2-octyldodecyl 12-[(1-oxooctadecyl)oxy]octadecanoate

Endpoint summary

Description of key information

Oral: OECD 422, rat, NOAEL ≥ 1000 mg/kg bw/day

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 Dec 2012 - 29 Jan 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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

Species:

rat

Strain:

other: Wistar Hannover RccHan

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories Models, S.L., Barcelona, Spain
- Age at study initiation: 11-12 weeks
- Mean weight at study initiation: males: 312 to 364 g; females: 198 to 219 g
- Fasting period before study: no
- Housing: cages with standard, granulated, softwood Lignocel S8/15 bedding
Pretreatment period: 5 per cage
Mating period: 1 male and 1 female per cage
Postmating: single housing
- Diet: pelleted standard Harlan Teklad 2014C rat/mouse maintenance diet; ad libitum
- Water: tap water; ad libitum
(Analyses of diet and water was performed.)
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-24
- Humidity (%): 30-60
- Photoperiod (hrs dark / hrs light): 12/12

Route of administration:

oral: gavage

Vehicle:

other: 1% methylcellulose+1% Tween 80 in aqueous solution

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 10, 30 and 100 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The concentration of dose formulation was determined in samples taken from the formulation to be administered to Groups 1 to 4 at the start and end of treatment by GC-FID analysis.

Duration of treatment / exposure:

Males: two weeks prior to mating and at least up to and including the day before sacrifice (day 49 of treatment).
Females: two weeks prior to mating and at least up to and including the day before sacrifice (day 4 postpartum).

Frequency of treatment:

Once daily; 7 days/week

Dose / conc.:

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

Dose / conc.:

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

Dose / conc.:

1 000 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: The dose levels were selected based on a dose-range finding toxicity study in rats (Harlan Laboratories Study S40412 14-day Oral (gavage) DRF using dose levels of 100, 500 and 1000 mg/kg bw/day.

Observations and examinations performed and frequency:

MORTALITY AND CLINICAL SIGNS
- Time schedule: at least twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: 2 hours after dosing
- Detailed clinical observations were performed on all test and control group animals before the first exposure to the test item and once weekly thereafter, at least two hours after dosing. Observations were also performed on females with litters on Day 4 postpartum. These observations were performed outside the home cage, in a standard arena, at least two hours after dosing (where applicable) to ensure that any transient effects of treatment are identified.

BODY WEIGHT: Yes
- Time schedule for examinations:
F0 males: twice weekly during the pre-pairing and pairing period and daily during postpairing period.
F0 females: twice weekly during the pre-pairing and pairing period and daily until day 4-5 postpartum.

FOOD CONSUMPTION:
F0 males: once weekly during the pre-pairing period and two weeks of postpairing period.
F0 females: once weekly during the pre-pairing period and days 0-7, 7-14, 14-21 postcoitum and days 1-4 postpartum.
No food consumption was recorded during the mating period.

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION: Yes
F0 males: one week during the pre-pairing and postpairing period.
F0 females: one week during the pre-pairing, postcoitum period and days 1-4 postpartum.
No water consumption was recorded during the remaining periods.

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood:
Males: on day 50
Females: on day 5 postpartum
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes
- How many animals: 5/sex/dose
- Parameters: haemoglobin, erythrocytes, leucocytes, differential blood count (absolute/relative), reticulocytes (count and maturity index), platelets, haematocrit, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, prothrombin time, activated partial thromboplastin time

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood:
Males: on day 50
Females: on day 5 postpartum
- Animals fasted: Yes
- How many animals: 5/sex/dose
- Parameters examined: albumin, globulin, albumin/globulin ratio, bile acids, bilirubin, cholesterol (total), creatinine, glucose, urea, total protein, calcium, chlorid, potassium, sodium, alanine aminotransferase (ALAT), alkaline phosphatase (AP), aspartate aminotransferase (ASAT), triglycerides, creatine kinase, gamma-glutamyl-transferase (gGT), inorganic phosphorus,

