4-Octanol, 3-amino-

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted as per OECD TG 414, US EPA OPPTS 870.3700, EU Method B.31, JMAFF, Guideline 2-1-18 and in accordance with the Principles of Good Laboratory Practice (GLP).

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.31 (Prenatal Developmental Toxicity Study)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.3700 (Prenatal Developmental Toxicity Study)

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: JMAFF, Guideline 2-1-18, Teratogenicity Study

Deviations:

no

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:

-

EC Number:

482-070-6

EC Name:

-

Cas Number:

1001354-72-8

Molecular formula:

C8-H19-N-O

IUPAC Name:

(3R,4R)-3-aminooctan-4-ol; (3R,4S)-3-aminooctan-4-ol; (3S,4R)-3-aminooctan-4-ol; (3S,4S)-3-aminooctan-4-ol

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report): 3-amino-4-octanol
- Analytical purity: The purity of the test material was determined to be 98.55% +/- 0.08% on an anhydrous basis by gas chromatography with identification by proton and carbon-13 nuclear magnetic resonance and gas chromatography mass spectrometry
- Lot/batch No.: lot # CEC-200803388-4

Test animals

Species:

rat

Strain:

other: Crl:CD(SD)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (Portage, Michigan)
- Age at study initiation: sexually mature adults
- Weight at study initiation: approximately 200-250 grams
- Fasting period before study: not applicable
- Housing: individually housed in stainless steel, solid bottom cages
- Diet (e.g. ad libitum): ad libitum, animals were provided LabDiet Certified Rodent Diet #5002 (PMI Nutrition International, St. Louis, Missouri) in meal form
- Water (e.g. ad libitum): ad libitum, drinking water obtained from the municipal water source through a pressure activated lixit valve-type watering system
- Acclimation period: for at least 4 days prior to dosing.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22°C with a tolerance of ± 1°C (and a maximum permissible excursion of ± 3°C)
- Humidity (%): 40-70%
- Air changes (per hr): 10-15 times/hour (average)
- Photoperiod (hrs dark / hrs light): 12 hours light/dark cycle

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

propylene glycol

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: All dosing solutions were prepared by mixing the test material in propylene glycol at concentrations of 0, 2.5, 10, or 25 mg/ml and administered at a dose volume of 6 ml/kg body weight to achieve the targeted dose levels. Dose solutions were not corrected for purity. Dose volumes were adjusted every day based on individual body weights. The control rats were dosed with propylene glycol at 6 ml/kg body weight.

VEHICLE
- Justification for use and choice of vehicle (if other than water): recommended by various regulatory agencies
- Concentration in vehicle: All dosing solutions were prepared by mixing the test material in propylene glycol at concentrations of 0, 2.5, 10, or 25 mg/ml and administered at a dose volume of 6 ml/kg body weight to achieve the targeted dose levels
- Amount of vehicle (if gavage): All dosing solutions were prepared by mixing the test material in propylene glycol at concentrations of 0, 2.5, 10, or 25 mg/ml and administered at a dose volume of 6 ml/kg body weight to achieve the targeted dose levels

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analysis of all dosing solutions from the first mix revealed mean concentrations of 3-amino-4-octanol ranging from 97.2 to 99.7% of targeted concentrations. Analysis of aliquots for the low- and high-dose solutions indicated that the test material was homogeneously distributed based on standard deviations of 1.5 and 4.1%, respectively.

Details on mating procedure:

- Impregnation procedure: purchased timed pregnant

Duration of treatment / exposure:

days 6-20 of gestation

Frequency of treatment:

daily during days 6-20 of gestation

Duration of test:

5-6 months

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
15 mg/kg/day
Basis:
nominal conc.

Doses / concentrations 2

Remarks:

Doses / Concentrations:
60 mg/kg/day
Basis:
nominal conc.

Doses / concentrations 3

Remarks:

Doses / Concentrations:
150 mg/kg/day
Basis:
nominal conc.

