Reaction mass of (2R,7aR)-2,4,6,6-Tetramethyl-7,7a-dihydro-1,3-benzodioxol-5(6H)-one and (2S,7aS)-2,4,6,6-Tetramethyl-7,7a-dihydro-1,3-benzodioxol-5(6H)-one

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant guideline study. Available as unpublished report. No restrictions, fully adequate for assessment.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Reference 2

Reference Type:

other: Amendment to the report

Title:

Unnamed

Year:

1994

Report date:

1994

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)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

162691-58-9

EC Number:

605-300-0

Cas Number:

162691-58-9

IUPAC Name:

162691-58-9

Details on test material:

- Name of substance (as cited in study report): Asta-C9-Acetal
- Physical state/ appearance : liquid, yellowish
- Storage conditions: refrigirator, exclusion of light

In vivo test system

Test animals

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River GmbH - Wiga, Sulzfeld, FRG
- Age at study initiation: Young adult animals
- Weight at study initiation: 296 - 380 g
- Housing: 5 animals per Makrolon, type IV cage; Bedding: Granulat Typ 3/4 (staubfrei); SSNIFF
- Diet: Kliba Labordiät 341 (Kaninchen-Meerschweinchen-Haltungsdiät) ad libitum
- Water: tap water (with about 2 g of ascorbic acid per 10 L water) ad libitum.
- Acclimation period: 7 days before study start

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Photoperiod (hrs dark / hrs light): 12 / 12

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

olive oil

Induction 2

Concentration / amount:

- Intradermal induction: test substance 5% in olive oil
- Epicutaneous induction: unchanged test substance
- Challenge; 75% in olive oil

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

olive oil

Challenge 2

Concentration / amount:

- Intradermal induction: test substance 5% in olive oil
- Epicutaneous induction: unchanged test substance
- Challenge; 75% in olive oil

No. of animals per dose:

Test group: 20
Control group 1: 10
Control group 2: 10

Details on study design:

PRETEST:
- For detecting a possible influence on irritating effects of previous intradermal treatment with Freund's adjuvant, animals pretreated with Freund's adjuvant / 0.9% aqueous NaCl-solution (1:1) each, in the same manner as intradermal induction about 3 weeks prior to the application of the test substance were used .
- Amount applied: 2 x 2 cm filter paper strips were applied to the skin of the flanks under an occlusive dressing (the bandage consists of rubberized linenpatches 4 x 4 cm from Russka, test patch 5 x 5 cm of Idealbinde from Pfälzische Verbandstoff-Fabrik, and Fixomull Stretch (adhesive fleece) from Beiersdorf AG). The test filter paper strip was soaked in the test substance or test substance formulation; thus, the animals were exposed to about 0.15 g of the test substance or test substance formulation.
- Exposure period: The test substance was applied 2 times for 24 hours within a period of 96 hours in order to detect nonspecific phenomena that are not caused by a sensitization reaction but could possibly be attributed to a shift in the irritation threshold.
- Site of application: flank, respective on the same area
- Number of test animals: 4 per test concentration
- Readings: about 24 and 48 h after the beginning of application
- Assessment of the skin findings: According to Draize

INDUCTION EXPOSURE: Intradermal induction
- Injections for the test group: 6 intradermal injections in groups of two per animal
A) front row : 2 injections each of 0.1 mL Freund's adjuvant without test substance emulsified with 0.9% aqueous NaCl-solution in a ratio of 1:1
B) middle row: 2 injections each of 0.1 mL of the test substance formulation
C) back row : 2 injections each of 0.1 mL Freund's adjuvant / 0.9% aqueous NaCl-solution (1:1) with test substance
- Injections for control groups 1 and 2: The animals were given the same injections (A, B, C) but without test substance, only with the formulating agent.
- Site of application: shoulder
- Readings: 24 h after the beginning of application
- Assessment of the skin findings: analogous to the pretest

