Fatty acids, C14-18 and C16-18-unsatd., 2-phenoxyethyl esters, maleated

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Link to relevant study records

Reference

Endpoint:

one-generation reproductive toxicity

Remarks:

based on generations indicated in Effect levels (migrated information)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented and reported study fully adequate for assessment. The study was conducted according to an internationally accepted technical guideline and in compliance with GLP in a recognized contract research organization.

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

of 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Sprague Dawley rats, strain: Crl:CD(SD) with appropriate range of bodyweight at study start.
- Source: Charles River (UK) Ltd.
- Age at treatment start: ca. 71 days.
- Weight at treatment start: Males: minimum 327 g, maximum 411 g,
Females: minimum 230 g, maximum 271 g.
- Housing Inside a barriered rodent facility:
all animals pre-pairing + toxicity subgroups: In groups up to 5 by sex in solid floor polycarbonate cages.
during pairing (1 male+1 female/cage): In RB3 modified polycarbonate cages with stainless steel grid-floor over absorbent paper-lined trays.
males after pairing: In groups up to 5 in solid floor polycarbonate cages.
females during gestation and lactation: Females housed individually (+litter) in solid floor polycarbonate cages.
- Bedding material (in solid floor cages): Wood based bedding, sterilised by autoclaving before use.
- Cage enrichment: Aspen chew block + plastic shelter (except during pairing or post Gestation Day 20).
- Diet (ad libitum): Standard rodent diet (SDS VRF1 Certified) without antibiotic, chemotherapeutic or prophylactic agent.
- Fasting (diet withheld): Main phase males and Toxicity phase females overnight before blood sampling for clinical pathology*
- Water (ad libitum): Potable drinking water from the public supply.
- Acclimation period: 6 days before treatment start, under laboratory conditions.

Routine analysis of the batch of diet used and water, chew blocks and bedding material did not provide evidence of contamination that might have prejudiced the study.
* Due to clotting of some of the initial blood samples, the bleed for heamatology was repeated without overnight deprivation of food.

IN-LIFE DATES:
- Duration of test, males & toxicity phase females: Five weeks
Duration of test, main phase females (i.e. reproductive subgroup): From 14 days prior to pairing to day 7 of lactation.
Duration of test, offspring: From birth to day 7 of lactation.

ENVIRONMENTAL CONDITIONS

Air conditioned room kept at positve pressure without re-circulation of the filtered fresh air supplied to the room.
Controlled environment, environmental conditions were set at:
- Temperature (°C): 21 ± 2°C
- Relative Humidity (%): 40 to 70%
- Photoperiod (artificial lighting): 12 hrs day / 12 hrs night
- Rate of air exchange: At least 15 changes/h
Deviations from these target ranges for temperature and relative humidity were not evident.

Route of administration:

oral: gavage

Vehicle:

propylene glycol

Details on exposure:

Treatment of parental animals by oral gavage administration. Test substance was not directly administered to F1 animals.

- Concentration in vehicle: The concentration of the test material in vehicle varied between dose groups thus allowing constant dosage volume in terms of mL/kg bw/day.
- Amount (dose volume by gavage): 5 mL/kg bw/day.
Actual dose volumes were calculated at about weekly or shorter intervals accounting for the latest bodyweight.

- For concentrations of test material in vehicle at different dose levels, see Table 1 in "Any other information on materials and methods incl. tables"

- Justification for choice of vehicle:
The suitability of propylene glycol as a vehicle was established during the 7-day range-finding study:
Endpoint study record "7.5.1 Repeated dose toxicity: oral - 7d_range-finding_gavage_HLS_GAH0134".
In addition, in the present main study, concentrations of dose formulations were chemically analysed.

Details on mating procedure:

- Male/female ratio per cage: 1/1
- Length of cohabitation: At the most 4 days, until proof of pregnancy was confirmed. 
- Proof of successful mating: Formation of at least one copulation plug or a sperm positive vaginal smear.
The day this was found was referred to as day 0 of gestation.
(During cohabitation, females were checked every morning for pregnancy).

