O,O'-dioctadecylpentaerythritol bis(phosphite)

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

31 December 2005 to 6 March 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, done to a valid guideline and the study was conducted under GLP conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3550 (Reproduction/ Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

O,O'-dioctadecylpentaerythritol bis(phosphite)

EC Number:

223-276-6

EC Name:

O,O'-dioctadecylpentaerythritol bis(phosphite)

Cas Number:

3806-34-6

Molecular formula:

C41H82O6P2

IUPAC Name:

3,9-bis(octadecyloxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Weston 618G
- Physical state: solid
- Storage condition of test material: refrigeration (2 - 8 °C)

Test animals

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Advinus Therapeutics Private Ltd., Bangalore - 560 058, India
- Age at study initiation: 12 weeks
- Weight at study initiation:
Males: Control 375 ± 17.1 g, 100 mg/kg 378 ± 16.2 g, 400 mg/kg 378 ± 18.9 g and 1000 mg/kg 377 ± 13.9 g (mean ± SD)
Females: Control 235 ± 10.4 g, 100 mg/kg 234 ± 13.7 g, 400 mg/kg 233 ± 11.9 g and 1000 mg/kg 233 ± 9.9 g (mean ± SD)
- Housing: groups of 2 per sex in sterilised suspended standard polyproylene cages (males); individually in polypropylene cages with steam sterilised paddy husk and sterilised nesting material from gestation day 20 up to lactation day 4 (females)
- Diet: Ssniff rats/mice food (Sniff Spezialdiäten GmbH., Ferdinand-Gabriel-Weg 16, D-59494 Söest, Germany) ad libitum
- Water: purified deep bore-well water
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 23 ºC
- Humidity (%): 30 - 70 %
- Air changes (per hr): 12 - 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12 hours light / 12 hours dark

IN-LIFE DATES: From 31 December 1995 to 6 March 2006

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

CMC (carboxymethyl cellulose)

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: test material suspensions in CMC were prepared daily before gavage administration. Test material was ground in a pestle and mortar before being added to 0.5% aqueous carboxymethyl cellulose. The suspension was made up to the final volume of 90 mL to get test material concentrations of 10, 40 and 100 mg/mL.Test material was administered at an equivolume of 10 mL/kg bw.

VEHICLE
- Justification for use and choice of vehicle (if other than water): based on a solubility test, the test material was found to be insoluble in water but a clear suspension was formed in aqueous 0.5% carboxymethyl cellulose.

Analytical verification of doses or concentrations:

no

Details on mating procedure:

- M/F ratio per cage: 1 male / 1 female
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 of pregnancy

Duration of treatment / exposure:

- Once daily for 2 weeks, continuing during mating period and approximately 2 weeks post mating (males)
- Once daily throughout treatment period. Treatment started 2 weeks prior to the mating period and continued through mating, pregnancy and up to lactation day 4 (females)

Frequency of treatment:

Daily

Duration of test:

The males were dosed for a minimum period of 4 weeks, up to and including the day before scheduled sacrifice (this included a minimum of 2 weeks prior to mating, during the mating period and approximately 2 weeks post mating). Females were dosed throughout the treatment period. This included 2 weeks prior to mating (with the objective of covering at least 2 complete oestrous cycles), the variable time to conception, the duration of pregnancy and at least 4 days after delivery, up to and including the day before scheduled sacrifice.

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 100, 400, 1000 mg/kg
Basis:
nominal conc.

No. of animals per sex per dose:

10 males and 10 females per dose level

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: dose levels selected in consideration of results from a 7-day oral (gavage) toxicity study with 2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5]undecane, 3,9-bis(octadecyloxy)-(9Cl) in Wistar rats treated at 100, 400 and 1000 mg/kg bw/day. Under the conditions of the study no clinical signs were observed, there were no deaths and body weights, food intake, organ weights and gross pathology did not reveal any significant differences in treatment groups compared to the respective controls.
- Rationale for animal assignment (if not random): Grouping was done one day before treatment using an in-house method of bodyweight stratification and distribution. The rats procured for the study were weighed and segregated depending on bodyweight ragnes. The bodyweight randes were 331-410 for males and 201-270 g for females. Animals with bodyweight ranges 341-350, 351-360, 361-370, 371-380, 381-390 and 391-400 g for males and 211-220, 221-230, 231-240, 241-250 and 251-260 g for females were selected and rats within each bodyweight range were randomly distributed to all groups to attain groups whose mean bodyweight variation were not more than 20 %.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily
- Cage side observations: checks for morbidity and mortality

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: daily
- Cage side observations: appearance, behaviour and clinical signs including signs of difficult and prolonged parturition.

