Registration Dossier

Administrative data

Endpoint:
developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2007
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study not conducted under GLP conditions, but followed sound scientific principles.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: Custom protocol
Principles of method if other than guideline:
The test material was prepared daily by dilution in deionized water (vehicle) to the appropriate concentrations accounting for the concentration of the stock solution and specific gravity. Test material was administered once daily via oral gavage at 0 (vehicle), 10, 30, 90, 270 and 500 mg/kg to 10 female rats per group beginning on the first day of presumed gestation (DG 0) and continuing through the day of delivery or DG 24 for rats that did not deliver a litter. The following maternal (F0 generation) parameters were recorded: clinical observations (daily and select times postdose through delivery, then on days of lactation DL 1, 4 and 6); body weights and feed consumption (daily DG 0 through necropsy); and necropsy (DL 6 or DG 24 for rats with no litter; select tissues collected and implantations recorded). The following litter (F1 generation) parameters were recorded: gestation (monitored continually for 12 hours/day and at 2300, 0200 and 0500 daily); parturition time; litter size; pup viability; clinical observations (daily: DL 1 to DL 6); body weights (DL 1, 4, and 6); and necropsy (post-natal day 6 for gross lesions)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: Liquid
Details on test material:
- Name of test material (as cited in study report): MTDID 6675
- Substance type: Clear colorless liquid
- Physical state: Liquid
- Analytical purity: 98.6% as solids
- Composition of test material, percentage of components: 29.9 +/- 0.1% active ingredient in water.
- Purity test date: 12 December 2006
- Lot/batch no.: 140499-19/10
- Storage condition of test material: Room temperature

Test animals

Species:
rat
Strain:
other: Sprague Dawley Crl:CD(SD)
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Inc.
- Sex: female
- Age at study initiation: Approx 65 days
- Weight at study initiation: Approx. 233 to 237g
- Fasting period before study: None
- Housing: Standard steel wire-bottom cage, nesting boxes from Gestation day 20
- Diet (e.g. ad libitum): Certified Rodent Diet # 5002 (PMI Nutrition Intl.)
- Water (e.g. ad libitum): ad libitum
- Acclimation period: No data
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-26
- Humidity (%): 30-70
- Air changes (per hr): At least 10/hour
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 5 mL/kg
- Concentration (if solution): 0, 2, 6, 18, 54, 100 mg/mL (active ingredient)
- Constant volume or concentration used: no
Analytical verification of doses or concentrations:
not specified
Details on mating procedure:
Females cohabited with males for up to 5 days pior to study initiation.
Duration of treatment / exposure:
Test article administered by oral gavage once daily.
Frequency of treatment:
Treatment occurred through the day of delivery or day 24 (rats that do not deliver a litter).
Duration of test:
Gestation day 0 through lactation day 6.
No. of animals per sex per dose:
10
Control animals:
yes, concurrent vehicle
Details on study design:
- Pups from F0 generation rats were observed for 6 days after birth and euthanized for necropsy
- Dose selection rationale: based on previous studies
- Rationale for animal assignment (if not random): Random

Examinations

Maternal examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Hourly for 4 hours post-dose each day.
- Cage side observations: mortality, motor acitivity, righting reflex, chromodacryorrhea, chromorhinorrhea, ptosis, lacrimation, perinasal substance, low carriage, dehydration, temperature to touch, extremity appearance, posture, discoloration, delivering, perivaginal substance, alopecia, perioral substance, rales, bradypnea, coat grooming, coat appearance.
DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Hourly for 4 hours post-dose each day.
BODY WEIGHT: Yes
- Time schedule for examinations: Weekly during the acclimation period and on DG0, daily during the dosage period, daily during the postdosage period and on the day of euthanasia.
POST-MORTEM EXAMINATIONS: Yes
- Sacrifice on gestation day # 25
- Organs examined: Lungs, trachea, esophagus, heart, liver, kidneys, stomach, uterus, and spleen
Ovaries and uterine content:
The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: No
- Number of corpora lutea: no
- Number of implantations: Yes
- Number of early resorptions: Yes
- Number of late resorptions: Yes
Fetal examinations:
- External examinations: Yes: all per litter
- Soft tissue examinations: Yes: all per litter
- Skeletal examinations: No data
- Head examinations: Fetal head examinations were performed. Cross sections of brain were examined for apparent hydrocephaly.

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:
Maternal toxic effects:yes

Details on maternal toxic effects:
Two F0 generation female rats in the 500 mg/kg/day dosage group were found dead on day 2 of dosing. Four F0 generation female rats in the 270 mg/kg/day dosage group were found dead on day 3 and 5. One rat in this group was euthanized due to adverse clinical condition on day 21.

Effect levels (maternal animals)

Key result
Dose descriptor:
NOAEL
Effect level:
ca. 30 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
other: Generation: F0 and F1, female. NOAEL based on maternal body weight and feed consumption, reduction in pup weight, shortened parturition time, pup death, and decreased pup weights.

Results (fetuses)

Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:yes

Details on embryotoxic / teratogenic effects:
The number of stillborn pups found dead or presumed cannibalized was increased compared to controls. The live litter sizes, pup weights and surviving pups were decreased in the 270 mg/kg/day group as compared to controls.

Effect levels (fetuses)

Key result
Dose descriptor:
NOAEL
Effect level:
ca. 30 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: No test material-related findings were noted in the 30 mg/kg dose group pups.

Fetal abnormalities

Abnormalities:
not specified

Overall developmental toxicity

Developmental effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
There were no test material related findings in the 10 and 30 mg/kg dose groups. Based on the results of this study, the no observable adverse effect level (NOAEL) for both maternal and developmental toxicity was 30 mg/kg MTDID 6675.
Executive summary:

The developmental toxicity of the test article (supplied at 29.9 ± 0.1% in water, lot 140499 19/10) was evaluated in Sprague Dawley rats following a custom protocol. The test material was prepared daily by dilution in deionized water (vehicle) to the appropriate concentrations accounting for the concentration of the stock solution and specific gravity. Test material was administered once daily via oral gavage at 0 (vehicle), 10, 30, 90, 270 and 500 mg/kg to 10 female rats per group beginning on the first day of presumed gestation (DG 0) and continuing through the day of delivery or DG 24 for rats that did not deliver a litter. The following maternal (F0 generation) parameters were recorded: clinical observations (daily and select times postdose through delivery, then on days of lactation DL 1, 4 and 6); body weights and feed consumption (daily DG 0 through necropsy); and necropsy (DL 6 or DG 24 for rats with no litter; select tissues collected and implantations recorded). The following litter (F1 generation) parameters were recorded: gestation (monitored continually for 12 hours/day and at 2300, 0200 and 0500 daily); parturition time; litter size; pup viability; clinical observations (daily: DL 1 to DL 6); body weights (DL 1, 4, and 6); and necropsy (post-natal day 6 for gross lesions). The 500 mg/kg dose group was terminated on DG 2 due to mortality (2/10 rats) and adverse clinical signs (10/10 rats). At 270 mg/kg, mortality (4/10 rats), adverse clinical signs, and decreased maternal body weight and feed consumption were observed during the gestation period; body weight rebounded during the lactation period in this group. The 270 mg/kg dose group also had shortened parturition time, pup death and decreased pup weights. At 90 mg/kg, maternal body weight and feed consumption were reduced during the gestation period; body weight rebounded during the lactation period. The 90 mg/kg dose group also had decreased pup weight. There were no test material related findings in the 10 and 30 mg/kg dose groups. In conclusion based on the results of this study, the no observable adverse effect level (NOAEL) for both maternal and developmental toxicity was 30 mg/kg of the test article.