.5) at 24 or 48 h after challenge. Under the test conditions, the test substance was determined to be non-sensitising when applied topically to albino Hartley guinea pigs (Durando, 2005).

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Remarks:
Modified Draize test
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1974
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to
Guideline:
EU Method B.6 (Skin Sensitisation)
Version / remarks:
Cited as Directive 84/449/EEC, B.6
Deviations:
no
GLP compliance:
no
Type of study:
other: Modification of the Draize technique (Draize, Woodward and Calvery 1944 NAS-NRC 1964).
Justification for non-LLNA method:
The Local Lymph Node Assay (LLNA; TG 429) was adopted in 2002.
Specific details on test material used for the study:
- ca. 50% Cocobenzyldimethylammonium chloride (CAS no.: 61789-71-7) in water.
- Test subtance is based on full cocoalkyl chain.
- Chainlength distribution of full coco: C8: 5%; C10: 6%; C12: 50%; C14: 19%; C16: 10%; C18:10%.
Species:
guinea pig
Route:
intradermal
Vehicle:
water
Concentration / amount:
Induction 0.1% intracutaneous
Challenge 0.1% intracutaneous
Day(s)/duration:
1 day
Route:
intradermal
Vehicle:
water
Concentration / amount:
Induction 0.1% intracutaneous
Challenge 0.1% intracutaneous
Day(s)/duration:
1 day
No. of animals per dose:
6
Details on study design:
- 1st application: Induction 0.1 % intracutaneous
- 2nd application: Challenge 0.1 % intracutaneous
For the induction phase, 0.1 mL of a concentration of 0.1% of test substance in water was injected intradermally into the back of each six guinea pigs. This procedure was repeated every other days, using a different injection site on each occasion, until a total of nine injections had been given. Injection sites were examined 24h after each injection and scored for erythema and oedema using the Draize scale.
After completion of this series of priming injections the animals remained untreated for two weeks, and were then given a single challenge intradermal injection of the same concentration and volume as for induction. Injection sites were examined 24h after this challenge dose as before for erythema and oedema. The effects were compared to those produced by the priming doses in order to determine whether sensitisation had been produced.
Positive control substance(s):
no
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
0.1%
Remarks on result:
other: See 'Any other information on results incl. tables'

Modified Draize test:

- The priming injections elicited very slight to well defined erythema, and very slight to slight oedma on all occasions.
- The challenge dose produced a well defined erythema and very slight oedema in all occasions.

As the challenge doses did not produce any greater reaction in any animal, it may be concluded that is not a sensitising
agent under the conditions of this experiment.

Conclusions:
Under the study conditions, the test substance was not considered sensitizing to guinea pig skin.
Executive summary:

A study was conducted to determine the skin sensitisation potential of the test substance according to EU Method B.6 (modified Draize test). For the induction phase, 0.1 mL of 0.1% test substance in water was injected intradermally into the back of each six guinea pigs. This procedure was repeated every other day, using a different injection site on each occasion, until a total of nine injections had been given. Injection sites were examined 24 h after each injection and scored for erythema and oedema using the Draize scale. After a two week interval, a single challenge intradermal injection of the same concentration and volume was given as for induction. Injection sites were examined 24 h after this challenge dose as before for erythema and oedema. The effects were compared to those produced by the priming doses in order to determine whether sensitisation had been produced. The priming injections elicited very slight to well defined erythema, and very slight to slight oedema on all occasions. The challenge dose produced a well-defined erythema and very slight oedema in all occasions. However, the challenge doses did not produce any greater reaction in any animal. Under the study conditions, the test substance was not considered sensitizing to guinea pig skin (Thomas, 1974).