BODY WEIGHT: Yes
- Time schedule for examinations: day 1 of treatment and at least weekly thereafter. All dams were weighed on gestation days 0, 7, 14 and 20 and on lactation days 0 and 4.

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

WATER CONSUMPTION: No

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes. Detailed histological examination was performed on the ovaries.
Examinations included:
- Gravid uterus weight: No data
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No data
- Number of late resorptions: No data

Fetal examinations:

- External examinations: Yes: [all per litter]
- Soft tissue examinations: No data
- Skeletal examinations: No data
- Head examinations: No data

Statistics:

The significance of group differences was tested using Dunnett's 't' test and the Student's 't' test.

Indices:

Mean no. of corpora lutea = total no. of corpora lutea / no. of dams used for corpora lutea count

Mean no. of implantations = total no. of implantation / no. of dams used for implantation count

Implantations = (total no. of implantations / total no. of corpora lutea) x 100

Pre-implantation loss = (no. of corpora lutea – no. of implantations / no. of corpora lutea) x 100

Post implantation loss = (no. of implantations – no. of live pups / no. of implantations) x 100

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
CLINICAL SIGNS AND MORTALITY
There were no pre-terminal deaths at any of the doses tested and no clinical signs were observed. The partial cannibalism of pups was observed in three females in control and three females of the high dose group and all pups cannibalism was observed in one female of the mid dose group.

BODY WEIGHT AND FOOD CONSUMPTION
Body weights and food consumption were unaffected by treatment with the test material at all dose levels.

REPRODUCTIVE PERFORMANCE
Percentage of implantations, parturition percentage, percentage of pre-implantation loss, post-implantation loss and live pups born were unaffected by the treatment at all doses tested when compared to control. The significantly higher percentage of pre-implantation loss resulted in lower percentage of implantations at the low and mid doses. These findings were considered incidental as there were no changes observed at the high dose.

GROSS PATHOLOGY
There were no treatment related gross changes in females. The few incidences of lesions observed were randomly distributed among the various groups and were hence considered incidental.

HISTOPATHOLOGY
No lesions were observed in the ovaries in the control and high dose animals examined for histopathology.

Effect levels (maternal animals)

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
GROSS PATHOLOGY
There was a single incidence of a rudimentary tail in one high dose male pup. This was considered an incidental change and thus there were no treatment related gross changes observed in the pups.

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

Under the conditions of the study, the No Observed Effect Level for maternal toxicity and developmental toxicity was determined to be 1000 mg/kg bw when dosed to Wistar rats via oral gavage.

Executive summary:

The reproductive and developmental toxicity of the test material was investigated in accordance with standardised guidelines OECD 421 and EPA OPPTS 870.3550. During the study rats were dosed test material by gavage, at daily concentrations of 0 (vehicle control), 100, 400 and 1000 mg/kg bw. Following two weeks of treatment, animals were mated and treatment continued for another two weeks (minimum). Animals were observed for mortality and clinical signs during the treatment period; body weights and food consumption were also recorded. At the end of the treatment period animals were sacrificed and subjected to gross and histopathological examination. Under the conditions of the study, it was concluded that the oral administration of the test material to rats at the concentration of 1000 mg/kg, had no effects on general health, body weights and food consumption. There were no treatment-related signs and no pre-terminal deaths. No treatment-related effects were observed on gestation and lactation body weights and food consumption, number and weight of pups, viability of pups, fertility indices of parental animals, terminal body weights, organ weights and their ratios in males. There were also no treatment-related gross and histopathological changes. In consideration of the findings, the No Observed Effect Level was determined to be 1000 mg/kg bw.