3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, oligomers, 2-Hydroxy-1(2)- methylethyl carbamate blocked

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

NOAEL = 1200 mg/kg bw/d

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Apr-Jul 18

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

GLP compliance:

yes

Limit test:

yes

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Expiration date of the lot/batch:
23-05-2019

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
Room temperature
- Stability under test conditions: stable

FORM AS APPLIED IN THE TEST (if different from that of starting material)
- Test substance preparations in corn oil

Species:

rat

Strain:

Wistar

Details on species / strain selection:

Wistar Rat; Crl:WI(Han)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:
Charles River Laboraories, Research Models and Services, Germany GmbH
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: about 11-12 weeks (male animals), about 10 weeks (female animals)
- Housing:
During pre-treatment: Polysulfonate cages Typ 2000P (H-Temp), floor area about 2065 cm2 (610 x 435 x 215 mm); supplied by TECHNIPLAST, Hohenpeißenberg, Germany
During pre-mating, mating, gestation, lactation, males after mating and females after weaning: Polycarbonate cages type III
- Diet (e.g. ad libitum):
ad libitum
- Water (e.g. ad libitum): ad libitum

ENVIRONMENTAL CONDITIONS
- Temperature (°C):
20-24°C
- Humidity (%):45-65%
- Air changes (per hr):
15
- Photoperiod (hrs dark / hrs light):
12h/12h

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

The test substance was applied as suspension.

Details on mating procedure:

In general, each of the male and female animals was mated overnight in a 1:1 ratio for a maximum of 2 weeks. Throughout the mating period, each female animal was paired with a predetermined male animal from the same test group.
The animals were paired by placing the female in the cage of the male mating partner from about 16.00 h until 06.30 - 09.00 h of the following morning. Deviations from the specified times were possible on weekends and public holidays and were reported in the raw data. A vaginal smear was prepared after each mating and examined for the presence of sperm. If sperm was detected, pairing of the animals was discontinued. The day on which sperm was detected was denoted gestation day (GD) 0 and the following day "GD 1".
Females that were successfully mated in the first night were directly transferred from study phase “mating” into study phase “gestation” before performing clinical observations. Therefore, the tables clinical observation of females in study phase “mating” show less examined animals than the nominal sample size of 10 females. The clinical observations of successfully mated females were documented in study phase “gestation”.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

The analytical verification of the test substance preparations were carried out as separate study at the test faciclity Competence Center Analytics of BASF SE. The study was carried out in compliance with GLP. The stability of the test substance in corn oil over a period of 7 days at room temperature was proven (Project No. 17L00369).

Duration of treatment / exposure:

The duration of treatment covered a 2-week premating period and mating period in both sexes, one day post-mating in males, and the entire gestation and lactation period in females up to one day prior to the day of schedule sacrifice of the animals.

Frequency of treatment:

once daily

Details on study schedule:

N/A

Dose / conc.:

120 mg/kg bw (total dose)

Dose / conc.:

400 mg/kg bw (total dose)

Dose / conc.:

1 200 mg/kg bw (total dose)

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose level selection was based on a 14-day range-finding study (10C0437/16C137).

Positive control:

N/A

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule:
conducted at least once daily for any signs of morbidity, pertinent behavioral changes and/or signs of overt toxicity. All animals were checked daily for any abnormal clinical signs before the administration as well as within 2 hours and within 5 hours after the administration.

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: Detailed clinical observations were performed in all animals prior to the administration period and thereafter at weekly intervals.

BODY WEIGHT: Yes
- Time schedule for examinations:
Body weight of male and female parental animals was determined before the start of the administration period in order to randomize the animals. During the administration period body weight was determied on study day 0 and thereafter once a week at the same time of the day (in the morning).

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- food consumption was determined once a week for male and female parental animals.

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

OPHTHALMOSCOPIC EXAMINATION: Not specified

HAEMATOLOGY: Yes
- Time schedule for collection of blood:
In the morning, blood was taken from the retro-bulbar vanous plexus from fasted animals.
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes
- How many animals:
5 surviving parental males per group at termination and in 5 females with litters per group at PND 14.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood:
In the morning, blood was taken from the retro-bulbar vanous plexus from fasted animals.
- Animals fasted: Yes
- How many animals:
5 surviving parental males per group at termination and in 5 females with litters per group at PND 14.

