Pentane-2,4-dione

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1985-01-09 to 1985-04-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Conduction and documentation of study very acceptable. Study report available.

Data source

Reference

Reference 1

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Reference 2

Reference Type:

publication

Title:

The acute toxicity and primary irri-tancy of 2,4-pentanedione

Author:

Ballantyne, B., Dodd, D.E., Myers R.C., Nachreiner, D.J.

Year:

1986

Bibliographic source:

Drug and Chemical Toxicology, 9, 133-146

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: as reported in test report

Deviations:

no

Principles of method if other than guideline:

undiluted TS applied on the shaved dorsal skin (25 cm2) of 3-5  male or female New Zealand White rabbits/group; occlusive contact for 24  h; 14 d post application period; 5 doses tested.

GLP compliance:

not specified

Test type:

fixed dose procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Pentane-2,4-dione

EC Number:

204-634-0

EC Name:

Pentane-2,4-dione

Cas Number:

123-54-6

Molecular formula:

C5H8O2

IUPAC Name:

pentane-2,4-dione

Details on test material:

- Name of test material (as cited in study report): 2,4-Pentanedione
- Substance type: industrial chemical
- Physical state: liquid
- Analytical purity: > 99%
- Impurities (identity and concentrations): not reported
- Lot/batch No.: 496500
- Expiration date of the lot/batch: not given
- Stability under test conditions: stable
- Storage condition of test material: not given

Test animals

Species:

rabbit

Strain:

New Zealand White

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 2.0 to 3.0 kg
- Fasting period before study: no
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: 25 cm2

REMOVAL OF TEST SUBSTANCE
- Washing (if done): removal of excess fluid
- Time after start of exposure: 24 h


TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2, 1 and 0.5 ml/kg bw
- Constant volume or concentration used: yes


VEHICLE not used

Duration of exposure:

24 h

Doses:

2, 1 and 0.5 ml/kg bw

No. of animals per sex per dose:

5 per sex and does

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: one hour, 7 and 14 days after application
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

Moving average method of Thompson

Results and discussion

Preliminary study:

not reported

Effect levels

Effect levels 1

Sex:

female

Dose descriptor:

LD50

Effect level:

790 mg/kg bw

Based on:

test mat.

95% CL:

560 - 980

Effect levels 2

Sex:

male

Dose descriptor:

LD50

Effect level:

1 370 mg/kg bw

Based on:

test mat.

95% CL:

770 - 2 100

Mortality:

death occurred within 1-24 h  after application; 

Clinical signs:

other: signs of toxicity at 970 mg/kg or more: dilated   pupils, salivation and convulsions (high dose); local erythema, edema and  necrosis (persisted for 1-7 d) and scab formation at day 14; 

Gross pathology:

dead animals showed red mottled lungs, patchy congestion of tracheal mucosa, and a few stomachs with superficial black  foci at necropsy.

Other findings:

- Organ weights: not affected by study

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Substance is harmful in contact with skin under the conditions used.

Executive summary:

Acetylacetone (2,4 -Pentanedione) was administered to groups of 5 male and 5 female New Zealand White Rabbits. The rabbits received the test material (1.41 and 0.812 ml/kg bw respectively) by retaining the material under impervious sheeting on the clipped intact skin of the trunk.

The LD50 for male rabbits receiving 2,4 -Pentanedione were 790 mg/kg bw for males and 1370 mg/kg bw for females. Erythema,. edema and a few instances of necrosis and scab formation were observed at the dose sites. Signas of toxicity included dilated pupils, bloody discharge from the mouth, salviation abd in one animal convulsions. Time to death ranged from 45 min to one day. Gross pathologic examination revealed mottled and red lungs, a few tracheas with red patches and a few stomache with black foci on the surface. The test substance is harmful in contact with skin under the conditions used.