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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:
key study
Study period:
1983
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1983
Report Date:
1983

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 406 (Skin Sensitisation)
GLP compliance:
not specified
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
The in vivo study data were obtained in studies performed before any in vitro sensitization tests tests had been validated and accepted for regulatory purposes. Additionally, literature data demonstrates that an LLNA method is unreliable for surfactant substance, and may provide false positive results[1]. Therefore, an LLNA method is not deemed reliable for assessing the skin sensitisation of the substance.

[1]: Evaluating the sensitization potential of surfactants: Integrating data from the local lymph node assay, guinea pig maximization test, and in vitro methods in a weight-of-evidence approach. Ball et al. Regulatory Toxicology and Pharmacology 60 (2011) 389–400

Test material

Reference
Name:
Unnamed
Type:
Constituent

In vivo test system

Test animals

Species:
guinea pig
Strain:
other: Pirbright-White
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Age at study initiation: no data
- Weight at study initiation: 300 - 430 g
- Housing: max. 2 animals in one cage, Macrolon cages
- Diet: ad libitum; Ssniff-G (Alleindiät für Meerschweinchen), Ssniff Versuchstier-Diaten GmbH, 4770 Soest/Westfalen
- Water: ad libitum
- Acclimation period: 9 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 23
- Humidity (%): 40-70
- Air changes (per hr): 10 per hour
- Photoperiod: 12 hours daily

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal and epicutaneous
Vehicle:
water
Concentration / amount:
DOSE RANGE FINDING STUDY:
epicutaneous: 5%, 20%, 50%, 100%
intradermal: 0.1%, 0.5%, 1%, 5%

MAIN STUDY
Induction
intradermal: 5%
epicutaneous: 20%

Challenge
epicutaneous: 5%
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
DOSE RANGE FINDING STUDY:
epicutaneous: 5%, 20%, 50%, 100%
intradermal: 0.1%, 0.5%, 1%, 5%

MAIN STUDY
Induction
intradermal: 5%
epicutaneous: 20%

Challenge
epicutaneous: 5%
No. of animals per dose:
Range finding:
6 animals (4 epicutaneous, 2 intradermal)

Main Study:
10 animals (test group)
5 animals (control group)
Details on study design:
The test was performed according to a modified version of the Magnusson-Kligman Guinea Pig Maximisation Test. This investigation was performed according to HLD test plan P 3/152, 3-rd revision as well as according to the recommended guidelines of the USA Interagency Regulatory
Liaison Group (IRLG, January, 1981).

RANGE FINDING TESTS:
Four animals were treated dermally in a preliminary study under occlusiv conditions (exposure period 24 h) with the following concentrations of the sample: epicutaneous: 5%, 20%, 50%. Reading 3 h p.a.
Two animals were treated intradermal: 0.1%, 0.5%, 1%, 5% (aqueous solution). Reading 24 h p.a.

MAIN STUDY
A. INDUCTION EXPOSURE
A.1 INTRADERMAL INJECTION – Performed on Test Day 1
Based on the pretest results, the test item concentration of 5% was selected for intradermal induction in the main study.
An area of dorsal skin from the scapular region (approximately 6 x 8 cm) was clipped free of hair. Three pairs of intradermal injections (0.1 mL/site) were made just within the boundaries of a 4 x 6 cm area in the clipped region as follows:

- Test groups:
1. 0.1 ml Complete Adjuvant (50 % v/v in water for injection) (Bactoadjuvant Completa H 37 Ra, Difco Laboratories, Detroit, Michigan)
2. 0.1 ml 5 % v/v test substance in Aqua dest.
3. 0.1 ml 5 % v/v test substance in Aqua dest. emulsified in 50 % Adjuvant

- Control group:
1. 0.1 ml Complete Adjuvant (50 % v/v in water for injection)
2. 0.1 ml aqua dest
3. 0.1 ml Complete Adjuvant (50 % v/v in aqua dest.)

A.2 EPIDERMAL INDUCTION - Performed one week after intradermal injection
- Volume: 0.5 ml
- Exposure period: 48 h
- Test groups: 10
- Control group: 5
- Site: the same site as for intradermal injection
- Frequency of applications: 1
- Concentrations: 20%
B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 2 weeks after induction
- Exposure period: 24 h
- Control group: aqua dest.
- Concentrations: 5 %
- Evaluation (hr after challenge): 48h, 72h
Positive control substance(s):
not specified

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
48
Group:
test group
Dose level:
5 %
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
no skin reaction
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 48.0. Group: test group. Dose level: 5 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no skin reaction.
Reading:
2nd reading
Hours after challenge:
72
Group:
test group
Dose level:
5 %
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
no skin reaction
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 72.0. Group: test group. Dose level: 5 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no skin reaction.
Reading:
1st reading
Hours after challenge:
48
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
no skin reaction
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 0%. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: no skin reaction.
Reading:
2nd reading
Hours after challenge:
72
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
5
Clinical observations:
no skin reaction
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 72.0. Group: negative control. Dose level: 0%. No with. + reactions: 0.0. Total no. in groups: 5.0. Clinical observations: no skin reaction.

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Conclusions:
Since no allergic responses were observed in this MAXIMIZATION test, the test substance is not a dermal sensitizer.
Executive summary:

In a dermal sensitization study with the substance in water, young adult Pirbright-White guinea pigs (15 males;10 test and 5 control) were tested using the MAXIMIZATION test method equivalent to OECD Guideline 406.

The maximum compatible concentrations which led to slight irritation after intradermal and dermal application as well as the subirritative dose for the challenge application were determined in pretests. Water was used as vehicle during induction and challenge. Based on the results of the pretests, for the intradermal and epicutaneous induction exposure test substance concentrations of 5% and 20% were used, respectively. The test article concentration for the challenge application was 5%.

No allergic skin reactions were observed in test animals 48 and 72 hours after the challenge exposure. No findings were observed in control animals.

The sensitisation rate, i.e. the number of animals showing an allergic response expressed as a percentage of the total number of animals, was 0 %.

In this study, the substance is not a dermal sensitizer.