1,4-Cyclohexanedicarboxamide, N1,N1,N4,N4-tetrakis(2-hydroxyethyl)-, trans-

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014-04-01 to 2014-06-04

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 414 (Prenatal Developmental Toxicity Study)

Version / remarks:

adopted January 22, 2001

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.31 (Prenatal Developmental Toxicity Study)

Version / remarks:

Regulation (EC) No. 440/2008 (May 30, 2008)

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

(1r,4r)-N1,N1,N4,N4-tetrakis(2-hydroxyethyl)cyclohexane-1,4-dicarboxamide

EC Number:

700-597-4

Cas Number:

1215841-86-3

Molecular formula:

C16H30N2O6

IUPAC Name:

(1r,4r)-N1,N1,N4,N4-tetrakis(2-hydroxyethyl)cyclohexane-1,4-dicarboxamide

Constituent 2

Reference substance name:

CAS name: 1,4-Cyclohexanedicarboxamide, N1,N1,N4,N4-tetrakis(2-hydroxyethyl)-, trans

IUPAC Name:

CAS name: 1,4-Cyclohexanedicarboxamide, N1,N1,N4,N4-tetrakis(2-hydroxyethyl)-, trans

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

CAS name: 1,4-Cyclohexanedicarboxamide, N1,N1,N4,N4-tetrakis(2-hydroxyethyl)-, trans
Chemical characterization: Trans-N,N,N',N'-Tetrakis(2-hydroxyethyl)-cyclohexyl-1,4-diamide
Characteristics: Whitish, solid, powder, hydroscopic
Contents:
91.53 % Trans-N,N,N',N'-Tetrakis(2-hydroxyethyl)-cyclohexyl-1,4-diamide

Test animals

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

- Source: Charles River Laboratories, Research Models and Services, Germany GmbH Sandhofer Weg 7, 97633 Sulzfeld, Germany
- Age: 9 weeks
- Weight at study initiation: 218.9 - 278.5 g.
- Housing: single
- Diet: Pelleted maintenance diet, ad libitum, Commercial ssniff® R/Z V1324 (ssniff Spezialdiäten GmbH, 59494 Soest, Germany,
- Water: tap water, ad libitum
- Acclimation period: 13 days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 +/- 3 °C
- Humidity (%): 55 +/- 15 %
- Illumination: 12 hours artifical fluorescent light and 12 hours dark

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on exposure:

- Vehicle: Tap water
- Concentration in vehicle: 100mg / 300 mg / 1000 mg/kg b. w. /day
- Total volume applied: 10 ml/kg bw/treatment
- Test item preparation: Ttest item was dissolved in the vehicle (tap water) to the appropriate concentrations. The test item-formulations were
freshly prepared on each administration day
- Control: Control animals received the vehicle (tap water) at a constant volume of 10 mL/kg b.w. orally once daily in the same way
- Male rats: Male rats for mating remained untreated

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analysis of test item concentration revealed correctly prepared test item formulations. The actual concentrations of the test item within the
formulations were within the measured range of 100% and 105% of the nominal concentrations. No test item could be detected in any of the
control samples

Details on mating procedure:

- Sexually mature ('proved') male rats of the same breed served as partners.
- The female breeding partners were randomly chosen.
- Mating was monogamous: 1 male and 1 female animal were placed together in one cage during the dark period. Each morning a vaginal smear was
taken to check for the presence of sperm. If findings were negative, mating was repeated with the same partner. The day on which sperm was found
was considered as the day of conception (day 0 of pregnancy).
- This procedure was repeated until enough pregnant dams were available for all groups.
- Rats which did not become pregnant were excluded from the analysis of the results and replaced by other animals.
- A post-mortem negative staining according to SALEWSKI was carried out in the replaced animals in order to confirm the non-pregnancy status.