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Chemical analysis of test material formulations by high performance liquid chromatography coupled with a mass spectrometer (HPLC-MS/MS).
- Mean concentrations (verified for first and last treatment week) of the test material formulations were confirmed at each dose level.
Chemical analysis confirmed that the mean concentrations of WS400109 in prepared formulations were 94% to 104% of the corresponding
nominal concentration, thus confirming acceptable accuracy of formulation for dosing of the animals.
- Homogeneity and stability of test material formulations at 2 and 200 mg/L and at storage and handling conditions similar to those adopted for dosing of the animals were confirmed.

Duration of treatment / exposure:

- Treatment period, males & toxicity phase females: Daily, for five consecutive weeks, in males commencing 14 days prior to pairing
- Treatment period, main phase females (i.e. reproductive subgroup): 42 to 46 days (from 14 days prior to pairing to day 6 of lactation)
- Offspring were not dosed

Frequency of treatment:

Daily, 7 days/week (during parturition, dosing omitted as appropriate)

Details on study schedule:

- Age at mating of the mated animals in the study: 12 to 13 weeks

Remarks:

Doses / Concentrations:
0 (vehicle control), 100, 300, 1000 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

Toxicity phase animals: */ 5 females
Main phase animals (i.e. reproductive subgroups): 10 males / 10 females
*Explanatory note by the notifier:
Examinations assigned to the toxicity phase females to meet the requirements of a 28-day repeat dose oral toxicity study were also assigned to 5 (for some examinations to 10) main phase males per dose group. Therefore, these 5 main phase males per dose group are called also "toxicity subgroup" in the present robust study summary for clarification. After pairing with main phase females, all males (F0) were killed at the same time (Week 6).

Control animals:

yes, concurrent vehicle

Details on study design:

This study was conducted to examine both repeated dose toxicity and  reproductive/developmental toxicity as an OECD screening combined study
(OECD 422 test guideline).  Therefore, animals initially entering the study were divided into toxicity subgroup animals (toxicity phase) and reproductive subgroup animals (main phase), whereby 5 of the 10 F0 males (used for pairing) per dose group formed the toxicity male subgroups.

Dose selection was based on the results of a 7-day preliminary oral toxicity study in the rat in which dose levels of 100, 300 or 1000 mg/kg/day did not have any overt treatment-related effects on young adult animals (females nulliparous and non-pregnant).

Positive control:

Not included in the study.

Parental animals: Observations and examinations:

Clinical observations performed and frequency:
- Clinical signs : At least twice a day (before and after administration)
- Detailed physical examination
and arena observations: Before treatment start and at least once a treatment week.
- Functional Observation Battery: During treatment week 5 (before dosing) on all toxicity subgroup animals (5 parental males/group inclusively)*.
- Body weight, all males: About weekly throughout the study.
Body weight, Toxicity Females: About weekly throughout the study.
Body weight, Repro. Females: Weekly for pre-pairing period; on gestation days 0, 6, 13, 20; on lactation days 1, 4 & 7.
- Food consumption, all males: Weekly for pre-pairing period and for the period after mating.
Food cons., Toxicity Females: About weekly throughout the study.
Food cons., Repro. Females: Weekly for pre-pairing period, during gestation for days 0-6, 6-13, 13-20, during lactation for days 1-4 & 4-7.
- Hematology: During treatment week 5 after functional observation battery*
- Blood (plasma) chemistry: During treatment week 5 after functional observation battery*

* Examinations confined to toxicity subgroup animals are marked above with an asterisk*
and are detailed in the separate endpoint study record "7.5.1 Repeated dose toxicity: oral - Repeat dose tox combined_gavage_rat_HLS_GAH0135"

Explanatory note
This study was conducted to examine both repeated dose toxicity and  reproductive/developmental toxicity as an OECD screening combined study
(OECD 422 test guideline).  Therefore, animals initially entering the study were divided into toxicity subgroup animals (toxicity phase) and reproductive subgroup animals (main phase), whereby 5 of the 10 F0 males (used for pairing) per dose group formed the toxicity male subgroups.

Oestrous cyclicity (parental animals):

Frequency of vaginal oestrus was determined by examination of vaginal smears taken daily from all main phase (i.e. reproductive subgroup) females from the beginning of the treatment period to the day of confirmed copulation.
- Regular: All observed cycles of 4 or 5 days
- Irregular: At least one cycle of 2, 3 or 6 to 10 days
- Acyclic: At least 10 days without oestrus

Sperm parameters (parental animals):

Parameters examined in male parental animals:
- testis weight,
- epididymis weight
- seminal vesicle weight
- detailed qualitative histopathology examination of the testes taking into account the tubular stages of the spermatogenic cycle. This was to identify treatment related effects such as missing germ cell layers or types, retained spermatids, multinucleate or apoptotic germ cells and sloughing of spermatogenic cells in the lumen. Any cell- or stage-specificity of testicular findings was noted.

