Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
screening for reproductive / developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
05 Dec 2019 - 28 Augustus 2020
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2020
Report date:
2020

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)
Version / remarks:
July 2016
Deviations:
no
Qualifier:
according to guideline
Guideline:
other: EPA Health Effects Test Guideline OPPTS 870.3550: Reproduction/Developmental Toxicity Screening Test
Version / remarks:
July 2000
Deviations:
no
Principles of method if other than guideline:
In addition to the collection and examination of reproductive organs, the liver of parental animals was collected, weighted and histopathologically examined.
GLP compliance:
yes
Limit test:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
-
EC Number:
439-270-3
EC Name:
-
Cas Number:
260408-02-4
Molecular formula:
CAS formula: (C12 H10 O4 S . C6 H6 O . Cl5 P . Cl H4 N)x Molecular formula of the reaction products: (C12 H10 N O2 P)n (n=3-15)
IUPAC Name:
439-270-3
Test material form:
solid: particulate/powder
Details on test material:
Physical Description: White powder
Storage Conditions: At room temperature

Test animals

Species:
rat
Strain:
other: Wistar
Remarks:
Crl: WI(Han)
Details on species / strain selection:
The Wistar Han rat was chosen as the animal model for this study as it is an accepted rodent species for toxicity testing by regulatory agencies. Charles River Den Bosch has general and reproduction/developmental historical data in this species from the same strain and source. This animal model has been proven to be susceptible to the effects of reproductive toxicants.
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: 10-11 weeks old (males); 13-14 weeks old (females)
- Weight at study initiation: Males 290 - 330 g; Females: 193 - 246 g;
- Housing: Pretest (females only) and pre-mating period: animals were group housed (up to 5 animals of the same sex and same dosing group together) in polycarbonate cages (Macrolon plastic cages, MIV type)
Mating phase: males and females were cohabitated on a 1:1 basis in Macrolon plastic cages (MIII type)
Post-mating phase: males were housed in their home cage with a maximum of 5 males/cage
(Macrolon plastic cages, MIV type); females were individually housed in Macrolon plastic cages(MIII type).
Lactation phase: females were housed in Macrolon plastic cages (MIII type). Pups were housed with the dam.

The cages contained appropriate bedding and were equipped with water bottles. Animals were socially housed for psychological/environmental enrichment and were provided with items such as devices for hiding in, paper and/or objects for chewing, except when interrupted by study procedures/activities.

- Diet: ad libitum (except during designated procedures); Pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany). The feed was analyzed by the supplier for nutritional components and environmental contaminants. Results of the analysis were provided by the supplier and are on file at the Test Facility. It is considered that there were no known contaminants in the feed that would interfere with the objectives of the study.
- Water: ad libitum; Municipal tap water. Periodic analysis of the water was performed and results of these analyses are on file at the Test Facility. It is considered that there were no known contaminants in the water that would interfere with the objectives of the study.

- Acclimation period: 8 days prior to start of the pretest period (females) and 6 days before the commencement of administration (males).

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 -20
- Humidity (%): 47 -58
- Air changes (per hr): 10 or more
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 14 Jan 2020 To: 17 Mar 2020

Administration / exposure

Route of administration:
oral: feed
Vehicle:
acetone
Details on exposure:
DIET PREPARATION
The test item was mixed with the use of a vehicle acetone (7:13 ratio w/v) and premixed with a small amount (~1-2 kg) of powder feed for one hour (± 5 minutes). Subsequently this premix was mixed for approximately 10 minutes with the remaining amount of powder diet. Standard powder rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest,Germany) was used. After mixing, the diet was incubated overnight at room temperature before use and storage, to evaporate the acetone.

