1,2-Ethanediamine, N-{3-(trimethoxysilyl)propyl}-,N-{(ethenylphenyl)methyl}derivate,hydrochlorides

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

Screening study for reproductive/developmental toxicity (OECD 422, oral, rat): NOAEL reproductive toxicity = 100 mg/kg bw/day

Link to relevant study records

Reference

Endpoint:

screening for reproductive / developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-04-11 to 2018-03-18

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)

Version / remarks:

July 2016

Deviations:

no

GLP compliance:

yes

Limit test:

no

Species:

rat

Strain:

other: Crl:WI(Han) (outbred, SPF-Quality)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Females nulliparous and non-pregnant: yes
- Age at study initiation: P 10 wks for males (supplementary males in groups 1 and 3: 12 weeks) 12 wks for females (supplementary females in groups 1 and 3: 14 weeks)
- Weight at study initiation: not reported
- Housing: Macrolon plastic cages
- Diet: pelleted rodent diet provided ad libitum
- Water: tap-water provided ad libitum
- Acclimation period: at least 5 days prior to start of pretest (females) or treatment (males)

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19-22
- Humidity (%): 43-69
- Air changes (per hr): at least 10 room air changes/hour
- Photoperiod (hrs dark / hrs light): 12-hour light/12-hour

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on exposure:

PREPARATION OF DOSING SOLUTIONS: On each morning of dosing, the required amount of test item was transferred into a container, flushed with nitrogen and stored at room temperature in the tightly closed container until use. This was done for Groups 2, 3 and 4 separately to minimize the time that the test item was exposed to oxygen in the air during dosing.

Details on mating procedure:

- M/F ratio per cage: 1:1 basis
- Length of cohabitation: a maximum of 14 days
- Proof of pregnancy: sperm in vaginal smear referred to as day 0 of pregnancy
- A maximum of 14 days was allowed for mating, after which females who had not shown evidence of mating were separated from their males.
- Further matings after two unsuccessful attempts: not reported
- After successful mating each pregnant female was caged individually in Macrolon plastic cages.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

A dose control system (DCS) was used as additional check to verify the dosing procedure according to Standard Operating Procedures.

Duration of treatment / exposure:

For Groups 0, 50 and 100 mg/kg bw/day, males were treated for 29 days, i.e. 2 weeks prior to mating, during mating, and up to the day prior to scheduled necropsy. Females that delivered were treated for 50-55 days, i.e. during 2 weeks prior to mating (with the objective of covering at least two complete estrous cycles), the variable time to conception, the duration of the pregnancy and at 13-15 days after delivery up to and including the day before scheduled necropsy. Females which failed to deliver healthy offspring were treated for 41 or 54 days.

For the highest dose group (200 mg/kg bw/day), treatment at the high dose was terminated after 10 days of dosing due to unacceptable high toxicity.

Frequency of treatment:

Once daily for 7 days per week, approximately the same time each day with a maximum of 6 hours difference between the earliest and latest dose.

Dose / conc.:

50 mg/kg bw/day (actual dose received)

Dose / conc.:

100 mg/kg bw/day (actual dose received)

Dose / conc.:

200 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

Group 1 (control group): 10 males and 10 females
Group 2 (50 mg/kg bw/day): 10 males and 10 females
Group 3 (100 mg/kg bw/day): 10 males and 12 females
Group 4 (200 mg/kg bw/day): 19 males and 19 females

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: Based on the results of a 14-day dose range finder in which dose limiting effects were noted from 300 mg/kg bw/day onward, the dose levels for this combined 28-day oral gavage study with reproduction/developmental toxicity screening test were selected to be 50, 100 and 200 mg/kg bw/day.
- Rationale for animal assignment: Before initiation of pretest (females) or treatment (males), by computer-generated random algorithm according to body weight, with all animals within ± 20% of the sex mean.

Positive control:

No

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: Once prior to start of treatment and at weekly intervals during the treatment period this was also performed outside the home cage in a standard arena

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: At least twice daily from start of treatment onwards up to the day prior to necropsy, detailed clinical observations were made for all animals, immediately after treatment and 1 hour thereafter (i.e. on the peak period of anticipated effects after treatment).

