α,α,α',α'-tetramethylxylene-α,α-diol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 June 2011 - 22 July 2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study has some deviations and the information in the report is limited.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: The Guidelines for the Testing of Chemicals (State Environmental Protection Administration of China, 2004.5, 406, Skin Sensitization Test)

Deviations:

no

GLP compliance:

no

Remarks:

The laboratory has no GLP accreditation (nevertheless the project plan and the report were audited by the Quality Assurance Unit)

Type of study:

Buehler test

Justification for non-LLNA method:

This study was performed for the Chinese regulatory authorities

Test material

Test material information

Constituent 1

Reference substance name:

α,α,α',α'-tetramethyl-m-xylene-α,α'-diol

EC Number:

217-886-1

EC Name:

α,α,α',α'-tetramethyl-m-xylene-α,α'-diol

Cas Number:

1999-85-5

Molecular formula:

C12H18O2

IUPAC Name:

2,2'-(1,3-phenylene)dipropan-2-ol

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

male

Details on test animals and environmental conditions:

TEST ANIMALS
- Source:
- Age at study initiation:
- Weight at study initiation:
- Housing:
- Diet and water: ad libitum except during exposure
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-23
- Humidity (%): 40-70
- Air changes (per hr): 12
- Photoperiod (hrs dark / hrs light): 12

Study design: in vivo (non-LLNA)

Induction

Route:

epicutaneous, semiocclusive

Vehicle:

water

Concentration / amount:

0.2g / 100%

Day(s)/duration:

Days 0, 7 and 14

Adequacy of induction:

highest technically applicable concentration used

Challenge

Challenge 1

Route:

epicutaneous, semiocclusive

Vehicle:

water

Concentration / amount:

0.1 g /100%

Day(s)/duration:

Day 28

Adequacy of challenge:

highest non-irritant concentration

Challenge 2

Concentration / amount:

100% (0.2g)

No. of animals per dose:

15

Details on study design:

The test substance was pre-moistened with distilled water.

Positive control substance(s):

yes

Remarks:

dinitrochlorobenzene

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100% (0.1g)

No. with + reactions:

0

Total no. in group:

15

Clinical observations:

none

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100% (0.1g)

No. with + reactions:

0

Total no. in group:

15

Clinical observations:

none

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

100% (0.1g)

No. with + reactions:

0

Total no. in group:

15

Clinical observations:

none

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

100% (0.1g)

No. with + reactions:

0

Total no. in group:

15

Clinical observations:

none

Results 5

Reading:

1st reading

Hours after challenge:

24

Group:

positive control

Dose level:

2,4-dinitrochlorobenzene mixed in vaselinum was 1.25 mg/g (the amount was 0.2 g).

No. with + reactions:

10

Total no. in group:

15

Clinical observations:

none

Results 6

Reading:

2nd reading

Hours after challenge:

48

Group:

positive control

Dose level:

2,4-dinitrochlorobenzene mixed in vaselinum ( the amount was 0.2 g)

No. with + reactions:

10

Total no. in group:

15

Clinical observations:

none

Any other information on results incl. tables

All animals appeared active and healthy. There were no signs of gross toxicity, adverse pharmacology effects or abnormal behavior. No gross pathological changes were observed at necropsy.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

No skin reactions were observed in the test group. Based on the results of this study the substance would not be regarded as a skin sensitizer.

Executive summary:

The delayed contact hypersensivity of the meta-diols was evaluated in Guinea pigs according to OECD N°406 guideline (Buehler test).

On day 0, 7 and 14, the test and positive control group animals were given induction exposure; the negative control animals were not treated. On day 28, all the three groups were given challenge exposure on the opposite intact skin. Skin reactions were scored at 24 and 48 hours after completion of the challenge application.

Positive reactions were not observed in the test group animals at the 24-hour and 48-hour examination; the sensitization rate was 0%. Erythema occurred in 10 animals in the positive control group; the sensitization rate was 66.7%. There were no positive skin responses in the negative control group; the sensitization rate was 0%. There was no mortality, and there were no remarkable clinical observations in any group.

In conclusion, under these experimental conditions, meta-diols was considered as non-sensitizing in the Buehler test.