URINALYSIS: Not specified

IMMUNOLOGY: Not specified

OTHER:
- A functional observational battery was performed in the first five parental male animals per test group and the first surviving females with litter of all test groups at the end of the administration period. The FOB started with passive observations without disturbing the animals, followed by removal from the home cage, open field observations in a standard arena and sensorimotor tests as well as reflex tests.
- Motor activity (MA) was also measured from 14 pm onwards on the same day as the FOB was performed in the first five parental males and the first five surviving females with litter per group.
- Thyroid hormones: blood samples were taken from all surplus pups per litter at PND 4 as well as one male and one female pup per litter at PND14 by decapitation under isoflurane anesthesia. Additionally blodd samples from all dams at PND 14 and all males at termination were taken by puncturing the retrobulbar venous plexus under isoflurane anesthesia. Blood samples from the adult males and the PND 13 pups were assessed for serum levels for thyroid hormones.

Oestrous cyclicity (parental animals):

- For all females of the pool estrous cycle normality was evaluated before the beginning of the administration. In all parental females, in the premating phase, estrous cycle length and normality was evaluated by preparing vaginal smears during a minimum of 2 weeks prior to premating, mating and throughout cohabitytion until there is evidence of sperm in the vaginal smear. Additionally, on the day of scheduled sacrifice, the estrous status was also determined in all F0 female animals.

Sperm parameters (parental animals):

Special attention was given to the stages of spermatogenesis and histopathology of interstitial testicular cell structure.

Litter observations:

Each litter was examined to determine the following, if practically possible:
- Pup number and status of delivery:
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.

- Mortality / Viability:
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. Dead pups were evaluated by the methods, which are described in detail in “Necropsy observations”. The number and percentage of dead pups on the day of birth (PND 0) and of pups dying between PND 1-4, 5-7 and 8-13 were determined. Pups, which died accidentally or had to be sacrificed due to maternal death, were not included in these calculations. The number of live pups/litter was calculated on the day of birth (PND 0), and on lactation days 4, 7 and 13. Furthermore, viability and survival indices were calculated according to the following formulas:

-Sex ratio:
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. Later, during the course of lactation, this initial sex determination was followed up by surveying the external appearance of the anogenital region and the mammary line. The sex of the pups was finally confirmed at necropsy. The sex ratio was calculated at PND 0 and PND 13.

- Clinical signs:
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.

- Body weights:
The pups were weighed on the day after birth (PND 1) as well as on PND 4 (before standardization), 7 and 13. Pups' body weight change was calculated from these results. The individual weights were always determined at about the same time of the day (in the morning). In the summary tables pup body weights and pup body weight change are listed for males, females and males + females. “Runts” were defined on the basis of the body weights on PND 1. "Runts" are pups that weigh less than 75% of the mean weight of the respective control pups.

- Necropsy pups:
On PND 4, as a result of standardization, the surplus pups or 2 preferably female pups per litter, respectively, was sacrificed under isoflurane anesthesia by decapitation. Blood was sampled for determination of thyroid hormone concentrations. After sacrifice, the pups were examined externally and eviscerated, and their organs were assessed macroscopically. On PND 13, one selected male and one female pup per litter was sacrificed under isoflurane anesthesia by decapitation. Blood was sampled for determination of thyroid hormone concentrations. Thyroid glands/parathyroid glands were fixed in neutral buffered 4% formaldehyde solution and was transferred to the Pathology Laboratory for possible further processing.
The remaining pups were sacrificed under isoflurane anesthesia with CO2. After sacrifice, all pups were examined externally and eviscerated, and their organs were assessed macroscopically. All stillborn pups and all pups that died before day 13 were examined externally, eviscerated and 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-bycase basis, depending on the type of finding noted. Pups surviving to planned termination were killed by decapitation on Days 5-6 of lactation.