Duration of treatment / exposure:

- 1 mating day
- 14 administration days from gestation day 6 to 19

Frequency of treatment:

daily

Duration of test:

until day 20 post-coitum

Doses / concentrations

Remarks:

Doses / Concentrations:
100, 300, 1000 mg/kg bw/day
Basis:
nominal in water

No. of animals per sex per dose:

Treated animals: Groups 1 - 4: 25 animals per group
Evaluated litters: Groups 1 - 4: 20 litters per group

Control animals:

yes, concurrent vehicle

Details on study design:

- The dose levels were selected in agreement with the Sponsor based on the results of a 14-day dose-range-finding Study.
- In the dose-range finding study, test item was administered to female rats at dose levels of 100, 300 or 1000 mg/kg b.w./day orally, by gavage,
once daily for 14 days.
- Oral treatment with 100, 300 or 1000 mg test item/kg b.w./day did not cause any signs of systemic intolerance reactions during the course of
the study. The faeces were of normal consistency throughout the experimental period. None of the female rats died prematurely.
- Body weight and the body weight gain were not influenced at any tested dose level. No test item-related influence was noted on the food and
drinking water consumption.
- Macroscopic examination revealed no test item-related changes.
- For the present rat embryotoxicity study dose levels of 100, 300 or 1000 mg test item/kg b.w./day, administered orally, by gavage once
daily (at a constant volume of 10 mL/kg b.w./day) from the 6th to the 19th day of pregnancy, were selected in agreement with the Sponsor.

Examinations

Maternal examinations:

PARAMETERS ASSESSED DURING STUDY:
- Viability: daily (twice during treatment period)
- Clinical signs: daily (twice during treatment period)
- Body weight: day 0 of gestation (the day of detection of a positive mating sign), followed by daily weighing - always at the same time of the day
- Body weight change: 3-6, 6-9, 9-12, 12-15, 15-18 and 18-20, furthermore the net weight change from day 6 is given
- Food consumption: Quantity of food consumed by each rat was recorded daily
ORGANS EXAMINED AT NECROPSY (MACROSCOPIC AND MICROSCOPIC): Macroscopic examination of the internal organs and placentae of the
dams was carried out on the day of sacrifice

Ovaries and uterine content:

Examination of uterine content: Ovaries and the uteri of the dams were removed; the gravid uteri (in toto) were weighed

Fetal examinations:

Examination of the fetuses: The fetuses were removed and the following examinations performed:
- Macroscopic inspection (gross evaluation) of the placentae for example for focal indurations.
- The number of fetuses (alive and dead) and placentae (location in the uterus and the assignment of the fetuses) was determined.
- Sex and viability of fetuses were determined. Animals are said to be viable when they are found alive (spontaneous breathing, spontaneous
movement).
- Number and size of resorptions were determined.
- Corpora lutea in the ovaries, implantations and location of fetuses in the uterus were determined.
- Weights of fetuses and weights of the placentae were determined (fetuses were considered as runts if their weight was less than 70% of the
mean litter weight).
- Fetuses were inspected externally for damages, especially for malformations .
- The fetuses were sacrificed by an ether atmosphere.
Examination of fetuses and determination of number and kind of retardations, variations or malformations:
- 50% of the number of fetuses in each litter were examined for skeletal anomalies. The thorax and peritoneal cavity (without damage to ribs and
sternum) were opened and the location, size and condition of the internal organs were determined.
The skeleton was double-stained with Alcian blue for the examination of cartilage and with Alizarin red to reveal ossifications (according to
DAWSON). The skeletal system was examined (determination of the number and type of retardations, variations as well as malformations).
- The remaining 50% of the number of fetuses in each litter were examined for soft tissue anomalies. Body sections were made and examined
according to WILSON.
The fetuses were allocated to the evaluation of DAWSON or WILSON on an alternating basis.

Statistics:

