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Diss Factsheets

Toxicological information

Skin sensitisation

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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:
data from handbook or collection of data
Justification for type of information:
data is from publication.

Data source

Reference
Reference Type:
publication
Title:
Skin sensitzation study of the test chemical
Author:
Sharp
Year:
1978
Bibliographic source:
Toxicology

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: Modified Draize Technique
Principles of method if other than guideline:
Modified Draize Technique was employed to determine the concentrations suitable for sensitization testing [injection challenge concentration(ICC) and application challenge concentration ( ACC) ] of the test chemical
GLP compliance:
not specified
Type of study:
other: Modified Draize Technique
Justification for non-LLNA method:
Currently no LLNA Study is available for assessment.

Test material

Constituent 1
Chemical structure
Reference substance name:
4-(2,6,6-trimethylcyclohex-2-ene-1-yl)-but-3-ene-2-one
EC Number:
204-841-6
EC Name:
4-(2,6,6-trimethylcyclohex-2-ene-1-yl)-but-3-ene-2-one
Cas Number:
127-41-3
Molecular formula:
C13H20O
IUPAC Name:
4-(2,6,6-trimethylcyclohex-2-ene-1-yl)-but-3-ene-2-one
Details on test material:
- Name of test material: alpha -Ionone
- Molecular formula: C13H20O
- Molecular weight: 192.3 g/mol
- Substance type:organic
- Physical state:liquid

In vivo test system

Test animals

Species:
guinea pig
Strain:
Hartley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS

- Weight at study initiation: 350 g
- Housing: Housed in wire mesh cages in pairs of the same sex
- Diet (e.g. ad libitum): Pelleted guinea pig diet, cabbage and hay ad libitum
- Water (e.g. ad libitum): water ad libitum

Study design: in vivo (non-LLNA)

Induction
Route:
intradermal
Vehicle:
other: Yes suitable vehicle was used. (No detailed information )
Concentration / amount:
Induction concentration: 0.1 mL at 2.5 X 0.1(ICC) : 10 guinea pigs
Day(s)/duration:
24 hours
Adequacy of induction:
other: The concentration giving slight but perceptible irritation with no oedema was selected as the injection challenge concentration (ICC).
Challengeopen allclose all
No.:
#1
Route:
intradermal
Vehicle:
other: Yes suitable vehicle was used. (No detailed information )
Concentration / amount:
Challenge concentration: 0.1 mL at 0.1 (ICC) and 30 (ACC): 10 guinea pigs

Day(s)/duration:
24 hours
Adequacy of challenge:
other: The concentration giving slight but perceptible irritation with no oedema was selected as the injection challenge concentration (ICC). The highest concentration which caused no irritation was selected as the application challenge concentration (ACC).
No.:
#2
Route:
epicutaneous, open
Vehicle:
other: Yes suitable vehicle was used. (No detailed information )
Concentration / amount:
Rechallenge concentration: 0.1 mL at 0.1(ICC) and 30 (ACC): 10 guinea pigs

Day(s)/duration:
24 hours
Adequacy of challenge:
other: The concentration giving slight but perceptible irritation with no oedema was selected as the injection challenge concentration (ICC). The highest concentration which caused no irritation was selected as the application challenge concentration (ACC).
No. of animals per dose:
10 guinea pigs (6 male, 4 females or vice versa)
Details on study design:
MAIN STUDY
A. INDUCTION EXPOSURE: Intradermal
- No. of exposures:4
- Exposure period: No Data Available
- Test groups:10 guinea pigs
- Control group: No Data Available
- Site: 4 sites, 2 auxillary and 2 inguinal lymph nodes
- Frequency of applications:1
- Duration: No Data Available
- Concentrations: 0.1 mL at 2.5 X 0.1 (ICC)

B. CHALLENGE EXPOSURE: Intradermal and Epicutaneous
- No. of exposures:1
- Day(s) of challenge: Fourteen days later, challenge test was performed
- Exposure period:24 hours
- Test groups:10guinea pigs
- Control group: No Data Available
- Site: onto the shaved flank in a small circular area
- Concentrations: 0.1 mL at 0.1 (ICC) and 30 (ACC).
- Evaluation (hr after challenge):24 hours

