Farnesol

Sensitisation data (human)

Administrative data

Endpoint:

sensitisation data (humans)

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Study not conducted in accordance with a published test guideline, however study is well-designed and is GCP-compliant.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Type of sensitisation studied:

skin

Study type:

study with volunteers

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The test substance was applied as impreganated patches to the same area of skin of volunteers, 3 times per week for 3 weeks (24 hour contact time each application) for a total of 9 applications. Two weeks after the last application, a challenge patch was applied to a virgin test site adjacent to the original induction patch site. The patch was removed and the site scored 24 and 72 hours after application

GLP compliance:

yes

Remarks:

GCP-compliant

Test material

Test material information

Constituent 1

Reference substance name:

Farnesol

EC Number:

225-004-1

EC Name:

Farnesol

Cas Number:

4602-84-0

Molecular formula:

C15H26O

IUPAC Name:

farnesol

Method

Type of population:

general

Ethical approval:

not specified

Subjects:

- Number of subjects exposed: 115 but 107 completed the study
- Sex: male and female
- Age: 17 to 77 years
- Demographic information: Age and sex of each participant provided

Clinical history:

- History of allergy or casuistics for study subject or populations: Participants were absent of any visible skin disease and did not have a history of adverse reactions to cosmectics or other personal care products

Controls:

None

Route of administration:

dermal

Details on study design:

TYPE OF TEST(S) USED: patch test (epicutaneous test)

ADMINISTRATION
- Type of application: occlusive
- Description of patch: 3/4" x 3/4" absorbent pad portion of an adhesive dressing
- Concentrations: 15%
- Volume applied: 0.2 mL
- Testing/scoring schedule: 3 times per week (Monday, Wednesday, Friday) for 3 weeks, total of 9 applications
- Removal of test substance: Patch removed 24 hours after each application

EXAMINATIONS
- Grading/Scoring system: 0 -4 scale for erythema plus additional description of dermal sequelae
- Statistical analysis: None

Results and discussion

Results of examinations:

Observations remained within normal limits throughout the study. One participant exhibited extensive tape reaction by the sixth induction exposure and subsequent applications were discontinued. A second participant exhibited mild erythema and oedema 24 and 72 hours post-challenge application; erythema was barely perceptible 96 hours post-challenge application. A third participant exhibited mild to barely perceptible erythema with transient oedema during the first few induction exposures and at 24 and 72 hours post-challenge application. One participant exhibited barely perceptible erythema in the first few Induction applications and two participants exhibited mild to barely perceptible erythema in the last few induction applications.

NO. OF PERSONS WITH/OUT REACTIONS COMPARED TO STUDY POPULATION
- Number of subjects with positive reactions: 3 (mild reactions or worse) - one due to reaction to tape
- Number of subjects with negative reactions 98
- Number of subjects with equivocal reactions: 3 (barely perceptible)

OTHER RESULTS:
One participant that exhibited a noted post-challenge reaction was retested with a single occlusive patch application at 5 sites which was scored 24 hours and 72 hours post application. Applications of 15%, 5.0% and 2.5% formulation, vehicle (DEP/Ethanol), positive control (2% sodium lauryl sulphate) and negative control (saline) were assessed at 24 and 72 hours post application. Erythema was barely perceptible at 24 hours for all test item concentrations and no response was observed at 72 hours. The results show no evidence of an allergic response and can be considered idiosyncratic in origin. The vehicle treatment, positive control and negative control responses were as expected.

Applicant's summary and conclusion

Conclusions:

From the 107 subjects completing the study, only three subjects exhibited a mild but time limited (transient) response during the induction phase. The results showed no evidence of an allergic reaction. The test item applied at a 15% formulation is not consdiered to be a skin sensitiser.

Executive summary:

The test item was applied as impregnated patches at 15% concentration to the same area of skin in 115 volunteers, 3 times per week for 3 weeks (24 hour contact time for each application). A total of 9 applications were made, each of which were scored approximately 24 hours later. Two weeks after the last application, a challenge patch was applied to a virgin test site. The patch was removed and the site was scored 24 and 72 hours after application. 107 subjects completed the study and reactions were seen in three participants. One response was not treatment-related (reaction to adhesive tape) and the other two responses were mild and transient (three occasions during induction). A participant with a mild response to the challenge did not react similarly on retesting in a further challenge application. The results show no evidence of an allergic response and can be considered idiosyncratic in origin. This study is reliable with restrictions (Klimisch 2) as it was well-designed and GCP-compliant, however no standard guideline was followed.

The test item applied at a 15% formulation is not considered to be a skin sensitiser.