p-isopropylphenyl isocyanate

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: cited in BG 249 (Hoechst study)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

GLP compliance:

not specified

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

1988 OECD 406 was the standard test for skin sensitisation, LLNA test guidance OECD 429 was not available at that time.

Test material

Test material information

Constituent 1

Reference substance name:

p-isopropylphenyl isocyanate

EC Number:

250-439-9

EC Name:

p-isopropylphenyl isocyanate

Cas Number:

31027-31-3

Molecular formula:

C10H11NO

IUPAC Name:

1-isocyanato-4-(propan-2-yl)benzene

Details on test material:

no data

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

paraffin oil

Induction 2

Concentration / amount:

1st: induction: 0.1 ml of a 0.5% p-isopropylphenyl isocyanate solution + freund complete adjuvans
2nd: induction: 0.5 ml of a 10% sodiumlaurylsulfat solution (day 8)
3rd induction: 0.5 ml of a 10% p-isopropylphenyl isocyanate solution (day 9)
challenge: 0.5 ml of 10% p-isopropylphenyl isocyanate solution (day 15)

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

paraffin oil

Challenge 2

Concentration / amount:

1st: induction: 0.1 ml of a 0.5% p-isopropylphenyl isocyanate solution + freund complete adjuvans
2nd: induction: 0.5 ml of a 10% sodiumlaurylsulfat solution (day 8)
3rd induction: 0.5 ml of a 10% p-isopropylphenyl isocyanate solution (day 9)
challenge: 0.5 ml of 10% p-isopropylphenyl isocyanate solution (day 15)

No. of animals per dose:

10 males and 10 females

Results and discussion

In vivo (non-LLNA)

Results

Reading:

1st reading

Hours after challenge:

48

Group:

test chemical

Dose level:

0.5 ml of 10% p-isopropylphenyl isocyanate solution

No. with + reactions:

20

Total no. in group:

20

Clinical observations:

pronounced erythema and oedema

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 48.0. Group: test group. Dose level: 0.5 ml of 10% p-isopropylphenyl isocyanate solution. No with. + reactions: 20.0. Total no. in groups: 20.0. Clinical observations: pronounced erythema and oedema.

Any other information on results incl. tables

Within 48 hours after the challenge all treated animals (20 guinea pigs) revealed a pronounced erythema and oedema. The control animals (5 male and 5 female guinea pigs) had no skin reactions.

Applicant's summary and conclusion

Interpretation of results:

sensitising

Remarks:

Migrated information

Executive summary:

10 males and 10 females received a single intradermal induction with 0.1 ml of a 0.5 % solution of substance in paraffin simultaneous with Freunds complete adjuvans. On day 8 the animals were treated with a 10% solution of sodium laurylsulfate. On day 9 the animals received another dermal induction with 0.5 ml of a 10 % solution of test substance (occlusive application). Challenge was done 15 days after the dermal induction with 0.5 ml of a 10% solution (24 h occlusive). As a result p-isopropylphenyl isocyanate was classified as highly sensitizing.