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.
The following weights were determined in all animals sacrificed on schedule:
1. Anesthetized animals (final body weight)
2. Epididymides
3. Ovaries
4. Prostate (ventral and dorsolateral part together, fixed)
5. Seminal vesicles with coagulating glands (fixed)
6. Testes
7. Thyroid glands (with parathyroid glands) (fixed)
8. Uterus (with cervix)
The following weights were determined in 5 animals per sex/test group sacrificed on
schedule (females with litters only, same animals as used for clinical pathological
examinations):
1. Adrenal glands (fixed)
2. Brain
3. Heart
4. Kidneys
5. Liver
6. Spleen
7. Thymus (fixed)
All paired organs were weighed together (left and right).

The following organs or tissues of all parental animals were fixed in in 4% neutral-buffered
formaldehyde or in modified Davidson’s solution:
1. All gross lesions
2. Adrenal glands
3. Aorta
4. Bone marrow (femur)
5. Brain
6. Cecum
7. Cervix
8. Coagulating glands
9. Colon
10. Duodenum
11. Epididymides (modified Davidson’s solution)
12. Esophagus
13. Extraorbital lacrimal glands
14. Eyes with optic nerve (modified Davidson’s solution)
15. Femur with knee joint
16. Heart
17. Ileum
18. Jejunum (with Peyer’s patches)
19. Kidneys
20. Larynx
21. Liver
22. Lungs
23. Lymph nodes (axillary and mesenteric)
24. Mammary gland (male and female)
25. Nose (nasal cavity)
26. Ovaries (modified Davidson’s solution)
27. Oviducts
28. Pancreas
29. Parathyroid glands
30. Pharynx
31. Pituitary gland
32. Prostate gland
33. Rectum
34. Salivary glands (mandibular and sublingual)
35. Sciatic nerve
36. Seminal vesicles
37. Skeletal muscle
38. Spinal cord (cervical, thoracic and lumbar cord)
39. Spleen
40. Sternum with marrow
41. Stomach (forestomach and glandular stomach)
42. Testes (modified Davidson’s solution)
43. Thymus
44. Thyroid glands
45. Trachea
46. Urinary bladder
47. Uterus
48. Vagina

The uteri of all cohabited female F0 parental animals were examined for the presence and number of implantation sites. The uteri of apparently nonpregnant animals or empty uterus horns were placed in 1% ammonium sulfide solutions for about 5 minutes in order to be able to identify early resorptions or implantations (SALEWSKI E (1964)). Then the uteri were rinsed carefully in physiologic salt solution (0.9 % NaCl). When the examinations were completed, the uteri were transferred to the Pathology Laboratory for further processing.

Pups
On PND 13, one selected male and one female pup per litter was sacrificed under isoflurane anesthesia by decapitation. Blood was sampled for determination of thyroid hormone concentrations. Thyroid glands/parathyroid glands were fixed in neutral buffered 4% formaldehyde solution and were transferred to the Pathology Laboratory for possible further processing.

HISTOPATHOLOGY: Yes
Fixation was followed by histotechnical processing and examination by light microscopy.
Special attention was given to the stages of spermatogenesis and histopathology of interstitial testicular cell structure. The organs were trimmed according to the “Revised guides for organ sampling and trimming in rats and mice” (Ruehl-Fehlert et al., 2003; Kittel et al., 2004; Morawietz et al., 2004). A correlation between gross lesions and histopathological findings was attempted. Whenever in the ovary the diagnosis: „no abnormalities detected” was used that implies that all different stages of functional bodies (especially corpora lutea) were present and normal.

Postmortem examinations (offspring):

Necropsy pups
On PND 13, one selected male and one female pup per litter was sacrificed under isoflurane anesthesia by decapitation. Blood was sampled for determination of thyroid hormone concentrations. Thyroid glands/parathyroid glands were fixed in neutral buffered 4% formaldehyde solution and were transferred to the Pathology Laboratory for possible further processing (see 3.8.3.)

All pups were sexed and descriptions of all external abnormalities were recorded. The stomach was examined for the presence of milk. If possible, defects or cause of death were evaluated.

