Branched and linear octadecanoic acid, esters with glycerol oligomers

Endpoint summary

Description of key information

- oral (diet): 28-day study in rats: NOAEL(male rats) = 845 mg/kg bw/day; NOAEL (female rats) = 922 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

Type of information:

read-across from similar mixture/product

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Study was not performed under GLP

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Version / remarks:

16 Oct 2008

Deviations:

no

Principles of method if other than guideline:

Male and female Sprague-Dawley rats were administered 0.012, 0.12 and 1.2% of the test substance in diet for 28 days. Parameters evaluated were: mortality, clinical signs, body weight and body weight gains, food consumption, food efficiency and dietary intake, gross necropsy, organ weights, organ to body and brain weight ratios, clinical examinations, histopathology.

GLP compliance:

no

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Details on species / strain selection:

CrlCD (SD) IGS BR rat was selected for use as the test system because this strain of rat has been widely accepted for dietary toxicity tests.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories (Raleigh, North Carolina, USA)
- Age at study initiation: 9 weeks
- Weight at study initiation: 208 - 315 g (males) and 207 - 244 g (females)
- Fasting period before study: no
- Housing: Individually housed in suspended stainless steel caging with mesh floors. Litter paper was placed beneath the cage and was changed at least three times per week.
- Diet: Purina Certified Rodent Meal #5002 (PMI Nutrition International), ad libitum
- Water: Filtered tap water, ad libitum
- Acclimation period: 12 days

DETAILS OF FOOD AND WATER QUALITY: The results for possible contaminants were acceptable within regulatory standards.
- Animal feed was analyzed for the presence of the following contaminants by PMI Nutrition International: Aldrin, BHC-A, BHC-B, BHC-D, BHC-G, Heptachlor Epoxide, DDE, DDT, Aflatoxin, Ethion, Methyl Parathion, Thimet, Trithion, Chlordane, Endrin, Heptachlor, Methoxychlor, Mirex, Diazinon, Hexachlorobenzene, PCB, Disulfoton, Malathion, Parathion, Thiondan, Dieldrin.
- Water was analyzed for NJDEPE Safe Drinking Water Act parameters by New Jersey Laboratories I.D. and by Silliker Laboratories of New Jersey, INC..

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 - 26
- Humidity (%): 35 - 70
- Photoperiod (hrs dark / hrs light): 12 / 12

Route of administration:

oral: feed

Details on route of administration:

No data

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

DIET PREPARATION
- Rate of preparation of diet: Diets were prepared three times during the study (Pre-Test; Test Days 3 and 13) in a sequential order starting with the control, then from the lowest concentration (0.012%) to the highest concentration (1.2%).
- Mixing appropriate amounts with (Type of food): The test substance for each 3.0 kg diet was accurately weighed using a tared syringe (B-D Luer-Lok plastic syringe) and a calibrated electronic balance (AND, Model FY300). Homogeneous distribution of the test substance for each concentration of diet (except for control) was optimized by the preparation of a premix (the aliquot of test substance and a variable portion of rat chow to achieve a semi-dry appearance) in a tabletop blender (Osterizer, 12-speed); the premix was then added to the remaining rat chow and mixed in a high 3-speed mixer (Hobart, Model A200). Each diet was transferred from the mixing bowl to a polypropylene bag identified with study number, concentration and date of preparation, prior to refrigeration (approximately 5 °C).
- Storage temperature of food: under refrigeration

Analytical verification of doses or concentrations:

no

Duration of treatment / exposure:

28 days

Frequency of treatment:

Continuous with diet

Dose / conc.:

0.012 other: %

Remarks:

(corresponds to 9 mg/kg bw/day for male rats and 10 mg/kg bw/day for female rats)

Dose / conc.:

0.12 other: %

Remarks:

(corresponds to 91 mg/kg bw/day for male rats and 100 mg/kg bw/day for female rats)

Dose / conc.:

1.2 other: %

Remarks:

(corresponds to 845 mg/kg bw/day for male rats and 922 mg/kg bw/day for female rats)

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Dose selection rationale: The human exposure to the test substance is expected to be approximately 0.7 mg/kg bw/day. The levels selected for this study are at least 10x, 100x and 1000x the expected human exposure.

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: weekly

BODY WEIGHT: Yes
- Time schedule: twice during acclimation period, prior to study initiation (Day 0) and weekly thereafter.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
Individual food consumption was measured and recorded weekly. The average daily dietary intake of the test substance was calculated.

