Registration Dossier

Diss Factsheets

Toxicological information

Skin sensitisation

Currently viewing:

Administrative data

Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
From 2000-03-14 to 2000-04-07
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Study performed according to OECD test guideline No. 406 and in compliance with GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report date:
2000

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Version / remarks:
17 July 1992
Deviations:
no
Principles of method if other than guideline:
not applicable
GLP compliance:
yes
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
At the time of study performance, the LLNA method was not adopted.

Test material

Constituent 1
Chemical structure
Reference substance name:
(5E)-3-Methyl-5-cyclopentadecen-1-one
Cas Number:
101151-17-1
Molecular formula:
C16 H28 O
IUPAC Name:
(5E)-3-Methyl-5-cyclopentadecen-1-one
Constituent 2
Chemical structure
Reference substance name:
(5Z)-3-Methyl-5-cyclopentadecen-1-one
Cas Number:
21944-94-5
Molecular formula:
C16 H28 O
IUPAC Name:
(5Z)-3-Methyl-5-cyclopentadecen-1-one
Constituent 3
Chemical structure
Reference substance name:
(4E)-3-Methyl-4-cyclopentadecen-1-one
Cas Number:
62221-84-5
Molecular formula:
C16 H28 O
IUPAC Name:
(4E)-3-Methyl-4-cyclopentadecen-1-one
Test material form:
liquid
Details on test material:
- Physical state: Liquid
- Storage conditions: stored at ambient room temperature

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Davidson's Mill Farms, South Brunswick, NJ
- Age at study initiation: young adults
- Weight at study initiation: M: 390-505 g; F: 381-486 g
- Housing: group housed in suspended stainless steel caging with mesh floors
- Diet (e.g. ad libitum): Pelleted Purina Guinea Pig Chow #5025 ad libitum
- Water (e.g. ad libitum): Filtered tap water ad libitum
- Acclimation period: 18 days
- Indication of any skin lesions: No skin lesion identified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22 °C
- Humidity (%): 36-70 %
- Air changes (per hr): no data
- Photoperiod: 12 hrs dark / 12 hrs light

IN-LIFE DATES: From: 2000-25-02 To: 2000-04-07

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
intradermal
Vehicle:
other: mineral oil
Concentration / amount:
40% w/v
Day(s)/duration:
Day 0
Adequacy of induction:
highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically
Route:
epicutaneous, semiocclusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
100 %
Day(s)/duration:
Day 7 / 48 hours
Adequacy of induction:
non-irritant substance, but skin pre-treated with 10% SDS
Challenge
No.:
#1
Route:
epicutaneous, occlusive
Vehicle:
unchanged (no vehicle)
Concentration / amount:
100 %
Day(s)/duration:
Day 21 / 24 hours
Adequacy of challenge:
highest non-irritant concentration
No. of animals per dose:
17 preliminary test animals, 20 test animals, 10 control animals
Details on study design:
RANGE FINDING TESTS:
- Intradermal injections: 50%, 40%, 30%, 20%, 10%, 5%, 4%, 3%, 2%, 1%, 0.5% and 0.1% w/w in 70/30 DEP/ETOH. 6 test sites/guinea-pig, 4 guinea-pigs. Due to severe irritation noted for all sites, 2 additional animals were injected with just the vehicle and exhibited the same severe response. One animal was used to evaluate the possible alternatives with propylene and mineral oil. Mineral oil was chosen for the intradermal injections to yield concentrations of 50%, 40%, 30%, 20%, 10% and 5%. The concentration which produced mild to moderate irritation was 40%.
- Topical induction: 100%, 75%, 50%, 25% w/w in 70/30 DEP/ETOH. 4 test sites/guinea-pig, 4 guinea-pigs. The concentration which produced mild to moderate irritation was 100%.
- Topical challenge: 100%, 75%, 50%, 25% w/w in 70/30 DEP/ETOH. 4 test sites/guinea-pig, 4 guinea-pigs. The highest concentration that produced responses in 4 guinea-pigs no more severe than 2 scores of 0.5 and 2 scores of 0 was 100%.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2, intradermal injections and topical application
- Exposure period: 48h for topical application
- Test groups:
INTRADERMAL: 3 pairs of intradermal injection (0.1 mL) in the shaved anterior shoulder on Day 0 after shaving as follows:
- 1/ 50% FCA
- 2/ test substance 40% in mineral oil
- 3/ test substance 40% in 50% FCA
SODIUM LAUREL SULFATE: As the substance is not a skin irritant, 24 hours prior to the topical application, the shoulder area was pre-treated with 5 %SLS mixture in petrolatum. Prior to the topical induction, the test sites were gently wiped with ethanol then water.
TOPICAL: 7 days after intradermal injections, 0.8 mL of the test substance (100%) was applied and covered with a gauze patch secured in place and wrapped with non-allergenic Durapore adhesive tape (semi-occlusive tape). After the 48 hour exposure period, the patches were removed and the test sites were wiped gently with DEP/ETOH then water, using a clean towel to remove any residual substance.
- Control group: similarly treated with the exception that the test substance was omitted.
- Evaluation (hr after challenge): approximately 24 and 48 hours after patch removal.