BODY WEIGHT: Yes
- Time schedule for examinations: Males and females were weighed on the first day of treatment (prior to first dosing) and weekly thereafter. Mated females were weighed on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum and during lactation on PND 1, 4, 7 and 13.

FOOD CONSUMPTION AND COMPOUND INTAKE:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes; weekly, except for males and females which were housed together for mating and for females without evidence of mating. Food consumption of mated females was measured on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum and during lactation on PND 1, 4, 7 and 13.
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): No

OTHER: The following functional observations tests were performed on each individual animal of the selected 5 animals/sex of Groups 1, 2 and 3 (note: Group 4 was euthanized preterm):

- hearing ability, pupillary reflex, and static righting reflex
- fore- and hind-limb grip strength, recorded as the mean of three measurements per animal
- locomotor activity; total movements and ambulations are reported. Ambulations represent movements characterized by a relocation of the entire body position like walking, whereas total movements represent all movements made by the animals, including ambulations but also smaller or finer movements like grooming, weaving or movements of the head.

The selected males were tested during Week 4 of treatment and the selected females were tested once during the last week of lactation (e.g. PND 6-13). These tests were performed in the morning prior to dosing.

Oestrous cyclicity (parental animals):

Except for supplementary females in Groups 1 and 3, daily vaginal lavage was performed to determine the stage of estrous beginning 14 days prior to treatment (pretest), the first 14 days of treatment and during mating until evidence of copulation was observed. Vaginal lavage continued for those females with no evidence of copulation until termination of the mating period.

For the supplementary females in Groups 1 and 3, daily vaginal lavage was performed to determine the stage of estrus beginning 14 days prior to treatment (pretest), the first 14 days of treatment with Elix water, the second 14 days of treatment with either Elix water (Group 1) or test item (Group 3), and during mating until evidence of copulation is observed.

On the day of scheduled necropsy, a vaginal lavage was taken from all females to determine the stage of estrous.

Sperm parameters (parental animals):

Parameters examined in P male parental generations: testis weight and epididymis weight. Slides of the testes (to examine staging of spermatogenesis) were stained with PAS/haematoxylin.

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- On PND 4 eight pups from each litter of equal sex distribution (if possible) were selected. Blood samples were collected from two of the surplus pups. Selective elimination of pups, e.g. based upon body weight, or anogenital distance was not done. Whenever the number of male or female pups prevented having four of each sex per litter, partial adjustment (for example, five males and three females) was acceptable.

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, weight gain, physical or behavioural abnormalities, anogenital distance (AGD), presence of nipples/areolae in male pups, and serum T4 levels

GROSS EXAMINATION OF DEAD PUPS:
Yes; At terminal sacrifice (PND 13-15), the thyroids from 1 male and 1 female pup per litter were preserved in 10% buffered formalin. If possible, these were the same pups as selected for blood sampling. The stomach of pups not surviving to the scheduled necropsy date was examined for the presence of milk, if possible. If possible, defects or cause of death were evaluated.

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: Following completion of the mating period (a minimum of 28 days of dose administration).
- Maternal animals: PND 14-16

GROSS NECROPSY
- Gross necropsy consisted of a full post mortem necropsy, with special attention being paid to the reproductive organs. Descriptions of all macroscopic abnormalities were recorded. The number of former implantation sites were recorded for all paired females. In case no macroscopically visible implantation sites were present, nongravid uteri were stained using the Salewski technique in order to detect any former implantation sites. From all animals (including animals that died spontaneously or were sacrificed in extremis), samples of the following tissues and organs shown in Table 1 were collected and fixed in 10% buffered formalin.

HISTOPATHOLOGY / ORGAN WEIGHTS
The tissues indicated in Table 2 were prepared for microscopic examination and weighed, respectively.

Postmortem examinations (offspring):

SACRIFICE
- Pups not selected during the culling process were sacrificed on PND 4. Pups, younger than 7 days were euthanized by decapitation. All remaining pups (PND 7-15) , except those used for blood sampling on PND 13-15, were sacrificed using Euthasol® 20% by intraperitoneal (ip) injection.