Statistics:

Means, medians, standard deviations and deviation vs control of each test group were calculated for several parameters.
For parameters with bidirectional changes: Non-parametric one-way analysis using KRUSKAL-WALLIS test. If the resulting p-value was equal or less than 0.05, a pairwise comparison of each dose group with the control group was performed using WILCOXON-test (twosided) for the hypothesis of equal medians.
For parameters with unidirectional changes: Pairwise comparison of each dose group with the control group using the WILCOXON-test (one-sided) for the hypothesis of equal medians
Throughout the chapter "results", the term "significant" implies that the inter-group differences have attained statistical significance (p 􀂔 0.05) when compared with the control group.

Reproductive indices:

For each group, the following calculations were performed:
Mating index (%), Fertility index (%), Gestation index (%),live birth index, post implantation loss (%)

Offspring viability indices:

Pup number, status at delivery, pup viability/mortality, viability index, survival index, sex ratio

Clinical signs:

no effects observed

Dermal irritation (if dermal study):

not examined

Mortality:

no mortality observed

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

No test substance-related alterations of mean body weights were observed for male and female animals of test groups 1-3 (120, 400 and 1200 mg/kg bw/d) when compared to the control group.
The body weight change of test group 3 (1200 mg/mg bw/d) was significantly increased during gestation days 7-14. This isolated increase of body weight change in females at one time point was assessed not related to treatment. It is more likely to be related to the larger mean litter size of 13.6 pubs delivered per dam observed in this test group in comparison to control 11.3 pubs delivered per dam.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Food consumption was significantly increased in males of test group 3 (1200 mg/kg bw/d; 10.3%) on study day 7 during premating as well as in males of test group 3 between study days 0-13 (9.1%). It could not be excluded that this increases of food consumption was treatment-related, however, this alteration was assessed as non-adverse.
Food consumption of the F0 females of test group 3 (1200 mg/kg bw/d) as well as males and females in dose groups 1 and 2 (120 and 400 mg/kg bw/d) was not influenced by the treatment throughout the entire study period.

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

no effects observed

Ophthalmological findings:

not specified

Haematological findings:

no effects observed

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 rats of both sexes of test group 2 (400 mg/kg bw/d) and in females of test group 1 (120 mg/kg bw/d) globulin values were significantly increased.
Additionally, in females of test group 2, total protein and albumin values were significantly higher compared to controls. All changes were not dose-dependent and therefore they were regarded as incidental and not treatment-related.

Urinalysis findings:

not specified

Behaviour (functional findings):

effects observed, non-treatment-related

Description (incidence and severity):

Deviations from "zero values" were obtained in several rats. However, as most findings were equally distributed between test-substance treated groups and controls, without a doseresponse relationship or occurred in single animals only, these observations were considered as incidental.
The following examinations were performed during FOB and are assessed individually:
- Home cage observations: No test substance-related effects were observed.
- Open field observations: No test substance-related effects were observed.
- Sensorimotor tests/reflexes: No test substance-related effects were observed.
- Quantitative Parameters: No test substance-related effects were observed.
Regarding the overall motor activity as well as the individual intervals of observations, no test substance-related deviations were noted for male and female animals.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

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.
The stages of spermatogenesis in the testes of males of the high dose test group were comparable to those of the controls. In high dose females the different stages of functional bodies in the ovaries were present and comparable to the control animals.
The female animal (No. 101), which was not pregnant as well as the male mating partner (No. 001) did not show relevant histopathological findings.

Histopathological findings: neoplastic:

no effects observed

Other effects:

no effects observed

Description (incidence and severity):

Estrous cycle data revealed regular cycles in the rearing F1 females of all test groups including the control. The mean estrous cycle duration in the different test groups (0-3) ranged from 3.9 to 4.0 days.

Reproductive function: oestrous cycle:

no effects observed

Description (incidence and severity):

Estrous cycle data revealed regular cycles in the rearing F1 females of all test groups including the control. The mean estrous cycle duration in the different test groups (0-3) ranged from 3.9 to 4.0 days.

Reproductive function: sperm measures:

no effects observed

Description (incidence and severity):

The spermatogenic staging profiles were normal for all males.

