Guaiacol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The purity of the test substance was known: 99.4%. The authors argued that the in vivo data were generated in studies carried out since 1981 according to OECD Test Guideline 404 and following the principles of Good Laboratory Practice.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Reference 2

Reference Type:

publication

Title:

Skin irritation: reference chemicals data bank

Author:

Bagley D.M., Gardner J.R., Holland G., Lewis R.W., Regnier J.F., Stringer D.A., Walker A.P.

Year:

1996

Bibliographic source:

Toxicology in Vitro, 10, 1-6.

Reference 3

Reference Type:

publication

Title:

Methods for the study of irritation and toxicity of substances applied topically to the skin and mucous membranes

Author:

Draize J.H., Woodard G., Calvery H.O

Year:

1944

Bibliographic source:

Journal of Pharmacology, 82, 377-390.

Reference 4

Reference Type:

publication

Title:

Skin irritation and corrosion: reference chemicals data bank.

Author:

ECETOC

Year:

1995

Bibliographic source:

Technical Report N°66, 208. European Centre for Ecotoxicology and Toxicology of Chemicals, Brussels.

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

yes

Remarks:

The heating equipment failed during the acclimatisation period, resulting in the low temperatures recorded. Temperature was typically greater than 14°C.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Guaiacol

EC Number:

201-964-7

EC Name:

Guaiacol

Cas Number:

90-05-1

Molecular formula:

C7H8O2

IUPAC Name:

Phenol

Details on test material:

Guaiacol was purchase from Givaudan-Roure and its purity was 99.4%.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS:
- Source: from Gorseside Rabbits, Northchurch, Berkhamsted, Herfordshire, and delivered by road transport
- Age at study initiation: 10-12 weeks
- Weight at study initiation: approximatively 2 kg
- Housing: individually in grid bottomed metal cages
- Diet: ad libitum, a commercially available antibiotic free rabbit diet (SQC standard rabbit pellets produced by special Diets Services, Witham, Essex)
- Water: ad libitum, mains drinking water via automatic nozzles
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS:
- Temperature (°C): 17-23°C
- Humidity (%): 37-68%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 h light/ 12h dark

IN-LIFE DATES: from 8th november to 15th november 1988

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

Amount applied: 0.5 ml, undiluted

Duration of treatment / exposure:

4 hour(s)

Observation period:

7 days

Number of animals:

4

Details on study design:

TEST SITE:
- Area of exposure: over a 2.5 cm square (approximately 6 square cm)
- % coverage: no data
- Type of wrap if used: "Elastoplast" elastic adhesive bandage 10 cm wide.

REMOVAL OF TEST SUBSTANCE:
- Washing: The treated site was cleansed by gentle swabbing with cotton wool soaked in warm water
- Time after start of exposure: 4 hours

SCORING SYSTEM: The treated area was scored for erythema and oedema using a numerical system based on that described by Draize et al. (1944) and the primary dermal irritation index (PDII) was calculated.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

1.8

Max. score:

4

Reversibility:

not fully reversible within: 7 days

Results 2

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 3

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual data

Results 4

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 5

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 6

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0.6

Max. score:

4

Reversibility:

fully reversible

Results 7

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 8

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 9

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 10

Irritation parameter:

edema score

Basis:

animal #4

Time point:

24/48/72 h

Reversibility:

other: No individual data

Remarks on result:

other: No individual score

Results 11

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

24/48/72 h

Score:

2.38

Irritant / corrosive response data:

The publication is old. Therefore individual scores are not available.

Other effects:

none

Any other information on results incl. tables

Remark: 

The primary irritation index (PII = PDII) = ((SUM erythema  24/48/72 hr)+ (SUM oedema 24/48/72 hr)) / (3 x Number of animals). Since no scale was 

identified in the OECD protocol, the AFNOR scale was used to interpret the results as following: PDII below 0.5, non-irritant; 0.5-3,  slightly irritant; 

3-5, moderately irritant; 5.8, severely irritant.
The numerical scores obtained were summed and a mean was calculated. When the mean value obtained for either erythema or oedema equalled 

or exceeded 2, the test substance was considered as irritant.
The scores were determmined from the numerical values given to the irritation observed at the 24, 48 and 72 hour. The corresponding PDII was  

2.38 and guaiacol was determined as "slightly irritant".

Applicant's summary and conclusion

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

Based on CLP criteria the substance is not classified as irritant. Only slight irritation was observed. However, erythema is not fully reversible within 7 days (observation period). Therefore in a conservative approach the substance is classified Skin. Irrit. Cat. 2, H315.

Executive summary:

In a dermal irritation study (Haynes for RIFM, 1988), four New-Zealand White female rabbits were dermally exposed to 0.5 ml of guaiacol for 4 hours to left flank (6 cm square).  Test sites were covered with a semi-occlusive dressing for 4 hours. Animals then were observed for 7 days.  Irritation was scored by the method of Draize.
In this study, guaiacol is slightly irritating to the skin. However, erythema is not fully reversible within 7 days (observation period). Therefore in a conservative approach the substance is classified Skin. Irrit. Cat. 2, H315.

Guaiacol is officialy classified as Skin Irrit. Category 2 (H315: Causes skin irritation) according to the Regulation (EC) n° 1272/2008 annex VI table 3.