Litter observations:

STANDARDISATION OF LITTERS: Not performed. The study ended on Lactation Day 7.

LITTER PARAMETERS EXAMINED
- From Day 20 post copulation 3 times a day checks for evidence of parturition, any difficulties and numbers of live and dead offspring.
- Total litter size on day 1 of age and mortality/live litter size on each day until 7 days after littering.
- Sex ratio expressed as percentage males and calculated for total offspring on Day 1 and for live offspring on Days 1, 4 & 7
(No. of male pups in litter/No. of offspring in litter) x 100
- Clinical signs, recorded daily
- Body weight of live pups (on days 1, 4 and 7 after littering) and weight change from Days 1-4, 4-7 and 1-7.

Postmortem examinations (parental animals):

GROSS PATHOLOGY: Yes, see below
WEIGHING OF ORGANS: Yes, see below
HISTOPATHOLOGY: Yes, see below

Terminal sacrifice
- all males (F0) and toxicity subgr. females: Killed in Week 6, after completion of the Treatment Week 5 investigations.
- reproductive subgr. females & offspring: Killed on Day 7 post partum.
(1 control & 1 low dose female were killed on the respective Day 25 after mating, as they had failed to litter)
(1 mid & 1 high dose dam and their litter were killed on the respective Lactation Day 3 for animal welfare
reasons. Their offspring had poor survival prognosis.

Gross pathology:
- adult/parental animals: Full macroscopic examination.

Organs Weights:
- all males (F0) +
toxicity subgroup females: Adrenals, brain, epididymides, heart, kidneys, liver, ovaries, prostate, seminal vesicles with coagulation gland,
spleen, testes, thymus, uterus with cervix & oviducts.
- dams: Ovaries

Histopathology:
- toxicity subgroups*: The following organs were microscopically observed for the control and 1000 mg/kg bw/day groups:
Brain, eyes, pituitary gland, thyroid with parathyroids, heart, thymus, liver, spleen, adrenals, kidneys, testes,
epididymides, ovaries, lung, trachea, oesophagus, stomach, duodenum, jejunum, ileum, caecum, rectum, colon,
Peyer's patch, lymph node (axillary, mesenteric), urinary bladder, uterus (with cervix & oviducts), vagina,
spinal cord, sciatic nerve, skeletal muscle, sternum with marrow, seminal vesicle & coagulation gland, prostate.
In addition, any gross lesions for all adult animals from all dose groups were examined by light microscopy.

* Histopathology examination only on control & high dose groups, 5 males and 5 females per group

- reproductive subgroups Any gross lesions from all adult animals from all dose groups were examined by light microscopy.

Postmortem examinations (offspring):

Pup survivors were killed on Day 7 post partum and had a careful external macroscopic examination for gross abnormalities.

Externally abnormal offspring and premature deaths had an internal macroscopic examination including assessment of the presence of milk in the stomach, where possible. (Missing or grossly autolysed or cannibalised offspring could not be examined).

Statistics:

As detailed in Endpoint study record "7.5.1 Repeated dose toxicity: oral - Repeat dose tox combined_gavage_rat_HLS_GAH0135"

Reproductive indices:

- Pre-coital interval (pairing days until detection of mating)
- No. of animals mating (evidence of successful copulation, i.e. at least one copulation plug or a sperm positive vaginal smear)
- No. of animals achieving pregnancy
- Percentage mating (No. of animals mating/No. of animals paired) x 100
- Fertility index (No. of animals achieving pregnancy/ No. or animals paired) x 100
- Conception rate (No. of animals achieving pregnancy/No. of animals mated) x 100
- Gestation index (No. of live litters born/No. of living animals having achieved pregnancy)
- Gestation length (time elapsing between detection of mating and commencement of parturition)
- No. of living pregnant females
- For further reproductive parameters, see also the above section "Litter observations" and section "Offspring viability indices" below.