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Remarks:
Magnusson and Kligman standard method
Type of information:
other: published data
Adequacy of study:
supporting study
Study period:
1986
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
according to
Guideline:
other: Magnusson and Kligman standard method
Deviations:
yes
Remarks:
The actual concentrations are not given, and the method of establishing the used concentrations is not specified besides that 'in all cases non-irritating concentrations were chosen'.
GLP compliance:
no
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
The Local Lymph Node Assay (LLNA; TG 429) was adopted in 2002
Specific details on test material used for the study:
- Alkylbenzyldimethyl ammonium chloride, obtained from Ardrich chemical company, Milwaukee.
Species:
guinea pig
Strain:
other: Albino
Sex:
female
Details on test animals and environmental conditions:
- Age : Less 4 month old, 
- Body weight: approximately 400g
Route:
intradermal and epicutaneous
Vehicle:
physiological saline
Concentration / amount:
Day 1: intracutaneous injection of 0.1 mL of 0.1% test substance in isotonic saline with Freund's complete adjuvant (1:1).
Day 7: epicutaneous occlusive application for 48h with 0.3 mL of 0.1% test substance in ethylene glycol monomethylether, water, Tween 80 (180/180/40) v/v. 
Day 21: epicutaneous open challenge with 0.05 mL of test substance in water.
Route:
epicutaneous, open
Vehicle:
physiological saline
Concentration / amount:
Day 1: intracutaneous injection of 0.1 mL of 0.1% test substance in isotonic saline with Freund's complete adjuvant (1:1).
Day 7: epicutaneous occlusive application for 48 h with 0.3 mL of 0.1% test substance in ethylene glycol monomethylether, water, Tween 80 (180/180/40) v/v. 
Day 21: epicutaneous open challenge with 0.05 mL of test substance in water.
No. of animals per dose:
20
Details on study design:
1st application: Induction intracutaneous
2nd application: Induction occlusive epicutaneous
3rd application: Challenge open epicutaneous
- The test substance was tested in a GPMT test of Magnusson and Kligman:  
Day 1: intracutaneous injection of 0.1 mL of 0.1% test substance in isotonic saline with Freund's complete adjuvant (1:1) on the shaved part of the guinea pig flank (approximately 6 x 4 cm). 
Day 7: epicutaneous occlusive application for 48 h with 0.3 mL of 0.1% test substance in ethylene glycol monomethylether, water, Tween 80 (180/180/40) v/v. 
Day 21: epicutaneous open challenge with 0.05 mL of test substance in water at the shaved ventral side of the animal. The response was monitored after 24 and 48h next to a control group of 10 animals. Concentrations were previously ascertained by both intracutaneous and epicutaneous applications to determine irritative toxicity in three animals at 24 and 48h, respectively. In all cases non-irritating concentrations were chosen. Actual concentrations used not given.
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
No. with + reactions:
4
Total no. in group:
20
Clinical observations:
slight erythema
Remarks on result:
other: slight erythema
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
No. with + reactions:
2
Total no. in group:
20
Clinical observations:
slight macular erythema
Remarks on result:
other: slight macular erythema

Results: 

At 24h after challenge, 4/20 animals showed a positive response consisting of slight erythema. 

After 48h, 2/20 animals showed a slight macular erythema.

Conclusion: non-sensitising.

Conclusions:
Under study conditions, the test substance was not considered to be a skin sensitiser in a guinea pig maximization test (Magnusson and Kligman method).
Executive summary:

A study was conducted to determine the skin sensitisation potential of the test substance according to the Magnusson and Kligman method (guinea pigs maximisation test). Female albino guinea pigs received on Day 1 an intracutaneous injection of 0.1 mL of 0.1% test substance in isotonic saline with Freund's complete adjuvant (1:1) on the shaved part of the flank (approximately 6 x 4 cm). On Day 7, animas were applied an epicutaneous occlusive application for 48 h with 0.3 mL of 0.1% test substance in ethylene glycol monomethylether, water, Tween 80 (180/180/40) v/v. Finally, on Day 21, guinea pigs were challenged epicutaneously (open application) with 0.05 mL of test substance in water at the shaved ventral side of the animal. The response was monitored after 24 and 48 h next to a control group of 10 animals. Concentrations were previously ascertained by both intracutaneous and epicutaneous applications to determine irritation potential in three animals at 24 and 48 h, respectively. In all cases non-irritating concentrations were chosen. At 24 h after challenge, 4/20 animals showed a positive response consisting of slight erythema. After 48 h, 2/20 animals showed a slight macular erythema. Under the conditions of this study, the test substance was negative for skin sensitization (Schallreuter, 1996).  

