(R)-p-mentha-1,8-diene

Toxicity to reproduction

Administrative data

Endpoint:

reproductive toxicity, other

Remarks:

data from a 90-day repeated dose toxicity study

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

From January 28 to April 30, 1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

GLP study performed similarly to OECD Guideline 408 but with deviations: dosing 5 days/week instead of 7 days/week; food consumption, haematological and clinical biochemical test not followed

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity in Rodents)

Deviations:

yes

Remarks:

dosing 5 days/week instead of 7 days/week; food consumption, haematological and clinical biochemical test not followed

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

(R)-p-mentha-1,8-diene

EC Number:

227-813-5

EC Name:

(R)-p-mentha-1,8-diene

Cas Number:

5989-27-5

Molecular formula:

C10H16

IUPAC Name:

4-isopropenyl-1-methylcyclohexene

Test material form:

liquid

Test animals

Species:

mouse

Strain:

B6C3F1

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories (Portage, USA)
- Age at study initiation: 7-9 weeks
- Weight at study initiation: Males: 23.8-29.5 g; females: 20.2-21.5 g
- Housing: Housed in groups of five in polycarbonate cages
- Diet (e.g. ad libitum): Purina Lab Blox (Chesapeake Feed Co., Beltsville, USA) or NIH 07 Rat and
Mouse Ration (Zeigler Bros., Inc., Gardners, PA, USA), ad libitum
- Water (e.g. ad libitum): Automatic watering system (Edstrom Industries, Waterford, USA), ad libitum
- Acclimation period: 18 days

ENVIRONMENTAL CONDITIONS
- Temperature (°F): 60-82 °F
- Humidity (%): 35-80%
- Air changes (per hour): 12-15/hour
- Photoperiod (hours dark / hours light): 12 hours dark / 12 hours light

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: Appropriate amount of test substance was weighed and mixed with corn oil by shaking in a volumetric flask.
VEHICLE
- Amount of vehicle (if gavage): 10 mL/kg bw

Details on mating procedure:

Not applicable

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Apparatus: Periodic analysis for d-limonene in dose preparations was determined by extraction with methanol followed by gas chromatographic analysis of the extract with a 6-foot 3% OV-17 glass column, a nitrogen carrier at a flow rate of 30 mL/min, and a flame ionization detector.
- Sampling frequency: Once
- Results: 101-109% of the target concentrations

Duration of treatment / exposure:

13 weeks

Frequency of treatment:

Once per day; 5 days/week

Details on study schedule:

Not applicable

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

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

Doses / concentrations 2

Dose / conc.:

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

Doses / concentrations 3

Dose / conc.:

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

Doses / concentrations 4

Dose / conc.:

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

Doses / concentrations 5

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

Doses / concentrations 6

Dose / conc.:

2 000 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Doses were selected based on the mortalities observed at 3300 and 6600 mg/kg bw/day during a 16 day subacute toxicity study.
- Rationale for animal assignment (if not random): Random

Positive control:

None

Examinations

Parental animals: Observations and examinations:

CLINICAL OBSERVATIONS: Yes
- Time schedule: Twice daily

BODY WEIGHT: Yes
- Time schedule for examinations: Initially and once per week thereafter

Oestrous cyclicity (parental animals):

Not applicable

Sperm parameters (parental animals):

Not applicable

Litter observations:

Not applicable

Postmortem examinations (parental animals):

GROSS PATHOLOGY: Yes; necropsy performed on all animals
HISTOPATHOLOGY: Yes; performed on all vehicle control and high dose animals and all female rats in the 1200 mg/kg bw/day group. Tissues examined include: adrenal glands, brain, colon, esophagus, eyes (if grossly abnormal), femur or sternebrae or vertebrae including marrow, gross lesions and tissue masses with regional lymph nodes, heart, kidneys, liver, lungs and mainstem bronchi, mammary gland, mandibular or mesenteric lymph nodes, pancreas, parathyroids, pituitary gland, prostate/testes or ovaries/uterus, salivary glands, small intestine, spinal cord (if neurologic signs present), spleen, stomach, thymus, thyroid gland, trachea, and urinary bladder.

Postmortem examinations (offspring):

Not applicable

Statistics:

No data

Reproductive indices:

Not applicable

Offspring viability indices:

Not applicable

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Rough hair coats and decreased activity were observed at 1000 and 2000 mg/kg bw/day.

Mortality:

mortality observed, treatment-related

Description (incidence):

- 1/10 male and 2/10 females died at 2000 mg/kg bw/day
- 1/10 female died at 500 mg/kg bw/day
- Several animals in other groups died as a result of gavage error.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Final mean bodyweights of mice that received 1000 or 2000 mg/kg bw/day were 10% lower than that of the vehicle controls for males and 2% lower for females

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Histopathological findings: non-neoplastic:

effects observed, non-treatment-related

Description (incidence and severity):

An alveolar cell adenoma was observed in the lung of 1/10 females that received 2000 mg/kg bw/day.

Histopathological findings: neoplastic:

not examined

Other effects:

not examined

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

not examined

Reproductive performance:

not examined

Effect levels (P0)

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male

Basis for effect level:

clinical signs

mortality

body weight and weight gain

Target system / organ toxicity (P0)

Key result

Critical effects observed:

no

Results: F1 generation

Effect levels (F1)

Remarks on result:

not measured/tested

Target system / organ toxicity (F1)

Critical effects observed:

not specified

Overall reproductive toxicity

Key result

Reproductive effects observed:

no

Applicant's summary and conclusion

Conclusions:

The NOAEL was considered to be 500 mg/kg bw/day. The LOAEL was considered to be 1000 mg/kg bw/day for both female and male mice, based on observation of clinical signs in both sexes and decreased bodyweights in males. No effects in reproductive organs were observed at either the macroscopic or the microscopic levels therefore no effects on reproductive performance are anticipated.

Executive summary:

In a 13-week subchronic toxicity study performed similarly to OECD Guideline 408 and in compliance with GLP, d-limonene was administered through gavage to groups of 10 B6C3F1 mice/sex/dose mixed in corn oil at dose levels of 0, 125, 250, 500, 1000 or 2000 mg/kg bw/day for 13 weeks (5 days/week). Animals were observed twice daily for clinical signs of toxicity and bodyweights were recorded weekly.

Necropsy performed on all animals and microscopic examination of specified tissues was performed for all control and high dose animals scheduled to be killed at the end of the treatment period.

One of 10 males and 2/10 females that received 2000 mg/kg bw/day and 1/10 females that received 500 mg/kg bw/day died before the end of the studies. Several animals in other groups died as a result of gavage error. Clinical signs of rough hair coats and decreased activity were observed at the two highest doses. Final mean bodyweights of mice that received 1000 or 2000 mg/kg bw/day were 10% lower than

that of the vehicle controls for males and 2% lower for females. An alveolar cell adenoma was observed in the lung of 1/10 females that received 2000 mg/kg bw/day.

Therefore, the NOAEL was considered to be 500 mg/kg bw/day. The LOAEL was considered to be 1000 mg/kg bw/day for both female and male mice, based on observation of clinical signs in both sexes and decreased bodyweights in males. No effects in reproductive organs were observed at either the macroscopic or the microscopic levels therefore no effects on reproductive performance are anticipated.