A mixture of: cis-tetrahydro-2-isobutyl-4-methylpyran-4-ol; trans-tetrahydro-2-isobutyl-4-methylpyran-4-ol

Repeated dose toxicity: dermal

Administrative data

Endpoint:

sub-chronic toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2015

Report date:

2015

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 411 (Subchronic Dermal Toxicity: 90-Day Study)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.28 (Sub-Chronic Dermal Toxicity Test: 90-Day Repeated Dermal Dose Study Using Rodent Species)

GLP compliance:

yes (incl. QA statement)

Remarks:

BASF SE

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

A mixture of: cis-tetrahydro-2-isobutyl-4-methylpyran-4-ol; trans-tetrahydro-2-isobutyl-4-methylpyran-4-ol

EC Number:

405-040-6

EC Name:

A mixture of: cis-tetrahydro-2-isobutyl-4-methylpyran-4-ol; trans-tetrahydro-2-isobutyl-4-methylpyran-4-ol

Cas Number:

63500-71-0

Molecular formula:

C10 H20 O2

IUPAC Name:

4-methyl-2-(2-methylpropyl)oxan-4-ol

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): Pyranol
- Physical state: liquid / colorless, clear
- Analytical purity: 99.6 corr. area %
- Impurities (identity and concentrations):
- Composition of test material, percentage of components:
- Isomers composition: mixture of two diasteromers
- Homogenicity: given (visually)
- Test substance No.: 09/0639-4
- Lot/batch No.: 00027577L0
- Date of production: 29 Oct 2013
- Expiration date of the lot/batch:
- Stability under test conditions: 29 Oct 2015, stability under storage conditions over the test periond was guaranteed by the sponsor
- Storage condition of test material: ambient (room temperature)

Test animals

Species:

rat

Strain:

other: Crl:WI(HAN)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services GmbH, Sulzfeld, Germany
- Age at study initiation: 63 ± 1 days
- Weight at study initiation:
- Fasting period before study:
- Housing: animals were housed individually in makrolon cages, type M III with dust-free wooden bedding
- Diet: ground Kliba mouse/rat maintenance diat “GLP”, meal ad libitum
- Water: ad libitum
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Type of coverage:

semiocclusive

Vehicle:

corn oil

Details on exposure:

TEST SITE
- Area of exposure: intact clipped skin of the back (dorsal and dorsolateral areas of the trunk)
- % coverage: not less than 10% of the body surface
- Type of wrap if used: semiocclusive dessing (4 layers of absorbent gauze and strech bandage)
- Time intervals for shavings or clipplings: at least once a week (depending on hair growth)

REMOVAL OF TEST SUBSTANCE
- Washing: with lukewarm water
- Time after start of exposure: after removal of the dressing (at least 6 hours)

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 4 ml/kg bw in corn oil

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

at least 6 hours daily

Frequency of treatment:

5 days per week (once daily)

Doses / concentrations

Remarks:

Doses / Concentrations:
100, 300 and 1000 mg/kg bw/d
Basis:
nominal per unit body weight

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice on workdays, daily on weekends/public holidays

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once before beginning of the applicationperiod (day 0) and subsequently once a week

DERMAL IRRITATION: Yes
- Time schedule for examinations: once each workday (immediately before application)

BODY WEIGHT: Yes
- Time schedule for examinations: before the start of application peroid, on day 0 and thereafter at weekly intervals

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes

WATER CONSUMPTION: Yes
- Time schedule for examinations: daily by visual inspection

OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: before administration and toward the end of the application peroid
- Dose groups that were examined: control and high dose (other dose groups will be examined only if there is a striking discrepancy between the highest dose group and the control group)

HAEMATOLOGY: Yes
- Time schedule for collection of blood: day 92 (males) and day 93 (females)
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes (fasting peroid of about 16 to 20 hours)
- Blood was taken from the retro-bulbar venous plexus.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: day 92 (males) and day 93 (females)
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes (fasting peroid of about 16 to 20 hours)
- Blood was taken from the retro-bulbar venous plexus.

