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Toxicity to reproduction

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Administrative data

Endpoint:
screening for reproductive / developmental toxicity
Remarks:
based on test type (migrated information)
Type of information:
experimental study
Adequacy of study:
key study
Study period:
16 Sep 2014 - 26 May 2015
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP-compliant guideline study
Cross-reference
Reason / purpose for cross-reference:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2015
Report date:
2015

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)
Qualifier:
according to guideline
Guideline:
other: EPA, Health Effects Test Guidelines; OPPTS 870.3650
GLP compliance:
yes (incl. QA statement)
Limit test:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
Etocrilene
EC Number:
226-029-0
EC Name:
Etocrilene
Cas Number:
5232-99-5
Molecular formula:
C18H15NO2
IUPAC Name:
etocrilene
Test material form:
solid
Details on test material:
- Physical state: solid/white

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH
- Age at study initiation: 11 - 13 weeks
- Weight at study initiation: Male animals: 328.2 g - 368.9 g; Female animals: 190.2 g - 215.9 g
- Housing: individually in Polycarbonate cages type III; during overnight matings, male and female mating partners were housed together in Polycarbonate cages type III. Pregnant animals and their litters were housed together until PND 4.
- Diet: ground Kliba maintenance diet mouse/rat “GLP” meal, ad libitum
- Water: supplied from water bottles (ad libitum).
- Acclimation period: 6 days

ENVIRONMENTAL CONDITIONS
- Temperature: 20-24°C
- Humidity (%): 30-70
- Air changes (per hr): 115
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
CMC (carboxymethyl cellulose)
Remarks:
1%
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:
For the preparation of the administration suspensions the test substance was weighed in a calibrated beaker depending on the dose group, topped up with 1% Carboxymethylcellulose suspension in drinking water and intensely mixed with a homogenizer. During administration, the preparations were kept homogeneous with a magnetic stirrer.

VEHICLE
- Concentration in vehicle: 1.00, 3.00 and 10.00 g/100ml
- Amount of vehicle (if gavage): 10 ml/kg bw
Details on mating procedure:
- M/F ratio per cage: 1:1
- Length of cohabitation: maximum of 2 weeks
- Proof of pregnancy: sperm in vaginal smear referred to as day 0 of pregnancy
- After successful mating each pregnant female was caged (how): individually
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Analytical verifications of the stability of the test substance in 1% Carboxymethylcellulose suspension in drinking water for a period of 96 hours at room temperature were carried out prior to the start of the study. Samples of the test substance preparations were sent to the analytical laboratory once during the study period for verification of the concentration. The samples, which were taken for the concentration control analysis at the beginning of the administration period, were also used to verify the homogeneity. Three samples (one from the top, middle and bottom in each case) were taken from the beaker with a magnetic stirrer running. Of each sample, one additional reserve sample was retained. Details of the sampling schedule were recorded with the raw data.
The various analyses:
• Demonstrated the stability of the test substance in 1% Carboxymethylcellulose suspension in drinking water over a period of 96 hours at room temperature
• Confirmed the homogeneous distribution of the test substance in 1% Carboxymethylcellulose suspension in drinking water
• Verified correct concentrations of the test substance preparations.
Duration of treatment / exposure:
The duration of treatment covered a 2-week pre-mating and a mating period in both sexes, approximately 4 days post-mating in males, and the entire gestation period as well as approximately 4 weeks of the lactation period.
Frequency of treatment:
daily
Doses / concentrations
Remarks:
Doses / Concentrations:
100, 300, 1000 mg/kg bw
Basis:
actual ingested
No. of animals per sex per dose:
10
Control animals:
yes, concurrent vehicle

Examinations

Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: A check for moribund or dead animals was made twice daily on working days or once daily (Saturday, Sunday or on public holidays). A cageside examination was conducted at least once daily for any signs of morbidity, pertinent behavioral changes and signs of overt toxicity.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Detailed clinical observations (DCO) were performed in all animals once prior to the first administration (day 0) and at weekly intervals during the administration period. The examinations started in the morning. The findings were ranked according to the degree of severity, if applicable.

