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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
Reliability:
2 (reliable with restrictions)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1993
Report date:
1993

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
GLP compliance:
not specified
Type of study:
Buehler test
Justification for non-LLNA method:
Study was performed before LLNA was formally validated and available as OECD guideline in 2002.

Test material

Constituent 1
Chemical structure
Reference substance name:
Tetrahydro-4-methyl-2-(2-methylprop-1-enyl)pyran
EC Number:
240-457-5
EC Name:
Tetrahydro-4-methyl-2-(2-methylprop-1-enyl)pyran
Cas Number:
16409-43-1
Molecular formula:
C10H18O
IUPAC Name:
tetrahydro-4-methyl-2-(2-methylprop-1-enyl)pyran

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Sprague Dawley, lnc.
- Weight at study initiation: 344-532 g
- housing: individually
- Acclimation period: at least 4 days
- Diet: ad libitum
- Water: ad libitum


ENVIRONMENTAL CONDITIONS
- Photoperiod (hrs dark / hrs light): 12-hour light/12-hour dark cycle.

Study design: in vivo (non-LLNA)

Inductionopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: diethyl phthalate (DEP)
Concentration / amount:
50% for induction
0.5%, 1.5% and 5% for challenge
Challengeopen allclose all
Route:
epicutaneous, occlusive
Vehicle:
other: diethyl phthalate (DEP)
Concentration / amount:
50% for induction
0.5%, 1.5% and 5% for challenge
No. of animals per dose:
20 (10/sex) for treated group
10 (5/sex) for control group
Details on study design:
RANGE FINDING TESTS:
Irritation was evaluated before a delayed hypersensitivity study in guinea pigs. A 0.3 ml aliquot of tetrahydro-4-methyl-2-(2-methylpropen-1-yl)pyran at concentrations of 0.5%, 1%, 2.5%, 5%, 10%, 25% and 50% in diethyl phthalate and undiluted substance were applied to the clipped back for 6 hours under occlusion using 25 mm Hill Top Chambers®. Reactions were scored 24 and 48h after application. 4 animals per sex were tested.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: 6 hours
- Site: shoulder
- Frequency of applications: once a week
- Duration: 3 weeks
- Concentrations: 50%
- Control group: not treated

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: approx. 2 weeks after last induction
- Site: untreated shoulder
- Concentrations: 0.5%, 1.5% and 5%
- Evaluation (hr after challenge): approx. 24 hours and 48 hours
Positive control substance(s):
yes
Remarks:
Historical positive control data generated February 20 and 21 1992 using 1-Chloro-2,4-Dinitrobenzene (DNCB)

Results and discussion

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
+/- reactions were observed in 1 animal
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 0.5%. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: +/- reactions were observed in 1 animal.
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
0.5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
no effects
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0.5%. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: no effects.
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
1.5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
no effects
Remarks on result:
other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 1.5%. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: no effects.
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
1.5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
+/- reactions were observed in 2 animals
Remarks on result:
other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 1.5%. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: +/- reactions were observed in 2 animals.
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
no effects
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 effects.
Reading:
2nd reading
Hours after challenge:
48
Group:
test chemical
Dose level:
5%
No. with + reactions:
0
Total no. in group:
20
Clinical observations:
no effects
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 effects.

Any other information on results incl. tables

Results Range Finding Test:

Slight or patchy erythema (score +/-) was found at all concentrations tested.

Slight or patchy erythema (score +/-) at time point 24h and 48h was found at 2.5% test substance and higher concentrations.

Slight or patchy erythema (score +/-) at time point 24h and 48h in 3/4 animals was found at 10%, 25% and 50% test substance.

Grade 1 erythema was observed in 1/4 animals at 50% test substance.

Undiluted material produced grade 1 erythema in 3/4 animals.

Challenge controls:

Slight or patchy erythema (score +/-) was found at time point 24h in 1/10 animals at 5% test substance.

Applicant's summary and conclusion