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:
Males: the day before sacrifice and at least two hours after dosing.
Females: on day 4 postpartum.
- Dose groups that were examined: all dose groups (5 animals/group)
- Battery of functions tested:
Functional performance test: Grip strength (fore- and hind limbs) and motor activity
Sensory reactivity assessment: Sensory reactivity to different stimuli (e.g. auditory, visual and proprioceptive)

-OTHER: spermatology stage evaluation

Sacrifice and pathology:

GROSS PATHOLOGY: Yes (males on day 50, females on day 5 postpartum)
- Organ weights: epididymes and testicles, adrenal gland, brain, heart, kidney, liver, ovaries, pituitary, spleen, thymus, thyroid and parathyroids, uterus and oviducts
- Fixation: Adrenals, Aorta (thoracic), Bone with bone marrow- (Sternum), Peyer’s patches, Pharynx, Pituitary, Bone marrow smear (femur) (air-dried smear), Brain (cerebrum, cerebellum, medulla/pons), Epididymides (Bouin's solution), Esophagus, Eyes with optic nerve (Davidson’s fixative), Femur (with articular surface), Heart (with papillary muscle), Intestine, large (cecum, colon and rectum), Intestine, small (duodenum, jejunum and
ileum), Kidneys, Larynx, Liver, Lungs, with main bronchi and bronchioles, Lymph nodes (mandibular and mesenteric), Nose (the entire head will be collected), Mammary gland area, Ovaries, Pancreas, Prostate, coagulating gland and seminal vesicles, Salivary glands (mandibular, sublingual and parotid), Sciatic nerve, Skeletal muscle, Skin (abdominal), Spinal cord (cervical, thoracic and lumbar), Spleen, Stomach (glandular and nonglandular), Testes (Bouin's solution), Thymus, Thyroid (incl. parathyroid gland, if possible), Tongue, Trachea, Urinary bladder, Uterus (cervix, corpus and oviducts), Vagina, All gross lesions

HISTOPATHOLOGY: Yes, all organs that were included for fixation (5/sex of control and high dose group)

Statistics:

The following statistical methods were used to analyse food consumption during postpairing period, body weight, clinical laboratory data, organ weights, postnatal development and reproduction data, as well as macroscopic findings:
- The Dunnett-test (many to one t-test) based on a pooled variance estimate was applied if the variables can be assumed to follow a normal distribution for the comparison of the treated groups and the control groups for each sex.
- The Steel-test (many-one rank test) was applied instead of the Dunnett-test when the data cannot be assumed to follow a normal distribution.
- Fisher's exact-test was applied to the macroscopic findings.
- Armitage/Cochran Trend Test [5] for non-neoplastic lesions, if appropriate.
- Bonferroni-test was applied to some reproduction parameters.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

males: increase in bile acids at 300 mg/kg bw/day (non adverse)

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

females: lower left ovary weight at 1000 mg/kg bw/day (non adverse)

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY
No mortality and no relevant clinical signs were observed in males and females. One male and female from the control group and three males and one female at 100 mg/kg showed occasionally up of the product. In addition, male No. 28 at 300 mg/kg had missing upper incisors in week 4 of treatment. No clinical signs were observed in females at 300 or 1000 mg/kg, while in males no clinical signs were oberved at 1000 mg/kg.

BODY WEIGHT AND WEIGHT GAIN
No test-item-related differences from the control group were recorded. Some significant differences were observed in group 3 but these were not considered of toxicological relevance.

FOOD CONSUMPTION
Food consumption was similar in all groups.

WATER CONSUMPTION
Slight increase in water consumption was recorded in females at 300 and 1000 mg/kg during pregnancy period. These differences were not statistically significant. In males no differences from the control group were recorded.

HAEMATOLOGY
No changes of toxicological relevance were recorded.

CLINICAL CHEMISTRY
No changes of toxicological relevance were recorded in females. Bilirubin, cholesterol and triglyceride values tended to be higher at 300 and 1000 mg/kg in females. An increase in bile acid values was observed at 300 mg/kg in males. The differences recorded were statistically significant with respect to the control group.