Reproductive performance:

no effects observed

Description (incidence and severity):

No toxicologically relevant effects on reproductive parameters were noted.

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS)
No mortality occurred during the study period. No clinical signs of toxicity were noted during the observation period.
BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS)
No test substance-related alterations of mean body weights were observed for male and female animals of test groups 1-3 (120, 400 and 1200 mg/kg bw/d) when compared to the control group.
The body weight change of test group 3 (1200 mg/mg bw/d) was significantly increased during gestation days 7-14. This isolated increase of body weight change in females at one time point was assessed not related to treatment. It is more likely to be related to the larger mean litter size of 13.6 pubs delivered per dam observed in this test group in comparison to control 11.3 pubs delivered per dam.

Absolute body weights were significantly lower on Day 1 of the mating period and Day 4 of the lactation period for females at 300 and 100 mg/kg bw/day, respectively. In the absence of a treatment related distribution, this was not considered to be toxicologically relevant.

No toxicologically relevant changes in food consumption before or after allowance for body weight were noted.

Absolute food consumption was significantly lower for females at 100 mg/kg bw/day on Days 11-14 of the post coitum period and Days 1-4 of the lactation period. Food consumption was also significantly lower for females at 300 mg/kg bw/day on Days 17-20 of the post coitum period. As the difference from controls was only slight and occurred in the absence of a treatment related distribution, it was not considered toxicologically relevant.

REPRODUCTIVE FUNCTION: SPERM MEASURES (PARENTAL ANIMALS)
The spermatogenic staging profiles were normal for all Group 1 and 4 males, and for all males suspected to be infertile.

REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS)
No toxicologically relevant effects on reproductive parameters were noted. There were 10, 9, 10 and 10 pregnant females in the control and 100, 300 and 1000 mg/kg bw/day groups, respectively.

The mating, fertility and conception indices, precoital time, and number of corpora lutea and implantation sites were unaffected by treatment.

ORGAN WEIGHTS (PARENTAL ANIMALS)
No toxicologically relevant changes were noted in organ weights and organ to body weight ratios.

Relative liver weights were significantly lower for males at 1000 mg/kg bw/day. This was not toxicologically relevant as an increase in liver to body weight ratios would be expected if treatment related toxicity was evident. Similarly, the significantly lower terminal body weight seen for females at 100 mg/kg bw/day was not considered toxicologically relevant.

GROSS PATHOLOGY (PARENTAL ANIMALS)
Macroscopic observations at necropsy did not reveal any alterations that were attributable to treatment.

All macroscopic findings noted were incidental in nature. These included pelvic dilation of the kidneys, tan, red-brown or reddish discoloration of the thymus and mandibular lymph node, reduced size of the left prostate, several tan foci on the right clitoral gland, thickened limiting ridge of the stomach, enlarged spleen, mesenteric lymph node and/or liver, cloudy left eye, yellowish, hard nodule on the uterine adipose tissue, scab on the back of the neck and alopecia on the throat, flank, or foreleg. These findings remained within the range of findings encountered among rats of this age and strain, and none were attributable to treatment. None of these were considered to be toxicologically relevant.

HISTOPATHOLOGY (PARENTAL ANIMALS:
There were no treatment-related microscopic findings. All recorded microscopic findings were within the normal range of background alterations encountered in Wistar (Han) rats of this age and strain.

No abnormalities were seen in the reproductive organs of the rats who failed to sire or deliver healthy pups, which could account for their infertility.

Furthermore, the spermatogenic staging profiles were normal for all Group 1 and 4 males, and for all males suspected to be infertile.

Dose descriptor:

NOAEL

Remarks:

parental, reproduction and developmental

Effect level:

1 200 mg/kg bw (total dose)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects in highest tested dose (limit dose)

Clinical signs:

no effects observed

Description (incidence and severity):

The surviving F1 pups of test groups 0-3 did not show adverse clinical signs up to scheduled sacrifice on PND 4, resp. PND 13.