FOOD EFFICIENCY: Yes
Food efficiency was calculated by dividing the body weight gain by the food consumption over equivalent periods.

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Parameters checked: hemoglobin concentration (HGB), mean corpuscular volume (MCV), erythrocyte count (RBC), total white blood cell (WBC) and differential leukocyte count, platelet count (PLT), red cell distribution width (RDW), prothrombin time (PT) and activated partial thromboplastin time (APTT), absolute reticulocyte count (ARET), hematocrit (HCT), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC)

CLINICAL CHEMISTRY: Yes
- Parameters checked: calcium (CALC), inorganic phosphorus (IPHS), chloride (CL), sodium (NA), potassium (K), fasting glucose (GLUC), serum alanine aminotransferase (ALT), serum aspartate aminotransferase (AST), sorbital dehydrogenase (SDH), alkaline phosphatase (ALKP), urea nitrogen (BUN), albumin (ALB), blood creatinine (CREA), total bilirubin (BILI), total serum protein (TP), globulin (GLOB), total cholesterol (CHOL) and trigylcerides (TRIG)

URINALYSIS: No

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
- Examinations: External surface of the body, all orifices and the thoracic, abdominal and cranial cavities and their contents. Wet organ weights of liver, kidneys, adrenals, brain, heart, thymus, spleen, testes and epididymides

HISTOPATHOLOGY: Yes (only control and high-dose group)
- Histopathological examination: Lungs, brain-including sections of medulla/pons, cerebellar cortex and cerebral cortex, spinal cord (cervical, mid-thoraic, lumbar), pituitary, thyroid, thymus, trachea, heart, sternum with bone marrow, liver, spleen, kidneys, adrenals, pancreas, ovaries, testes, uterus, vagina, accessory genital organs (epididymides, prostate, seminal vesicles), stomach, duodenum, jejunum, ileum, cecum, colon, rectum, urinary bladder, representative lymph node and peripheral nerve (sciatic)

Statistics:

- Mean and standard deviations were calculated for body weight, body weight gain, food consumption, food efficiency, organ weight and organ to body/brain weight ratio data. Treated and control groups were compared using a One-Way of Analysis (ANOVA), followed by comparison of the treated groups to control by Dunnett`s Multiple Comparisons test. Data was evaluated for homogeneity of variances and normality by the Bartlett`s test and Kolmogrov and Smimov test, respectively. Data that was considered significant by Bartlett`s test was further run with a non-parametric method (Dunn`s test). (INSTAT Biostatistics, Graph Pad Software, San Diego, CA, USA) Significance was judged at p < 0.05. Male and female rats were evaluated separately.

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Statistical difference between high dose females and control group in weekly body weight gain was noted during week 1, there were no other statistically significant differences (p > 0.05) in body weight or body weight gains between any test and their corresponding control groups.

Food consumption and compound intake (if feeding study):

effects observed, non-treatment-related

Description (incidence and severity):

Statistical differences between high dose females and control group in weekly food consumption were noted during week 1, there were no other statistically significant differences (p > 0.05) in food consumption between any test and their corresponding control groups.

Food efficiency:

effects observed, non-treatment-related

Description (incidence and severity):

Statistical differences between high dose females and control group in food efficiency were noted during week 1, there were no other statistically significant differences (p > 0.05) in food efficiency between any test and their corresponding control groups.

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Statistically significant increases in liver to body weight and kidney to body/brain weight ratios in high dose male rats compared to control values. Significant weight increases were also observed in high dose female rats for absolute liver and organ to body weight/brain weight ratios.

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Gross necropsy findings at terminal sacrifice revealed dark discolored fluid in the colon of one male rat of the high dose test group.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Other effects:

not examined

Details on results:

