2,4-dimethylpentan-3-one

Endpoint summary

Description of key information

The test substance caused slight erythema in 5/5 animals when applied to the depilated abdomens of the Guinea pigs at a dose of 0.5 mL for 24 hours under occlusive conditions. All treated animals appeared normal by 24 hours after the end of the exposure to the test material.

The test substance mostly caused slight erythema and moderate edema of the adnexa in unwashed eyes one hour after administration. By 24 hours, 2/3 unwashed eyes appeared clinically normal, and signs of irritation were restricted to slight erythema in the third eye which appeared normal within 48 hours.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

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:

test procedure in accordance with national standard methods with acceptable restrictions

Principles of method if other than guideline:

In a dermal irritation test in Guinea Pigs the test substance was applied, undiluted, at a dose level of 0.5 mL to the depilated abdomens under occlusive conditions for 24 hours.

GLP compliance:

no

Specific details on test material used for the study:

- Name of test substance (as cited in report): 2,4-Dimethyl-3-pentanone

Species:

guinea pig

Strain:

Hartley

Remarks:

Crl:(HA)BP

Details on test animals or test system and environmental conditions:

- Weight at study initiation: 347- 396 g

Type of coverage:

occlusive

Preparation of test site:

other: depilated

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5 mL

Duration of treatment / exposure:

24 hours

Observation period:

14 days

Number of animals:

5

Details on study design:

TEST SITE
- Area of exposure: abdomens
- Type of wrap if used: occlusive wrap

OBSERVATION TIME POINTS
- 24 hours, 48 hours, 14 days

SCORING SYSTEM:
- Method of calculation: Slight, Moderate, Strong, Severe

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 hours after the end of the exposure to the test material

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48 h

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

The test substance caused slight erythema in 5/5 animals when applied to the depilated abdomens of the Guinea pigs at a dose of 0.5 mL for 24 hours under occlusive conditions. All treated animals appeared normal by 24 hours after the end of the exposure to the test material.

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Principles of method if other than guideline:

In rabbit eye irritation test 0.1 mL of the undiluted test substance was applied to the eye of 6 rabbits followed by a 14 day observation period. In three eyes a washing was performed one hour after dosing. The other three eyes remained unwashed. Effects were scored as slight, moderate, strong and severe. In addition fluorescein staining was performed. The test was performed according to internal method TA 150.

GLP compliance:

no

Specific details on test material used for the study:

- Name of test substance( as cited in report): 2,4-Dimethyl-3-pentanone

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

- Weight at study initiation: not determined

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

Three out of six dosed eyes were washed after 1 hour.

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

6

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): In 3/6 eyes with distilled water
- Time after start of exposure: 1 hour

SCORING SYSTEM:
Eyes were scored for Initial, Conjunctiva, Lids, Nictating membrane, Cornea opacity, Iris score, Adnexal stain, Corneal stain and discharge.
Effects were rated Slight, Moderate or Strong.

Irritation parameter:

other:

Remarks:

Overall result

Remarks on result:

other: See irritant/corrosive response data

Irritant / corrosive response data:

The test article mostly caused slight erythema and moderate edema of the adnexa in unwashed eyes one hour after administration. By 24 hours, two of three unwashed eyes appeared clinically normal, and signs of irritation were restricted to slight erythema in the third eye. Immediate washing was palliative. Signs of irritation in washed eyes one hour after dosing were restricted to slight edema and slight erythema of the adnexa, with the exception of moderate erythema of the conjunctiva in a single eye. All washed and unwashed eyes appeared normal by 48 hours after dosing.