Statistical analyses of the parametrical values captured by Provantis software were calculated using the following settings:
- Analysis of normal distribution and homogeneity of variances was performed by using the SHAPIRO-WILKS test and the BARTLETT test. Data not
normally distributed or with heterogeneous variances between the groups were stepwise log- or rank-transformed.
- One-way analysis of variance (ANOVA) was performed with non-transformed or log-transformed data. The KRUSKAL-WALLIS test was used for
rank-transformed data.
- In case of significant differences (found by ANOVA or KRUSKAL-WALLIS test), intergroup comparisons with the control group were made by
parametric or non-parametric DUNNETT multiple comparison tests (p ≤ 0.05 and p ≤ 0.01).
- Parametrical values not captured by Provantis (e.g. number and weight of the fetuses) were analysed by the DUNNETT test (p ≤ 0.05 and p ≤ 0.01).
Prior to the DUNNETT test homogeneity of variances was tested using the BARTLETT test. In case of heterogeneity of variances, the STUDENT's t-test was carried out (p ≤ 0.05 and p ≤ 0.01).
- Statistical analyses of non-parametrical data (e.g. resorption-, malformation-, variation and retardation rates) were performed using the
following settings:
FISHERs exact test, n < 100; (p ≤ 0.05 and p ≤ 0.01) or
chi2-test with Yates' correction for continuity, n ≤ 0.01 (p ≤ 0.05 and p ≤ 0.01)
- Significantly different data are indicated in the summary tables of the result sections of the report.

Historical control data:

No test item-related differences between the ratio of live male fetuses to live female fetuses were noted between the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.). All values were within the range of LPT background data.

Results and discussion

Results: maternal animals

Maternal developmental toxicity

Details on maternal toxic effects:

Maternal toxic effects:no effects

Details on maternal toxic effects:
Under the present test conditions, the no-observed-effect level (NOEL) was above 1000 mg test item/kg b.w./day for the dams.

Effect levels (maternal animals)

Dose descriptor:

NOEL

Effect level:

> 1 000 mg/kg bw/day

Basis for effect level:

other: maternal toxicity

Results (fetuses)

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
No embryotoxic properties of the test item were noted during external / internal, skeletal and soft tissue examination up to the highest tested dose
of 1000 mg test item/kg b.w./day by oral administration.

Effect levels (fetuses)

1

Dose descriptor:

NOEL

Effect level:

> 1 000 mg/kg bw/day

Basis for effect level:

other: embryotoxicity

2

Dose descriptor:

NOEL

Effect level:

> 1 000 mg/kg bw/day

Basis for effect level:

other: fetotoxicity

3

Dose descriptor:

NOEL

Effect level:

> 1 000 mg/kg bw/day

Basis for effect level:

other: teratogenicity

Fetal abnormalities

Abnormalities:

not specified

Overall developmental toxicity

Developmental effects observed:

not specified

Any other information on results incl. tables

RESULTS

Examination of the dams

Summary of animals examined

	Group 1 Control	Group 2 100 mg/kg	Group 3 300 mg/kg	Group 4 1000 mg/kg
Treated dams	25	25	25	25
Not pregnant dams	1	0	2	1
Dams without viable fetuses	0	0	1	0
Not examined dams (spare animals)	4	5	2	4
Evaluated litters	20	20	20	20

 

Summary of animals evaluated

Test item dose in mg/kg b.w./day, p.o.	Animal nos. of mated rats	Animal nos. of rats with evaluable litters at laparotomy	Dams not pregnant (animal nos.)	Dams with total implantation loss (animal nos.)	Reserve animals, not examined (animal nos.)
Control	1 - 25	1 - 13, 15 - 21	14	none	22 - 25
100	26 - 50	26 - 45	none	none	46 - 50
300	51 - 75	51 - 58, 60 - 63, 65, 67 - 73	59, 66	64	74, 75
1000	76 - 100	76 - 85, 87 - 96	86	none	97 -100

Behaviour, external appearance, faeces, mortality

No test item-related changes of behaviour or external appearance were noted in the dams treated orally with 100, 300 or 1000 mg test item/b.w./day. None of the dams died prematurely. The faeces were of normal consistency throughout the experimental period.

 

Body weight and body weight gain

No test item-related changes in body weight in comparison to the control group were noted for the dams of all treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.). The body weight change (examined in 3-day intervals) was similar to that of the control at all examined time points. The mean body weight gain from the start value (day 0 of pregnancy) was similar (plus 56% at 100 mg/kg, plus 50% at 300 mg/kg and plus 55% at 1000 mg/kg) to the body weight increase of the control dams at the time point of laparotomy on gestation day 20 (plus 56%).

