Dodecanoic acid, ester with oxybis[propanediol]

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP-Guideline study, tested with the source substance 2,3-Dihydroxypropyl 9-cis-octadecenoate ( CAS No. 111-03-5). According to the ECHA guidance document “Practical guide 6: How to report read-across and categories (March 2010)”, the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2,3-dihydroxypropyl oleate

EC Number:

203-827-7

EC Name:

2,3-dihydroxypropyl oleate

Cas Number:

111-03-5

IUPAC Name:

2,3-dihydroxypropyl octadec-9-enoate

Details on test material:

- Name of test material (as cited in study report): Glycerol oleate; 2,3-Dihydroxypropyl 9-cis-octadecenoate
- Physical state: light yellow pellet
- Analytical purity: 99.93%
- Storage condition of test material: in the dark and cool

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories Japan Inc., Yokohama, Japan
- Age at study initiation: 10 weeks
- Weight at study initiation: 352-426 g (males), 192-249 g (females)
- Housing: animals were housed individually in stainless steel cages
- Diet: ad libtum
- Water: ad libitum
- Acclimation period: 11 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22.1-23.2
- Humidity (%): 48-61
- Air changes (per hr): > 10
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Aliquots of the dosing solution (prepared in corn oil) corresponding to the amount of daily administration were stored at 2-6 °C in the dard. The stability of the dosing solution was 7 days in a refrigerator and one day at room temperature. Thus, the dosing solutions were used within 7 days.

VEHICLE
- Justification for use and choice of vehicle: the test substance showed low solubility in water.
- Amount of vehicle (if gavage): 5 mL/kg
- Lot/batch no. (if required): V4N3566

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

Males: 42 days (14 days before mating and 28 days thereafter)
Females: 42-52 days (from 14 days before mating to Day 4 of lactation)
Satellite males and females: 42 days and 14 days post-exposure observation period

Frequency of treatment:

once daily, 7 days/week

Doses / concentrations

Remarks:

Doses / Concentrations:
100, 300 and 1000 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

12 males and females (including 5 males of the control and high-dose group as recovery group )
5 additional females (in satellite control and high-dose group)

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:
Prior to the main study, two dose range finding studies were performed. In the first study, 2000 mg/kg bw of test substance were administered for 3 days in male and female rats. No abnormalities were found in general condition and body weight. In the second study, dose levels of 100, 300 and 1000 mg/kg bw/day were administered for 14 days. No abnormalities of general condition, body weight, food consumption, haematological findings, blood biochemical findings, gross pathology and organ wight were found. Therefore, 1000 mg/kg bw/day was selected as the highest dose level for the main study.
- Post-exposure recovery period in satellite groups: 14 days

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: prior to the first administration and weekly thereafter

BODY WEIGHT: Yes
- Time schedule for examinations:
Males: prior to administration on Day 1 and on Day 7, 14, 21, 28, 35 and 42 (before sacrifice)
Females: prior to administration on Day 1 and on Day 7 and 14, during pregnancy on Day 0, 7 14 and 21, during lactation on Days 0 and 4 (before sacrifice)
Satellite males and females: prior to administration on Day 1 and on Day 7, 14, 21, 28, 35, 42, 49 (Day 7 of recovery period) and 56 (Day 14 of recovery period, before sacrifice)

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

HAEMATOLOGY: Yes
- Time schedule for collection of blood: one day after last application
- Anaesthetic used for blood collection: Yes (ether)
- Animals fasted: Yes
- How many animals: 5 per group
- Parameters checked: red blood cell count (RBC), Haemoglobin, Haematocrit, mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), mean cell volume (MCV), Platelets, Reticulocytes, PT, APTT, white blood cell count (WBC), Differential leukocytes: Lymphocytes, Neutrophils, Eosinophils, Basophils, Monocytes