- Rate of preparation of diet (frequency): Diets were prepared for use at room temperature for a maximum of 10 days in open containers. Diets were kept at room temperature until use.
Any remaining food left after filling the food hoppers was stored at room temperature for a maximum of 3 weeks from the day of preparation for supplementing or changing food during the respective food consumption measurement interval.
- Storage temperature of food: room temperature

Details on mating procedure:
- M/F ratio per cage: 1:1 basis within the same treatment group
- Proof of pregnancy: evidence of sperm in the vaginal lavage or by the appearance of an intravaginal copulatory plug. This day was designated Day 0 post-coitum.
- After successful mating each pregnant female was caged: individually
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Samples used for concentration and homogeneity analysis were analyzed using a UPLC system (UV detector)

Duplicate sets of samples (approximately 5 g) were used for concentration analysis.
Duplicate sets of samples (approximately 5 g) for each sampling time point were used for homogeneity analysis.

The concentration results were considered acceptable if mean sample concentration results were within or equal to ±20% for diet of target concentration.

Homogeneity results were considered acceptable if the coefficient of variation (CV) of concentrations was ≤10%.

Stability analyses was performed previously in conjunction with the method development and
validation study (Test Facility Study No. 20208940),
Duration of treatment / exposure:
The test item was administered to the appropriate animals by inclusion in the diet ad libitum from Day 1 onwards for a minimum of 28 days. Males were exposed for 29 days, up to and including the day before scheduled necropsy. This included a minimum of 14 days prior to mating and during the mating period. Females were exposed for 50-63 days, i.e. 14 days prior to mating (to cover at least two complete estrous cycles), the variable time to conception, the duration of pregnancy and at least 13 days after delivery, up to and including the day of scheduled necropsy. Females which failed to deliver or had a total litter loss were treated for 52 days.
Frequency of treatment:
daily, 7 days a week.
Doses / concentrationsopen allclose all
Dose / conc.:
1 500 ppm (analytical)
Remarks:
Group 2
Dose / conc.:
4 500 ppm (analytical)
Remarks:
Group 3
Dose / conc.:
15 000 ppm (analytical)
Remarks:
Group 4
No. of animals per sex per dose:
10/sex/dose
Control animals:
yes, plain diet
Details on study design:
- Dose selection rationale: The dose levels were selected based on the results of a 14-day Dose Range Finder with dietary administration of SPS-100 in rats
- Fasting period before blood sampling for clinical biochemistry: F0-males were fasted overnight with a maximum of approximately 24 hours before blood
sampling, but water was available. F0- females were not fasted overnight

Examinations

Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: twice daily

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: once daily
During the dosing period, these observations were performed after dosing at no specific time point, but within a similar time period after dosing for the respective animals (no peak effect of occurrence of clinical signs was observed in the dose range finder).

BODY WEIGHT: Yes
- Time schedule for examinations: Animals were weighed individually on the first day of administration, 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
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes
- Food consumption was quantitatively measured 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, 10 and 13.

OTHER:
- Water consumption was monitored on regular basis throughout the study by visual inspection of the water bottles

-Thyroid hormones
Oestrous cyclicity (parental animals):
Time schedule: daily, for all females beginning 14 days prior to treatment and the first 14 days of treatment and during mating until evidence of copulation was observed
- Examination: examining the vaginal cytology of samples obtained by vaginal lavage. On the day of necropsy, a vaginal lavage was also taken to determine the stage of estrous.
Sperm parameters (parental animals):
Parameters examined in male parental generations: testis weight, epididymis weight.
For the testes of all selected males of Groups 1 and 4, and all males that failed to sire, a detailed qualitative examination was made, taking into account the tubular stages of the spermatogenic cycle.
Litter observations:
STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: yes
- Maximum of 8 pups/litter 4/sex/litter (as nearly as possible); excess pups were euthanized.

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
Mortality, clinical signs (at least once daily), body weights (PND 1, 4, 7 and 13), sex (externally determined on PND 1 and 4), Anogenital distance (AGD) on PND 1, presence of nipples/areolae in male pups (PND 13).

THYROID HORMONE ANALYSIS
On PND 4 at culling, blood was collected from two surplus pups per litter and samples were pooled to one sample per litter. On PND 14-16, separate blood samples were collected from two pups per litter. Blood samples were processed for serum and analyzed for total Thyroxine (T4). Assessment of T4 for PND 4 pups and Thyroid Stimulating Hormone (TSH) for PND 14-16 pups was considered not relevant because no treatment-related changes in T4 were noted in pups at PND 14-16.
Postmortem examinations (parental animals):
SACRIFICE
- Male animals: All surviving animals after a minimum of 28 days of administration.
- Maternal animals: All surviving animals, PND 14-16 or without evidence of mating: 24 days after the last day of the mating period.