Overview of results as reported in study report:

Results	3 unwashed eyes
	IMMED	1 HR	24 HR	48 HR	72 HR	DAY 7	DAY 14
Initial	Slt.
Conjuctiva		Mod.	Slt.
Lids
Nict. Membrane		Mod.	Slt.
Corneal Opacity
Iris
Adnexal Stain			0/3
Corneal Stain			0/3
Discharche		Slt.
Number Normal	0	0	2	3	3

Results	3 washed eyes
	IMMED	1 HR	24 HR	48 HR	72 HR	DAY 7	DAY 14
Initial	Slt.
Conjuctiva		Slt.	Slt.
Lids
Nict. Membrane		Slt.	Slt.
Corneal Opacity
Iris
Adnexal Stain			0/3
Corneal Stain			0/3
Discharche
Number Normal	0	0	2	3	3

Key: Slt. = Slight, Mod. = Moderate, Str. =Strong

No. Responding	Slight	Moderate	Strong	Severe	Fluorescein Stain
					Adnexa	Cornea
Unwashed eyes	3/3				0/3	0/3
Washed eyes	3/3				0/3	0/3

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation:

In a dermal irritation test (Eastman Kodak 1988) in Guinea Pigs the test substance was applied, undiluted, at a dose level of 0.5 mL to the depilated abdomens under occlusive conditions for 24 hours (EPA 1988). The test substance caused slight erythema in 5/5 animals, which was completely reversible within 14 days. All treated animals appeared normal by 24 hours after the end of the exposure to the test material.

 

In addition, in another skin irritation test (BASF 1973) 2 animals were treated for 1, 5, 15 min and 20 hours under occlusive conditions. An application site of 2.5 x 2.5 cm was covered with the liquid test substance. After the application time (1, 5, 15 min and 20 h) the skin was washed with Lutrol (50%). The animals were observed for 8 days and skin changes were recorded daily. After 1 to 15 minute exposure questionable to slight erythema was observed. These effects were fully reversible within 72 hours at most. After 20 hours exposure both animals showed questionable erythema (speckled) which had disappeared within 48 or 72 hours.The mean scores for erythema at 24/48/72 h (20hr exposure) were < 1.

 

The OECD guideline 404 ( Acute Dermal Irritation/Corrosion) states a typical exposure duration of 4 hour under open or semi-occlusive conditions. Therefore the current test (20 or 24 hrs, occlusive) is considered a worst case situation. In addition, it is likely that the depilation process also contributed to the observed redness of the skin. Based on the results obtained under the test conditions chosen, the test material is considered to be not irritating to the skin.

 

Eye irritation:

In rabbit eye irritation test (Eastman Kodak 1988) 0.1 mL of the undiluted test substance was applied to the eye of 6 rabbits followed by a 14 day observation period. In 3 eyes a washing was performed one hour after dosing. The other 3 eyes remained unwashed. Effects were scored as slight, moderate, strong and severe. In addition fluorescein staining was performed. The test article mostly caused slight erythema and moderate edema of the adnexa in unwashed eyes one hour after administration. By 24 hours, two of three unwashed eyes appeared clinically normal, and signs of irritation were restricted to slight erythema in the third eye. Immediate washing was palliative. Signs of irritation in washed eyes one hour after dosing were restricted to slight edema and slight erythema of the adnexa, with the exception of moderate erythema of the conjunctiva in a single eye. All washed and unwashed eyes appeared normal by 48 hours after dosing.  

 

In addition, in another eye irritation test (BASF 1973) 50 µl of the test substance were applied to the conjunctival sac of one eye in 2 animals. The animals were observed after 1 and 24 h on the day of treatment and up to 8 days afterwards. The eyes were not washed out after 24 hours as specified in OECD Guideline 405. One hour after dosing both animals showed slight redness. In one animal this redness had disappeared within 24 hours. In the other animal the redness was fully reversible within 3 days. The eye of this animals also showed some desquamation and tearing. Edema was only observed 1 hour after exposure in one animal. No other effects were reported. The mean score for conjunctiva for 24/48/72 hours (based on available raw data) was ca. 1.0. Mean scores for chemosis and corneal opactity were 0.

 

Based on the results obtained under the test conditions chosen, the test material is considered to be not irritating to the eye.

Justification for classification or non-classification

Based on the available information, classification for skin and eye irritation is not warranted in accordance with EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.