Dermal irritation (if dermal study):

not examined

Mortality / viability:

no mortality observed

Description (incidence and severity):

The viability index indicating pup mortality during PND 0-4 varied between 100% in test group 0 (control) and test group 1 (120 mg/kg bw/d), 98.0% in test group 2 (400 mg/kg bw/d) and 99.1% in test group 3 (1200 mg/kg bw/d). These values reflected the normal range of biological variation inherent in the strain of rats used for this study as all respective values were within the range of the historical control data (see PART III, Supplement). The survival index indicating pup mortality on PND 4 – 13 was 100% in all test groups.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Mean body weight and body weight changes of pups in all test groups were comparable to the control group with one exception. Mean body weights of females (-9.7%) in test group 2 (400 mg/kg bw/d) were significantly decreased on PND 7. This isolated finding with not dose dependency was assessed as incidental and not treatment-related.
On PND 1, two male and 4 female runts were seen in test group 1 (120 mg/kg bw/d), four male and 2 female runts were seen in test group 2 (400 mg/kg bw/d), as well as two male and one female runts were seen in test group 3 (1200 mg/kg bw/d).
All values were within the range of the biological variation inherent in the strain of rats used for this study.

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Anogenital distance (AGD):

effects observed, non-treatment-related

Description (incidence and severity):

Anogenital index was significantly increased in female pups of test group 3 (1200 mg/kg bw/d). This determined anogenital indices was still in the range of historical control data (anogenital index: 0.72 – 0.87) and therefore regarded as incidental and not related to treatment.

Nipple retention in male pups:

no effects observed

Description (incidence and severity):

The apparent number and percentage of male pups having nipple/areolae was not influenced by the test substance when examined on PND 13.

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

A few F1 pups showed spontaneous findings at gross necropsy, such as empty stomach, post mortem autolysis, dilated renal pelvis and hydronephrosis. These findings occurred without any relation to dosing or were observed in a single pup only
and considered to be spontaneous in nature. All other F1 pups of any test groups (0-3) did not show adverse findings during necropsy.

Histopathological findings:

not examined

Other effects:

not specified

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

VIABILITY (OFFSPRING)
The viability index indicating pup mortality during PND 0-4 varied between 100% in test group 0 (control) and test group 1 (120 mg/kg bw/d), 98.0% in test group 2 (400 mg/kg bw/d) and 99.1% in test group 3 (1200 mg/kg bw/d). These values reflected the normal range of biological variation inherent in the strain of rats used for this study as all respective values were within the range of the historical control data. The survival index indicating pup mortality on PND 4 – 13 was 100% in all test groups..

CLINICAL SIGNS (OFFSPRING)
The surviving F1 pups of test groups 0-3 did not show adverse clinical signs up to scheduled sacrifice on PND 4, resp. PND 13.

BODY WEIGHT (OFFSPRING)
Mean body weight and body weight changes of pups in all test groups were comparable to the control group with one exception. Mean body weights of females (-9.7%) in test group 2 (400 mg/kg bw/d) were significantly decreased on PND 7. This isolated finding with not dose dependency was assessed as incidental and not treatment-related. On PND 1, two male and 4 female runts were seen in test group 1 (120 mg/kg bw/d), four male and 2 female runts were seen in test group 2 (400 mg/kg bw/d), as well as two male and one female runts were seen in test group 3 (1200 mg/kg bw/d). All values were within the range of the biological variation inherent in the strain of rats used for this study.

GROSS PATHOLOGY (OFFSPRING)
A few F1 pups showed spontaneous findings at gross necropsy, such as empty stomach, post mortem autolysis, dilated renal pelvis and hydronephrosis.
These findings occurred without any relation to dosing or were observed in a single pup only and considered to be spontaneous in nature.
All other F1 pups of any test groups (0-3) did not show adverse findings during necropsy.

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 1 200 mg/kg bw (total dose)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effect in highest tested dose group (limit dose)

Reproductive effects observed:

no

Developmental data

 

Gestation

The gestation index was unaffected by treatment up to 1200 mg/kg bw/day.

 

Conclusions:

Based on the results of this study, a parental, reproduction and developmental No Observed Adverse Effect Level (NOAEL) of at least 1200 mg/kg bw/day was determined.