GROSS PATHOLOGY: Yes
- All animals were subjected to a full post mortem examination, with special attention being paid to the reproductive organs.

ORGAN WEIGHTS: Yes
- Organs weighed for all animals: epididymis, coagulation gland, parathyroid gland, prostate gland, seminal vesicle gland, thyroid gland, liver, testes

HISTOPATHOLOGY: Yes
All animals: Gross lesions/masses and liver
All animals of Groups 1-4: Epididymis, thyroid gland, ovaries and testes.
Males that failed to sire and females that failed to delivery pups: cervix, epididymis gland, coagulation gland, prostate gland, seminal vesicle gland, thyroid gland, gross lesions/masses, liver, ovaries, testes, uterus, vagina

For the testes of all males of Groups 1 and 4, and all males that failed to sire, a detailed qualitative examination was made, taking into account the tubular stages of the spermatogenic cycle.

Postmortem examinations (offspring):
SACRIFICE
Pups that died before scheduled termination were examined externally and sexed (both externally and internally). 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.
- On PND 4, the surplus pups (> 8 pups per litter) were euthanized. All remaining pups were euthanized on PND 14-16 and were subjected to postmortem examinations (macroscopic and/or microscopic examination) as follows: Sex was determined both externally and internally. Descriptions of all external abnormalities were recorded. Particular attention was paid to the external reproductive genitals to examine signs of altered development.
Statistics:
STATISTICAL ANALYSIS
All statistical tests will be conducted at the 5% significance level. All pairwise comparisons will be conducted using two sided tests and will be reported at the 1% and 5% levels.
Numerical data collected on scheduled occasions will be analyzed according to sex and occasion. Descriptive statistics number, mean and standard deviation will be reported whenever possible. Values may also be expressed as a percentage of predose or control values when deemed appropriate. Inferential statistics will be performed according to the matrix below when possible, but will exclude semi-quantitative data, and any group with less than 3 observations.
The following pairwise comparisons will be made:
Group 2 vs. Group 1
Group 3 vs. Group 1
Group 4 vs. Group 1

Parametric
Datasets with at least 3 groups (the designated control group and 2 other groups) will becompared using Dunnett-test (many-to-one-t-test).

Non-Parametric
Datasets with at least 3 groups will be compared using a Steel-test (many-to-one rank test).

Incidence
An overall Fisher’s exact test will be used to compare all groups. The above pairwise comparisons will be conducted using Fisher’s exact test whenever the overall test is significant.
Reproductive indices:
Mating index (%): (Number of females mated/Number of females paired) x 100
Precoital time: Number of days between initiation of cohabitation and confirmation of mating
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
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

Results and discussion

Results: P0 (first parental generation)

General toxicity (P0)

Clinical signs:
no effects observed
Description (incidence and severity):
No clinical signs were noted during daily detailed clinical observations after treatment with the test item up to 15000 ppm.
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Description (incidence and severity):
Body weights and body weight gain of treated animals remained in the same range as controls over the treatment period up to 15000 ppm.
Food consumption and compound intake (if feeding study):
effects observed, non-treatment-related
Description (incidence and severity):
No toxicologically relevant changes in food consumption before or after correction for body weight were recorded up to 15000 ppm.
At 4500 ppm in females, mean food consumption after correction for body weight was increased (1.11x of control) between post-coitum Days 14-17. This change was considered to be unrelated to treatment with the test item since no trend was apparent regarding dose and duration of treatment.
Organ weight findings including organ / body weight ratios:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Description (incidence and severity):
There were no test item-related microscopic observations. All the recorded microscopic findings were within the range of background pathology encountered in rats of this age and strain.
Other effects:
no effects observed
Description (incidence and severity):
Serum levels of T4 in F0-males were considered unaffected by treatment with the test item up to 15000 ppm.

