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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)
Rationale for reliability incl. deficiencies:
other: Comparable to guideline study with acceptable restrictions.

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
1979
Report date:
1979
Reference Type:
study report
Title:
Unnamed
Year:
1979
Report date:
1979

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 406 (Skin Sensitisation)
Deviations:
yes
Remarks:
Induction phase comprised 1st and 2nd induction, each subdivided into intradermal and epidermal treatment with 1-week-intervals between each treatment.
Principles of method if other than guideline:
Study was performed as modification of the Magnusson-Kligman test before the actual guideline was adopted.
GLP compliance:
no
Type of study:
guinea pig maximisation test
Justification for non-LLNA method:
The study was conducted prior to the development and adoption of the LLNA Test guideline

Test material

Constituent 1
Reference substance name:
Methanol
EC Number:
200-659-6
EC Name:
Methanol
Cas Number:
67-56-1
Molecular formula:
CH4O
IUPAC Name:
methanol
Details on test material:
- Name of test material (as cited in study report): methanol, substance no. 78/333
- Analytical purity: no data

In vivo test system

Test animals

Species:
guinea pig
Strain:
other: Pirbright White
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Firma Hagemann, Lippische Versuchstierzucht, 4923 Extertal
- Weight at study initiation: 449 - 824 g
- Diet (e.g. ad libitum): Ssniff K, ad libitum
- Water (e.g. ad libitum): ad libitum

Study design: in vivo (non-LLNA)

Induction
Route:
intradermal and epicutaneous
Vehicle:
water
Concentration / amount:
50%
Challenge
Route:
epicutaneous, occlusive
Vehicle:
water
Concentration / amount:
50%
No. of animals per dose:
1st study: 10 test, 5 control
2nd study: 12 test, 5 control
Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 4
- Exposure period: d 0 (1st intradermal), 7 (1st epicutaneous), 14 (2nd intradermal), 21 ( 2nd epicutaneous)
- Test groups: 1st intradermal: 6 parallel injections with Freund's adjuvant, 50% methanol and Freund's adjuvant + 50% methanol, respectively; 2nd intradermal: 4 parallel injections with 50% methanol and Freund's adjuvant + 50% methanol, respectively; both epidermal: conc. methanol
- Control group: no induction treatment
- Site: shoulder region
- Frequency of applications: weekly
- Duration: epicutaneous: 48 h occlusive
- Concentrations: 50% intradermal, 100% epicutaneous


B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 34 days after 1st intradermal induction
- Exposure period: 24 h occlusive
- Test groups: 1st study: right 50% methanol, left 25% formaldehyde epicutaneous; 2nd study: concentrated methanol epicutaneous
- Control group: 1st study: right 50% methanol, left 25% formaldehyde epicutaneous; 2nd study: concentrated methanol epicutaneous
- Site: flank
- Concentrations: 50% methanol and 25% formaldehyde, respectively (study 1), 100% methanol (study 2)
- Evaluation (hr after challenge): 24, 48 and 72 hours
Challenge controls:
Control groups (no induction treatment)
Positive control substance(s):
no

Results and discussion

Positive control results:
Positive controls not performed.

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
other: 1st reading; 1st group
Hours after challenge:
24
Group:
test chemical
Dose level:
50%
No. with + reactions:
3
Total no. in group:
10
Clinical observations:
slight erythema (score 1)
Reading:
other: 2nd reading ; 1st group
Hours after challenge:
48
Group:
test chemical
Dose level:
50%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
none
Reading:
other: 3rd reading; 1st group
Hours after challenge:
72
Group:
test chemical
Dose level:
50%
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
none
Remarks on result:
no indication of skin sensitisation
Reading:
other: 1st reading; 2nd group
Hours after challenge:
24
Group:
test chemical
Dose level:
50%
No. with + reactions:
1
Total no. in group:
12
Clinical observations:
slight erythema (score 1)
Reading:
other: 2nd reading; 2nd group
Hours after challenge:
48
Group:
test chemical
Dose level:
50%
No. with + reactions:
1
Total no. in group:
12
Clinical observations:
slight erythemy (score 1)
Reading:
other: 3rd reading; 2nd group
Hours after challenge:
72
Group:
test chemical
Dose level:
50%
No. with + reactions:
0
Total no. in group:
12
Clinical observations:
none
Remarks on result:
no indication of skin sensitisation
Reading:
other: negative control
Hours after challenge:
24
Group:
negative control
Dose level:
100% water
No. with + reactions:
0
Total no. in group:
5
Remarks on result:
no indication of skin sensitisation
Reading:
other: positive control
Hours after challenge:
24
Group:
positive control
Dose level:
nil
No. with + reactions:
0
Total no. in group:
0
Remarks on result:
not measured/tested

Any other information on results incl. tables

In the first study, 3/10 females exhibited a slight skin response (erythema score 1) 24 h after challenge, in the parallel test with formaldehyde 1/10 females exhibited a slight skin response (erythema score 1) 24 h after challenge, which can be interpreted as weak sensitizing potential.

In the second study using 12 female animals at a concentration of 50 % methanol, 1/12 exhibited a slight skin response (erythema score 1) 24 and 48 h after challenge which can be interpreted as a weak sensitising potential.

The intracutane inductions produced necroses and some open ulcerations in both studies.

In summary, the low number of 4/22 animals with slight erythema (score 1) gives no evidence of a notable sensitisation potential of methanol.

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information