B. CHALLENGE EXPOSURE
- No. of exposures:
- Day(s) of challenge: 21 days after test initiation
- Exposure period: 24 hours
- Test groups: 0.4 mL of the test substance was applied using an occlusive 25 mm Hilltop Chamber®. The chambers were secured in place and wrapped with non-allergenic Durapore adhesive tape. After the 24 hours exposure period, the chambers were removed and the sites were gently wiped with DEP/ETOH then water, using a clean towel to remove any residual substance.
- Control group: similarly treated with the exception that the test substance was omitted
- Site: right side
- Concentrations: 100%
- Evaluation (hr after challenge): approximately 24 and 48 hours after patch removal.
Challenge controls:
None
Positive control substance(s):
yes
Remarks:
HCA (at least 85-91.7% pure), as an historical positive control

Results and discussion

Positive control results:
INDUCTION PHASE: Severe erythema (3) was noted at all positive control sites during the topical induction phase.
CHALLENGE PHASE: All ten positive control animals exhibited signs of a sensitisation response (faint to severe erythema[1-3]) 24 hours after challenge. Similar indications persisted in 4 animals through 48 hours

In vivo (non-LLNA)

Resultsopen allclose all
Key result
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
100%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
Very faint erythema (0.5) was noted in 8/20 animals
Remarks on result:
no indication of skin sensitisation
Key result
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
Irritation (grade 0.5) persisted in 5/20 animals
Remarks on result:
no indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
25 %
No. with + reactions:
10
Total no. in group:
10
Clinical observations:
faint to severe erythema[1-3]
Remarks on result:
positive indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
25 %
No. with + reactions:
4
Total no. in group:
10
Remarks on result:
positive indication of skin sensitisation
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
very faint erythema (0.5) was noted in 5/10 animals
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
0%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
Irritation (grade 0.5) persisted in 4/10 animals
Remarks on result:
no indication of skin sensitisation

Any other information on results incl. tables

Topical induction phases:

- Test animals (100% test substance): very faint to faint erythema (0.5 -1) in 9/20 animals 24 hours after removal of patch. Very faint erythema (0.5) persisted in 6/20 through 48 hours.

- Negative controls: very faint to faint erythema (0.5 -1) in 6/10 animals 24 hours after removal of patch. Very faint erythema (0.5) persisted in 4/10 through 48 hours.

- Positive control (100% HCA): Severe erythema (3) was noted at all positive control sites

Applicant's summary and conclusion

Interpretation of results:
GHS criteria not met
Conclusions:
Under the test conditions, ST 19 C 99 is not classified according to the Regulation EC No. 1272/2008 (CLP) and to the GHS.
Executive summary:

In a dermal sensitisation study performed according to the EU test method B.6 and in compliance with GLP, ST 19 C 99 was tested in female Hartley guinea-pigs using the Guinea-Pig Maximisation Test method (20 treated animals + 10 controls).

The preliminary study determined the concentration which produced mild to moderate irritation to be used for the intradermal induction (40%) and for the topical induction (100%). 100% was selected as the highest non-irritant test substance concentration for the challenge.

 

ST 19 C 99 diluted in mineral oil at 40% (w/w) was administered by injection for intradermal induction. As the substance was not a skin irritant, 24 hours prior to the topical application, the site was pre-treated with 5% w/w sodium laurel sulphate in petrolatum. Topical induction was performed with ST 19 C 99 as supplied, 7 days after intradermal injections. For the challenge, ST 19 C 99 was tested at 100%.

 

The sensitivity of the guinea-pig is checked periodically at Product Safety Labs with HCA, a known sensitizer.

 

ST 19 C 99 did not produce evidence of skin sensitization during the study.

Under the test conditions, ST 19 C 99 is not classified according to the Regulation EC No. 1272/2008 (CLP) and to the GHS.

This study is considered as acceptable and satisfies the requirement for sensitisation endpoint.