 

Food and drinking water consumption

No test item-related changes in food consumption were noted between the dams of the control group and the dams treated orally with 100, 300 or 1000 mg test item/kg b.w./day. Drinking water consumption showed no test item-related changes at any tested dose level as observed during daily visual appraisal.

 

Examination of the dams at termination

Necropsy findings

Macroscopic inspection of the internal organs of the dams at laparotomy revealed no changes in the control and the test item-treated groups(100, 300 or 1000 mg test item/kg b.w./day.

Uterus weight and net body weight change

No test item-related changes in the gravid uterus weight, the carcass weight and the net weight change from day 6 onwards (carcass weight minus day 6 body weight) in comparison to the control group were noted for the dams of all treatment groups(100, 300 or 1000 mg test item/kg b.w./day, p.o.

 

Organ weights

No test item-related changes in the absolute or relative organ weights of heart, liver or kidneys were noted in comparison to the control group for the dams treated orally with 100, 300 or 1000 mg test item/kg b.w./day.

Reproduction data of the dams

No test item-related influence was detected on the prenatal fetal development at100, 300 or 1000 mg test item/kg b.w./day, p.o.with respect to the implantation sites, resorptions, number of live fetuses, the values calculated for the post-implantation loss and the sex distribution of fetuses when compared to the control.

At 300 mg test item/kg b.w./day, p.o., a total post-implantation loss (one early resorption) was noted in one dam (no. 64). This

finding is known to occur spontaneously and is considered as not test item-related.

The statistical analyses of the parameters of reproduction were performed by comparison of the ratios of:

-	implantation sites/corpora lutea (described as pre-implantation loss)
-	resorptions/implantation sites
-	live fetuses/implantation sites (described as post-implantation loss)

 

Examination of the fetuses

Mortality

No dead fetuses were noted in the litters of the dams of the control group and in the litters of the dams treated orally with 100, 300 or 1000 mg test item/kg b.w./day.

 

Sex distribution of the fetuses

No test item-related differences between the ratio of live male fetuses to live female fetuses were noted between the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.). All values were within the range of LPT background data.

 

Weight of placentae

No test item-related differences of the placental weights were noted between the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

 

 

Weight of the fetuses

No test item-related differences of the fetal weights were noted between the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

Slight but statistically significant increases in the mean fetal weights of the female fetuses (by 5.7%) were noted for the fetuses of the intermediate dose group. Nevertheless, an increase in the weight of the fetuses is not an adverse effect and is considered as spontaneous.

 

In total, five runts were noted at laparotomy: four runts were found at 100 mg test item/kg b.w./day and one runt at 300 mg test item/kg b.w./day. The afore-mentioned findings are regarded to be spontaneous, the incidences are within the spontaneous range of variability.

 

 

External and internal macroscopic examination of the fetuses at laparotomy

External examination

Malformations

No test item-related macroscopically visible malformations were noted for the fetuses of the treatment groups (100, 300 or 1000 mgtest item/kg b.w./day, p.o.) during the external examination of the fetuses at laparotomy.

External inspection of the litter of the low dose dam no. 28 (100 mg test item/kg b.w./day, p.o.) revealed one fetus (runt no. 13 m) with a short tail (brachycaudia). This finding is known to occur spontaneously in rats of this strain and is within the LPT background data according to type and incidence and hence, is not considered to be related to the test item-treatment with but is regarded to be spontaneous according to type and incidence.

Variations

No macroscopically visible variations were noted for the fetuses of the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.) during the external examination of the fetuses at laparotomy.

 

Internal examination

A macroscopic internal examination was performed to detect gross changes of the internal organs.

No malformations or variations were noted during the examination for the fetuses of the control group and the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

 

Skeletal examination of the fetuses

Malformations

No malformations were noted during skeletal examination according to DAWSON at any tested dose level (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

Variations

No test item-related increase in the incidence of skeletal variations in comparison to the control group was noted in any of the test item treated groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

The skeletal variations observed were related to the sternum (sternebra(e) bipartite or misaligned to a slight degree), the rib(s) (rib(s) short or wavy, accessory 14th rib(s)), the lumbar vertebral bodies (accessory lumbar vertebral body) or os pubis (bipartite). All findings are regarded to be spontaneous.