BODY WEIGHT: Yes
In general, the body weight of the male and female parental animals was determined once a week at the same time of the day (in the morning) until sacrifice. The following exceptions are notable for the female animals:
• During the mating period the parental females were weighed on the day of positive evidence of sperm (GD 0) and on GD 7, 14 and 20.
• Females with litter were weighed on the day of parturition (PND 0) and on PND 4.
Females without positive evidence of sperm, without litter or waiting for necropsy, were weighed weekly. These body weight data were solely used for the calculations of the dose volume.

FOOD CONSUMPTION
Generally, food consumption was determined once a week for male and female parental animals, with the following exceptions:
• Food consumption was not determined after the 2nd premating week (male parental animals) and during the mating period (male and female F0 animals).
• Food consumption of the F0 females with evidence of sperm was determined on gestation days (GD) 0 - 7, 7 - 14, and 14 - 20.
• Food consumption of F0 females which gave birth to a litter was determined on PND 1 - 4.
Food consumption was not determined in females without positive evidence of sperm during the mating and the gestation period and in females without litter during the lactation period.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: study day 32 (males) and 56 (females).
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes
- How many animals: 5 male and 5 female animals (with litter) per group
- Parameters examined: Leukocyte count (WBC), Erythrocyte count (RBC), Hemoglobin (HGB), Hematocrit (HCT), Mean corpuscular volume, (MCV),
Mean corpuscular hemoglobin (MCH), Mean corpuscular hemoglobin concentration (MCHC), Platelet count (PLT), Differential blood count, Reticulocytes (RET), Prothrombin time (Hepato Quick’s test) (HQT).

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: study day 32 (males) and 56 (females).
- Animals fasted: Yes
- How many animals: 5 male and 5 female animals (with litter) per group
- Parameters examined: Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Alkaline phosphatase (ALP), γ-Glutamyltransferase (GGT), Sodium (NA), Potassium (K), Chloride (CL), Inorganic phosphate (INP), Calcium (CA), Urea (UREA), Creatinine (CREA), Glucose (GLUC), Total bilirubin (TBIL), Total protein (TPROT), Albumin (ALB), Globulins (GLOB), Triglycerides (TRIG), Cholesterol (CHOL), Bile acids (TBA)

URINALYSIS: Yes
- Time schedule for collection of urine: Urinalysis was carried out on urine from 5 male and 5 female animals (with litter) per group on study day 30 (males) and 52 (females).
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Parameters examined: pH, Protein (PRO), Glucose (GLU), Ketones (KET), Urobilinogen (UBG), Bilirubin (BIL), Blood, Specific gravity, Sediment, Color, turbidity (COL, TURB), Volume (VOL)

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: On study day 28, a functional observational battery and motor activity measurement were carried out in five male animals per group. On study day 50, a functional observational battery and motor activity measurement were carried out in five female animals (with litter) per group.
- Battery of functions tested: Home cage observations, Open field observations, Sensory motor tests/Reflexes, Motor activity measurement
Sperm parameters (parental animals):
Stages of spermatogenesis in the testes
Litter observations:
All pups delivered from the F0 parents (F1 litter) were examined as soon as possible on the day of birth to determine the total number of pups, the sex and the number of liveborn and stillborn pups in each litter. At the same time, the pups were also being examined for macroscopically evident changes. Pups, which died before this initial examination, were defined as stillborn pups. In general, a check was made for any dead or moribund pups twice daily on workdays (once in the morning and once in the afternoon) or as a rule, only in the morning on Saturdays, Sundays or public holidays. The number and percentage of dead pups on the day of birth (PND 0) and of pups dying between PND 1-4 (lactation period) were determined. The number of live pups/litter was calculated on the day after birth, and on lactation day 4. On the day of birth (PND 0) the sex of the pups was determined by observing the distance between the anus and the base of the genital tubercle; normally, the anogenital distance is considerably greater in male than in female pups. The sex of the pups was finally confirmed at necropsy. The live pups were examined daily for clinical symptoms (including gross-morphological findings) during the clinical inspection of the dams and documented for each pup. The pups were weighed on the day after birth (PND 1) and on PND 4. Pups' body weight change was calculated from these results.