No. of animals per sex per dose:

24 rats/dose level

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: on the basis of an acute oral study (estimated LD50 - 550 mg/kg) and a range-finding study, where five Crl:CD(SD) rats/sex were administered 3-amino-4–octanol in propylene glycol at dose levels of 0, 50, 100, 250, 350, 450 mg/kg/day by daily gavage, for up to 14 days at a dose volume of 6 ml/kg body weight. Dose levels of 250 mg/kg/day and above exceeded the maximum tolerated dose, as determined by clinical observations of noisy, labored respiration with or without mouth breathing in several animals in these three dose groups. Necropsy of the moribund animals revealed decreased amount of fat, darkened lungs, decreased ingesta and gas within the gastrointestinal tract. These findings were attributed to the physical and chemical properties of the test material causing irritation of the lungs likely from aspiration of the test material. Due to the prevalence and incidence, these were not considered gavage errors, but instead dose limiting characteristics of the 3-amino-4-octanol.
Based on these results of the range-finding study, in the OECD 421 study, 12 Crl:CD(SD) rats/sex/group were administered 0, 15, 60, or 150 mg/kg/day 3-amino-4-octanol, in propylene glycol by gavage, at a dose volume of 6 ml/kg body weight for two weeks pre-breeding, through gestation, and up to lactation day 4 (females) or 32 test days (males). Gavage administration of 3-amino-4-octanol at dose levels up to, and including, 150 mg/kg/day produced no indication of reproductive toxicity at any dose level. There were no effects on prenatal/early neonatal growth and survival of the offspring. Based on these results, the no-observed- effect level (NOEL) for systemic and reproductive toxicity was 150 mg/kg/day, the highest dose level tested.
In a 90-day oral gavage toxicity study, 3-amino-4-octanol was administered by gavage, at 6 ml/kg body weight dose volume in propylene glycol vehicle, to groups of ten male and ten female Crl:CD(SD) rats at dose levels of 0, 15, 60, or 150 mg/kg body weight/day and to groups of ten male Crl:WI(Han) rats at dose levels of 0 or 150 mg/kg body weight/day for at least 90 days to evaluate the potential for systemic toxicity. There were no treatment-related effects in clinical signs, functional tests, body weights, feed consumption, ophthalmic, hematology, prothrombin time, or clinical chemistry parameters in Crl:CD(SD) rats of either sex. Male Crl:WI(Han) rats had treatment-related decreases in body weight, body weight gain, and feed consumption with treatment-related clinical observations including reflux of test material, noisy respiration, slow respiration, labored respiration (without mouth breathing), and/or blood coming
from the nasal cavity in the 150 mg/kg/day, which were associated with irritancy of the test material. There were no treatment-related epididymal sperm parameters (motility, counts, or morphology), gross or histopathologic observations and no toxicologically significant effects in urinalysis parameters or organ weight effects in the Crl:CD(SD) or Crl:WI(Han) rats.
The no-observed-effect level (NOEL) for male reproductive effects in either strain was 150 mg/kg/day, the highest dose level tested. The no-observed-adverse-effect level (NOAEL) for Crl:CD(SD) rats of either sex was 150 mg/kg/day 3-amino-4-octanol

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Twice daily approximately at the same time each day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Clinical observations were conducted on all animals at least once daily and included a careful, hand-held examination of the animal with an evaluation of abnormalities in the eyes, urine, feces, gastrointestinal tract, extremities, movement, posture, reproductive system, respiration, skin/hair-coat, and mucous membranes, as well as an assessment of general behavior, injuries or palpable mass/swellings

BODY WEIGHT: Yes
- Time schedule for examinations: Body weights were recorded on GD 0 (by the supplier) and daily during GD 6 through 21.