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1969
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Principles of method if other than guideline:
The skin of 5 guinea pigs was shaved, and animals received 10 priming doses (first intracutaneous injection 0.05 mL, other 9 injections 0.1 mL) of a 0.1% aqueous solution every other d in an area on the back site (3-4 square cm). Two weeks after the 10th injection, a challenge injection of 0.05 mL was given at another area. Skin readings were made 24 h after each injection. The challenge reaction was compared with the 10 previous injections.
GLP compliance:
no
Type of study:
intracutaneous test
Specific details on test material used for the study:
- Appearance: viscous solution (in 50% concentration)
- For use: diluted in water
Species:
guinea pig
Strain:
other: albino (not further specified)
Route:
intradermal
Vehicle:
water
Concentration / amount:
0.1%
Route:
intradermal
Vehicle:
water
Concentration / amount:
0.1%
No. of animals per dose:
5
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
0.1%
No. with + reactions:
4
Total no. in group:
5
Clinical observations:
4/5 animals showed very slight erythema, 3/5 animals very slight oedema. Reactions after challenge were not different from those during priming.

Table 1. Summary of dermal reactions

Injection no

Animal no.

1

2

3

4

5

erythema

oedema

erythema

oedema

erythema

oedema

erythema

oedema

erythema

oedema

1

0

0

0

0

1

0

1

1

1

1

2

1

2

1

1

1

1

2

2

1

1

3

1

1

1

1

0

1

1

1

1

1

4

1

0

1

1

0

0

1

0

0

0

5

1

0

0

1

0

0

0

0

0

0

6

1

0

0

1

0

0

0

0

1

0

7

1

1

1

1

0

1

0

0

1

1

8

1

1

0

0

1

1

0

0

1

0

9

1

1

1

0

0

1

1

0

1

1

10

1

0

0

1

1

1

2

1

1

1

Challenge

1

1

1

0

0

0

1

1

1

1

Conclusions:
Under the study conditions and although the number of animals tested was limited, the results of the present study do not indicate that the test substance at a concentration of 0.1% was a skin sensitiser. This concentration, however, did induce very slight to slight skin irritation reactions.
Executive summary:

A study was conducted to determine the skin sensitisation potential of the test substance in albino guinea pigs. Five test animals were used for the study. The concentration of the test substance for the induction and challenge phases were an intradermal induction with 10 injections of 0.1% in water every alternate intradermal and a challenge with 1 injection of 0.1% in water two weeks after the 10th induction injection. Very slight erythema and oedema were noted 24 h after challenge, but these reactions after challenge were not substantially different from those after the induction injections. Under the study conditions and although the number of test animals was limited, the test substance was considered as a non-sensitising to guinea pig skin (Anonymous, 1969).

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1968
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Principles of method if other than guideline:
The skin of 10 guinea pigs was clipped, and animals received 8 epicutaneous priming doses (0.15 mL first applied volume, other 7 applications 0.25 mL) of a 0.1% aqueous solution every other d in an area on the lower back site. Two weeks after the 8th application, a challenge application of 0.15 mL was given on the shoulder area. Skin readings were made 24h after the first application and 24h after the challenge application. The challenge reaction was compared with the first application.
GLP compliance:
no
Type of study:
open epicutaneous test
Justification for non-LLNA method:
The Local Lymph Node Assay (LLNA; TG 429) was adopted in 2002
Specific details on test material used for the study:
- Lot no.: 3119
- For use: diluted in water (0.1%)
Species:
guinea pig
Strain:
other: albino (not further specified)
Sex:
male
Route:
epicutaneous, open
Vehicle:
water
Concentration / amount:
0.1%
Route:
epicutaneous, open
Vehicle:
water
Concentration / amount:
0.1%
No. of animals per dose:
10
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
0.1%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
No reactions observed
Interpretation of results:
not sensitising
Conclusions:
Under the study conditions and although the number of animals tested was limited, the results of the present study did not indicate that the test substance at a concentration of 0.1% was a skin sensitiser. This concentration, however, did not induce skin irritation reactions.
Executive summary:

A study was performed to assess the skin sensitisation potential of the test substance in the albino guinea pig. Ten male test animals were used for the study. The concentration of the test substance for the induction and challenge phases were first an epicutaneous induction of 8 applications of 0.1% in water every day and then an epicutaneous challenge of 1 application of 0.1% in water two weeks after the 8th induction application. No skin reactions were noted 24 h after the first induction application and 24 h after challenge. Under the study conditions and although the number of test animals was limited, the test substance was considered as a non-sensitising to guinea pig skin (Hixson, 1968).