GROSS EXAMINATION OF DEAD PUPS:
All stillborn pups and all pups that died before PND 4 were examined externally, eviscerated and their organs were assessed macroscopically.
Postmortem examinations (parental animals):
GROSS PATHOLOGY: Yes
All parental animals were sacrificed by decapitation under isoflurane anesthesia. The exsanguinated animals were necropsied and assessed by gross pathology, special attention being given to the reproductive organs.

ORGAN WEIGHTS
The following weights were determined in all animals sacrificed on schedule: Anesthetized animals, Epididymides, Testes
The following weights were determined in 5 animals/sex and test group (females with litters, same animals as used for clinical pathology examinations): Adrenal glands, Brain, Heart, Kidneys, Liver, Spleen, Thymus

HISTOPATHOLOGY: Yes
see table below for details. Special attention was given on the stages of spermatogenesis in the testes.
Postmortem examinations (offspring):
All pups with scheduled sacrifice on PND 4 were sacrificed under isoflurane anesthesia with CO2. All pups were examined externally and eviscerated; their organs were assessed macroscopically. All pups without notable findings or abnormalities were discarded after their macroscopic evaluation. Animals with notable findings or abnormalities were evaluated on a case-by-case basis, depending on the type of finding.
Statistics:
• DUNNETT-test (twosided): Food consumption (parental animals), body weight and body weight change (parental animals and pups; for the pup weights, the litter means were used), gestation days.
• FISHER'S EXACT test (one-sided): Male and female mating indices, male and female fertility indices, females mated, females delivering, gestation index (females with liveborn pups), females with stillborn pups, females with all stillborn pups.
• WILCOXON test (one-sided) with BONFERRONI-HOLM adjustment: Mating days until day 0 pc, %postimplantation loss, pups stillborn, %perinatal loss, Implantation sites, pups delivered, pups liveborn, live pups day x, viability Index, Urinalysis parameters (apart from pH, urine volume, specific gravity, color and turbidity.
• WILCOXON test (twosided): % live male day x, %live female day x
• KRUSKAL-WALLIS test (two-sided): Rearing, grip strength of forelimbs and hindlimbs, landing foot-splay test, motor activity, Blood parameters, Urine pH, volume, specific gravity, color and turbidity, Weight parameters (pathology)
Reproductive indices:
Male mating index, Male fertility index, Female mating index, Female fertility index, Gestation index, Live birth index, Postimplantation loss
Offspring viability indices:
Viability index, Sex ratio