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: one day after last application
- Animals fasted: Yes
- How many animals: 5 per group
- Parameters checked: AST, ALT, ALP, γ-GTP, T-protein, Albumin, A/G, T-bilirubin, BUN, Creatinine, Glucose, T-cholesterol, Triglyceride, Na, K, Cl, Ca, P, LDH, choline esterase

URINALYSIS: Yes (males)
- Time schedule for collection of urine: Day 37 during administration period or Day 9 during recovery period
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Parameters checked: colour, cloudiness, water consumed, volume, specific gravity, Na, K, pH, Protein, Glucose, Ketone body, Bilirubin, Occult blood, Urobilinogen, Epithelial cells, Erythrocytes, Leukocytes, Casts, Crystals, Fat

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:
Males: on Week 6 (administration period)
Females: on Week 6 (administration period)
Males and females of satellite groups: on Week 6 of the administration period and on Week 2 of the recovery period
- Dose groups that were examined: all
- Battery of functions tested: hearing reaction, eye sight reaction, sense of touch reaction, pain reaction, pupil reflex, pinna reflex, ipsilateral flexor reaction, eyelid reflex, righting reflex

Sacrifice and pathology:

GROSS PATHOLOGY: Yes, body surface, mucous membranes and internal organs

HISTOPATHOLOGY: Yes, brain, pituitary, thyroid, thymus, lung trachea (after liquid immersion fixation), stomach, intestines, heart, liver, spleen, kidney, adrenal gland, bladder, testis, epididymis, prostate, seminal vesicles, ovaries, uterus, spinal cord (cervical, thoracic, lumbar), sciatic nerve, bone marrow (femur), lymph nodes (cervical lymph node, mesenteric lymph nodes), mammary gland, and other gross abnormalities
Spermatogenic cycle (Stage II, III, V, VII, and XII) was also investigated.

SACRIFICE
- Males: Day 43
- Females: Day 5 of lactation
- Females (unsuccessful mating): Day 53
- Females (mated but non-pregnant): Day 5 after scheduled delivery
- Satellite males and females: Day 15 of the recovery period

Other examinations:

ORGAN WEIGHT: brain, liver, kidney, spleen, heart, thymus, thyroid, pituitary, adrenal, testis, seminal vesicle, epididymis

Statistics:

ANOVA, Barlettm Kruskal-Willis, Dunnett test, F-test, Studen t-test, Aspin-Welch t-test, Mann-Whitney U-test, Fisher's exact test

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

1000 mg/kg bw/day males (satellite group): significant increase, non-adverse

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

1000 mg/kg bw/day females (satellite group): significant increase on Day 14, non-adverse

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

100 and 300 mg/kg bw/day (males): decrease in APTT, non-adverse

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

300 and 1000 mg/kg bw/day (females): significant increase inorganic P, non-adverse; 1000 mg/kg bw/day females (satellite group): significant increase in choline esterase, non-adverse

Urinalysis findings:

no effects observed

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

100 mg/kg bw/day: significant decrease in absolute weight of seminal vesicles in male and significant decrease in relative weight of spleen in females, non-adverse

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

300 mg/kg bw/day females: mass in subcutis in one animal, not treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

effects observed, treatment-related

Description (incidence and severity):

300 mg/kg bw/day females: benign fibroadenoma of the mammary gland in one animal, not treatment-related

Details on results:

CLINICAL SIGNS AND MORTALITY
No mortalities and no clinical signs of toxicity were observed.

BODY WEIGHT AND WEIGHT GAIN
No changes in body weight and weight gain were observed during the treatment period.
During the recovery period, in males of the high-dose group a significant increase in body weight was noted, probably due to a tendency of the control group animals to lose body weight. One male in the control group showed a significant decrease in body weight during the recovery period. However, no other abnormalities were observed in this male.

FOOD CONSUMPTION
No differences in food consumption were observed during the administration period in the test groups.
In satellite females of the high-dose, a significant increase in food consumption was found on Day 14 of administration. However, the finding was regarded as incidental and not substance-related, since the food consumption of the corresponding control group was relatively low on the respective day.

