3,9-bis[2,4-bis(1-methyl-1-phenylethyl)phenoxy]-2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane;bis(2,4-dicumylphenyl) neopentyl diphosphite

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

421-920-2

EC Name:

-

Cas Number:

154862-43-8

Molecular formula:

C53-H58-O6-P2

IUPAC Name:

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

Specific details on test material used for the study:

TEST ITEM NAME: Doverphos S-9228PC
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: Dover Chemical Corporation, Lot No. 46D030816
- Expiration date of the lot/batch: March 08, 2017
- Purity: 99.3%
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: In original container in a dry/cool, well ventilated place.
- Solubility and stability of the test substance in the solvent/vehicle: stable in vehicle for 4 hours.

Test animals

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Animal Breeding Facility, Jai Research Foundation
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 11 to 13 wks
- Housing: individually, except during the mating period. During the mating period, the rats were housed in groups of 2 rats/cage (one male plus one female). Confirmed mated female rats were caged individually, and nesting material was provided from 14th day of gestation. During the study, the rats were housed in solid floor polypropylene rat cages (size: 41 x 28.2 x 18 cm). Each cage was fitted with a stainless steel top grill having provision for keeping a polypropylene water bottle with stainless steel drinking nozzle. The bottom of the cages were layered with clean sterilized rice (paddy) husk as the bedding.
- Diet (e.g. ad libitum): standard rodent pellet feed (Teklad Certified Global 16% Protein Rodent diet manufactured by Envigo, USA) ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 6 days ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 - 24 deg C
- Humidity (%): 64 - 67%
- Air changes (per hr): 20-21
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: The test dose formulations were prepared every day prior to dosing and were used within 4 hours of preparation. The prepared formulation was kept on
a magnetic stirrer in order to maintain a homogeneous preparation. The dose volume was 10 mL/kg body weight.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The concentration and homogeneity of the test item in the dose formulation was analysed using a vali dated HPLC method once before initiation of treatment and twice during treatment period. Dose form ulations were found to be within the acceptance level of ± 15% of nominal concentration demonstrati ng that the prepared concentrations were as intended by the study plan and %CV was less than 10, suggesting that the prepared formulations were homogeneously mixed.

Details on mating procedure:

Each female was placed with a single male from the same dose level until copulation occurred or 2 weeks had elapsed. Each morning, the females were examined for the presence of sperm and the ‘day 0’ of pregnancy was recorded. Day 0 of pregnancy was defined as the day on which sperm was observed in the vaginal smears of rats.

Duration of treatment / exposure:

Dosing of both the sexes was initiated 2 weeks prior to mating and continued during the mating period. After mating, the male rats were further dosed up to and including the day before scheduled sacrifice (after approximately 80% of the females had delivered ). Females were further dosed during pregnancy and up to post-partum day 3.

Frequency of treatment:

once daily, seven days a week, at approximately the same time each day

Duration of test:

See Duration of treatment / exposure above

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

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

Doses / concentrations 2

Dose / conc.:

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

Doses / concentrations 3

Dose / conc.:

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

Doses / concentrations 4

Dose / conc.:

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

No. of animals per sex per dose:

15 males and 15 females per group

Control animals:

yes, concurrent vehicle

Details on study design:

The dose levels were selected based on the results of 14-day dose range finding study (JRF Study N° 410-1-04-14642), in which no test item related effect was observed in high dose (i.e., 1000 mg/kg b. wt./day) on body weight, feed consumption and organ weight.