GROSS NECROPSY
- All pups were sexed by both external as well as internal examination. Descriptions of all abnormalities were recorded.


HISTOPATHOLOGY / ORGAN WEIGTHS
- At terminal sacrifice (PND 13-15), the thyroids from 1 male and 1 female pup per litter were preserved in 10% buffered formalin. If possible, these were the same pups as selected for blood sampling.

The stomach of pups not surviving to the scheduled necropsy date was examined for the presence of milk, if possible. If possible, defects or cause of death were evaluated.

Statistics:

The following statistical methods were used to analyse the data:

- If the variables could be assumed to follow a normal distribution, the Dunnett-test based on a pooled variance estimate was applied for the comparison of the treated groups and the control groups for each sex.
- The Steel-test was applied if the data could not be assumed to follow a normal distribution.
- The Fisher Exact-test was applied to frequency data.
- The Kruskal-Wallis nonparametric ANOVA test was applied to motor activity data to determine intergroup differences. In case intergroup differences were seen, the Wilcoxon test was applied to compare the treated groups to the control group.

All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance. Group means were calculated for continuous data and medians were calculated for discrete data (scores) in the summary tables. Test statistics were calculated on the basis of exact values for means and pooled variances. Individual values, means and standard deviations may have been rounded off before printing. Therefore, two groups may display the same printed means for a given parameter, yet display different test statistics values.

Reproductive indices:

Mating index (%) = (Number of females mated/Number of females paired) x 100
Fertility index (%) = (Number of pregnant females/Number of females mated) x 100
Gestation index (%) = (Number of females with living pups on Day 1/Number of pregnant females) x 100

Precoital time = Number of days between initiation of cohabitation and confirmation of mating
Duration of gestation = Number of days between confirmation of mating and the beginning of parturition

Offspring viability indices:

Post-implantation survival index (%) = (Total number of offspring born/Total number of uterine implantation sites) x 100
Live birth index (%) = (Number of live offspring on Day 1 after littering/Total number of offspring born) x 100
Percentage live males at First Litter Check (%) = Number of live male pups at First Litter Check/Number of live pups at First Litter Check) x 100
Percentage live females at First Litter Check (%) = (Number of live female pups at First Litter Check/Number of live pups at First Litter Check) x 100
Viability index (%) = (Number of live offspring on Day 4 before culling/Number live offspring on Day 1 after littering) x 100
Lactation index (%) = (Number of live offspring on Day 13 after littering/Number live offspring on Day 4 (after culling)) x 100

Group mean values were calculated from individual litter values.

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

Rales were noted at 200 mg/kg (in most males and several females, decedents included, on several days) and, less frequently, at 100 mg/kg (in two males and two females, decedents included, on one or two days) and 50 mg/kg (in one female on one day). Additionally, a few of the 200 mg/kg animals that were terminated after 10 treatment days showed gasping, laboured respiration, hunched posture and/or piloerection, mostly at the end of their treatment period and/or on the few treatment-free days thereafter. The latter breathing abnormalities and general clinical signs of toxicity were also noted in most decedents. Piloerection was also noted in one surviving male of the 100 mg/kg group. Salivation seen after dosing among animals treated with the test item, in a dose-related manner, was considered to be a physiological response rather than a sign of systemic toxicity considering its slight severity and the time of occurrence (i.e. shortly after dosing).
No additional clinical signs of toxicity were noted during the weekly arena observations.
Any other clinical signs noted incidentally occurred within the range of background findings to be expected for rats of this age and strain which are housed and treated under the conditions in this study and showed no dose-related trend. At the incidence observed, these were considered to be unrelated to treatment.

Dermal irritation (if dermal study):

not examined

Mortality:

mortality observed, treatment-related

Description (incidence):

Severe toxicity was observed at the high dose, leading to the termination of this dose group. At this dose level, there were eight animals euthanized in extremis (male nos. 38, 42, 43 and 51, female nos. 111, 113, 119 and 123, sacrificed between Days 3-13 of treatment). At 100 mg/kg bw/day, one male (no. 30) was euthanized in extremis on Day 14 of treatment and one female (no. 94) was found dead on Day 11 of treatment.