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
other: Literature data
Adequacy of study:
weight of evidence
Study period:
1996 and 1998
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
documentation insufficient for assessment
Qualifier:
according to
Guideline:
other:
Version / remarks:
Recently developed LLNA test for the screening for sensitisation and results from standard guinea pig tests (GMPT and Büehler)
Principles of method if other than guideline:
Recently developed LLNA test for the screening for sensitisation, results from standard guinea pig tests (GMPT and Büehler) were compared for various substances, including the test substance.
GLP compliance:
not specified
Type of study:
mouse local lymph node assay (LLNA)
Species:
mouse
Key result
Parameter:
SI
Remarks on result:
other: the stimulation index for test substance did not exceed the factor 3 and thus the outcome was considered negative
Conclusions:
Under the study conditions and based on the literature data of LLNA, the test substance was not considered to be a skin sensitiser.
Executive summary:

Studies were conducted to determine the skin sensitisation potential of the test substance. Basketter (1996) compared the results obtained with various substances, including the present test substance, in an LLNA assay, a guinea pig maximisation test (GMPT) and a Buehler test. Although the test substance was evaluated as non-sensitising in the guinea pig test, the LLNA result was positive. The LLNA test however, can give false positive results for strong irritants (as does the GPMT test), as was demonstrated by the non-sensitising irritant sodium dodecyl sulphate which was tested positive in the LLNA. In order to evaluate possible false-positive results, a range of non-sensitising irritant chemicals, including the test substance were tested in the LLNA. The stimulation index for the test substance did not exceed the factor 3 and thus the outcome was considered negative (Basketter, 1998). Under the study conditions and based on the literature data of LLNA, the test substance was not considered to be a skin sensitiser (Basketter, 1996 and 1998).

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

Study 1. A study was conducted to determine the skin sensitisation potential of the test substance according to OECD Guideline 406 and US EPA OPPTS 870.2600 (Buehler test), in compliance with GLP. The study was conducted in two phases, with induction and challenge exposures. To determine the highest non-irritating concentration (HNIC) for the challenge phase, a preliminary irritation study was performed with 8 guinea pigs. The concentrations used were 100, 75, 50, 25, 1.25, 1.0, 0.75, 0.25 and 0.10%. w/w in distilled water. After treatment, the application sites were evaluated and scored. During the induction phase of the main study, 0.4 mL of a 1% w/w mixture of the test substance in distilled water was applied to the left side of each animal, once per week for three weeks. Twenty-seven days after the first induction dose, 0.4 mL of a 0.25% w/w (HNIC) mixture of the test substance in distilled water was applied to a naïve site on the right side of each test animal for challenge exposure. Ten additional animals exposed with 0.25% w/w mixture of the test substance in distilled water served as naive control group in the challenge phase only. Approximately 24 and 48 h after each induction and challenge dose, the animals were scored for erythema. Very faint to faint erythema (0.5 to 1) was observed in all test animals during induction. None of the test animals exhibited a positive skin sensitisation response (score greater than 0.5) at 24 or 48 h after challenge. Under the test conditions, the test substance was determined to be non-sensitising when applied topically to albino Hartley guinea pigs (Durando, 2005).

Study 2. A study was conducted to determine the skin sensitisation potential of the test substance according to EU Method B.6 (modified Draize test). For the induction phase, 0.1 mL of 0.1% test substance in water was injected intradermally into the back of each six guinea pigs. This procedure was repeated every other day, using a different injection site on each occasion, until a total of nine injections had been given. Injection sites were examined 24 h after each injection and scored for erythema and oedema using the Draize scale. After a two week interval, a single challenge intradermal injection of the same concentration and volume was given as for induction. Injection sites were examined 24 h after this challenge dose as before for erythema and oedema. The effects were compared to those produced by the priming doses in order to determine whether sensitisation had been produced. The priming injections elicited very slight to well defined erythema, and very slight to slight oedema on all occasions. The challenge dose produced a well-defined erythema and very slight oedema in all occasions. However, the challenge doses did not produce any greater reaction in any animal. Under the study conditions, the test substance was not considered sensitizing to guinea pig skin (Thomas, 1974).

