Registration Dossier

Administrative data

Endpoint:
toxicity to reproduction: other studies
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Modern GLP study conducted in accordance with modern guidelines.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: OECD Test Guideline 421
Deviations:
no
GLP compliance:
yes
Type of method:
in vivo

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Physical state: Solid.
- Analytical purity: >99%.
- Lot/batch No.: E0011-039E
- Expiration date of the lot/batch: 30 October 2012
- Storage condition of test material: Room temperature, protected from light

Test animals

Species:
rat
Strain:
other: Crl:CD(SD)
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Inc., Raleigh, NC, USA.
- Age at study initiation: (P) 10.5 wks.
- Weight at study initiation: (P) Males: 344-387 g; Females: 210-260 g.
- Fasting period before study: None.
- Housing: Animals were housed individually in clean, stainless steel wire-mesh cages suspended above cage board. Following mating, or the end of the mating period, females were transferred to plastic maternity cages with nesting material, ground corncob bedding.
- Diet (e.g. ad libitum): Ad libitum.
- Water (e.g. ad libitum): Ad libitum.
- Acclimation period: 10 days.


ENVIRONMENTAL CONDITIONS
- Temperature (°C): Set to maintain 19-25 deg C. Actual mean daily temperature ranged from 21.4-22 deg C during the study.
- Humidity (%): Set to maintain 20–70%. Actual mean daily relative humidity ranged from 42.8-60.1% during the study.
- Air changes (per hr): At least 10.
- Photoperiod (hrs dark / hrs light): 12/12 (06:00-18:00).


IN-LIFE DATES: From: 06 May 2008 To: 07 July 2008.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
corn oil
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: Test substance formulations were prepared approximately weekly as single formulations for each dosage levell and stirred continuously at room temperature, protected from light. The volume required for dosing was dispensed daily from the bulk formulation.


VEHICLE
- Justification for use and choice of vehicle (if other than water): Corn oil is a well-established vehicle for use with test substances for which water is not an appropriate vehicle.
- Concentration in vehicle: 0, 10, 30, 100 mg/ml
- Amount of vehicle (if gavage): 10 ml/kg
- Lot/batch no. (if required): 117K0127
- Purity: Not stated.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
duplicate samples were collected weekly from the middle stratum of each dosing formulation (including the control group). Samples collected from the first, fourth and last weekly formulations were analysed for concentration. All remaining samples were frozen and stored at approximately -20 deg C.
Duration of treatment / exposure:
Males Dosed during study Days 0-27 (14 days prior to pairing through to one day prior to scheduled euthanasia); a total of 28 doses.
Females: Dosed from study Day 0 through to the day prior to euthanasia (14 days prior to pairing through to Lactation Day 3); a total of 39-52 doses. Females with no evidence of mating or that failed to deliver were dosed through to the day prior to euthanasia (post-mating or post-cohabitation day 25) for a total of 44-52 doses.
Frequency of treatment:
Animals were dosed once daily. All animals were dosed at approximately the same time each day.
Duration of test:
Approximately 7.5 weeks.
Doses / concentrations
Remarks:
Doses / Concentrations:
0, 100, 300 and 1000 mg/kg/day
Basis:
other: (Nominal gavage dose. Actual gavage solution concentrations were 96-102% of nominal)
No. of animals per sex per dose:
12
Control animals:
yes, concurrent vehicle
Statistics:
Analyses were conducted using two-tailed tests (except as otherwise noted).
Prenatal mating, fertility, conception and copulation indices were analysed using the Chi-square test with Yates' correction factor. Histopathological findings were analysed by the Fisher's Exact test. Mean parental body weights, body weight changes and food consumption, offsprinig body weights and body weight changes, gestation lenghth, number og former implantation sites, number of pups born, live litter size on postnatal day 0, unaccounted for sites, absolute and relative organ weights and pre-coital intervals values were subjected to a parametric one-way analysis of variance (ANOVA) to determine intergroup differences. If ANOVA revealed significant intergroup variance, Dunnett's test was used to compare the test substance-treated groups to the control group. Mean litter proportions (percent per litter) of males at birth and postnatal survival were subjected to the Kruskal-Wallis nonparametric ANOVA to determine intergroup differences. If the ANOVA revealed significant intergroup variance, Dunn's test was used to compare the test substance-treated groups to the control group.

Results and discussion

Effect levels

open allclose all
Dose descriptor:
NOAEL
Remarks:
for systemic parental toxicity
Effect level:
1 000 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: NOAEL was highest dose tested
Dose descriptor:
NOAEL
Remarks:
for reproductive toxicity
Effect level:
1 000 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: NOAEL was highest dose tested
Dose descriptor:
NOAEL
Remarks:
for neonatal toxicity
Effect level:
1 000 mg/kg bw/day
Sex:
male/female
Basis for effect level:
other: NOAEL was highest dose tested

Observed effects

No test substance-related effects were observed on any of the evaluated parameters, including:
Survival; Clinical observations; Body weights; Food consumption; Reproductive performance (Male Mating Index, Female Mating Index, Male Fertility Index, Female Fertility Index, Male Copulation Index, Female Conception Index, Pre-Coital Interval); Gestation length and parturition; Gross pathology; Organs weights, Histopathology; Litter data; Postnatal survivial; General physical condition of pups; Body weight of pups; Necropsies of dead pups.

Applicant's summary and conclusion

Conclusions:
In the absence of test substance-related effects on reproductive performance, gestation length and parturition, a dosage level of 1000 mg/kg/day (the highest dose tested) is considered to be the NOAEL for reproductive toxicity of the test substance when administered orally by gavage to Crl:CD(SD) rats. The NOAEL for male and female parental toxicity is also considered to be 1000 mg/kg/day. Based on the absence of effects on postnatal survival or pup body weights, the NOAEL for neonatal toxicity is lso considered to be 1000 mg/kg/day.
Executive summary:

The test substance was tested for potential reproductive and developmental toxicity in a GLP study conducted in accordance with OECD Test Guideline 421. The test material, in corn oil, was administered by gavage to groups of 12 male and 12 female Sprague-Dawley rats at dosage levels of 0, 100, 300 and 1000 mg/kg/day. Males and females were dosed for 2 weeks prior to pairing and for the 2-week mating period. Females continued to be dosed throughout gestation to three days after birth. Mothers and pups were euthanised four days after birth. Males were euthanised the day following their last dose of test material. Females with no evidence of mating or that failed to deliver were dosed through to 25 days after mating/cohabitation and euthanised the following day.

No test material-related effects were observed on parental animals, reproductive performance, or offspring. The no-observed adverse effect level (NOAEL) for parental systemic toxicity, reproductive toxicity, and neonatal toxicity is in each case concluded to be 1000 mg/kg/day, the highest dose tested.