2,6,6-trimethoxy-2-vinyltetrahydropyran

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

The study was conducted in 1979.

Reliability:

2 (reliable with restrictions)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Induction: Days 0 – 20.
On Day 0, 0.1 mL of the test material undiluted and at progressively diluted solutions were applied to an area measuring 8 cm2 on the clipped flank skin of six guinea pigs per concentration groups.
The applications were repeated daily for three weeks, or done 5 times weekly during four weeks, always using the same skin site. Te application site was left uncovered. If very strong skin reactions were provoked then the application site was changed.

Challenge: Days 21 to 35.
To determine whether or not contact sensitisation was induced, all groups of guinea pigs previously treated for 21 days, as well as 6 to 8 untreated or only with the vehicle pre-treated controls are tested on Days 21 and 35 on the contralateral flank with the test material at the minimal irritating and some lower concentrations. The minimal irritating concentration of each material is used in order to confirm the biological activity determined before starting the induction (Day -1) and to exclude false results based on instability of the test materials. These tests are performed by applying with a pipette 0.025 mL of each concentration to skin areas measuring 2 cm2, the reactions being read after 24, 48 and / or 72 hours. This procedure enables to determine the minimal sensitising concentration necessary for inducing allergic contact hyper-sensitivity and the minimal eliciting concentration necessary to cause a positive reaction.
The test material is considered allergenic at a concentration when at least one out of the eight animals of this concentration group shows positive reactions with non-irritant concentrations used for challenge, i.d. its threshold concentration causing skin-reactions is shifted to the lower part of the concentration range used for challenge.

GLP compliance:

no

Remarks:

Study pre-dates GLP.

Type of study:

open epicutaneous test

Test material

Test material information

Constituent 1

Reference substance name:

2,6,6-trimethoxy-2-vinyltetrahydropyran

EC Number:

230-983-3

EC Name:

2,6,6-trimethoxy-2-vinyltetrahydropyran

Cas Number:

7392-19-0

Molecular formula:

C10H18O

IUPAC Name:

2,2,6-trimethyl-6-vinyltetrahydro-2H-pyran

Test material form:

not specified

Details on test material:

- Name of test material: Limetol

In vivo test system

Test animals

Species:

guinea pig

Strain:

not specified

Sex:

not specified

Details on test animals and environmental conditions:

No data

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

epicutaneous, open

Vehicle:

other: Ethanol

Induction 2

Concentration / amount:

3, 10, 30 and 100 %

Challenge

Challenge 1

Route:

epicutaneous, open

Vehicle:

other: Ethanol

Challenge 2

Concentration / amount:

3, 10, 30 and 100 %

No. of animals per dose:

6 animals / dose

Details on study design:

Induction: Days 0 – 20.
On Day 0, 0.1 mL of the test material undiluted and at progressively diluted solutions were applied to an area measuring 8 cm2 on the clipped flank skin of six guinea pigs per concentration groups.
The applications were repeated daily for three weeks, or done 5 times weekly during four weeks, always using the same skin site. Te application site was left uncovered. If very strong skin reactions were provoked then the application site was changed.

Challenge: Days 21 to 35.
To determine whether or not contact sensitisation was induced, all groups of guinea pigs previously treated for 21 days, as well as 6 to 8 untreated or only with the vehicle pre-treated controls are tested on Days 21 and 35 on the contralateral flank with the test material at the minimal irritating and some lower concentrations. The minimal irritating concentration of each material is used in order to confirm the biological activity determined before starting the induction (Day -1) and to exclude false results based on instability of the test materials. These tests are performed by applying with a pipette 0.025 mL of each concentration to skin areas measuring 2 cm2, the reactions being read after 24, 48 and / or 72 hours. This procedure enables to determine the minimal sensitising concentration necessary for inducing allergic contact hyper-sensitivity and the minimal eliciting concentration necessary to cause a positive reaction.
The test material is considered allergenic at a concentration when at least one out of the eight animals of this concentration group shows positive reactions with non-irritant concentrations used for challenge, i.d. its threshold concentration causing skin-reactions is shifted to the lower part of the concentration range used for challenge.

Results and discussion

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

504

Group:

test chemical

Dose level:

100 %

No. with + reactions:

0

Total no. in group:

6

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 504.0. Group: test group. Dose level: 100 %. No with. + reactions: 0.0. Total no. in groups: 6.0.

Any other information on results incl. tables

Capacity to cause allergic sensitisation

After daily applications over 3 weeks Concentration %	Sensitisation rate number of animals Positive / total
	Day 21	Day 35
100	0 / 6	0 / 6
30	0 / 6	0 / 6
10	0 / 6	0 / 6
3	0 / 6	0 / 6

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test substance does not sensitise the guinea pig.

Executive summary:

The test substance was assessed for skin sensitisation potential using an open epicutaneous test on guinea pigs. The test substance was not sensitising under the conditions of the test.