Reproductive function / performance (P0)

Reproductive function: oestrous cycle:
no effects observed
Description (incidence and severity):
Length and regularity of the estrous cycle were considered not to have been affected by treatment with the test item up to 15000 ppm. All females had regular cycles of 4 days.
Reproductive function: sperm measures:
no effects observed
Description (incidence and severity):
Stage dependent qualitative evaluation of spermatogenesis in the testis was performed. The testis revealed normal progression of the spermatogenic cycle and the expected cell associations and proportions in the various stages of spermatogenesis were present.
Reproductive performance:
no effects observed
Description (incidence and severity):
There was 1/10 couples at 1500 ppm and 1/10 couples at 4500 ppm that did not mate and therefore had no offspring. No abnormalities were seen in the reproductive organs, which could account for their lack of offspring.

Mating index was considered not to be affected by treatment with the test item up to 15000 ppm. The mating indices were 100, 90, 90 and 100% for the control, 1500, 4500 and 15000 ppm groups, respectively.

Precoital time was considered not to be affected by treatment with the test item up to 15000 ppm. All females showed evidence of mating within 4 days, except for one female at 15000 ppm which showed evidence of mating within 13 days and one female at 1500 ppm and one female at 4500 ppm which did not show evidence of mating. Since these cases of not mated showed no dose related incidence across the dose groups, and given the absence of any reproductive/developmental toxicity, this was considered not to be related to treatment.

Number of implantation sites was considered not to be affected by treatment with the test item up to 15000 ppm.

Fertility index was not affected by treatment with the test item up to 15000 ppm. The fertility indices were 100% for all groups.

Gestation index and duration of gestation were considered not to be affected by treatment with the test item up to 15000 ppm. The gestation index was 100% for all groups.

No signs of difficult or prolonged parturition were noted among the pregnant females. Examination of cage debris of pregnant females revealed no signs of abortion or premature birth. No deficiencies in maternal care were observed.

Effect levels (P0)

open allclose all
Key result
Dose descriptor:
NOAEL
Remarks:
parental
Effect level:
> 15 000 ppm (analytical)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: Absence of adverse effects up to and including the highest dose level tested.
Key result
Dose descriptor:
NOAEL
Remarks:
reproduction
Effect level:
> 15 000 ppm (analytical)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
other: Absence of adverse effects up to and including the highest dose level tested.

Target system / organ toxicity (P0)

Critical effects observed:
no

Results: F1 generation

General toxicity (F1)

Clinical signs:
no effects observed
Description (incidence and severity):
No clinical signs occurred among pups that were considered to be related to treatment with the test item up to 15000 ppm.
One pup in the control group was missing on Day 2, absence of milk in the stomach was noted on Day 1.
The nature and incidence of this and other clinical signs remained within the range considered normal for pups of this age, and were therefore considered not to be toxicologically relevant.
Mortality / viability:
mortality observed, non-treatment-related
Description (incidence and severity):
The number of live offspring on Day 1 after littering compared to the total number of offspring born was considered not to be affected by treatment with the test item up to 15000 ppm. The live birth indices were 95, 100, 100 and 100% for the control, 1500, 4500 and 15000 ppm groups, respectively. Seven pups (all from one litter) of the control group were found dead at first litter check. No toxicological relevance was attributed to these dead pups since it occurred in the control group.

The number of live offspring on Day 4 before culling compared to the number of offspring on Day 1 was considered not affected by treatment with the test item up to 15000 ppm.
Viability indices were 97, 99, 98 and 99% for the control, 1500, 4500 and 15000 ppm groups, respectively.

Four pups of the control group, one pup at 1500 ppm, two pups at 4500 ppm and one pup at 15000 ppm were found dead or missing on PND 2 or 3. Pups missing were most likely cannibalized. No toxicological relevance was attributed to these dead/missing pups since the
mortality incidence did not show a dose-related trend and remained within the range considered normal for pups of this age.

The number of live offspring on Day 13 after littering compared to the number of live offspring on Day 4 (after culling) was considered not to be affected by treatment with the test item up to 15000 ppm.

The lactation indices were 99, 100, 100 and 100% for the control, 1500, 4500 and 15000 ppm groups, respectively.

