2-(isopropylthio)-3-(2,2,2-trifluoroethoxy)pyridine

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline and GLP compliant study with good documentation.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

2-(isopropylthio)-3-(2,2,2-trifluoroethoxy)pyridine

EC Number:

696-441-7

Cas Number:

256473-05-9

Molecular formula:

C10H12F3NOS

IUPAC Name:

2-(isopropylthio)-3-(2,2,2-trifluoroethoxy)pyridine

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Ibn: GOHI; SPF-quality guinea pigs (synonym: Himalayan spotted)

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source:RCC Ltd.; Biotechnology & Animal Breeding Division; 4414 Füllingsdorf; Switzerland
- Age at study initiation: 5-7 weeks
- Weight at study initiation: The weight at the start of the one week acclimation period was 289-387 g (males) and 317 - 360 g (females).
- Housing: individually at standard laboratory conditions.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 22°C
- Humidity (%): 52 - 75.5%
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12
- Music was played during the light period.

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

unchanged (no vehicle)

Induction 2

Concentration / amount:

5 % for intradermal induction
100% for epidermal induction (highest attainable concentration)
100 % for epidermal challenge (highest attainable concentration and highest non-irritating concentration)

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Challenge 2

Concentration / amount:

5 % for intradermal induction
100% for epidermal induction (highest attainable concentration)
100 % for epidermal challenge (highest attainable concentration and highest non-irritating concentration)

No. of animals per dose:

5 males and 5 females (control group)
10 males and 10 females (test group)

Details on study design:

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2
- Exposure period: intradermal, epidermal application: 48 h
- Test groups: test item in Freuds Complete Adjuvant (FCA) and in vehicle.
- Control group: FCA
- Site: left flanks
- Frequency of applications: intradermal injections Day 1, SLS treatment Day 7, epidermal applications Day 8
- Duration: epidermal: 48 h
- Concentrations: 5 % intradermal and 100% epidermal

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: 22 (2 weeks after epidermal challenge)
- Exposure period: 24 hours
- Test groups: 100 %
- Control group: untreated since no vehicle was used
- Site:shaved area, over the injection sites
- Concentrations: 100%
- Evaluation (hr after challenge): 24 and 48 h after removal of bandages

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no effects

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 100%. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no effects.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100%

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no effects

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: 10.0. Clinical observations: no effects.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Executive summary:

The contact sensitization of ITTFEP (purity 82.3%) to guinea pigs (Ibn: GOHI; SPF-quality guinea pigs (synonym: Himalayan spotted)) was determined in a GLP compliant test according to OECD 406, EU Method B.2 and OPPTS 870.2600. Since the study from Acrelin (2001) was performed under GLP and according the guideline and based on the good documentation the study was awarded with Klimisch 1. 

 

For the contact sensitization test 10 males and 10 females were first intradermally inducted (Day 1), then epidermally inducted (day 8) and epidermally challenged for 24 hours on day 22. Readings were performed 24 and 48 hours after removing the dressings. FCA was used in combination as vehicle. Concentrations were 5% for intradermal and 100% for epidermal applications.

 

There were no clinical findings during the study. In none of the readings any unusual sensitization findings other than in the controls were found.

  

It can be concluded that under the experimental conditions the test substance is not a skin sensitizer for guinea pigs according to the testing scheme from Magnuson and Kligman.

 

According to the classification criteria set out in Directive 67/548/EEC and Regulation (EC) No. 1272/2008 the substance does not fulfil the criteria for classification as skin sensitizer.