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

Males and females treated at 200 mg/kg bw/day showed reduced body weight gain (statistically significant in males) during their two-week study period. In males this resulted in statistically significantly reduced body weights at study Days 8 and 15. No treatment-related changes in body weights or body weight gain were noted in rats treated up to 100 mg/kg bw/day.

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

Males and females treated at 200 mg/kg bw/day consumed less food than controls throughout their two-week study period. Their food consumption after allowance for body weight showed a similar trend. No treatment-related changes in food consumption before or after allowance for body weight were noted in rats treated up to 100 mg/kg bw/day.

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, non-treatment-related

Description (incidence and severity):

Only data from animals in Groups 1, 2 and 3 (0, 50 and 100 mg/kg bw/day, respectively) were available as the high dose animals (200 mg/kg bw/day; Group 4) had to be euthanized preterm. Haematology parameters were considered not to be affected by treatment up to 100 mg/kg bw/day. The mean number of total white blood cells was lower at 50 and 100 mg/kg bw/day in both sexes. This was statistically significant for males at 50 mg/kg bw/day and females at 100 mg/kg bw/day. However, as all values remained in the historical control range and in the absence of a dose-response relationship, it was not considered treatment-related.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

Only data from animals in Groups 1, 2 and 3 (0, 50 and 100 mg/kg bw/day, respectively) were available as the high dose animals (200 mg/kg bw/day; Group 4) had to be euthanized preterm.

The mean concentration of urea was statistically significantly lower in males at 100 mg/kg compared to controls (4.2 mmol/L versus 5.2 mmol/L; relative difference: 19%). Group mean value was below the available historical control range. The statistically significant change noted for calcium level in males at 50 mg/kg bw/day was considered unrelated to treatment due to the absence of a dose-related trend.

Urinalysis findings:

no effects observed

Description (incidence and severity):

Only data from animals in Groups 1, 2 and 3 (0, 50 and 100 mg/kg bw/day, respectively) were available as the high dose animals (200 mg/kg bw/day; Group 4) had to be euthanized preterm. Urinalysis parameters were considered not to be affected by treatment up to 100 mg/kg bw/day.

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

Only data from animals of Groups 1, 2 and 3 (0, 50 and 100 mg/kg, respectively) were available as the high dose animals (200 mg/kg; Group 4) had to be euthanized preterm.
Hearing ability, pupillary reflex and static righting reflex were normal in all examined animals. Grip strength was not affected by treatment.
The variation in motor activity did not indicate a relation with treatment. All groups showed a similar habituation profile with a decreasing trend in activity over the duration of the test period.
It was noted that the mean values for total movements and ambulations at 50 mg/kg in males were about 1.5-fold higher compared to the control values. In the absence of a dose-related response, these differences were considered to be unrelated to treatment with the test item.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Only data from animals in Groups 1, 2 and 3 (0, 50 and 100 mg/kg bw/day, respectively) were available as the high dose animals (200 mg/kg bw/day; Group 4) had to be euthanized preterm. At microscopic examination of the scheduled sacrifices, test item-related findings were noted in the thymus of males of Group 3 (100 mg/kg bw/day), consisting of minimal degrees of lymphoid atrophy or increased lymphocytolysis. The remainder of the recorded microscopic findings of the scheduled sacrifices were within the range of background pathology encountered in rats of this age and strain. There was no test item related alteration in the prevalence, severity, or histologic character of those incidental tissue alterations.

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Description (incidence and severity):

Thyroid hormone analyses:
Serum levels of T4 in F0 males were considered not to be affected by treatment up to 100 mg/kg bw/day

Reproductive function: oestrous cycle:

effects observed, non-treatment-related

Description (incidence and severity):

Length and regularity of the estrous cycle were considered not to be affected by treatment.