C. RECHALLENGE EXPOSURE
- No. of exposures:1
- Day(s) of challenge:7 Days Later , rechalleange test was performed.
- Exposure period: No Data Available
- Test groups:10 animal
- Control group: 4 animal (same sex)
- Site: Intradermally and topically on opposite flanks
- Concentrations: 0.1 mL at 0.1 (ICC) and 30 (ACC).
- Evaluation (hr after challenge): No Data Available
-Other:

Observations and scoring –
Each injection reaction was given a total score based on size (2 largest diameters), erythema and oedema. Individual reactions were considered positive when their total score was significantly greater than the average total score for control reactions. Application reactions were scored on a 0 to +++ scale. Reactions were examined under a Philips colour-matching unit with 3 Philips 40 W Actinic Blue 05 fluorescent tubes and 3 Philips 40 W White 35 fluorescent tubes.

Challenge controls:
At each challenge with controls, 4 previously untreated animals of the same sex and similar weight to the test animals were treated intradermally and topically on opposite flanks with 0.1 ml aliquots of test substance at the ICC and ACC respectively
Positive control substance(s):
not specified

Results and discussion

Positive control results:
No data

In vivo (non-LLNA)

Resultsopen allclose all
Reading:
1st reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.1 mL at 0.1 (ICC) and 30 (ACC).
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
No skin sensitization was observed.
Remarks on result:
no indication of skin sensitisation
Reading:
2nd reading
Hours after challenge:
24
Group:
test chemical
Dose level:
0.1 mL at 0.1 (ICC) and 30 (ACC).
No. with + reactions:
0
Total no. in group:
10
Clinical observations:
No skin sensitization was observed.
Remarks on result:
no indication of skin sensitisation

Applicant's summary and conclusion

Interpretation of results:
other: not sensitising
Conclusions:
No signs of contact sensitization were observed at 0. 1% ICC and 30% ACC concentrations. Hence,the test chemical was considered to be non-sensitizing to the skin of albino Hartley guinea pigs.
Executive summary:

Modified Draize Technique was employed to determine the concentrations suitable for sensitization testing [injection challenge concentration(ICC) and application challenge concentration ( ACC) ] of the test chemical.

Hartley strain albino guinea pigs bred were used for the study. Four guinea pigs of same sex were used for the preliminary irritation study and 10 guinea pigs were used for the main sensitization study and 4 previously untreated animals of the same sexwere used as challenge controls.

The preliminary irritation tests were done in guinea pigs to determine concentrations suitable for sensitization testing [injection challenge concentration(ICC) and application challenge concentration(ACC) ]

The ICC and ACC for the test chemical was determined to be 0.1% and 30% respectively

In the induction phase, 0.1 ml aliquots of test substance at 2.5 times the ICC were injected intradermally at 4 sites which overlie the 2 auxillary and 2 inguinal lymph nodes. After a rest period of 14 days, each animal was challenged intradermally in one flank and topically in the other with 0.1 ml aliquots of test substance at the respective ICC and ACC: the topical application was made by spreading 0.1 ml of the test substance onto the shaved flank in a small circular area which was not covered. Twenty-four hours later the reactions were scored and apparent sensitization reactions confirmed 7 days later by a second challenge with controls included. At each challenge with controls, 4 previously untreated animals of the same sex were treated intradermally and topically on opposite flanks with 0.1 ml aliquots of test substance at the ICC and ACC respectively.

 

Individual reactions were considered positive when their total score was significantly greater than the average total score for control reactions. Application reactions were scored on a 0 to +++ scale and individual reactions were considered positive if (a) they were + or greater and (b) there were no erythema reactions in controls.

 

No signs of contact sensitization were observed at 0. 1% ICC and 30% ACC concentrations. Hence, the test chemical was considered to be non-sensitizing to the skin of albino Hartley guinea pigs.