2,6,6-trimethylcyclohex-2-ene-1,4-dione

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1997

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Equivalent to OECD 423; GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method B.1 (Acute Toxicity (Oral))

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: ACUTE TOXIC CLASS METHOD (ATC METHOD) BY E. SCHLEDE, U. MISCHKE, R. ROLL, D. KAYSER: A NATIONAL VALIDATION STUDY OF THE ACUTE-TOXIC-CLASS METHOD AN ALTERNATIVE TO THE LD50 TEST. ARCH. TOXICOL. 66: 455-470 (1992).

GLP compliance:

yes

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

EC Number:

214-406-2

EC Name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

Cas Number:

1125-21-9

Molecular formula:

C9H12O2

IUPAC Name:

2,6,6-trimethylcyclohex-2-ene-1,4-dione

Constituent 2

Reference substance name:

2,6,6-Trimethyl-2-cyclohexen-1,4-dion

IUPAC Name:

2,6,6-Trimethyl-2-cyclohexen-1,4-dion

Constituent 3

Reference substance name:

Oxoisophoron

IUPAC Name:

Oxoisophoron

Details on test material:

- NAME OF TEST SUBSTANCE: OXOISOPHORON
- CHEMICAL NAME: 2,6,6-TRIMETHYL-2-CYCLOHEXEN-1,4-DION
- SUBSTANCE NUMBER: 96/87
- BATCH NUMBER: NOT KNOWN
- CAS NUMBER: 1125-21-9
- DEGREE OF PURITY/CONTENT: 98.87 A%
- DATE OF MANUFACTURING: 18-MAY-1995
- PHYSICAL STATE/APPEARANCE: LIQUID, YELLOW
- STORAGE CONDITIONS: ROOM TEMPERATURE

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, Biberach, FRG
- Age at study initiation: young adult animals
- Weight at study initiation: 150-300 g
- Fasting period before study: 16 h
- Housing: single
- Diet (e.g. ad libitum): Kliba-Labordiaet 343, Klingenthalmühle AG, Kaiseraugst, Switzerland, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: at least 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12 h/12 h

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 40 g/100 mL
- Amount of vehicle (if gavage): 5 mL/kg bw
- Justification for choice of vehicle: The test substance could not be homogenized in water.

MAXIMUM DOSE VOLUME APPLIED: 5 mL/kg bw

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: Based on the physical characteristics of the test substance and the composition no pronounced acute oral toxicity was expected.

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Weighing was performed shortly before administration, weekly thereafter and at the end of the study (before fasting period). Recording of signs and symptoms several times on the day of administration, at least once each workday for th individual animals.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, pathology

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Mortality:

No mortality observed.

Clinical signs:

Males

Signs observed in all males were impaired general state, poor general state, dyspnoea, apathy, staggering and piloerection. These signs had disappeared within few hours or the first two days.

Additional signs observed in 2 of 3 male animals were reported as abdominal position, lateral position, ataxia, atonia and paresis. These signs had disappeared within few hours or the first two days.

Females

Signs observed in all female animals were poor general state, dyspnoea, apathy, ataxia, atonia, paresis and exsiccosis. These signs had disappeared within few hours or the first two days.

Additional signs observed in 2 of 3 females were impaired general state, abdominal position and staggering. These signs had disappeared within few hours or the first two days.

Signs of lateral position and twitching had only been observed in 1 female rat at the very beginning of the observation period.

Body weight:

Mean body weight of male rats [g]:
before application/day 6/ day 13: 189/248/283

Mean body weight of male rats [g]:
before application/day 6/ day 13: 176/200/214

Gross pathology:

no pathologic findings noted.

Applicant's summary and conclusion

Conclusions:

Based on the results of this study, the test substance 2,6,6-trimethylcyclohex-2-ene-1,4-dione does not need to be classified according to EU Directive 67/548 and Regulation (EU) No. 1272/2008.