- Mortality:
There were no mortalities during this study.
- Clinical observations:
All animals appeared active and healthy. There were no signs of gross toxicity, adverse pharmacologic effects or abnormal behavior.
- Body weight and body weight gain:
Statistical difference between high dose females and control group in weekly body weight gain was noted during week 1, there were no other statistically significant differences (p > 0.05) in body weight or body weight gains between any test and their corresponding control groups. Thus, body weight was considered not affected by the dietary administration of the test substance.
- Food consumption, food efficiency and dietary intake:
Statistical differences between high dose females and control group in weekly food consumption and food efficiency were noted during week 1, there were no other statistically significant differences (p > 0.05) in food consumption and efficiency between any test and their corresponding control groups. Thus, no adverse effects in these parameters were produced by the dietary administration of the test substance. The average daily intake in male rats fed dietary concentrations of approximately 0.012%, 0.12% and 1.2% was 9, 91 and 845 mg/kg/day, respectively. For the same dietary concentrations, the average daily intake in female rats was 10, 100 and 922 mg/kg/day, respectively. Since no analyses of diets were performed, these values are based on nominal concentrations in diets.
- Gross necropsy:
Gross necropsy findings at terminal sacrifice revealed dark discolored fluid in the colon of one male rat of the high dose test group. This finding was isolated and considered not related to dietary administration of the test substance. All other findings at terminal sacrifice were unremarkable.
- Organ weights, organ to body and brain weight ratios:
Statistically significant increases in liver to body weight and kidney to body/brain weight ratios in high dose male rats compared to control values. Significant weight increases were also observed in high dose female rats for absolute liver and organ to body weight/brain weight ratios. Given the absence of histological alterations in livers and kidneys, and the absence of changes in clinical pathology indicators of renal and hepatic function, these organ weight increases in high dose male and/or female rats were judged not to be of clinical significance. The liver weight increases are likely indicative of a normal physiological compensatory response to a high level oral exposure (i.e., significantly exceeds the expected human exposure) of a xenobiotic.
- Clinical examinations:
There were no adverse or treatment-related changes in hematology, coagulation, or clinical chemistry parameters in male or female rats.
- Histopathology:
There were no treatment-related macroscopic changes present in this study. There was no histologic correlation to the increases in liver weight noted in treated rats. All other microscopic lesions were of the type and incidence commonly noted in Sprague-Dawley rats.

Key result

Dose descriptor:

NOAEL

Effect level:

845 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male

Remarks on result:

other: corresponds to 1.2%

Key result

Dose descriptor:

NOAEL

Effect level:

922 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

female

Remarks on result:

other: corresponds to 1.2%

Key result

Critical effects observed:

no

Table 1 Average Weekly Body Weight (g)

Dose level (mg/kg bw/day)		0	10	100	1000
Number of animals		5	5	5	5
Week	MALES
Initial	Average	296.0	298.8	296.0	298.2
	SD	8.5	10.8	10.5	8.8
1	Average	334.2	340.6	330.2	336.2
	SD	12.9	15.0	28.0	12.5
2	Average	374.2	381.6	368.0	372.4
	SD	19.7	22.5	40.6	14.9
3	Average	407.2	419.4	401.0	402.2
	SD	19.6	16.0	47.1	13.8
4	Average	429.0	441.2	415.6	421.2
	SD	23.7	19.8	50.9	17.0
	FEMALES
Initial	Average	222.8	224.8	220.6	221.2
	SD	13.2	10.7	11.7	9.7
1	Average	237.2	238.8	231.2	220.4
	SD	16.2	11.6	14.8	12.2
2	Average	253.0	255.4	252.8	235.2
	SD	20.4	15.2	19.8	12.5
3	Average	267.6	272.0	260.0	248.6
	SD	27.6	16.0	17.2	12.5
4	Average	278.0	279.6	275.2	255.8
	SD	29.1	17.6	18.8	15.3

Table 2: Average Body Weight Gain (g)

Dose level (mg/kg bw/day)		0	10	100	1000
Number of animals		5	5	5	5
Week	MALES
Initial	Average	38.2	41.8	34.2	38.0
	SD	5.8	9.3	21.3	8.6
1	Average	40.0	41.0	37.8	36.2
	SD	7.3	8.6	13.1	4.0
2	Average	33.0	37.8	33.0	29.8
	SD	6.3	8.9	7.2	6.2
3	Average	21.8	21.8	14.6	19.0
	SD	8.8	6.9	14.9	8.6
4	Average	33.3	35.6	29.9	30.8
	SD	3.9	3.3	11.5	3.9
	FEMALES
Initial	Average	14.4	14.0	10.6	-0.8*
	SD	5.7	10.0	4.4	8.5
1	Average	15.8	16.6	21.6	14.8
	SD	6.2	5.8	7.3	2.7
2	Average	14.6	16.6	7.2	13.4
	SD	10.1	3.7	5.2	3.6
3	Average	10.4	7.6	15.2	7.2
	SD	7.8	2.9	3.0	4.3
4	Average	13.8	13.7	13.7	8.7
	SD	4.5	3.5	2.0	2.2

* Statistically significantly decreased (p < 0.01) compared to control group

Table 3: Organ Weights and Ratios in Females (g)