Most females, including those of Group 4 (200 mg/kg bw/day), had regular cycles, generally of four days. Extended di-estrus during pairing occurred in one female (no. 144) of Group 3 (100 mg/kg bw/day) who had regular cycles during the pre-mating period but showed no evidence of mating, probably due to infertility of the male (no. 134). This incidental finding was considered unrelated to treatment. For two females of Group 4 (nos. 113 and 119) cycle length during the pre-mating period could not be determined due to their early death (on Days 3 and 5, respectively).

Reproductive function: sperm measures:

effects observed, non-treatment-related

Description (incidence and severity):

Only one 100-mg/kg bw/day male showed adverse sperm effects, in which lesions in the reproductive organs were noted and could explain the lack of offspring. The main findings for this male consisted of a marked degree of testicular tubular degeneration/atrophy and marked oligospermia in both testes and epididymides. Since these lesions occurred in only one treated male and similar lesions can incidentally be observed as background lesion, they were considered to be unrelated to treatment with the test item.

Reproductive performance:

effects observed, non-treatment-related

Description (incidence and severity):

Precoital time, mating index, fertility index, gestation index, and duration of gestation were not affected by treatment. The number of implantation sites was considered not to be affected by treatment; however, there was a statistically significant decrease in the mean number of implantation sites at 50 mg/kg bw/day, which considered unrelated to treatment due to the absence of a dose-related trend and as it was mainly caused by one female (no. 80) that had only four implantation sites. For female nos. 61 (control) and 76 (50 mg/kg bw/day), the number of pups was (slightly) higher than the number of implantations. This was considered to be due to normal resorption of these areas as these enumerations were performed on Day 16 of lactation.

Mortality:
At 100 mg/kg, one male (no. 30) was euthanized in extremis on Day 14 of treatment and one female (no. 94) was found dead on Day 11 of treatment.
At 200 mg/kg, there were eight animals euthanized in extremis (male nos. 38, 42, 43 and 51, female nos. 111, 113, 119 and 123, sacrificed between Days 3-13 of treatment). Due to this toxicity, the remaining rats of the 200 mg/kg group were no longer dosed from Study Day 11 and were sacrificed a few days later (Study Days 13-15).
Respiratory difficulties (rales, laboured respiration and/or gasping) were noted in all decedents. This was accompanied by hunched posture and/or piloerection in most of them, while a flat posture or chromodacryorrhoea (snout) were noted in one or two decedents.
At macroscopic examination of the 100 mg/kg decedents, no abnormalities were seen in the male while the female found dead showed advanced autolysis. Principal macroscopic findings at 200 mg/kg related to moribundity consisted of emaciation (one female), distension with gas of (parts of) the gastro-intestinal tract (four males and two females), enlarged or thickened lung (one male and one female) and pale discoloration of the lung (two males and one female). In addition, one female at 200 mg/kg (no. 113) was noted with discoloration and dark red gelatinous contents of the small intestine. This necropsy observation together with the microscopic findings of esophagus, trachea and/or glandular stomach erosions were indicative for an irritating property of the test item.
At 100 mg/kg, principal microscopic findings for the two unscheduled deaths were seen in the larynx and consisted of:
- Erosion/necrosis of the epithelium with extension to the underlying tissues, in the male (massive) and the female (moderate).
- Inflammatory cell infiltrate, mainly lymphogranulocytic, in the female (slight).
Principal microscopic findings at 200 mg/kg for the eight unscheduled deaths were seen in the larynx and nasal tissues (in general most obvious in the most caudal levels of the nose):
Larynx:
- Erosion/necrosis of the epithelium with extension to the underlying tissues, in one male (minimal) and three females (marked).
- Inflammatory cell infiltrate, mainly lymphogranulocytic, in three males and four females (up to moderate).
- Luminal exudate, in three females (up to moderate).
- Epithelial hyperplasia, in four males and one female (up to slight).
Nasal tissues:
- Erosions/necrosis of the olfactory epithelium, in four males and one female (up to marked).
- Erosions/necrosis of the respiratory epithelium in four males and one female (up to massive).
- Inflammation, in four males and one female (up to moderate).
- Luminal exudate, granulocytic and/or necrotic and fibrin-like in four males and one female (up to moderate).
- Epithelial metaplasia, in two males and one female (up to moderate).
One female of the control group (no. 67) died at blood sampling prior to scheduled necropsy. As this was a control animal it was not due to treatment with the test item.