The following slight but statistically significant increase in the fetal incidence of variations of the ribs was noted which is not considered to be test item-related as given in the Table below.

Skeletal variation		Mean value observed in this study [fetal incidence in%]	LPT Background Data# range of mean values per group [fetal incidence in mean %] (n=55 control or n= 141 test item groups; Data taken from 2000 to July 2014
Rib(s) short		Control:    0.0 Group 2:   0.0 Group 3:   0.0 Group 4:   3.1*	0.0 - 6.2 0.0 - 4.8	(control) (test item groups)
#:	not audited by QAU
	(p ≤ 0.05 / p ≤ 0.01) Fisher or Chi^2- test

Retardations

No test item-related influence was noted on the incidence of skeletal retardations at 100, 300 or 1000 mg test item/kg b.w./day, p.o. The observed skeletal retardations were related to the skull (incomplete ossification of frontal, parietal, interparietal and/or supraoccipital areas), the hyoid (unossified), the sternum (sternebra(e) incompletely ossified, reduced in size or unossified), the thoracic vertebral bodies(bipartite or dumbbell-shaped), the sacral vertebral bodies(unossified), the caudal vertebral bodies(only one body ossified or all bodies unossified), the os ischii (incompletely ossified or unossified), the os pubis (incompletely ossified or unossified) and the metacarpalia and metatarsalia (absence of ossification in metacarpalia 2 to 5 and metatarsalia 2 to 5). All incidences were in the range of LPT background data.

The following statistically significant differences in fetal incidence of skeletal retardations were noted in test groups 2, 3 and 4 (damstreated with 100, 300 or 1000 mg test item/kg b.w./day, p.o.) which are not considered to be test item-related as given in the Table below. They are well within the range of LPT background data, appeared without any dose response relationship and/or represent a decrease compared to the control.

Skeletal retardations				Mean value observed in this study [fetal incidence in%]	LPT Background Data# range of mean values per group [fetal incidence in mean %] (n=55 control or n= 141 test item groups; Data taken from 2000 to July 2014
Skull incomplete ossification				Control:  14.0 Group 2: 27.4** Group 3: 20.7 Group 4: 18.3	1.4 - 71.3 (control) 1.4 - 79.5 (test item groups)
Sternebra(e) incompletely ossified				Control:  20.2 Group 2: 14.1 Group 3:   5.8** Group 4: 16.0	5.5 - 86.2 (control) 0.0 - 91.4 (test item groups)
Sternebra(e) reduced in size				Control:  62.0 Group 2: 48.1* Group 3: 53.7 Group 4: 50.4*	9.3 - 66.7 (control) 4.5 - 74.1 (test item groups)
Sternebra(e) unossified				Control:  68.2 Group 2: 75.6 Group 3: 67.8 Group 4: 55.7*	5.8 - 91.9 (control) 1.2 - 88.5 (test item groups)
Absence of ossification in metacarpalia 2 to 5				Control:  79.8 Group 2: 89.6* Group 3: 71.9 Group 4: 84.0	0.0 - 94.9 (control) 0.0 - 97.6 (test item groups)
Absence of ossification in metatarsalia 2 to 5				Control:    3.9 Group 2:   5.9 Group 3:   9.9* Group 4:   6.1	0.0 - 42.3 (control) 0.0 - 37.6 (test item groups)
Sacral vertebral body/ bodies unossified				Control:    0.0 Group 2:   0.7 Group 3:   1.7 Group 4:   3.1*	0.0 - 20.8 (control) 0.0 - 12.4 (test item groups)
#:		not audited by QAU
		*/**: (p ≤ 0.05 / p ≤ 0.01) Fisher or Chi^2- test

Soft tissue examination of the fetuses

Malformations

No test item-related malformations were noted during soft tissue examinations of the fetuses according to WILSON in the control group and in any of the treatment groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

Soft tissue examination confirmed the afore-mentioned spontaneous external malformation in form of brachycaudia in one fetus (runt no. 13 m) of the low dose dam no. 28 (100 mg test item/kg b.w./day, p.o.).

 

Variations

No test item-related differences in the incidences of the observed soft tissue variations were noted between the control group and

the test item treated groups (100, 300 or 1000 mg test item/kg b.w./day, p.o.).