FOOD CONSUMPTION: Yes
- Feed consumption was recorded and statistically analyzed for all animals every three days from GD 3-21 by weighing feed containers at the start and end of a measurement cycle (3-6, 6-9, 9-12, 12-15, 15-18, 18-21)

WATER CONSUMPTION: No

POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day 21
- Organs examined: On day GD 21, all surviving females (not fasted) were euthanized by carbon dioxide inhalation and a limited gross pathologic examination (necropsy) was performed. The sequence of the maternal necropsies was counterbalanced across groups (e.g., control, high, middle, low) to control for potential confounding influences of timing on fetal growth and skeletal ossification.
The maternal necropsy included an examination of the external tissues and all orifices. The skin was reflected from the carcass, the thoracic and abdominal
cavities were opened and the viscera were examined. The stomach, liver, and kidneys were dissected from the carcass and were incised. Any obvious gross
pathologic alterations were recorded, and the weight of the liver, kidneys, and gravid uterus were recorded. The ratios of liver and kidney weights to terminal
body weight were calculated. Representative sections of liver, kidneys, and gross lesions were preserved in neutral, phosphate-buffered 10% formalin. Microscopic examination of tissues was not conducted. Transponders were removed and placed in jars with the tissues.

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: Yes
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
- A detailed examination of the reproductive tract was performed and the number and position of implantations, viable fetuses, dead fetuses, and resorptions were recorded. Resorptions were classified as either “early” or “late” based on the presence (late resorption) or absence (early resorption) of grossly recognizable embryonic/fetal form, while a “dead fetus” indicated a very recent death as evidenced by a lack of external degenerative changes. For females with one or
more viable fetuses, the number of ovarian corpora lutea was counted. The uteri of females lacking visible implantations was stained with a 10% aqueous solution of ammonium sulfide and examined for evidence of early resorptions in order to verify pregnancy status.

Fetal examinations:

- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: half per litter
- Skeletal examinations: Yes: half per litter
- Head examinations: Yes: half per litter
- The sex of all fetuses was recorded and the body weight of all viable fetuses was recorded. All fetuses were given an external examination that included
observations on body proportions, the head and face (including closure of the palate), abdomen, spine, extremities, genitalia, rectum and tail. All viable fetuses were euthanized by sublingual oral administration of sodium pentobarbital solution. Approximately one half of all the fetuses in each litter were chosen randomly via computer for visceral examination conducted by dissection under a low power stereomicroscope for evidence of visceral alterations. The visceral examination included observation of the thymus, trachea, esophagus, lungs, great vessels, heart (external and internal), liver, gastrointestinal tract, pancreas, spleen, kidney (sectioned), adrenal glands, ureters, bladder and reproductive organs. The heads of these fetuses were removed, placed in Bouin’s fixative and serially sectioned to allow for inspection of the eyes, brain, nasal passages and tongue. The remaining fetuses not selected for visceral examination were skinned, eviscerated, preserved in alcohol and double stained with Alcian Blue and Alizarin Red S for cartilage and bone. A thorough evaluation of the fetal skeleton was conducted on the remaining fetuses not selected for visceral examination.

Statistics:

Standard statistical methods were employed

Indices:

Pre- and post-implantation loss

Historical control data:

refer to attachment

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:yes

Details on maternal toxic effects:
- In-life Observations - Examinations performed on all animals revealed no treatment-related findings.
- Body weights/body weight gains - Although body weights in the treated groups were similar to controls, body weight gain in animals given 60 and 150 mg/kg/day from GD 6-9 was decreased in by 33.6 and 50.4%, respectively. There were no treatment-related effects on body weight gain in the 15 mg/kg/day dose level.
- Food consumption - Animals given 60 and 150 mg/kg/day had treatment-related decreases in feed consumption from GD 9-12 and 6-12, respectively, (ranging from 8.6 to 19.1%) relative to controls. There were no treatment-related effects on feed consumption in the 15 mg/kg/day dose level.
- Organ weights - There were no treatment-related differences in any of the measured parameters for any treated groups when compared to controls.
- Gross pathology - There were no treatment-related gross pathologic observations. The small number of gross pathologic observations either occurred at low frequencies and/or lacked a dose-response relationship.