Dose level (mg/kg bw/day)		0	10	100	1000
Number of organs		5	5	5	5
Organ	Average Organ Weights (g)
Liver	Average	7.2	8.0	7.7	8.7*
	SD	0.7	0.8	0.7	0.4
Organ	Average Organ to Body Weight Ratios (g)
Liver	Average	28.1	30.7	30.0	36.6*
	SD	3.30	2.98	1.24	1.49
Organ	Average Organ to Brain Weight Ratios (g)
Liver	Average	3.80	4.23	4.30	5.40*
	SD	0.57	0.31	0.36	1.28

* Statistically significantly decreased (p < 0.01) compared to control group

Table 4: Organ Weights and Ratios in Males (g)

Dose level (mg/kg bw/day)		0	10	100	1000
Number of organs		5	5	5	5
Organ	Average Organ Weights (g)
Liver	Average	10.8	12.6	11.3	12.6
	SD	1.4	1.9	2.4	0.9
Kidneys (paired)	Average	2.9	3.4	3.1	3.4
	SD	0.3	0.3	0.4	0.2
Organ	Average Organ to Body Weight Ratios (g)
Liver	Average	27.0	30.4	29.0	31.8*
	SD	2.26	3.81	2.43	1.14
Kidneys (paired)	Average	7.33	8.17	7.89	8.61*
	SD	0.50	0.61	0.62	0.70
Organ	Average Organ to Brain Weight Ratios (g)
Liver	Average	5.26	6.06	5.49	6.36
	SD	0.85	1.28	1.07	0.52
Kidneys (paired)	Average	1.42	1.62	1.48	1.72*
	SD	0.10	0.06	0.04	0.04

* Statistically significantly decreased (p < 0.01) compared to control group

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

845 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The available information comprises an adequate and reliable (RL2) key study with a read-across substance. However, LoA negotiations are still ongoing and currently only a short summary was provided by the study owner. Therefore, the available data is not yet sufficient to fulfil the standard information requirements set out in Annex VIII, 8.6, 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

Repeated dose toxicity

Justification for read-across

There are no data available regarding repeated dose toxicity for Polyaldo 2-1-IS (CAS 73296-86-3). Read-across from an appropriate substance is conducted in accordance with Regulation (EC) No 1907/2006, Annex XI, 1.5. in order to fulfil the standard data requirements defined in Regulation (EC) No 1907/2006, Annex VIII, 8.6. 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).

As no data on repeated dose toxicity is available for Polyaldo 2-1-IS (CAS 73296-86-3) information will be taken into account from the analogue substance Di(isooctadecanoic) acid, diester with oxydi(propanediol) (CAS 67938-21-0) to fulfill the standard data requirements defined in Regulation (EC) No 1907/2006, Annex VIII, 8.6.

CAS 67938-21-0

There is an oral 28-day dietary repeated dose toxicity study in rats with the analogue substance Di(isooctadecanoic) acid, diester with oxydi(propanediol) (CAS 67938-21-0) available. Male and female Sprague-Dawley rats were administered 0.012, 0.12 and 1.2% of the test substance in diet (corresponding to 9, 91 and 845 mg/kg bw/day for male rats and 10, 100 and 922 mg/kg bw/day for female rats) for 28 days. No mortality and clinical signs or effects on body weight or body weight gains were observed during treatment. No adverse effects in food consumption, food efficiency and dietary intake were seen. Gross necropsy revealed no abnormalities. There were statistically significant increases in liver to body weight and kidney to body/brain weight ratios in high dose male rats compared to control values. Significant weight increases were also observed in high dose female rats for absolute liver and organ to body weight/brain weight ratios. No adverse or treatment-related changes in hematology, coagulation, or clinical chemistry parameters in male or female rats and no treatment-related macroscopic changes were present in the study. Given the absence of histological alterations in livers and kidneys, and the absence of changes in clinical pathology indicators of renal and hepatic function, the observed organ weight increases in high dose male and/or female rats were judged not to be of clinical significance. Under the conditions of this study and based on the toxicological endpoints evaluated, the NOAEL was considered to be 845 mg/kg bw/day for male rats and 922 mg/kg bw/day for female rats.

Justification for classification or non-classification

The available data of the appropriate read-across substance Di(isooctadecanoic) acid, diester with oxydi(propanediol) (CAS 67938-21-0) do not meet the criteria for classification according to Regulation (EC) No 1272/2008, and are therefore conclusive but not sufficient for classification.