1-[4-(1,1-dimethylethyl)phenyl]-3-(4-methoxyphenyl)propane-1,3-dione

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:

comparable to guideline study with acceptable restrictions

Remarks:

Comparable to guideline study with deficiencies in reporting.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

: no grading but only sensitisation-positive animals were reported.

GLP compliance:

no

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

The study was performed in 1982.

Test material

Test material information

Constituent 1

Reference substance name:

1-[4-(1,1-dimethylethyl)phenyl]-3-(4-methoxyphenyl)propane-1,3-dione

EC Number:

274-581-6

EC Name:

1-[4-(1,1-dimethylethyl)phenyl]-3-(4-methoxyphenyl)propane-1,3-dione

Cas Number:

70356-09-1

Molecular formula:

C20H22O3

IUPAC Name:

1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione

Test material form:

solid

Details on test material:

- Name of test material : BMDBM
- Substance type: organic
- Physical state: solid

In vivo test system

Test animals

Species:

guinea pig

Strain:

Himalayan

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Institute of biological research, Fuellingsdorf, Switzerland
- Weight at study initiation: 300 - 450 g
- Housing: Type 3 wire mesh cages
- Water: ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2 °C
- Humidity (%): 45 ± 10 %
- Photoperiod (hrs dark / hrs light): 12/12

Study design: in vivo (non-LLNA)

Induction

Route:

intradermal and epicutaneous

Vehicle:

other: 2-phenylethanol

Concentration / amount:

Induction:
day 0: 5 % in FCA
day 8: 20 % in 2-phenylethanol

Challenge

Route:

epicutaneous, occlusive

Vehicle:

other: 2-phenylethanol

Concentration / amount:

Challenge:
day 21: 20 % and 6 % in 2-phenylethanol

No. of animals per dose:

Experimantal group: 20 animals

Details on study design:

MAIN STUDY
A. INDUCTION EXPOSURE
On day 0, each of the 20 animals received 2 intradermal injections of either the test item, FCA, or FCA + test item. On day 8, occlusive topical application of the test item for 2 days was performed.
- Site: neck

B. CHALLENGE EXPOSURE
On day 21, an occlusive patch with the test item (20 % and 6 %) in 2-phenylethanol was applied for 24 h.
- Site: flank
- Evaluation: 24 and 48 h after removing the patch

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Key result

Reading:

other: mean of two readings after 24 and 48h

Hours after challenge:

48

Group:

test chemical

Dose level:

6 % and 20 %

No. with + reactions:

0

Total no. in group:

20

Results 2

Reading:

1st reading

Group:

positive control

Remarks on result:

not measured/tested

Results 3

Reading:

1st reading

Group:

negative control

Remarks on result:

not measured/tested

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The occlusive challenge with BMDBM, 20 % and 6 % in 2-phenylethanol 3 weeks after the initial injections does not elicit allergic reactions in guinea pigs. As the number of positive results is 0 in a group of 20 treated animals, no classification as skin sensitiser is needed.

Executive summary:

The occlusive challenge with BMDBM, 20 % and 6 % in 2-phenylethanol 3 weeks after the initial injections does not elicit allergic reactions in guinea pigs.

As the the number of positive results is 0 in a group of 20 treated animals, no classification as skin sensitising according to GHS and CLP is needed.