One male pup (control group) was found missing on PND 13. This missing pup was most likely cannibalized. No toxicological relevance was attributed to this missing pup since it occurred in the control group.
Body weight and weight changes:
no effects observed
Description (incidence and severity):
Body weights of pups were considered not to be affected by treatment.
Clinical biochemistry findings:
no effects observed
Description (incidence and severity):
Serum T4 levels in male and female PND 14-16 pups were considered not to be affected by treatment with the test item up to 15000 ppm.
Anogenital distance (AGD):
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 with the test item up to 15000 ppm.
Nipple retention in male pups:
no effects observed
Description (incidence and severity):
Treatment up to 15000 ppm had no effect on areola/nipple retention. For none of the examined male pups nipples were observed at PND 13.
Gross pathological findings:
no effects observed
Description (incidence and severity):
No macroscopic findings were noted among pups that were considered to be related to treatment with the test item up to 15000 ppm.
Other effects:
no effects observed
Description (incidence and severity):
Litter size was considered not affected by treatment with the test item up to 15000 ppm. Live litter sizes were 12.4, 11.9, 12.9 and 12.4 living pups/litter for the control, 1500, 4500 and 15000 ppm groups, respectively.

Effect levels (F1)

Dose descriptor:
NOAEL
Remarks:
Developmental
Generation:
F1
Effect level:
> 15 000 ppm (analytical)
Based on:
test mat.
Sex:
not specified
Basis for effect level:
other: absence of adverse effects up to and including the highest doe levels tested.

Target system / organ toxicity (F1)

Critical effects observed:
no

Overall reproductive toxicity

Key result
Reproductive effects observed:
no

Any other information on results incl. tables

Test Article Intake


















































































 



 



 



Mean over means intake 


[mg test item/kg body weight]


(mean range indicated within brackets)



 



Group No.



 



2



 



3



 



4



 



Nominal dietary inclusion level (ppm)



 



1500



 



4500



 



15000



Sex



 


Study period



 



 



 



 


 



 



 



Males



Pre-mating Post-mating



109


102



(108-110) (96-109)



332


302



(328-337)


(294-309)



1098


1028



(1092-1104) (997-1059)



 



Mean of means(1)



 



106



 



317



 



1063



Females



 


Pre-mating


Post-coitum


Lactation



109


114


219



(108-110)


(101-125)


(175-257)



331


348


678



 


(329-333)


(317-362)


(549-795)



1123


1141


2266



(1117-1129)


(1045-1228)


(1856-2660)



 



Mean of means(1)



 



140



 



429



 



1429



(1)Mean of means of all periods, weighed for number of days per period:


Males: ((14 x mean premating) + (14 x mean mating)) / 28


Females: ((14 x mean premating) + (20 x mean post-coitum) + (12 x mean lactation)) / 46


 


DRF


A dose range finder (Test Facility Reference No. 20208941) was conducted to select dose levels for the Main study (Test Facility Study No. 20208942), and to determine the peak effect of occurrence of clinical signs after dosing. No guidelines were applicable as this study was intended for dose level selection purposes only.


If not mentioned otherwise, test system, procedures and techniques were identical to those used during the main study.


Dosing of the DRF was initiated on 05 Dec 2019. The in-life phase of the DRF was completed on 20 Mar 2020.


 


Diet Preparations


Samples for diet analysis were not collected during the dose range finder, as concentration, homogeneity, and stability analysis was not performed. Homogeneity and stability of the diet under test conditions was demonstrated in the analyticalmethod development and validation study.


 


Test System


On 27 Nov 2019 female Crl: WI(Han) rats were received from Charles River Deutschland, Sulzfeld, Germany. Females were 12-13 weeks old and weighed between 187 and 198 grams at initiation of administration. On arrival and following assignment to groups at random at the discretion of the biotechnician, animals were group housed (up to 3 animals of the same dosing group together) in polycarbonate cages (Macrolon, MIV type, height 18 cm). At study assignment each animal was identified using earmark and tailmark. The actual daily mean temperature during the study period was 20 to 21°C with an actual daily mean relative humidity of 50 to 53%.