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:
effects observed, non-treatment-related
Description (incidence and severity):
There were no test substance-related or spontaneous mortalities in any of the groups. No clinical signs or changes of general behavior, which may be attributed to the test substance, were detected in any male or female F0 generation parental animal during the entire study period.
Dermal irritation (if dermal study):
not examined
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Description (incidence and severity):
While in the mean body weights of the high-dose parental males were without statistical significance nearly comparable to the concurrent control values, the body weight change of this group was statistically significantly below the concurrent control values during premating days 0 - 7 and 0 - 13 (about 27% and 29%, respectively).
The mean body weights of the high-dose parental females were statistically significantly below the concurrent control values on premating day 13 (about 4%), during GD 7 - 14 (up to 6%) and on PND 4 (about 6%). The body weight change of the high-dose parental females was statistically significantly below the concurrent control values during premating days 7 - 13 and 0 - 13 (about 69% and 51%, respectively).
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Description (incidence and severity):
Food consumption of the high-dose F0 females (1000 mg/kg bw/d) was statistically significantly below the concurrent control values during GD 7 - 14 and GD 0 - 20 (about 8%, respectively). This was assessed as treatment related. The food consumption of the high-dose F0 females (1000 mg/kg bw/d) during the premating and lactation period, as well as the food consumption of all test substance-treated F0 male animals (100, 300 and 1000 mg/kg bw/d) and the mid- and low-dose F0 females was comparable to the concurrent control values throughout the entire study period.
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
not examined
Haematological findings:
effects observed, treatment-related
Description (incidence and severity):
At the end of the administration period in females of test groups 1 and 3 (100 and 1000 mg/kg bw/d), platelet counts were lower compared to controls. In test group 1 the mean was not dose-dependently altered and therefore the change was incidental and not treatmentrelated. In test group 3 the median platelet count was higher compared to test group 1, but the mean was lower. Mean and median platelet counts in females of test group 3 (1000 mg/kg b w/d) were below the historical control range. Therefore, this decrease has to be regarded as adverse.
Clinical biochemistry findings:
effects observed, non-treatment-related
Description (incidence and severity):
No treatment-related changes among clinical chemistry parameters were observed.
At the end of the administration period in males of test groups 1 and 2 (100 and 300 mg/kg bw/d), aspartate aminotransferase (AST) activities were lower compared to controls. In males of test groups 2 and 3 (300 and 1000 mg/kg bw/d) glucose levels were increased and in females of test group 2 (300 mg/kg bw/d) urea levels were decreased. All mentioned parameters were not dose-dependently changed and therefore the alterations were regarded as incidental and not treatment-related.
Urinalysis findings:
effects observed, non-treatment-related
Description (incidence and severity):
No treatment-related changes among urinalysis parameters were observed.
In females of test group 2 (300 mg/kg bw/d) urine volume was decreased and urine specific gravity was increased (not statistically significantly). These alterations were not dosedependent and therefore they were regarded as incidental and not treatment-related.
Behaviour (functional findings):
effects observed, non-treatment-related
Description (incidence and severity):
No test substance-related or spontaneous findings were observed in male and female animals of all test groups during the home cage observation. The open field observations did not reveal any test substance-related findings in male and female animals of all test groups. There were no test substance-related findings in male and female animals of all test groups. No test substance-related impaired parameters were observed in male and female animals of all test groups. Comparing single intervals of treated animals with the control group, no significant deviations were measured during motor activity merasurement with the exception of the decreased mean value at interval 2 in male animals of test group 3 (1000 mg/kg bw/d). As the overall motor activity measurement in male animals of test group 3 (1000 mg/kg bw/d) was not statistically significant impaired and in females in the comparable intervals increased values (without statistical significance) were seen, the change was assessed as being spontaneous and not related to treatment.
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
effects observed, non-treatment-related
Histopathological findings: non-neoplastic:
effects observed, non-treatment-related
Description (incidence and severity):
All findings occurred either individually or were biologically equally distributed over control and treatment groups. They were considered to be incidental or spontaneous in origin and without any relation to treatment.
Histopathological findings: neoplastic:
not examined

Reproductive function / performance (P0)