NEUROBEHAVIOUR
No differences in fore- or hind limb grip strength were recorded in males and females. Slightly lower locomotor activity was recorded in males at 100 mg/kg, being it statistically significant at 15 minutes. Slightly lower locomotor activity was recorded in females at 300 and 1000 mg/kg for 15-30 min, but the differences were not statistically significant. No differences were recorded in the remaining groups.

All animals responded positively to the different reflexes such as blink, pinna, righting and iridic reflexes and pain, auditory startle and handling response (push-off).

ORGAN WEIGHTS
At 1000 mg/kg, kidney weights tended to be slightly higher in males. These differences were not statistically significant. Moreover, lower pituitary and adrenal weights were recorded; the differences were statistically significant for pituitary in males. A trend to higher liver weight was recorded in females at 1000 mg/kg, but the differences were not statistically significant.
Concerning reproductive organs, lower left ovary weights were recorded at 1000 mg/kg. This difference was statistically significant in relation to body weight ratio.

GROSS PATHOLOGY
At 1000 mg/kg, large right kidney was observed in one male and reddish thymus in another one. A reddish area on cecum wall was observed in one male and reddish foci in lungs in another one. Likewise, thickened gastric mucosa was observed in one female and small spleen in another one.
At 300 mg/kg, reddish foci were observed in the thymus of one male. No findings were observed in females.
At 100 mg/kg, pale kidneys were observed in one male and reddish foci in lungs in another one. Likewise, left seminal vesicle reduced in size was observed in one male and reddish thymus in three males. Thickened gastric mucosa was observed in one female.
In the control group, one male had left seminal vesicle reduced in size. One male and one female had pale kidneys. In addition, one male had pancreas reduced in size and thymus with reddish foci.
Yellowish-whitish gastric mucosa was recorded in few females from all groups (including control group).

HISTOPATHOLOGY: NON-NEOPLASTIC
All microscopic findings recorded were considered to be within the range of normal background lesions that may be seen in rats of this strain and age and under the experimental conditions used in this study.

Key result

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: no adverse toxic effects observed

Key result

Critical effects observed:

no

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Quality of whole database:

The available information comprises an adequate and reliable study from a reference substance with similar structure and intrinsic properties. Read-across is justified based on common precursors and breakdown products of hydrolysis and consistent trends in environmental fate, ecotoxicological and toxicological profile (refer to the endpoint discussion for further details).
The selected study is thus sufficient to fulfil the standard information requirements set out in Annex VIII-IX, 8.6, in accordance with Annex XI, 1.5, of Regulation (EC) No 1907/2006.

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for read-across

There are no available data on the repeated dose toxicity of 2-octyldodecyl 12-[(1-oxooctadecyl)oxy]octadecanoate (CAS 90052-75-8). The assessment was therefore based on studies conducted with analogue substances as part of a read across approach, which is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. For each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across. A detailed justification for the analogue read-across approach is provided in the technical dossier (see IUCLID Section 13).

Repeated dose toxicity, oral, subacute

CAS 93803-87-3

A 28-day oral repeated dose toxicity study was performed according to OECD 407 and under GLP conditions, using octyldodecyl isooctadecanoate ( 1998, supporting study). 5 Wistar rats/sex/dose were administered 0, 50, 200 and 1000 mg/kg bw/day by gavage, for 28 consecutive days. There was no mortality and no toxicologically relevant clinical signs were observed during the study period. No significant differences in body weight, body weight gain and food consumption between the control group and treatment groups were noted. In females of the high-dose group, a statistically significant increase in relative leucocyte level (approximately 8%) and decrease in relative neutrophil level (app. 8%) was noted, compared with the control group values. These values are related to each other as a percentage of the total lymphocyte concentration, and a variation in one will necessarily affect one or several other specific lymphocyte values. As the changes are minimal, no effects were seen in males and no other haematological effects were noted, this result is considered not have toxicological relevance. In males of the high-dose group, the level of calcium and chloride was significantly increased. These increases were around 5% compared with the control group levels and no similar effects were observed in the female groups. Therefore, they are not considered to have toxicological relevance. No treatment-related effects on neurobehavioural parameters were observed. There were no significant differences in absolute or relative organ weight in the treatment groups, compared to the control group. The macroscopic inspection at autopsy and subsequent histopathological examination did not reveal any treatment-related changes. Based on the lack of toxicologically relevant effects up to and including the highest dose level, the NOAEL is considered to be ≥ 1000 mg/kg bw/day.