Examinations

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Animals were observed twice a day for mortality and morbidity
DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: All animals were observed twice a day for visible clinical signs during the treatment period.
BODY WEIGHT: Yes
- Time schedule for examinations: Body weight of all the male animals were recorded on the first d ay of dosing and at weekly interval thereafter and at death. Body weight of all female animals was recorded on first day of dosing and at weekly interval during pre-mating and mating period. During gestation period, female animals were weighed on gestation days 0, 7, 14 and 20. During lactation p eriod, female animals were weighed within 24 hours of parturition (day 0 post-partum), post-partum day 4 (i.e., lactation day 4) and at death.
FOOD CONSUMPTION:
- Feed consumption of all male animals was measured weekly during pre-mating and post-mating p eriod. For female animals, during pre-mating period feed weights were recorded at weekly interval. During gestation period, feed weights were measured on days 0, 7, 14 and 20 and during lactation period, feed weights were measured on lactation days 0 and 4. Feed consumption was not measured during mating period.
GROSS PATHOLOGY
- All animals were subjected to full gross necropsy.

Ovaries and uterine content:

During sacrifice, number of corpora lutea and implantation sites were recorded for each dam.

Fetal examinations:

Each litter was examined as soon as possible after delivery to establish the number of pups, sex of pups, stillbirths, runts and the presence of gross anomalies. Pups which were found dead in the study were weighed and subjected to post-mortem examination.

Individual pup body weight was recorded on lactation days 0 and 4.

All pups were subjected to gross pathological examination.

Statistics:

Data such as body weight, body weight change, feed consumption, uterine data (number of imp lantation, number of corpora lutea, the mean number and percent of pre-implantation, post-implantat ion and post-natal loss), litter parameters (number and weight of male pups, female pups, total pup
s (male + female)), duration of gestation and pre-coital interval were analysed using Bartlett’s test
of homogeneity of variance. If the result was not significant then analysis of variance (ANOVA) was carried out and if the results was significant then t-test was carried out. If ANOVA was significant then Dunnett’s multiple comparison tests was carried out.
Data such as mortality rate, gestation index, parturition index, pups survival index, live birth index and fertility index were analyzed using Chi-Square test.

Indices:

Reproductive indices
male fertility index, female fertility index, gestation index, parturition index and mating index, gestation period and pre-coital interval, pre-implantation loss, pre-natal (post-implantation) loss, post-natal loss.

Offspring viability indices
live pups index and live birth index, survival / mortality index

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:

no effects observed

Mortality:

mortality observed, non-treatment-related

Body weight and weight changes:

no effects observed

Gross pathological findings:

no effects observed

Maternal developmental toxicity

Details on maternal toxic effects:

no effects were observed on duration of pregnancy, pre-implantation loss, parturition index, or live birth index.

Effect levels (maternal animals)

Key result

Dose descriptor:

NOAEL

Effect level:

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

Basis for effect level:

other: No effects observed at the limit dose of 1000 mg/kg/day

Maternal abnormalities

Key result

Abnormalities:

no effects observed

Results (fetuses)

Fetal body weight changes:

no effects observed

Description (incidence and severity):

Migrated Data from removed field(s)
Field "Fetal/pup body weight changes" (Path: ENDPOINT_STUDY_RECORD.DevelopmentalToxicityTeratogenicity.ResultsAndDiscussion.ResultsFetuses.FetalPupBodyWeightChanges): no effects observed

Reduction in number of live offspring:

no effects observed

Changes in sex ratio:

no effects observed

Changes in litter size and weights:

no effects observed

Changes in postnatal survival:

no effects observed

External malformations:

no effects observed

Effect levels (fetuses)

Key result

Dose descriptor:

NOAEL

Effect level:

>= 1 000 other: maternal dose in mg/kg bw/day (actual dose received)

Sex:

male/female

Basis for effect level:

other: No effects observed at the highest dose tested

Overall developmental toxicity

Developmental effects observed:

no

Applicant's summary and conclusion

Conclusions:

Daily oral gavage administration of the Doverphos S9228PC to male and female rats at dose levels of 250, 500 and 1000 mg/kg b. wt./day during pre-mating, mating, post-mating, gestation period and until post-partum day 3 did not produce test item-related adverse effects on reproduction and development. Thus, the No Observed Adverse Effect Level of Doverphos S9228PC was found to be 1000 mg/kg b. wt./day.