Reproductive performance:
effects observed, non-treatment-related
Description (incidence and severity):
For nearly all F0 parental males, which were placed with females to generate F1 pups, copulation was confirmed. Copulation was not confirmed for high-dose male No. 37 paired with high-dose female No. 137. Thus, the male mating index was 100% in the control, low- and mid-dose group and 90% in the high-dose group. Fertility was proven for most of the F0 parental males within the scheduled mating interval for F1 litter. One high-dose male (1000 mg/kg bw/d - No. 37) and one mid-dose male (300 mg/kg bw/d -No. 29) did not generate pregnancy. Thus, the male fertility index ranged between 90% and 100% without showing any relation to dosing. This reflects the normal range of biological variation inherent in the strain of rats used for this study. The apparently infertile male rats did not show relevant gross lesions.
The female mating index calculated after the mating period for F1 litter was 100% in test groups 0 - 2 and 90% in test group 3. The mean duration until sperm was detected (GD 0) varied between 2.2 and 3.6 days without any relation to dosing. All female rats delivered pups or had implants in utero with the following exceptions:
• High-dose female No. 137 (mated with male No. 37) did not become pregnant.
• Mid-dose female No. 129 (mated with male No. 29) did not become pregnant.
The fertility index varied between 90% in test group 2 and 100% in test groups 0 - 1 and 3. These values reflect the normal range of biological variation inherent in the strain of rats used for this study. None of the non-pregnant females had any relevant gross lesions. The mean duration of gestation was similar in all test groups (i.e. between 21.9 and 22.2 days). The gestation index was 100% in test groups 0 - 1 and 3 and 88.9% in test group 2. These
values reflect the normal range of biological variation inherent in the strain of rats used for this study. Implantation was not affected by the treatment since the mean number of implantation sites was comparable between all test substance-treated groups and the control, taking normal biological variation into account (11.9 / 11.7 / 10.3 and 12.6 implants/dam in test groups 0-3, respectively). Furthermore, there were no indications for any test substance-induced intrauterine embryo-/fetolethality since the post-implantation loss did not show any statistically significant differences between the groups, and the mean number of F1 pups delivered per dam remained unaffected (11.6 / 11.3 / 10.5 and 12.0 pups/dam in test groups 0 - 3, respectively).
One sperm negative mid-dose female (300 mg/kg bw/d - No. 130) did not deliver pups but show one implantation site at necropsy. Due to this single animal with 100% post implantation loss the mean value for post implantation loss in the mid dose (19,1%) was outside the historical control range (0,7 – 18,3 %). This deviation was assessed as incidental and not treatment-related. The rate of liveborn pups was also not affected by the test substance, as indicated by live birth indices of 100% / 99.1% / 100% and 99.1% in test groups 0 - 3, respectively. Moreover, the number of stillborn pups was not significantly different between the test groups. All values are well covered by the historical control range. Thus, the test substance did not adversely affect reproduction and delivery of the F0 generation parental females.

Effect levels (P0)

open allclose all
Dose descriptor:
NOAEL
Remarks:
general, systemic toxicity
Effect level:
300 mg/kg bw (total dose)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: Based on decreased food consumption and decreased body weight parameters as well as clinical chemistry changes at 1000 mg/kg bw/d.
Dose descriptor:
NOAEL
Remarks:
reproductive performance and fertility
Effect level:
1 000 mg/kg bw (total dose)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no toxicity observed

Results: F1 generation

General toxicity (F1)

Clinical signs:
no effects observed
Description (incidence and severity):
There were no test substance-related adverse clinical signs observed in any of the F1 generation pups of the different test groups.
Dermal irritation (if dermal study):
not examined
Mortality / viability:
mortality observed, non-treatment-related
Description (incidence and severity):
The viability index indicating pup mortality during lactation (PND 0 - 4) varied between 99.3%/ 100% /100.0% and 99.2% in test groups 0 - 3, respectively, without showing any association to treatment.
The mean number of delivered F1 pups per dam and the rates of liveborn, stillborn, cannibalized and dead F1 pups were evenly distributed among the test groups. The respective values reflect the normal range of biological variation inherent in the strain used in this study, as they are in the historical control range.
The pup mortality based on total number of stillborn pups, dead pups, pups sacrificed moribund and cannibalized pups varied between 1 / 1 / 0 and 2 in test groups 0 - 3, respectively, without test substance-related influence.
The sex distribution and sex ratios of live F1 pups on the day of birth and PND 4 did not show substantial differences between the control and the test substance-treated groups; slight differences were regarded to be spontaneous in nature.
Body weight and weight changes:
effects observed, non-treatment-related
Description (incidence and severity):
No test substance-related influence on body weights and body weight change values of F1 pups were noted in in any test group (100, 300 and 1000 mg/kg bw/d). Five male and seven female runts were seen in test group 1, two female runts were seen in test group 2 and one male runt was seen in the test group 3.
Gross pathological findings:
no effects observed
Description (incidence and severity):
There were no test substance-related adverse necropsy observations in any of the F1 generation pups of the different test groups.