Study 3. A study was conducted to determine the skin sensitisation potential of the test substance according to the Magnusson and Kligman method (guinea pigs maximisation test). Female albino guinea pigs received on Day 1 an intracutaneous injection of 0.1 mL of 0.1% test substance in isotonic saline with Freund's complete adjuvant (1:1) on the shaved part of the flank (approximately 6 x 4 cm). On Day 7, animas were applied an epicutaneous occlusive application for 48 h with 0.3 mL of 0.1% test substance in ethylene glycol monomethylether, water, Tween 80 (180/180/40) v/v. Finally, on Day 21, guinea pigs were challenged epicutaneously (open application) with 0.05 mL of test substance in water at the shaved ventral side of the animal. The response was monitored after 24 and 48 h next to a control group of 10 animals. Concentrations were previously ascertained by both intracutaneous and epicutaneous applications to determine irritation potential in three animals at 24 and 48 h, respectively. In all cases non-irritating concentrations were chosen. At 24 h after challenge, 4/20 animals showed a positive response consisting of slight erythema. After 48 h, 2/20 animals showed a slight macular erythema. Under the conditions of this study, the test substance was negative for skin sensitization (Schallreuter, 1996).  

Study 4. A study was conducted to determine the skin sensitisation potential of the test substance in albino guinea pigs. Five test animals were used for the study. The concentration of the test substance for the induction and challenge phases were an intradermal induction with 10 injections of 0.1% in water every alternate intradermal and a challenge with 1 injection of 0.1% in water two weeks after the 10th induction injection. Very slight erythema and oedema were noted 24 h after challenge, but these reactions after challenge were not substantially different from those after the induction injections. Under the study conditions and although the number of test animals was limited, the test substance was considered as a non-sensitising to guinea pig skin (Anonymous, 1969).

Study 5. A study was performed to assess the skin sensitisation potential of the test substance in the albino guinea pig. Ten male test animals were used for the study. The concentration of the test substance for the induction and challenge phases were first an epicutaneous induction of 8 applications of 0.1% in water every day and then an epicutaneous challenge of 1 application of 0.1% in water two weeks after the 8th induction application. No skin reactions were noted 24 h after the first induction application and 24 h after challenge. Under the study conditions and although the number of test animals was limited, the test substance was considered as a non-sensitising to guinea pig skin (Hixson, 1968).

Study 6. Studies were conducted to determine the skin sensitisation potential of the test substance. Basketter (1996) compared the results obtained with various substances, including the present test substance, in an LLNA assay, a guinea pig maximisation test (GMPT) and a Buehler test. Although the test substance was evaluated as non-sensitising in the guinea pig test, the LLNA result was positive. The LLNA test however, can give false positive results for strong irritants (as does the GPMT test), as was demonstrated by the non-sensitising irritant sodium dodecyl sulphate which was tested positive in the LLNA. In order to evaluate possible false-positive results, a range of non-sensitising irritant chemicals, including the test substance were tested in the LLNA. The stimulation index for the test substance did not exceed the factor 3 and thus the outcome was considered negative (Basketter, 1998). Under the study conditions and based on the literature data of LLNA, the test substance was not considered to be a skin sensitiser (Basketter, 1996 and 1998).

Respiratory sensitisation

Link to relevant study records
Reference
Endpoint:
respiratory sensitisation
Data waiving:
other justification
Justification for data waiving:
other:
Reason / purpose:
data waiving: supporting information
Reason / purpose:
data waiving: supporting information
Reason / purpose:
data waiving: supporting information
Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

The available in vivo skin sensitisation studies suggest that the test substance is not a skin sensitiser and therefore no classification is required for this endpoint according to CLP (EC 1272/2008) criteria.