HAEMATOLOGY
No changes in the observed parameters were noted. However, a significant decrease in APTT ( Activated Partial Thromboplastin Time) was observed in males of the low and mid-dose groups in comparison to the control group. The finding was considered not to be of toxicological relevance; no dose-relationship was observed and the value was still within the reference range.

CLINICAL CHEMISTRY
A significant decrease in inorganic phosphate was observed in females of the low and high-dose group. However, this change was not regarded as test substance-related, since no dose-relationship was observed and most of the individual data were within the reference ranges. Furthermore, choline esterase was increased in females of the high dose group after the recovery period but was still was within the reference range. Since the difference was only slight and no change was observed after the administration period, the effect was considered not to be substance-related.

URINALYSIS
No significant changes in urine parameters were found during the administration and recovery periods.

NEUROBEHAVIOUR
No abnormalities were observed for the sensory/reflex function, landing foot, grip strength and motor activity during the administration period. During the recovery period, motor activity increased from 0 to 60 min, but not from 0 to 30 min in high dose females. This effect was not considered to be substance-related since the observed difference was slight and no change was observed during and after the administration period.

ORGAN WEIGHTS
In males of the low dose group, after the administration period a significant decrease in the absolute weight of seminal vesicles was observed. Furthermore, a significant decrease in the relative spleen weight of females in the low dose group was apparent. These changes were considered not to be compound-related as no corresponding findings were apparent in the histopathological examination and no dose-relationship was observed.
After the recovery period, the relative weight of pituitary in males of the high dose group was significantly decreased. In addition, high dose females showed a decrease in the relative thyroid weight. These effects were also not considered to be substance-related because no abnormalities were reported regarding these organs after the administration period.

GROSS PATHOLOGY
Gross pathology showed no substance-related changes. No differences were found in breeding pairs which were not successful at mating and in those which were successful at mating but not pregnant.
After the administration period, in one male of the control reddish thymus was noted and in one female of the mid-dose group subcutis mass was found. After the recovery period, larger spleen and capsular thickening in spleen was found in one male and reddish area in thymus was observed in one female of the high-dose group.

HISTOPATHOLOGY: NON-NEOPLASTIC
No test substance-related changes were observed in histopathological examinations.
Furthermore, no differences were found regarding spermatogenic cycle.
In male control animals, accumulation of foam cell, microgranuloma in the liver, solitary cyst in the kidnes and haemorrhage of the thymus were observed with low incidence. In female animals of the control group, artery mineralization of the lung, hyaline cast and cortex fibrosis of the kidney were apparent with low incidence in control animals only. Both in the high-dose group and in the control group, myocardial degeneration/fibrosis, extramedullary haematopoiesis of the spleen, foam cell accumulation of the lung, and focal liver necrosis, were found with low incidence in control and test groups. In all males of the high-dose and control group, hyaline droplet of proximal tubular epithelium in the kidney was found. Furthermore, in all males and females of the control and high dose group, brown deposit pigment and extramedullary haematopoiesis in spleen were found without differences between control and test group.
Incidental not substance-related findings of lymphocyte interstitium infiltration in prostate were found in one male of the high-dose group and interstitial focal inflammation in the lung and focal necrosis in the liver of one female of the high dose group were observed.
No abnormalities were found in the uterus and ovaries in the non-pregnant females and the unsuccessful copulation females of the control and high-dose groups, respectively. Degeneration of seminiferous tubules of testis, decrease in sperm and atrophy in prostate was observed in one control male only.

HISTOPATHOLOGY: NEOPLASTIC
In the mid-dose group, mass on abdomen was found in one female after 40 days of administration. This subcutaneous tumour of the mammary gland was a benign fibroadenoma and generated naturally and was therefore not considered to be substance related.

Effect levels

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: overall effects

Target system / organ toxicity

Critical effects observed:

not specified