Soft tissue variations were noted in the cerebral ventricle (dilatation of the 4th ventricle, seldomly of the 2nd or 3rd ventricle), the kidneys (uni- or bilateral dilatation of the renal pelvis or misplacement), the liver (haemorrhagic focus/foci) and the adrenal glands (dark discoloured). All incidences were in the range of LPT background data.

The following statistically significant difference in fetal incidence is not considered to be test item-related as given in the Table below.

Soft tissue variations				Mean value observed in this study [fetal incidence in%]	LPT Background Data# range of mean values per group [fetal incidence in mean %] (n=55 control or n= 141 test item groups; Data taken from 2000 to July 2014
Dilatation of renal pelvis				Control:    7.0 Group 2:   5.9 Group 3:   0.0** Group 4:   6.8	0.0 - 11.1 (control) 0.0 - 11.8 (test item groups)
#:		not audited by QAU
*/**:		(p ≤ 0.05 / p ≤ 0.01) Fisher or Chi^2- test

ABSTRACT and ASSESSMENT of fetal external / internal, skeletal observations and soft tissue observations

No test item-related macroscopically visible malformations, variations or retardations were noted at 100, 300 or 1000 mg test item/kg b.w./day, p.o.

No dead fetuses were detected at laparotomy either in the test item groups or the control group.

No test item-related increase was noted for the incidence of runts. In total, five runts were noted at laparotomy: four runts were

found at 100 mg test item/kg b.w./day and one runt at 300 mg test item/kg b.w./day.All afore-mentionedincidences are regarded to be spontaneous and are within the range of LPT background data.

No test item-related malformations were noted during external examination of the fetuses at dose levels of 100, 300 or 1000 mg test item/kg b.w./day, p.o.

External inspection revealed one runt with a short tail (brachycaudia) at 100 mg test item/kg b.w./day, p.o. This finding was

confirmed by soft tissue examination. Brachycaudia is known to occur spontaneously in rats of this strain and is within the LPT background data according to type and incidence and hence, is not considered to be related to the test item-treatment with but is regarded to be spontaneous according to type and incidence.

No malformations were noted in the fetuses during internal examination at laparotomy, skeletal examination (according to DAWSON) or soft tissue examination(according to WILSON) at any tested dose level.

No test-item related variations were noted in the fetuses during external / internal macroscopic inspection at laparotomy or soft tissue examination (according to WILSON) at any tested dose level. Skeletal examination (according to DAWSON) revealed no test item-related variations or retardations.

All further prenatal changes noted are without any biological relevance.

 

 

Applicant's summary and conclusion

Conclusions:

In conclusion, no embryotoxic properties of the test item were noted during external / internal, skeletal and soft tissue examination up to the highest tested dose of 1000 mg test item/kg b.w./day by oral administration.
The test item did not possess any teratogenic effect. The no-observed effect level (NOEL) for teratogenicity was above 1000 mg test item/kg b.w./day.

Executive summary:

Aim of the study is the examination of the influence of the test item administered orally during the critical period of organogenesis and the fetal development (6th to 19th day of gestation) on the pregnant rat and the fetus.

In this rat embryotoxicity study, the test item was administered to female rats at dose levels of 100, 300 or 1000 mg/kg b.w./day (administration volume: 10 mL/kg b.w./day), orally by gavage from the 6th to 19th day of pregnancy. Under the present test conditions, the no-observed-effect level (NOEL) was above 1000 mg test item/kg b.w./day for the dams. The no-observed-effect level (NOEL) for the fetal organism was also above 1000 mg test item/kg b.w./day. No test item-related malformation was noted at any of the test item treated groups. There was no test item-related increase in the incidence of fetal external / internal, skeletal or soft tissue variations or skeletal retardations at any tested dose level. In conclusion, no embryotoxic properties of the test item were noted during external / internal, skeletal and soft tissue examination up to the highest tested dose of 1000 mg test item/kg b.w./day by oral administration. The test item did not possess any teratogenic effect. The no-observed effect level (NOEL) for teratogenicity was above 1000 mg test item/kg b.w./day.