Effect levels (maternal animals)

1

Dose descriptor:

NOEL

Effect level:

15 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

2

Dose descriptor:

NOEL

Effect level:

150 mg/kg bw/day (nominal)

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
- Reproductive parameters - There were no treatment-related effects on pregnancy rates, resorption rates, litter size, numbers of corpora lutea or implantations, percent pre-implantation loss, percent postimplantation loss, fetal sex ratios, fetal body weight or gravid uterine weights in any treatment group.
- Fetal examinations - There were no treatment-related differences in the incidence of any fetal alteration in any treatment group compared to controls. Malformations or variations observed in fetuses from dams administered 3-amino-4-octanol either occurred at low frequencies and/or lacked a dose-response relationship.
- External examination - There were no treatment-related external malformations or variations in any treatment group. Incidental findings bearing no relationship to treatment included subdermal hematoma and slight forelimb flexure (variations), and forelimb flexure (malformation). These observations occurred at low frequencies and lacked a dose response relationship.
- Craniofacial examination - There were no treatment-related external malformations or variations in any treatment group. Incidental findings bearing no relationship to treatment included dilated perinasal area (variation) and hydrocephaly (malformation).
- Visceral examination - There were no treatment-related visceral malformations or variations in any treatment group. Incidental findings bearing no relationship to treatment included enlarged atrium, double carotid artery, missing caudal lung lobe, discolored liver, torsion strangulation of the liver, bifurcated renal vein, and convoluted ureter in individual fetuses. These observations occurred at low frequencies and/or lacked a dose-response relationship. In addition, there was a single fetus in the high-dose group with ventricular septal defect, ventricular double outlet, and situs inversus. Although this fetus was in the high-dose group, the findings were deemed spurious and unrelated to treatment as they were isolated to a single fetus from a single dam.
- Skeletal examination - There were no treatment-related external malformations or variations in any treatment group. Incidental findings bearing no relationship to treatment included delayed ossification (DO) frontal, DO interparietal, DO parietal, DO occipital, DO sternebrae, extra site of ossification sternebrae, DO thoracic centra, class I wavy ribs, class II wavy ribs, calloused ribs, and extra first lumbar rib. These observations occurred at low frequencies, lacked a dose-response relationship, and/or were within the range of recent historical control values.

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Any other information on results incl. tables

None

Applicant's summary and conclusion

Conclusions:

Under the conditions of this study, the no-observed-effect level (NOEL) for maternal toxicity was 15 mg/kg/day, and the developmental toxicity NOEL was 150 mg/kg/day, the highest dose tested.

Executive summary:

The purpose of this study was to evaluate the maternal and developmental toxicity of 3 -amino-4-octanol in Crl:CD(SD) rats following repeated gavage administration. Groups of 24 time-mated female rats were administered 3-amino-4-octanol in propylene glycol

by gavage at dose levels of 0, 15, 60, or 150 mg/kg/day on gestation day (GD) 6 through 20. In-life maternal study parameters included clinical observations, body weight, body weight gain, and feed consumption. On GD 21, all rats were euthanized and examined

for gross pathologic alterations. Liver, kidneys, and gravid uterine weights were recorded, along with the number of corpora lutea, uterine implantations, resorptions and live/dead fetuses. All fetuses were weighed, sexed and examined for external alterations. Approximately one half of the fetuses were examined for visceral and craniofacial alterations, while skeletal examinations were conducted on the remaining fetuses.

Treatment-related effects were limited to decreases in body weight gain and feed consumption in dams given 60 and 150 mg/kg/day. Maternal body weight gain in these groups was decreased by 33.6 and 50.4%, respectively, from GD 6-9. Feed consumption was decreased in dams given 60 and 150 mg/kg/day from GD 9-12 and 6-12, respectively. Body weight gain and feed consumption were similar to controls for the remainder of the study.

Gavage administration of 3-amino-4-octanol at dose levels up to, and including, 150 mg/kg/day produced no treatment-related developmental toxicity.

Therefore, under the conditions of this study, the no-observed-effect level (NOEL) for maternal toxicity was 15 mg/kg/day, and the developmental toxicity NOEL was 150 mg/kg/day, the highest dose tested.