Executive summary:

A combined 28-day repeated dose toxicity study with the reproduction/developmental toxicity screening test of the test item was conducted in rats by oral gavage according to OECD 422 guideline and GLP (WIL Research Europe, 2013).

The test item was administered orally by gavage to groups of 10 male and 10 female Wistar rats (F0 animals) at dose levels of 0 (test group 0, vehicle control), 120 (test group 1), 400 (test group 2) and 1200 mg/kg bw/d (test group 3). The content of the main test compound is 83.9 %, corresponding to 3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, oligomers, reaction products with 1,2-propanediol, monocarbamate.

The duration of treatment covered a 2 weeks pre-mating period, 2 weeks mating period in both sexes, approximately 7 days post-mating in males, the entire gestation period as well as up to 13 days of the lactation period in females, and up to one day prior to the day of schedule sacrifice of the animals

 

Analyses confirmed the overall accuracy of the prepared concentrations and the homogeneity of the test substance in the vehicle. The stability of these preparations was demonstrated over a period of 7 days under ambient conditions.

Regarding clinical examinations including determination of food consumption and body weight parameters, during pre-mating and mating in males and females of all test groups as well as during gestation and lactation in females no treatment-related findings were observed. In the subsequent investigations including the detailed clinical observation (DCO), the functional observational battery (FOB) and measurement of motor activity (MA) no treatment related, adverse differences to control were observed at any dose level. Concerning clinical pathology, no treatment-related, adverse effects were observed up to a dose of the test substance of 1200 mg/kg bw/d. Regarding pathology, there were no treatment-related organ weight changes, gross lesions, and histopathological findings in male and female Wistar rats. 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. The fertility and reproductive performance were not impaired in male or female parental animals of all test groups (120, 400, and 1200 mg/kg bw/d).

Regarding developmental toxicity, no adverse effects were observed up to the highest dose tested 1200 mg/kg bw/d.

Based on these results, a parental, reproduction and developmental No Observed Adverse Effect Level (NOAEL) of at least 1200 mg/kg bw/day was determined.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

A combined 28-day repeated dose toxicity study with the reproduction/developmental toxicity screening test of the registered substance was conducted in rats by oral gavage according to OECD 422 guideline and GLP (BASF SE, 2019).

Based on the results of the 14-Day dose range finding study, the dose levels for this combined 28-day oral gavage study with reproduction/developmental toxicity screening test were 120, 400 and 1200 mg/kg bw/day.

The test substance was administered daily by gavage as a suspension to groups of 10 male and 10 female Wistar rats (F0 animals) at doses of 0, 120, 400 and 1200 mg/kg body weight/day (mg/kg bw/d). The content of the main test compound is 83.9 %, corresponding to 3 -Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate, oligomers, reaction products with 1,2-propanediol, monocarbamate. Therefore, the dose levels of the test substance correspond to the administration of 0, 101, 336, and 1007 mg/kg bw/d of the four main components. Control animals were dosed daily with the vehicle only (corn oil Ph.Eur.8.0).

The duration of treatment covered a 2-week premating period and mating period in both sexes, (mating pairs were from the same dose group), one day post-mating in males, and the entire gestation and lactation period in females up to one day prior to the day of schedule sacrifice of the animals.

Under the conditions of this Combined Repeated Dose Toxicity Study with the Reproduction/Developmental Toxicity Screening Test, the oral administration by gavage of the test item to Wistar rats revealed no adverse findings in parental animals and progeny up to 1200 mg/kg bw/d corresponding to 1007 mg/kg bw/d of 3-Isocyanatomethyl-3,5,5 -trimethylcyclohexyl isocyanate, oligomers, reaction products with 1,2-Propanediol, monocarbamate.

Thus, the no observed adverse effect level (NOAEL) for general systemic toxicity, fertility and reproductive performance was 1200 mg/kg bw/d in both sexes of parental animals. The NOAEL for developmental toxicity in the F1 progeny was 1200 mg/kg bw/d.

Effects on developmental toxicity

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Justification for classification or non-classification

Based on the available data, the test substance is not classified with regard to toxicity to reproduction according to Directive 67/548/EEC (DSD) and Regulation (EC) No 1272/2008 (CLP), respectively.