Dose descriptor:

NOAEL

Remarks:

systemic

Effect level:

100 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

clinical signs

mortality

body weight and weight gain

gross pathology

histopathology: non-neoplastic

Dose descriptor:

NOAEL

Remarks:

reproductive

Effect level:

>= 100 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no effects observed (reproductive performance could not be examined at 200 mg/kg due to the test item-related early termination of this dose group)

Critical effects observed:

no

Clinical signs:

no effects observed

Description (incidence and severity):

No clinical signs occurred among pups that were considered to be related to treatment.

Dermal irritation (if dermal study):

not examined

Mortality / viability:

mortality observed, non-treatment-related

Description (incidence and severity):

Viability index was not affected by treatment. The viability indices were 99% for the 100-mg/kg bw/day group were 100% for the other groups. The incidental death of one 100-mg/kg bw/day pup was found dead on PND 4 was unrelated to treatment.

Body weight and weight changes:

effects observed, non-treatment-related

Description (incidence and severity):

Body weights of pups were considered not to be affected by treatment up to 100 mg/kg. The higher mean pup weights (statistically significant on PND 1-7) noted in Group 2 (50 mg/kg bw/day) were considered unrelated to treatment due to the absence of a dose-related trend.

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:

effects observed, non-treatment-related

Description (incidence and severity):

Serum T4 levels in male and female PND 13-15 pups were considered not to be affected by treatment. Mean T4 values in 100-mg/kg bw/day male and female pups appeared somewhat lower compared to the control group means. The differences were not statistically significant and could partly be explained by relatively high T4 values in the pups of one litter (no. 61) of the control group. Therefore, these intergroup differences were considered unrelated to treatment with the test item.

Urinalysis findings:

not examined

Sexual maturation:

no effects observed

Description (incidence and severity):

Anogenital distance (absolute and normalized for body weight) in male and female pups was considered not to be affected by treatment.

Treatment up to 100 mg/kg bw/day had no effect on areola/nipple retention. For none of the examined male pups nipples were observed at PND 13.

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

no effects observed

Description (incidence and severity):

No macroscopic findings were noted among surviving pups or pups found dead.

Histopathological findings:

not examined

Other effects:

not examined

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

Dose descriptor:

NOAEL

Generation:

F1

Effect level:

>= 100 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects on offspring were observed (developmental endpoints could not be examined at 200 mg/kg due to the test item-related early termination of this dose group)

Critical effects observed:

no

Reproductive effects observed:

no

Conclusions:

In an oral gavage study conducted to OECD 422 and to GLP (reliability score 1) the NOAEL for 1,2 -ethanediamine, N-{3-(trimethoxysilyl)propyl}-,N-{(ethenylphenyl)methyl}derivs,hydrochlorides relating to repeated dose (parental systemic) effects and to reproductive toxicity was at least 100 mg/kg bw/day, as no significant adverse effects were observed in rats. Rats were dosed with one concentration level higher, 200 mg/kg bw/day, however, this dose group was terminated due to severe toxicity. Toxic effects observed at 200 mg/kg bw/day were attributed to reflux-related problems/direct local exposure rather than direct systemic effects.

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

100 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.7, of Regulation (EC) No 1907/2006.

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 key study (combined repeated dose toxicity study with reproductive/developmental toxicity screening test (oral)) with 1,2 -ethanediamine, N-{3-(trimethoxysilyl)propyl}-,N-{(ethenylphenyl)methyl}derivs,hydrochlorides (CAS 171869-89-9) is available and was performed according to OECD TG 422 and in compliance with GLP (CRL, 2018). The test substance was administered daily in graduate doses (50, 100, or 200 mg/kg bw/day) to 3 groups of test animals per gavage, one dose level per group for a treatment period of up to 55 days, i.e. during two weeks prior to mating, during mating, during post-coitum, and during 13-15 days of lactation. Males were dosed after the mating period until the minimum total dosing period of 29 days was completed. Animals of an additional control group were handled identically as the dose groups but received water, the vehicle used in this study. Due to toxicity in Group 4, resulting in eight unscheduled sacrifices during the pre-mating period, treatment was terminated after 10 days and the surviving animals were sacrificed a few days later.