INDUCTION EXPOSURE: Percutaneous induction
- Percutaneous induction was carried out one week after intradermal induction
- Amount applied: 2 x 4 cm filter paper strips were applied to the skin of the shoulder under an occlusive dressing (the bandage consists of rubberized linenpatches 6 x 4 cm from Russka and Fixomulle Stretch (adhesive fleece) from Beiersdorf AG) . The filter paper strip was soaked in the test substance; thus, the animals were exposed to about 0.3 g of the test substance . The control groups were not treated, since the test substance was applied unchanged and thus no solvent was used .
- Duration of exposure : 48 hour
- Site of application: shoulder,
- Readings: 48 h after the beginning of application
- Assessment of the skin findings: analogous to the pretest

CHALLENGE EXPOSURE
- Test concentration : non-irritant concentration
- Challenge: 21 days after intradermal induction
- Amount applied : 2 x 2 cm filter paper strips were applied to the skin of the flank under an occlusive dressing (the bandage consists of rubberized linenpatches 4 x 4 cm from Russka, test patch .5 x 5 cm of Idealbinde from Pfälzische Verbandstoff-Fabrik, and Fixomull(D Stretch (adhesive fleece) from Beiersdorf AG) . The test filter paper strip was soaked in the test substance formulation ; thus the animals were exposed to about 0.15 g of the test substance formulation .
Treatment of the test group and of control group 1 with the test substance formulation. Additionally olive oil DAB 10 was applied as a vehicle . Control group 2 only received olive oil DAB 10
- Duration of exposure: 24 hours
- Site of application: intact flank
- Readings: 24 and 48 h after the removal of the patch
- Assessment of the skin findings: analogous to the pretest

POSITIVE CONTROL:
A positive control (reliability check) with a known sensitizer is not included in this study however a separate study will be performed twice a year in the
laboratory .

Positive control substance(s):

yes

Remarks:

1-chloro-2,4-dinitrobenzene

Results and discussion

Positive control results:

The positive control with 1-chloro-2,4-dinitrobenzene showed that the test system was able to detect sensitizing compounds under the laboratory conditions chosen.

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

75%

No. with + reactions:

2

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 75%. No with. + reactions: 2.0. Total no. in groups: 20.0.

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

0%

No. with + reactions:

0

Total no. in group:

20

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 0%. No with. + reactions: 0.0. Total no. in groups: 20.0.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

75%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 75%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 4

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

0%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 0%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Any other information on results incl. tables

PRETEST

- In the preliminary test after two 24-hour percutaneous occlusive applications within 96 hours the minimum irritant concentration was found to be the unchanged test substance and the maximum non-irritant concentration a 75% test substance preparation in olive oil DAB 10 (48 hours after the beginnning of application).

MAIN TEST

- After the intradermal induction well-defined erythema and slight edema were observed at the injection sites of the control group animals and test group animals at which only Freund's adjuvant / 0.9% aqueous NaCl-solution (1:1) was applied. Injection of the test substance in olive oil DAB 10 or in Freund's adjuvant / 0.9% aqueous NaCl-solution(1:1) caused well-defined erythema and slight edemain the test group animals. The control group animals which were treated with olive oil DAB 10 showed well-defined erythema.

- The percutaneous induction was only carried out in the test group, because the test substance was applied unchanged and thus no solvent was used. Incrustation, partially open (caused by the intradermal induction) in addition to well-defined erythema and slight edema could be observed in the animals of the test group .

- The challenge with the 75% test substance preparation in olive oil DAB 10 caused well-defined erythema and very slight edema in one out of 20 test group animals. Another test group animal exhibited very slight erythema (findings 24 hours after removal of the patch). The animals of control group 1 did not show any skin reactions.

- Olive oil DAB 10, which was applied as a vehicle did not cause any skin reaction in all animals .

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

Based on the results of the study under the test conditions chosen the test substance does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test.

Executive summary:

The test substance was tested for its sensitizing effect on the skin of 20 guinea pigs in the Maximization Test according to OECD guideline 406 and in compliance with GLP. The intradermal induction with the 5% test substance preparations caused slight to well-defined signs of irritation in the test group animals. After the percutaneous induction with the unchanged test substance the animals of the test group exhibited incrustation, partially open (caused by the intradermal induction) in addition to slight to well-defined signs of irritation. The challenge with the 75% test substance preparation in olive oil DAB 10 caused very slight to well-well-defined signs of irritation in two test group animals. Based on the results of the study under the test conditions chosen it was concluded that the test substance does not have a sensitizing effect on the skin of the guinea pig in the Maximization Test .