CAS 17671-27-1

In a combined repeated dose toxicity and reproduction/developmental toxicity screening study performed according to OECD guideline 422 under GLP conditions, the potential adverse effects of Docosyl docosanoate were assessed (key, 2014). 10 rats/dose/day were administered 0, 100, 300 and 1000 mg/kg bw/day Docosyl docosanoate once daily via gavage up to day 49 of treatment (males) or day 4 postpartum (females). The application started two weeks before mating on test day one and ended one day before sacrifice. No test item-related premature death was noted. No test item-related signs of toxicity were noted during the observational and neurological screenings. A treatment-related decrease in body weight was noted for the female animals of the high dose group (1000 mg /kg bw/day) on lactation day 4. No toxicologically relevant effects were observed on the haematological and clinical chemistry parameters. The macroscopic inspection at autopsy and subsequent histopathological examination did not show any treatment-related changes. The NOAEL for systemic toxicity was determined to be ≥ 1000 mg/kg bw/day in this study.

CAS 22393-85-7

A combined repeated dose toxicity and reproduction/developmental toxicity screening study was performed according to OECD guideline 422 and in compliance with GLP (supporting, 2014). 10 rats/sex/dose were administered 0, 100, 300 and 1000 mg/kg bw/day Tetradecyl oleate once daily for 28-29 days (males) and up to 54 days (females) via gavage. The application started two weeks before mating on test day one and ended on the day of or one day before sacrifice. Day of sacrifice was on test day 29 or 30 for the male rats and on lactation day 3 or shortly thereafter for the female rats. There was no mortality during the study period. No toxicologically relevant clinical signs were observed. The body weight, body weight gain and food consumption was comparable between the control and treatment groups. There were no toxicologically relevant effects on organ weights. The statistically significant differences in haematological parameters between control and treated animals (erythrocytes, mean corpuscular haemoglobin and leucocytes in males, haemoglobin, haematocrit and platelets in females) were of low magnitude and/or not dose-related, and therefore considered incidental. Statistically significant fluctuations of some biochemical parameters, compared with the control groups, were recorded in both sexes. An increase in glucose levels in males administered 100 and 1000 mg/kg bw/day (48% for both doses), and an increase in urea in males receiving 100 mg/kg bw/day (19%) was observed. In females in the 300 mg/kg bw/day group, an increase in aspartate aminotransferase level (35%) was noted, while for females administered 1000 mg/kg bw/day, a decrease in bilirubin levels (81%) and an increase in potassium levels (10%) were observed. Due to the lack of dose- and/or sex-consistency, and due to the absence of other relevant findings, these changes are not considered to be toxicologically relevant. There was no significant difference between control and treatment groups during the observational and neurological screenings. The macroscopic inspection at autopsy and subsequent histopathological examination did not show any treatment-related changes. The NOAEL for systemic toxicity was considered to be ≥ 1000 mg/kg bw/day.

 

Overall conclusion for repeated dose toxicity

Analogue read-across from subacute studies from 3 source substances was applied to assess the potential for the target substance to causerepeated dose toxicity. The NOAEL values for repeated dose toxicity were at or above the currently applied limit dose value of 1000 mg/kg bw/day. No hazard after repeated oral exposure was identified. Therefore, 2-octyldodecyl 12-[(1-oxooctadecyl)oxy]octadecanoate is not expected to cause long-term toxic effects via the oral route.

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Since the analogue concept is applied to 2-octyldodecyl 12-[(1-oxooctadecyl)oxy]octadecanoate, data will be generated from data for reference source substance(s) to avoid unnecessary animal testing. Additionally, once the analogue read-across concept is applied, substances will be classified and labelled on this basis.

Therefore, based on the analogue read-across approach, the available data on repeated dose toxicity do not meet the classification criteria according to Regulation (EC) 1272/2008, and are therefore conclusive but not sufficient for classification.