2-methyl-2-nitropropan-1-ol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Remarks:

Method according to Buehler

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPP 81-6 (Skin Sensitisation)

Principles of method if other than guideline:

The sensitization potential of test material was tested in the female guinea pig according to Buehler's procedure (Buehler, E.V. "Delayed Contact Hypersensitivity in the Guinea Pig", Arch. Dermat. 91, 171-175, 1965)

GLP compliance:

no

Type of study:

Buehler test

Justification for non-LLNA method:

Buehler test considered to be reliable predictor of dermal sensitization

Test material

Test material information

Constituent 1

Reference substance name:

2-methyl-2-nitropropan-1-ol

EC Number:

200-957-6

EC Name:

2-methyl-2-nitropropan-1-ol

Cas Number:

76-39-1

Molecular formula:

C4H9NO3

IUPAC Name:

2-methyl-2-nitropropan-1-ol

Details on test material:

Purity is above 99%.

Specific details on test material used for the study:

NMP Crystals, 2-nitro-2-methyl-1-propanol, 99.6% purity

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

female

Details on test animals and environmental conditions:

Test conducted with 30 female guinea pigs weighing 250-300 g. Group 1: ten animals treated with test material; Group 2: ten animals treated wirh positive control; Group 3: ten animals treated with negative control

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

Distilled water

Concentration / amount:

Group 1: 0.5 ml of 25% test material

Day(s)/duration:

1 day (24 hours)

Adequacy of induction:

not specified

Induction 2

Route:

epicutaneous, occlusive

Vehicle:

not specified

Remarks:

5% Formaldehyde

Concentration / amount:

Group 2: 0.5 ml of 5% formaldehyde

Day(s)/duration:

1 (24 Hours)

Adequacy of induction:

not specified

Induction 3

Route:

epicutaneous, occlusive

Vehicle:

not specified

Remarks:

1% CMC

Concentration / amount:

0.5 ml of 1% CMC

Day(s)/duration:

1 (24 Hours)

Adequacy of induction:

not specified

Challenge

Challenge 1

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

Distilled water

Concentration / amount:

0.5 ml

Day(s)/duration:

1 day

Adequacy of challenge:

not specified

Challenge 2

No.:

#2

Route:

epicutaneous, occlusive

Vehicle:

not specified

Remarks:

5% formaldehyde

Concentration / amount:

0.5 ml

Day(s)/duration:

1 day

Adequacy of challenge:

not specified

Challenge 3

No.:

#3

Route:

epicutaneous, occlusive

Vehicle:

not specified

Remarks:

1% CMC

Concentration / amount:

0.5 ml

Day(s)/duration:

1 day

Adequacy of challenge:

not specified

No. of animals per dose:

10 animals per group

Details on study design:

Thirty female guinea pigs weighing 250-300 g were divided into 3 groups of ten each. The animals' backs and flanks were shaved free of hair. Group 1 was treated topically with 0.5 ml of 25% test material solution in distilled water under an occulsiove patch for 24 hours. Group 2 (positive control) was similarly treated with 0.5 ml of 5% formaldehyde solution. Group 3 (negative control) was treated in the same way with 0.5 ml 1% carboxymethyl cellulose (CMC) suspension. After 24 hours the patches were removed and the sites cleaned. This procedure was repeated for each group once a week for three weeks. After the last application animals were allowed to rest for two weeks. On the first day of the third week each group of animals was challenged topically with 0.5 ml of their respective solution. In additiona the Group 3 animals were also challenged with the test material solution and the formaldehyde solution. After 24 hours of exposure the patches were removed and the sites cleaned. The animals were allowed to rest for another 24 hours and then the challennge sites were depliated with Neet. Three hours later the challenge sites were scored for inglammatory skin reactions (edema and erythema). The material is considered a sensitizer if the scores in the treatment group are greater than those of the negactive controls. The positive control group serves as an internal control for the test.

Challenge controls:

Positive control was 2% formaldehyde; negative control was 1% CMC

Positive control substance(s):

yes

Remarks:

5% formaldehyde solution

Results and discussion

Positive control results:

Sixty percent of the positive control group showed skin reactions with 2% formaldehyde solution, an expected positive response

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

other: One reading following challenge

Hours after challenge:

3

Group:

test chemical

Dose level:

0.5 ml

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

None

Remarks on result:

no indication of skin sensitisation

Results 2

Key result

Reading:

other: One reading after challenge

Hours after challenge:

3

Group:

positive control

Dose level:

0.5 ml

No. with + reactions:

6

Total no. in group:

10

Remarks on result:

positive indication of skin sensitisation

Results 3

Key result

Reading:

other: One reading after challenge

Hours after challenge:

3

Group:

negative control

Dose level:

0.5 ml

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

no indication of skin sensitisation