 


Experimental Design DRF


Group no.1 (3 females) - 7500 ppm - Mean of means 570 mg/kg bw/day


Group no.2 (3 females) - 15000 ppm - Mean of means 1241 mg/kg bw/day


The test item was administered to the appropriate animals by inclusion in the diet ad libitum from Day 1 onwards for a minimum of 14 days.


The dose levels were selected based on the results of 28-day repeated dose toxicity study of SPS-100 in the mammal (Project No. H98606 Nippon Experimental Medical Research Institute Co., Ltd.).


 


In-life Procedures


Mortality: Twice daily throughout the study.


Clinical Observations: At least once daily up to the day prior to necropsy.


Body Weights: On Day 1 prior to first administration and on Days 4, 8, 11 and 14.


Food Consumption: Days 1-4, 4-8, 8-11 and 11-14.


Terminal Procedures


All animals were subjected to an external, thoracic and abdominal examination on Day 15 (scheduled necropsy). Animals were not deprived of food prior to necropsy. Terminal bodyweight, kidney and liver weight were determined at scheduled necropsy. No organs were fixed and histopathological examination was not performed.


RESULTS


No signs of toxicity were noted at any dose level.


 









































Parameter



7500 ppm



15000 ppm



Mortality



No mortality.



No mortality.



Clinical appearance



No findings.



No findings.



Body weight



 


Normal.



Normal.



Food consumption



Normal.



Normal.



Macroscopic examination



No abnormalities noted.



No abnormalities noted.



Organ weights



Liver and kidney weights considered to be normal.



Liver and kidney weights considered to be normal.



CONCLUSION


Based on the results of the dose range finder, selected dose levels for the Main study were 1500, 4500 and 15000 ppm.


 


Result diet preparation analysis


The concentrations analysed in the diets of Groups 2, 3 and 4 were in agreement with target concentrations (i.e. mean accuracies between 80% and 120%). No test item was detected in the Group 1 (control) diet. (actual: 98%, 97%, 99% in groups 2, 3 and 4, respectively).


The diets of Groups 2 and 4 were homogeneous (coefficient of variation ≤ 10%) (actual: 2.3% and 1.0 in groups 2 and 4, respectively).


The test item was shown to be stable in the diet when prepared and stored under the same conditions at concentrations used in the present study (refer toTest Facility Study No. 20208940).


 


 


 

Applicant's summary and conclusion

Conclusions:
Based on the results of a Reproduction/Developmental Toxicity Screening Test, performed according to OECD TG 421 and in accordance with GLP principles, the parental and reproduction NOAEL of SPS-100 is considered to be at least 15000 ppm (corresponding to an actual test article intake of 1063 and 1429 mg/kg bw/day for males and females, respectively) based on the absence of adverse effects up to and including the highest dose level tested.
Executive summary:

A Reproduction/Developmental Toxicity Screening Test was performed according to OECD TG 421 and in accordance with GLP principles. Male and female rats (10/dose) were exposed via diet to 0 (control), 1500, 4500, 15000 ppm of SPS-100. Dietary analyses confirmed that dietary preparations of test item in acetone were prepared accurately and homogenously. There were no unscheduled deaths. No parental toxicity was observed up to and including the highest dose level tested (15000 ppm). No treatment-related changes were noted in any of the remaining parameters investigated in this study (i.e. mortality, clinical signs, body weight and food consumption, estrous cycle determination, measurement of thyroid hormone T4 (F0-males), gross necropsy findings, organ weights and, histopathologic examinations). No treatment-related changes were noted in any of the reproduction/developmental parameters investigated in this study (i.e.gestation index and duration, parturition, maternal care, sex ratio and early postnatal pup development mortality, clinical signs, body weights,  anogenital distance, areola/nipple retention, macroscopy and measurement of thyroid hormone T4). In conclusion, based on the results of the reproduction/developmental toxicity screening test, the parental and reproductive NOAEL of SPS-100 is considered to be at least 15000 ppm (corresponding to an actual test article intake of 1063 and 1429 mg/kg bw/day for males and females, respectively).