1,2-Ethanediamine, 4-methylbenzenesulfonate (1:1)

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP compliant guideline study, available as unpublished report, no restrictions in design and/or reporting buth otherwise adequate for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

Toluene-4-sulphonic acid

EC Number:

203-180-0

EC Name:

Toluene-4-sulphonic acid

Cas Number:

104-15-4

IUPAC Name:

4-methylbenzenesulfonic acid

Details on test material:

- Name of test material (as cited in study report): p-Toluolsulfonsäure
- Physical state: grayish white crystalline product
- Purity: >98%
- Storage: in the dark at room temperature, with LEV

In vivo test system

Test animals

Species:

guinea pig

Strain:

Pirbright-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: HOECHST AG, Kastengrund, SPF-Zucht
- Weight at study initiation: mean 351 g (310-394 g)
- Housing: 5 animals per cage, in Makrolon Type 4 cages, on softwood granules
- Diet: ad libitum, ERKA-Mischfutter Nr. 8300 for guinea pigs and rabbits
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 50 ± 20
- Air: fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

physiological saline

Remarks:

0.9%

Induction 2

Concentration / amount:

- Intradermal induction: 0.2%
- Epicutaneous induction: 20%
- Challenge: 10%

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

physiological saline

Remarks:

0.9%

Challenge 2

Concentration / amount:

- Intradermal induction: 0.2%
- Epicutaneous induction: 20%
- Challenge: 10%

No. of animals per dose:

- Test material: 10
- Control: 5

Details on study design:

RANGE FINDING TESTS:
A. EPICUTANEOUS EXPOSURE
- Amount applied: 0.5 mL of the test substance formulation was applied to 2 x 2 cm filter paper strips. This was applied to the skin of the flanks under an occlusive dressing and fixated.
- Concentrations tested: 0.01, 0.1, 1, 5, 10 and 20% dissolved in 0.9% physiological saline
- Exposure period: 24 hours
- Site of application: flank
- Number of test animals: 7 (multiple concentrations tested in the same animal)
- Readings: 24 after the beginning of application

B. INTRADERMAL INDUCTION
To determine the intradermal compatibility the test substance the following preparations were injected in three guinea pigs in groups of two, in a 2 x 4 cm area: 1) 0.1 mL of 0.2% test substance in 0.9% physiological saline, 2) 0.1 mL of 0.04% test substance in 0.9% physiological saline, 3) 0.1 mL of 0.008% test substance in 0.9% physiological saline.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 2 (day 1 intradermal injections + day 9 epicutaneous exposure)
- A total of six intradermal injections in groups of two per animal was made, in a 2 x 4 cm area. These injections were: 1) 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, 2) middle row: 2 injections each of 0.1 mL of the test substance formulation, 3) back row: 2 injections each of 0.1 mL Freund's adjuvant/ 0.9% aqueous NaCl-solution (1:1) with test substance.
- Epicutaneous exposure: 0.5 mL of the test substance was applied to a 2 x 4 cm filter paper strip, which applied to the skin of the shoulder under an occlusive dressing (impermeable film and elastic adhesive bandage).
- Exposure period (epicutaneous): 48 hours
- Control group: The animals were given the same injections (1,2,3) but without test substance, only with the formulating agent. For epicutaneous exposure the control groups received the vehicle only.
- Site: shoulder
- Evaluation: from day 1 till day 8, and after removal of the occlusive epicutanous exposure (48 hours after start of this exposure)

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Exposure: 0.5 mL of the test substance was applied to a 2 x 2 cm filter paper strips were applied to the skin of the flank under an occlusive dressing (impermeable film elastic adhesive bandage).
- Day(s) of challenge: at day 22
- Exposure period: 24 h
- Site: intact left flank
- Evaluation (hr after challenge): 24 and 48 after the removal of the patch

Challenge controls:

The control animals received in the induction exposure the same injections (1,2,3) but without test substance, only with the formulating agent. For epicutaneous exposure the control groups received the vehicle only. With the challenge exposure the control animals received the same exposure as animals from the test group (0.5 mL of 10% test substance in 0.9% physiol. saline).

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 5.0.

Results 2

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10%

No. with + reactions:

0

Total no. in group:

5

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 5.0.

Results 3

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10%

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 10%. No with. + reactions: 0.0. Total no. in groups: 10.0.

Any other information on results incl. tables

RANGE FINDING TESTS

- EPICUTANEOUS EXPOSURE: After treatment with the 20% concentration one animal showed erythema, but a barely perceptible edema. In the other animal very slight edema was observed. At the other tested concentrations no signs of irritation were observed.

- INTRADERMAL INDUCTION: The injection of 0.2% of the test substance resulted in edema, but no erythema. No effects were observed with the other tested concentrations.

MAIN TEST

The intradermal injections with Freund’s adjuvant, with and without test substance, resulted in severe redness and swelling which lasted for one day. In some cases formation of crusts were observed. After removal of the occlusive dressing (day 11) necrosis and scars were observed on these parts of the skin.

Applicant's summary and conclusion

Interpretation of results:

not sensitising

Remarks:

Migrated information

Conclusions:

The test item p-Toluolsulfonsäure is not considered to be a skin sensitizer under the test conditions of this study.

Executive summary:

In a GLP complaint sensitivity study using the Maximization-Test, performed according to OECD guideline 406, Pirbright-Hartley guinea pigs were treated with the test substance. Ten animals were treated with the test substance and five with only the vehicle (physiological saline). The concentrations of the test substance used in the main study were determined by the results of the preliminary study. The intradermal induction of sensitization in the test group was performed using 0.2% of the test substance in both the vehicle and the Freund's Complete Adjuvant/vehicle mixture. Eight days later this was boosted by the topical application of the test substance at 20% concentration over the injections sites. Animals of the control group were treated in the same manner but the selected vehicle was used. Two weeks after the second induction all animals were challenged by topical application of the test substance at 10% concentration. The animals in the test groups showed no response (after 24 and 48 hours). Therefore it can be concluded that the test substance shows no skin sensitizing potential in guinea pigs.