URINALYSIS: Yes

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: once towards the end of treatment
- Dose groups that were examined: all animals
- Battery of functions tested: Home cage observation, open field observation, Sensory motor tests/ reflexes, Motor activity

Sacrifice and pathology:

All animals were sacrified by decapitation under isoflurane anesthesia.

GROSS PATHOLOGY: Yes
Anesthetized animals, adrenal glands, kidneys, liver, tested and thyroid glands were weighed.

HISTOPATHOLOGY: Yes
The following organs or tissues will be fixed in 4% formaldehyde solution or in modified Davidson's solution:
All gross lesions, Adrenal glands, Aorta, Bane marrow (femur), Brain, Cecum, Cervix, Coagulating gland, Colon, Duodenum, Epididymides, Esophagus, Extraorbital lacrimal glands, Eyes with optic nerve (modified Davidson's solution), Femur with knee joint, Harderian gland, Heart, Ileum, Jejunum (with Peyer's patches), Kidneys, Larynx, Liver, Lung, Lymph nodes (mesenteric and axillary lymph nodes), Mammary gland (male+female), Nose (nasal cavity), Ovaries, Oviducts, Pancreas, Parathyroid glands, Pharynx, Pituitary gland, Prostate, Rectum, Salivary glands (mandibular and sublingual glands), Seminal vesicles, Sciatic nerve, Skeletal muscle, Skin treated, Skin untreated, Spinal cord (cervical, thoracic and lumbar cord), Spleen, Sternum with marrow, Stomach (forestomach and glandular stomach), Testes, Thymus, Thyroid glands, Trachea, Urinary bladder, Uterus, Vagina

Statistics:

food consumption, body weight, body weight change: DUNNETT's test
Feces, rearing, grip strength forelimbs, grip strength hindlimbs, foot-splay test, motor activity: KRUSKAL-WALLIS test and WILCOXON-test

Results and discussion

Results of examinations

Details on results:

CLINICAL SIGNS AND MORTALITY
No animal died during the administration period.
Some male and female animals showed slight erythema, erosion and scales. These finding are attributed to the irritating properties of the test substance. No other abnormal clinical signs were observed.

BODY WEIGHT AND WEIGHT GAIN
Mean body weight change in females of test group 3 (1000 mg/kg bw/d) was significant higher on study day 0-14.

FOOD CONSUMPTION
No test substance-related observations were noted.

WATER CONSUMPTION
No test substance-related observations were noted.

OPHTHALMOSCOPIC EXAMINATION
No test substance-related observations were noted. All findings were assessed as being incidental in nature since they occurred in individual animals only and did not show a dose-response relationship.

HAEMATOLOGY
No treatment-related changes among haematological parameters were observed.
In males of test group 2 (300 mg/kg bw/d) staticical significant decreases in the total values of white blood cells, neutrophiles, lymphocytes and monocytes were observed. These alterations were not dose-dependent and therefore they were regarded as incidental and not treatment-related.

CLINICAL CHEMISTRY
No treatment-related changes among clinical chemistry parameters were observed.
In females of test group 2 (300 mg/kg bw/d) and 3 (1000 mg/kg bw/d) glucose values were silghtly but statistically significant increased (4.99 and 4.72 mmol/l) compared to controls (5.36 mmol/l). Although the increases in glucose were statistically significantly different to the control value and showed a dose-response relationship, these isolated findings were assessed as being fortuitous since similar increases were not observed in the males.

URINALYSIS
No treatment-related, adverse changes among urinalysis parameters were observed.

NEUROBEHAVIOUR
Deviations from "zero values" were obtained in several animals. However, as most findings were equally distributed between test-substance treated groups and controls, were without a dose-response relationship or occurred in single animals only, these observations were considered to have been incidental.

ORGAN WEIGHTS
No effects on mean absolute and relative organ weights were observed.

GROSS PATHOLOGY
All findings occurred individually. They were considered to be incidental or spontaneous in origin and without any relation to treatment.

HISTOPATHOLOGY
All findings occurred individually. They were considered to be incidental or spontaneous in origin and without any relation to treatment.

Effect levels

Dose descriptor:

NOAEL

Effect level:

1 000 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no treatment-related, adverse effects were observed

Target system / organ toxicity

Critical effects observed:

not specified