4-ethylphenol

Endpoint summary

Description of key information

Read-Across: p-Tolyl alcohol was tested in a skin sensitization study according to OECD Technical Guideline. This study was a modified Draize test conducted with guinea pigs. No indication of skin sensitization was observed with the tested material in this study. Since a read across from p-toloyl alcohol to 4-ethylphenol is appropriate due to expected comparable toxicological properties, the absence of skin sensitization potential can also be assumed for 4-ethylphenol.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Justification for type of information:

Justification for read-across: see attachment

Reason / purpose for cross-reference:

read-across source

Remarks:

p-Cresol

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

yes

Remarks:

The equivalent total dose was administered on one occasion as 4 intradermal injections, each 2.5 times the Injection Challenge Concentration (ICC)

Principles of method if other than guideline:

See "Any other information on materials and methods"

GLP compliance:

not specified

Type of study:

Draize test

Justification for non-LLNA method:

Historical data

Specific details on test material used for the study:

The perfume ingredients used in this study were random samples from commercial batches which had passed quality contral checks for odour and, in some cases, gas liquid chromatography to identify major components. These checks were carried out to ensure that the ingredients tested were representative of production batches.

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

ANIMALS

- Weight at study initiation: about 350 g
- Housing: 2/per cage, same sex
- Diet: pelleted guinea pig diet, cabbage, hay
- Water: ad libitum

Route:

intradermal

Vehicle:

not specified

Concentration / amount:

0.1 mL; 2.5 x ICC

Day(s)/duration:

4 injections at one occasion

No.:

#1

Route:

intradermal and epicutaneous

Vehicle:

not specified

Concentration / amount:

0.1 mL; ICC / ACC

Day(s)/duration:

14 d after induction

No.:

#2

Route:

intradermal and epicutaneous

Vehicle:

not specified

Concentration / amount:

0.1 mL; ICC / ACC

Day(s)/duration:

21 d after induction for positive reactions (controls included). In absence of sensitization reactions, the induction and challenge (controls included) procedures were repeated.

No. of animals per dose:

10 (4 males and 6 females or vice versa)

Details on study design:

For each test material preliminary irritation tests were done in guinea pigs to determine concentrations suitable for sensitization testing.
Guinea pigs were then treated by intradermal injection to induce sensitization and challenged 2 weeks later by both intradermal injection and topical application.
When there was no evidence of sensitization the induction and challenge procedures were repeated.

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

Positive control results:

no data

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Total no. in group:

10

Clinical observations:

No data; only classification as sensitizer / non-sensitizer stated in the current publication.

Remarks on result:

no indication of skin sensitisation

Interpretation of results:

GHS criteria not met

Conclusions:

The tested material was not sensitizing in a modified Draize test with guinea pigs.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Justification for classification or non-classification

Based on information available for a read-across chemical, 4-ethylphenol is not to be classified according to Regulation (EC) No 1272/2008 in terms of skin sensitization.