 

As described in the repeated dose toxicity chapter systemic toxicity was observed in the highest dose group based on mortality, reduced body weight and food consumption and histopathological findings. Because of these findings, the 200-mg/ kg bw/day dose group was terminated. Taken together, up to 100 mg/kg bw/day no item-related adverse effects were observed for the parental animals.

 

No reproduction toxicity was observed up to 100 mg/kg bw/day. At 50 and 100 mg/kg bw/day, non-treatment related changes were noted in any of the reproductive parameters investigated in this study (i.e. mating and fertility indices, precoital time, number of implantation sites, estrous cycle, spermatogenic profiling, and histopathological examination of reproductive organs). Treatment at 200 mg/kg bw/day for 10 days did not result in changes in estrous cyclicity or morphology of male and female reproductive organs. No other reproductive endpoints could be assessed at 200 mg/kg due to the early termination of this dose level. 

 

Based on these results, the reproductive NOAEL was 100 mg/kg bw/day.

Effects on developmental toxicity

Description of key information

Screening study for reproductive/developmental toxicity (OECD 422, oral, rat): NOAEL developmental toxicity = 100 mg/kg bw/day

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

100 mg/kg bw/day

Study duration:

subacute

Species:

rat

Quality of whole database:

The available information comprises an adequate and reliable study, and is thus sufficient to fulfil the standard information requirements set out in Annex VIII, 8.7, of Regulation (EC) No 1907/2006.

Effect on developmental toxicity: via inhalation route

Endpoint conclusion:

no study available

Effect on developmental toxicity: via dermal route

Endpoint conclusion:

no study available

Additional information

A key study (combined repeated dose toxicity study with reproductive/developmental toxicity screening test (oral)) with 1,2 -ethanediamine, N-{3-(trimethoxysilyl)propyl}-,N-{(ethenylphenyl)methyl}derivs,hydrochlorides (CAS 171869-89-9) is available and was performed according to OECD TG 422 and in compliance with GLP (Charles River Laboratories, 2018). The test substance was administered daily in graduate doses (50, 100, or 200 mg/kg bw/day) to 3 groups of test animals per gavage, one dose level per group for a treatment period of up to 55 days, i.e. during two weeks prior to mating, during mating, during post-coitum, and during 13-15 days of lactation. Males were dosed after the mating period until the minimum total dosing period of 29 days was completed. Animals of an additional control group were handled identically as the dose groups but received water, the vehicle used in this study. Due to toxicity in Group 4, resulting in eight unscheduled sacrifices during the pre-mating period, treatment was terminated after 10 days and the surviving animals were sacrificed a few days later.

 

As described in the repeated dose toxicity chapter systemic toxicity was observed in the highest dose group based on mortality, reduced body weight and food consumption and histopathological findings. Because of these findings, the 200-mg/ kg bw/day dose group was terminated. Taken together, up to 100 mg/kg bw/day no item-related adverse effects were observed for the parental animals.

 

No developmental toxicity was observed up 100 mg/kg bw/day. At 50 and 100 mg/kg bw/day, no treatment-related changes were noted in any of the developmental parameters investigated in this study (i.e. gestation, viability and lactation indices, duration of gestation, parturition, sex ratio, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight, anogenital distance (PND 1), areola/nipple retention (PND 13 males), serum level of thyroid hormone T4 (PND 13-15) and macroscopy).

 

Based on these results, the developmental NOAEL was 100 mg/kg bw/day.

Justification for classification or non-classification

According to CLP (1272/2008/EC) classification criteria for repeated dose toxicity, 1,2 -ethanediamine, N-{3-(trimethoxysilyl)propyl}-,N-{(ethenylphenyl)methyl}derivs,hydrochlorides does not fulfill the criteria for classification and thus a non-classification is warranted for this endpoint.