2-methylpentane-2,4-diol

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-methylpentane-2,4-diol

EC Number:

203-489-0

EC Name:

2-methylpentane-2,4-diol

Cas Number:

107-41-5

Molecular formula:

C6H14O2

IUPAC Name:

2-methylpentane-2,4-diol

Details on test material:

- Name of test material (as cited in study report): HEXYLENE GLYCOL
- Physical state: liquid
- Analytical purity: 99.66%
- Lot/batch No.: G 09770
- Expiration date of the lot/batch: June 1995
- Storage condition of test material: Room temperature

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Interfauna U.K. Ltd., Huntingdon, Cambridgeshire, England.
- Age at study initiation: approximately 11 to 12 weeks of age
- Weight at study initiation: range of 2.6 to 2.9 kg
- Housing: Individually housed in plastic cages with perforated floors
- Diet (e.g. ad libitum): standard laboratory diet SDS Stanrab (P) Rabbit diet ad libitum
- Water (e.g. ad libitum): drinking water ad libitum
- Acclimation period: Rabbits were reported to be acclimated, but number of days not reported

ENVIRONMENTAL CONDITIONS
- Temperature (°C): approximately 19°C
- Humidity (%): 30 - 70%
- Air changes (per hr): approximately 19 air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12

Test system

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL

Duration of treatment / exposure:

4 hours

Observation period:

1 hour after removal of test substance and thereafter 24, 48, and 72 hours after exposure. Additional observations were made on Day 5 for one animal.

Number of animals:

3

Details on study design:

TEST SITE
- Area of exposure: dorso-lumbar region
- % coverage: not reported
- Type of wrap if used: Each treatment site was covered with "Elastoplast" elastic adhesive dressing.


REMOVAL OF TEST SUBSTANCE
- Washing (if done): the treatment site was washed with warm water (30° to 40°C) to remove any residual test substance .
- Time after start of exposure: 4 hours


SCORING SYSTEM: Local dermal irritation was assessed using the prescribed numerical system

Erythema and eschar formation:

No erythema 0
Very slight erythema (barely perceptible) ' 1
Well-defined erythema 2
Moderate to severe erythema 3
Severe erythema (beet redness) to slight eschar formation
(injuries in depth) preventing erythema reading 4



Oedema formation:

No oedema 0
Very slight oedema (barely perceptible) 1
Slight oedema (edges of area well-defined by definite raising) 2
Moderate oedema (raised approximately 1 millimetre) 3
Severe oedema (raised more than 1 millimetre and extending
beyond the area of exposure) 4

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Remarks:

mean

Time point:

24/48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 4 days

Results 2

Irritation parameter:

edema score

Basis:

animal #1

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 3

Irritation parameter:

erythema score

Basis:

animal #2

Remarks:

mean

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 2 days

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 5

Irritation parameter:

erythema score

Basis:

animal #3

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Results 6

Irritation parameter:

edema score

Basis:

animal #3

Remarks:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: not applicable

Irritant / corrosive response data:

DERMAL RESPONSES
Very slight transient erythema was seen in two animals. The skin was normal in one of these animals on Day 3 and in the other on Day 5. The third rabbit showed no dermal response to treatment with HEXYLENE GLYCOL PURE.

Other effects:

CLINICAL SIGNS
There were no signs of toxicity or ill health in any rabbit during the observation period.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Remarks:

slightly irritation

Conclusions:

A single semi-occlusive application of HEXYLENE GLYCOL PURE to intact rabbit skin for four hours elicited very slight transient dermal irritation.

Executive summary:

A skin irritation study on hexylene glycol has been performed in accordance with OECD Guidelines for the Testing of Chemicals No. 404 and in compliance with GLP. In this study, 3 New Zealand White rabbits were exposed to 0.5 mL of undiluted hexylene on the clipped dorsal lumbar region under semi-occlusive conditions. Animals were exposed to the test compound for 4 hours and observations were recorded at 1, 24, 48, and 72 hours after removal of the patch and residual test substance. Additional observations were made on Day 5 for one animal. Skin reactions were scored according to a prescribed numerical system. Very slight transient erythema was observed in 2 animals, and was fully reversible by Day 3 in one animal and by Day 5 in the other. The third rabbit did not display any dermal reactions. In addition, no signs of toxicity or ill health were observed in any rabbit during the observational period. Individual mean scores over 24, 48 and 72h were 1, 0.7 and 0.7 for erythema and 0, 0 and 0 for oedema. Based on the results of this study, hexylene glycol elicited very slight transient dermal irritation to intact rabbit skin.