Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records
Reference
Endpoint:
skin sensitisation: in vivo (non-LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1993-09-27 to 1993-11-08
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP and guideline compliant study report.
Qualifier:
according to
Guideline:
EPA OTS 798.4100 (Skin Sensitisation)
Deviations:
no
GLP compliance:
yes
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
one other study available
Species:
guinea pig
Strain:
Hartley
Sex:
male
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Sasco Inc., Madison, WI, USA
- Weight at study initiation: 377-490 g
- Housing: Individually housed in stainless steel, wire mesh bottom cages
- Diet: ad libitum, Fresh Agway Certified Guinea Pig Feed
- Water: ad libitum, tap water
- Acclimation period: 11 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17.8 - 26.1
- Humidity (%): 40 - 70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12
Route:
intradermal and epicutaneous
Vehicle:
propylene glycol
Concentration / amount:
Induction I: 5 % (in propylene glycol)
Induction II: 100 %
Challenge: 100 %
Rechallenge: 100 %
Route:
epicutaneous, occlusive
Vehicle:
propylene glycol
Concentration / amount:
Induction I: 5 % (in propylene glycol)
Induction II: 100 %
Challenge: 100 %
Rechallenge: 100 %
No. of animals per dose:
20
Details on study design:
RANGE FINDING TESTS: Intradermal and Topical Range finding study
Four v/v dilutions of the test article were prepared in propylene glycol and administered to each of five guinea pigs. The dilutions used were 5 %, 4 %, 2 %, and 1 %. Two pair of intradermal injections at a volume of 0.1 mL each were made along the spine (two injections per side) above the scapular region so that each animal received one injection of each test article concentration. Approximately 24 and 48 hours after dosing, all sites were scored for erythema and edema according to the Draize scoring method.
Four v/v mixtures of the test article were prepared in propylene glycol and administered to each of five guinea pigs. The concentrations used were: Neat, 50 %, 25 % and 10 %. A dose of 0.5 mL of each concentration of the test article was applied to a one square inch gauze patch which was then placed on the skin of the flank region, two on each side of the dorsal midline. The patches were taped in place and the trunk of the animal was wrapped with a non-reactive, occlusive wrapping. Approximately 24 hours following patch application, all wrappings were removed and the skin wiped to remove any remaining test article. Approximately 24 and 48 hours after patch removal, all sites were scored for erythema and edema according to the Draize scoring method


MAIN STUDY
A. INTRADERMAL INDUCTION EXPOSURE
- No. of exposures: 6
- Test groups: 3 different injections were given:
1. 0.1 mL of a 1:1 Freund's Complete Adjuvant/sterile water, U.S.P., emulsion
2. 0.1 mL of test article
3. 0.1 mL of a 1:1 mixture of the test article and a 1:1 Freund's Complete Adjuvant/sterile water, U.S.P., emulsion
- Control group: 3 different injections were given:
1. 0.1 mL of 1:1 Freund's Complete Adjuvant/sterile water, U.S.P., emulsion
2. 0.1 mL of propylene glycol
3. 0.1 mL of a 1:1 mixture of propylene glycol and a 1:1 Freund's Complete Adjuvant/sterile water, U.S.P., emulsion
- Site: one row of three injections on each side of the animals midline above the intrascapular region
- Frequency of applications: once
- Duration: 8 days
- Concentrations: 5 % of test substance in propylene glycol

B. TOPICAL INDUCTION EXPOSURE
- No. of exposures: 1
- Exposure period: 48 hours
- Test groups: topically dosed with a 2 x 4 cm patch of Whatman No. 3 mm filter paper saturated with neat test article
- Control group: topically dosed with a 2 x 4 cm patch of Whatman No. 3 mm filter paper saturated with propylene glycol.
- Site: animals midline above the scapular region
- Frequency of applications: once
- Duration: 48 hours
- Concentrations: 100 % of test substance

C. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 16 days after topical induction
- Exposure period: 24 hours
- Test groups: topically dosed with 0.4 mL of neat test substance
- Control group: topically dosed with 0.4 mL of neat test substance
- Site: flank
- Concentrations: 100 %
- Evaluation (hr after challenge): 24, 48 hours after patch removal

D. RECHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: Seven days after challenge
- Exposure period: 24 hours
- Test groups: topically dosed with 0.4 mL of neat test substance
- Control group: topically dosed with 0.4 mL of neat test substance
- Site: flank
- Concentrations: 100 %
- Evaluation (hr after rechallenge): 24, 48 hours after patch removal
Positive control substance(s):
yes
Remarks:
Dinitrochlorobenzene (DNCB)
Positive control results:
Positive controls with DNCB demonstrated a 100 % positive response.
Reading:
1st reading
Hours after challenge:
24
Group:
test group
Dose level:
100 %
No. with + reactions:
1
Total no. in group:
20
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 100 %. No with. + reactions: 1.0. Total no. in groups: 20.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
test group
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 20.0.
Reading:
1st reading
Hours after challenge:
24
Group:
negative control
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
negative control
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
rechallenge
Hours after challenge:
24
Group:
test group
Dose level:
100 %
No. with + reactions:
1
Total no. in group:
20
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 100 %. No with. + reactions: 1.0. Total no. in groups: 20.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
test group
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
20
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 20.0.
Reading:
rechallenge
Hours after challenge:
24
Group:
negative control
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
rechallenge
Hours after challenge:
48
Group:
negative control
Dose level:
100 %
No. with + reactions:
0
Total no. in group:
10
Remarks on result:
other: Reading: rechallenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 10.0.
Reading:
1st reading
Hours after challenge:
24
Group:
positive control
Dose level:
0.1 %
No. with + reactions:
5
Total no. in group:
5
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: positive control. Dose level: 0.1 %. No with. + reactions: 5.0. Total no. in groups: 5.0.
Reading:
2nd reading
Hours after challenge:
48
Group:
positive control
Dose level:
0.1 %
No. with + reactions:
5
Total no. in group:
5
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: positive control. Dose level: 0.1 %. No with. + reactions: 5.0. Total no. in groups: 5.0.

During the intradermal range finding phase, the 5 %, 4 %, 2 %, and 1 % applications of test article produced irritation at both the 24 and 48 hour scoring periods. Since no significant difference in the degree and extent of irritation was observed between any of the concentrations used, the test article was administered as a 5 % concentration in propylene glycol at induction I. During topical range finding phase, the Neat, 50 %, 25 % and 10 % of test article in propylene glycol produced no dermal irritation at either the 24 or 48 hour scoring periods. Based on these results, the test article was administered neat at induction II and challenge. At challenge, one of the twenty animals (5 %) in the test article induction/challenge/rechallenge group exhibited dermal response at the 24 hour scoring period and none of the animals exhibited response at the 48 hour scoring period. None of the corresponding challenge irritation control group animals exhibited dermal irritation at either the 24 hour or 48 hour scoring period. In the DNCB positive control group, 100 % of the induction/challenge animals had scores greater than the scores observed in the DNCB challenge irritation control group at both the 24 and 48 hour scoring periods. To confirm the dermal response exhibited by the single test article induction/challenge/rechallenge group animal at challenge, the Sponsor elected to proceed with a rechallenge. During the rechallenge phase, the test article was topically administered neat to the test article induction/challenge/rechallenge and rechallenge irritation control group animals. At rechallenge, one of the twenty animals (5%) in the test article induction/challenge/rechallenge group (the same animal that exhibited a response at challenge) exhibited dermal response at the 24 hour scoring period and none of the animals exhibited dermal response at the 48 hour scoring period. None of the ten corresponding rechallenge irritation control group animals exhibited dermal irritation at either the 24 or 48 hour scoring periods.

Interpretation of results:
not sensitising
Remarks:
Migrated information
Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

In a dermal sensitisation study according to EPA OTS 798.4100 with the test substance, young adult, male Hartley guinea pigs were tested using the guinea pig maximisation test (GPMT). The shaved skin of twenty animals was treated with the test substance by intradermal injection (as a 5% solution in propylene glycol vehicle with and without Freund´s adjuvant) and then topical application (neat liquid test substance) eight days later. Sixteen days after the second induction administration, animals were challenged with 0.4 mL of neat substance using a 24 hour occlusive dermal exposure. The dose level for challenge was based on a topical dose range finding study to select the highest non-irritating dose and, in this study, no irritation was observed at concentrations of 10, 25, 50 or 100 % in petrolatum. The non-induced animals were also challenged with the same concentration of test material and served as controls. The site of exposure was examined for erythema and edema 24 and 48 hours following removal of the test substance. Because one animal showed a response and because challenge was delayed, a rechallenge was conducted one week later with identical concentrations of test substance. At challenge, 1/20 test animals were scored positive after 24 hour evaluation (mean severity 0.05) and 0/20 were scored positive at the 48 hour examination. No negative control animals responded. At rechallenge 1/20 test animals (the same animal) were scored positive at the 24 hours evaluation (mean severity 0.1) and no animals were scored positive at the 48 hour examination. Negative controls did not show any response. The positive controls demonstrated a 100 % response (mean 24 hour severity 6.6/8; mean 48 hour severity (5.0/8)

The substance was not found to be a skin sensitiser in this study.


Migrated from Short description of key information:
The test substance is not sensitising according to the guinea pig maximization test (Hoechst-Celanese, 1994)

Justification for selection of skin sensitisation endpoint:
GLP and guideline compliant study report.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance does not need to be classified and labelled as skin sensitising under Regulation (EC) No 1272/2008, as amended for the seventh time in Regulation (EU) No 2015/1221.