Effect levels (F1)

Dose descriptor:
NOAEL
Remarks:
developmental toxicity
Generation:
F1
Effect level:
1 000 mg/kg bw (total dose)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: no toxicity observed

Overall reproductive toxicity

Reproductive effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
Under the conditions of the present OECD 422 combined repeated dose toxicity study with the reproductive/developmental screening test in Wistar rats, the NOAEL (no observed adverse effect level) for general, systemic toxicity of Etocrilene was 300 mg/kg bw/d based on decreased food consumption and decreased body weight parameters as well as clinical chemistry changes at 1000 mg/kg bw/d. The NOAEL for reproductive performance and fertility was 1000 mg/kg bw/d for the F0 parental rats. The NOAEL for developmental toxicity in the F1 offspring was 1000 mg/kg bw/d, the highest tested dose.
Executive summary:

The test article was administered daily as an aqueous preparation to groups of 10 male and 10 female Wistar rats (F0 animals) by gavage at doses of 100, 300 and 1000 mg/kg body weight/day (mg/kg bw/d). Control animals (10 male and 10 female Wistar rats) were dosed daily with the vehicle only (1% Carboxymethylcellulose suspension in drinking water). The duration of treatment covered a 2-week pre-mating and a mating period in both sexes, approximately 4 days post-mating in males, and the entire gestation period as well as approximately 4 weeks of the lactation period. After 2 weeks of premating treatment the F0 animals were mated to produce F1 generation pups. Mating pairs were from the same test group. Mating was discontinued as soon as sperm were detected in the vaginal smear. F0 animals were examined for their reproductive performance including determination of the number of implantation sites and the calculation of postimplantation loss for all F0 females. A detailed clinical observation (DCO) was performed in all animals before initial test substance administration and, as a rule, thereafter at weekly intervals. Food consumption of the F0 parents was determined once weekly during premating. In dams food consumption was determined for gestation days 0 - 7, 7 - 14, 14 - 20 and lactation days 1 - 4. Body weights of F0 parents were determined once a week, in males throughout the study

and in females during premating. During gestation and lactation period, F0 females were weighed on gestation days (GD) 0, 7, 14 and 20, on the day of parturition (postnatal day [PND] 0) and on PND 4. The pups were sexed and examined for macroscopically evident changes on PND 0. They were weighed on PND 1 and on PND 4. Their viability was recorded. At necropsy on PND 4,

all pups were sacrificed with CO2, under isoflurane anesthesia, and examined macroscopically for external and visceral findings.

Clinico-chemical and hematological examinations as well as urinalyses were performed in 5 animals per sex and group towards the end of the administration period. At the end of the administration period a functional observational battery was performed and

motor activity was measured in 5 parental males and females per group. All F0 parental animals were sacrificed by decapitation, under isoflurane anesthesia, and were assessed by gross pathology. Weights of selected organs were recorded and a histopathological examination was performed. Parental animals of the high dose group (1000 mg/kg bw/d) showed slightly decreased food consumption in the females during gestation (up to about 8% below control). In addition, decreased body weights was recorded in the females on premating day 13 (about 4% below control), during GD 7 - 14 (up to 6% below control) and on PND 4 (about 6% below control). Decreased body weight change in the males and females during premating (up to 29% and 69% below control, respectively were also recorded. Furthermore, decreased platelet counts in females was evident and significantly decreased terminal body weight in males (about 6% below control). No test substance related findings were noted in parental animals of the mid and low dose group and in all F1 animals.

Under the conditions of the present OECD 422 combined repeated dose toxicity study with the reproductive/developmental screening test in Wistar rats, the NOAEL (no observed adverse effect level) for general, systemic toxicity of Etocrilene was 300 mg/kg bw/d based on decreased food consumption and decreased body weight parameters as well as clinical chemistry changes at 1000 mg/kg bw/d. The NOAEL for reproductive performance and fertility was 1000 mg/kg bw/d for the F0 parental rats. The NOAEL for developmental toxicity in the F1 offspring was 1000 mg/kg bw/d, the highest tested dose.