3-methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

Data is from a peer-reviewed publication

Data source

Reference

Reference Type:

publication

Title:

Toxicological Tests on Flavouring Matters

Author:

B. L. Oser

Year:

1965

Bibliographic source:

Food and cosmetics toxicology

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: see Principles below

Principles of method if other than guideline:

A repeated dose study investigating the effect of test substance in rats..

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

3-methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one

EC Number:

204-846-3

EC Name:

3-methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-3-buten-2-one

Cas Number:

127-51-5

Molecular formula:

C14H22O

IUPAC Name:

3-methyl-4-(2,6,6-trimethylcyclohex-2-en-1-yl)but-3-en-2-one

Test animals

Species:

rat

Strain:

other: FDRL

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: No data available
- Age at study initiation: No data available
- Weight at study initiation: Males: 59.5 ±1.5 g; Females: 58.0 ± 1.6 g
- Fasting period before study: No data available
- Housing: Animals were housed individually in wire mesh cages.
- Diet (e.g. ad libitum): Purina Laboratory Chow, ad libitum
- Water (e.g. ad libitum): Fresh water, ad libitum
- Acclimatization period: No data available

ENVIRONMENTAL CONDITIONS
- Temperature (°C):No data available
- Humidity (%):No data available
- Air changes (per hr):No data available
- Photoperiod (hrs dark / hrs light):No data available

Administration / exposure

Route of administration:

oral: feed

Vehicle:

cotton seed oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: The test substance was diluted in cotton-seed oil in a concentration sufficient to provide the predetermined dosage in 2% of the diet. The oil solutions were incorporated into a nutritionally adequate basal ration (Purina Laboratory Chow).

DIET PREPARATION
- Rate of preparation of diet (frequency): Biweekly
- Mixing appropriate amounts with (Type of food): Purina Laboratory Chow
- Storage temperature of food: No data available

VEHICLE
- Justification for use and choice of vehicle (if other than water): Cotton-seed oil
- Concentration in vehicle: 2% of the diet.
- Amount of vehicle (if gavage):No data available
- Lot/batch no. (if required):No data available
- Purity:No data available

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

No data available

Duration of treatment / exposure:

90 days

Frequency of treatment:

Daily

Doses / concentrations

Remarks:

Doses / Concentrations: 3.66 mk/kg (measured conc. 3.55 mg/kg (males) and 4.10 mg/kg (females))

No. of animals per sex per dose:

Total: 60 rats
Control: 15 males, 15 females
3.66 mg/kg: 15 males, 15 females

Control animals:

yes

Details on study design:

- Dose selection rationale: Single dosage levels for each substance were derived from the total estimated daily intake, calculated on a mg/kg body weight basis assuming 50 kg as the average body weight, and multiplying by 100.

Positive control:

No data available

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: No data available

DETAILED CLINICAL OBSERVATIONS: No data available

BODY WEIGHT: Yes
- Time schedule for examinations: Not specified

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No data available

FOOD EFFICIENCY: No data available

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No data available

OPHTHALMOSCOPIC EXAMINATION: No data available

HAEMATOLOGY: Yes
- Time schedule for collection of blood: 6 week and 12 week
- Anaesthetic used for blood collection: No data available
- Animals fasted: No data available
- How many animals: 8 rats of each sex at 6 week period and all rats at 12 week period
- Parameters examined: Hematocrit, hemoglobin, red blood cells white blood cells, neutrophils and lymphocytes.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: 6 week and 12 week
- Anaesthetic used for blood collection: No data available
- Animals fasted: No data available
- How many animals: 8 rats of each sex at 6 week period and all rats at 12 week period
- Parameters examined: Blood urea nitrogen

URINALYSIS: No data available

NEUROBEHAVIOURAL EXAMINATION: No data available

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
At autopsy, liver and kidney weights were recorded.

HISTOPATHOLOGY: Yes
The following organs from half the animals in each group were taken for histological examination: liver, kidneys, stomach,small and large intestines, spleen,pancreas, heart, lungs, bone marrow, muscle, brain, spinal cord, bladder, adrenals, thyroid, pituitary, gonads, salivary glands, and lymph nodes.

Other examinations:

No data available

Statistics:

Statistical limits (P=0.05) for the controls.

Results and discussion

Results of examinations

Clinical signs:

not specified

Mortality:

not specified

Body weight and weight changes:

not specified

Food consumption and compound intake (if feeding study):

not specified

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not specified

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

The males showed a slightly reduced haemoglobin level but the haematocrit and erythrocyte counts were within the control ranges.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

The males also had a mean blood urea nitrogen level somewhat below that of the composite controls.. However, the male control rats showed a mean blood urea nitrogen at 12 wk of 9.2 mg/100 ml; the value at 6 wk was 10.8 compared with 9.9 mg/100 ml for the controls.

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Immunological findings:

not specified

Organ weight findings including organ / body weight ratios:

no effects observed

Description (incidence and severity):

Liver and kidney weights were normal throughout the study.

Gross pathological findings:

no effects observed

Description (incidence and severity):

No significant gross pathological change was observed at autopsy in any of the rats in this study.

Neuropathological findings:

not specified

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Other effects:

not specified

Effect levels

1

Key result

Dose descriptor:

NOAEL

Effect level:

3.55 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Basis for effect level:

clinical biochemistry

gross pathology

haematology

Remarks on result:

other: No toxiceffect were observed

2

Key result

Dose descriptor:

NOAEL

Effect level:

4.1 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

female

Basis for effect level:

clinical biochemistry

gross pathology

haematology

Remarks on result:

other: No toxic effect were observed

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

The test substance was considered to have a NOAEL of 3.55 mg/kg/day in male rats and 4.10 mg/kg/day in female rats after 90-Days of feeding.

Executive summary:

The activity of test substance was studied in a 90-day feeding studies in rats. The test material was given orally in diet to male and female FDRL rats at a dose concentration of 3.66 mg/kg (actual dose received: 3.55 mg/Kg bw/day for males and 4.10 mg/Kg bw/day for females). No significant gross pathological change was observed at autopsy in any of the rats, and only mino effects were seen on hemoglobin and blood urea nitrogen in male rats. The 90-day feeding study corresponded to at least 100 times the maximum estimated human dietary levels, and revealed no evidence of adverse toxic effects. Therefore, NOAEL was considered to be 3.55 mg/bg bw/day in male rats and 4.10 mg/kg bw/day in female rats.