Registration Dossier

Administrative data

Endpoint:
toxicity to reproduction: other studies
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
July 25, 2000 to August 25, 2000
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: This study was not performed according to a guideline (rangefinding study), but was conducted under GLP conditions.
Cross-reference
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002
Report Date:
2002

Materials and methods

Test guideline
Qualifier:
no guideline available
Principles of method if other than guideline:
In this dose range-finding study, groups of pregnant female rats were gavaged with various doses of test substance on gestation days 7-17 and observed for adverse clinical signs. On gestation day 21, all surviving rats were euthanized and examined for distribution of corpora lutea, implantation sites, and uterine content. Parental animals underwent gross necropsy and foetuses were weighed and examined.
GLP compliance:
yes (incl. certificate)
Type of method:
in vivo

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent
Test material form:
liquid

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
female
Details on test animals and environmental conditions:
Crl:CD®(SD)IGS BR VAF/Plus®rats weighed 200-225 g at receipt and were about 60 days old. Pregnant animals were individually housed in stainless steel, wire-bottomed cages at a room temperature of 18-26C with a relative humidity of 30-70%, at least 10 air changes per hour, and a 12-hour light/dark cycle. Rats were fed Certified Rodent Diet #5002 (PMI Nutrition International) and given water ad libitum.

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on exposure:
Rats were gavaged with 240, 480, 960, or 1920 mg/kg bw/day on gestation days 7-17.
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Samples (2 ml) of test substance were taken on first and last day of dosing for analysis. No further information available.
Duration of treatment / exposure:
Day 7-17 of gestation
Frequency of treatment:
Daily
Duration of test:
21 days
Doses / concentrations
Remarks:
Doses / Concentrations:
240, 480, 960, and 1920 mg/kg bw/day
Basis:
actual ingested
No. of animals per sex per dose:
8
Control animals:
other: 2 ml of reverse osmosis deionized water (8 rats)
Details on study design:
Groups of pregnant rats (8/dose group) were gavaged with 0 (control), 240, 480, 960, or 1920 mg/kg bw/day on gestation days 7-17 at dosage volumes of 2.0, 0.25, 0.5, 1.0, and 2.0 ml/kg bw, respectively. Viability (2x daily), abnormal clinical signs (daily), body weights (daily), and feed consumption (gestation days 0, 7, 10, 12, 15, 18, and 21) were recorded. Mating performance was assessed. On gestation day 21, surviving rats were euthanized by carbon dioxide asphyxiation, caesarean sections were performed to remove the foetuses and examine the number and distribution of corpora lutea, implantation sites, live and dead foetuses, and early and late resorptions and parental animals underwent gross necropsy of the thoracic, abdominal and pelvic viscera. Live foetuses were euthanized with an intraperitoneal injection of Beuthanasia®-D Special. Sex and body weight of foetuses were recorded and any gross alterations were noted and these carcasses were fixed in Bouin’s solution. Only body weights of live foetuses were used to calculate foetal body weight averages. Animals found dead or moribund were examined for gross lesions, pregnancy status, and uterine contents.
Statistics:
Averages and percentages were calculated and litter values were used where appropriate.

Results and discussion

Observed effects

One high-dose rat was moribund sacrificed on gestation day 16, but all other animals survived to termination. Clinical signs in the moribund animal included urine-stained abdominal fur; dry, red perioral substance; amber-coloured urine, excess salivation; dry, red substance on fur; and red perivaginal substance. Necropsy showed normal tissues and the litter consisted of 2 early resorptions and 17 normal foetuses. All treated rats had chromorhinorrhea, excess salivation, and a dried red or red perioral substance. The 2 highest dose groups showed urine-stained abdominal fur and a dried red or red perivaginal substance. At the high dose, rats had amber coloured urine. Other incidental clinical signs included rales, soft or liquid faeces and localized alopecia. Body weight changes tended to be slightly reduced (no statistics) in the higher dosed animals through part or all of treatment otherwise body weights and body weight changes were comparable to that of controls throughout the study. Feed consumption followed a similar pattern. Necropsy of the dams and examination of the litters (i.e., corpora lutea, implantations, litter sizes, live foetuses, early and late resorptions, percent resorbed conceptuses, foetal body weights, and percent live male foetuses) revealed no differences in any of the test groups including controls. At the 2 highest doses, slight reduction (no statistics) in average foetal body weight was noted, but was considered to be related to larger litter size and was not considered treatment related.

Applicant's summary and conclusion

Conclusions:
Based on these results, the recommended dose levels for the main developmental toxicity study were 240, 480, and 960 mg/kg bw/day.
Executive summary:

Groups of pregnant rats (8/dose group) were gavaged with 0 (control), 240, 480, 960, and 1920 mg/kg bw/day on gestation days 7-17. On gestation day 21, all surviving rats were euthanized and examined for distribution of corpora lutea, implantation sites, and uterine content. Parental animals underwent gross necropsy and foetuses were weighed and examined. Body weights, body weight change, and feed consumption were generally comparable to those of controls throughout the study. Necropsy of the dams and examination of the litters revealed no differences in any of the test groups including controls. The recommended dose levels for the main developmental toxicity study were 240, 480, and 960 mg/kg bw/day.