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Toxicological information

Skin sensitisation

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Administrative data

Endpoint:
skin sensitisation: in vivo (LLNA)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2004
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2004
Report date:
2004

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 429 (Skin Sensitisation: Local Lymph Node Assay)
Qualifier:
according to guideline
Guideline:
EPA OPPTS 870.2600 (Skin Sensitisation)
GLP compliance:
yes (incl. QA statement)
Type of study:
mouse local lymph node assay (LLNA)

Test material

Constituent 1
Reference substance name:
Phenylethyl alcohol
IUPAC Name:
Phenylethyl alcohol

In vivo test system

Test animals

Species:
mouse
Strain:
CBA
Sex:
female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Interfauna UK Limited, Blackthorne, Bicester, Oxon, UK
- Age at study initiation: Young adults
- Weight at study initiation: 16.4-20.2g
- Sex: Female
- Number used: 4 per group
- Housing:cage suitables for animals of this strain and weight range
- Diet and water (e.g. ad libitum): Diet (RM1) was supplied by Special Diets Service Limited, Witham, Essex, UK, and mains water, supplied by an automatic system, were available ad libitum
- Acclimation period: 5 days prior to the start of dosing.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/-3°C
- Humidity (%): 30-70%
- Air changes (per hr): a minimum of 15 changes per hr
- Photoperiod (hrs dark / hrs light): Artificial, giving 12 hr light, 12 hr dark

Study design: in vivo (LLNA)

Vehicle:
other: 25% ethanol; 75% diethylphthalate
Concentration:
2.5, 5, 10, 25 or 50% w/v
No. of animals per dose:
4
Positive control substance(s):
other: Hexylcinnamaldehyde
Statistics:
The EC3 value was derived by interpolating two points on the Sensitisation Index (SI) axis, one immediately above and the other immediately below the SI value of 3 (vehicle-treated control values [SI=1] not being used for the latter). Where the data point lying immediately above and below the SI value of three have the co-ordinates a ( the concetration giving the SI immediately below 3) and d(the SI of c), the EC3 value was calculated using the following equation:

EC3=[(3-d)/b-d)] x (a-c)+c

Results and discussion

Positive control results:
The positive control Hexylcinnamaldehyde was tested at concentration of 2.5, 5 and 5% w/v. The results showed a test control ratio average of 6.15.

In vivo (LLNA)

Resultsopen allclose all
Key result
Parameter:
SI
Remarks:
Ratio of test to control lymphocyte proliferation
Value:
ca. 1.06
Test group / Remarks:
2.5% tested concetration
Remarks on result:
other: negative result
Key result
Parameter:
SI
Remarks:
Ratio of test to control lymphocyte proliferation
Value:
ca. 1.01
Test group / Remarks:
5% tested concetration
Remarks on result:
other: negative result
Key result
Parameter:
SI
Remarks:
Ratio of test to control lymphocyte proliferation
Value:
ca. 0.87
Test group / Remarks:
10% tested concentration
Remarks on result:
other: negative result
Key result
Parameter:
SI
Remarks:
Ratio of test to control lymphocyte proliferation
Value:
ca. 0.95
Test group / Remarks:
25% tested concentration
Remarks on result:
other: negative result
Key result
Parameter:
SI
Remarks:
Ratio of test to control lymphocyte proliferation
Value:
ca. 0.84
Test group / Remarks:
50% tested concetration
Remarks on result:
other: negative result

Any other information on results incl. tables

Skin sensitisation potential of Phenylethyl Alcohol
Concentration of the test substance No of lymph nodes assayed Disintegration per min. (dpm) dpm per limph node Test control ratio
         
0 8 5432 679 N/A
2.5 8 5776 722 1.06
5 8 5504 688 1.01
10 8 4709 589 0.87
25 8 5167 646 0.95
50 8 4536 567 0.84
50 Greater than 50% w/v (greater than 12500 µg/cm2

Skin sensitisation potential of the positive control substance ( Hexylcinnamaldehyde)

Concentration of the test substance No of lymph nodes assayed Disintegration per min. (dpm) dpm per limph node Test control ratio
         
0 8 2570 321 N/A
2.5 8 16088 2011 6.26
5 8 15659 1957 6.1
10 8 15611 1951 6.08

Applicant's summary and conclusion

Interpretation of results:
not sensitising
Remarks:
Migrated information
Conclusions:
The test material Phenylethyl Alcohol was not a sensitiser under the condition of the test.
Executive summary:

In this study, Phenylethyl alcohol was assessed for its skin sensitisation potential using the mouse Local Lymph Node Assay. Concentration of 2.5, 5, 10, 25 or 50% w/v preparation in 25% ethanol/ 75% diethylphthlate were tested on groups of four female mice. Hexylcinnamaldehyde at concentration of 2.5, 5 and 5% w/v was used as positive control. The test material was applied to the dorsal surface of each ear and the test was repeated for three consecutive days, following the same procedure.

The results showed that the application of the test substance at concentrations of 2.5, 5, 10, 25 or 50% w/v preparation in 25% ethanol/ 75% diethylphthlate resulted in an isotope incorporation which was less than 3 -fold at all concentrations. Consequently, the test substance is unlikely to be a skin sensitizer. The estimated concertation giving rise to a 3 -fold increase in lymphocyte proliferation (EC3) was greater than 50%w/v (greater than 12500 µg/cm2 ), therefore 2 -phenylethyl alcohol is not considered to be a sensitizer under the test conditions.