Offspring viability indices:

- Post-implantation survival index  (Total no. of pups born/Total no. of uterine implantation sites) x 100
- Live birth index (No. of live pups on Day 1 after littering/Total no. of pups born) x 100
- Viability index (No. of live pups on Day 4 after littering /No. of live pups on Day 1 after littering) x 100
- Lactation index (No. of live pups on Day 7 after littering /No. of live pups on Day 1 after littering) x 100
- For further parameters indicative of the viability of the offspring, see also the above section "Litter observations"

Clinical signs:

no effects observed

Description (incidence and severity):

attributable to treatment with the test material

Body weight and weight changes:

no effects observed

Description (incidence and severity):

attributable to treatment with the test material

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

attributable to treatment with the test material

Organ weight findings including organ / body weight ratios:

no effects observed

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

tissues from toxicity phase females, some parental males & gross lesions histopathologically examined

Other effects:

not examined

Reproductive function: oestrous cycle:

no effects observed

Reproductive function: sperm measures:

no effects observed

Reproductive performance:

no effects observed

CLINICAL SIGNS AND MORTALITY
There were no deaths, early sacrifices or clinical signs attributable to treatment with WS400109. One control and one low dose female were killed on the respective Day 25 after mating, because they had failed to litter. The control female was found not to be pregnant, the low dose female had one dark implantation at macroscopic examination. In addition, one mid and one high dose dam and their litter were killed on the respective Lactation Day 3 for animal welfare reasons, as their offspring had poor survival prognosis.

NEUROBEHAVIOUR
Effects on sensory reactivity or grip strength attributable to treatment with the test material were not evident in toxicity subgroup animals (5 parental males per group inclusive). During treatment week 5, motor activity tended to be higher in toxicity subgroup females (nulliparous and non-pregnant) treated at 1000 mg/kg/day than in concurrent controls, whereby group mean values of the 1000 mg/kg/day dose group often were higher than the upper limit of the historical reference range. Therefore, a similar effect on high dose dams cannot entirely be ruled out. However, any such effect is not a reproductive endpoint and does not represent reproductive toxicity.

BODYWEIGHT, WEIGHT GAIN AND FOOD CONSUMPTION
Food consumption was unaffected by treatment with WS400109. In treated males and main phase females bodyweight, in general, was unaffected. In nulliparous, nonpregnant females (toxicology subgroup) overall bodyweight gain over 5 treatment weeks was higher at 1000 mg/kg/day than in concurrent controls (x 1.39) but this was considered to represent normal biological variation.

REPRODUCTIVE ENDPOINTS
Oestrous cycles, pre-coital interval, mating performance, fertility, gestation length, gestation index and litter size were not affected by treatment.

CLINICAL PATHOLOGY
A number of changes in clinical pathology parameters seen after 5 weeks of treatment in parental males or nulliparous non-pregnant females (toxicology subgroups, 5 animals/sex/group) at 300 and/or 1000 mg/kg/day were not considered to represent adverse effects (detailed in the respective repeat dose toxicity robust study summary) and are not reproductive endpoints.

GROSS PATHOLOGY AND HISTOPATHOLOGY
The numbers of uterine implantation sites in main phase females recorded on Lactation Day 7 were unaffected by treatment with WS400109.

Thickened duodenum and jejunum were macroscopically apparent in two males and one toxicology subgroup female receiving 1000 mg/kg/day. Histopathological correlates to these findings were epithelial hyperplasia in the duodenum and jejunum in both males and in the duodenum in this female. In addition, epithelial hyperplasia and hyperkeratosis were seen at a slightly higher incidence in the nonglandular stomach in both sexes at 1000 mg/kg/day than in concurrent controls. These findings did not represent reproductive endpoints.

Evaluation of the seminiferous testicular tubules regarding their stage in the spermatogenic cycle and regarding the integrity of the various cell types present within the different stages did not reveal any cell or stage abnormalities. Main phase females (reproductive subgroup) killed on Lactation Day 7 were not histopathologically examined.

ORGAN WEIGHTS
Organ weights were unaffected by treatment with WS400109 in males and nulliparous females following 5 treatment weeks, and ovary weights were unaffected in dams on Lactation Day 7.

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: NOEL = highest dose tested.

Clinical signs:

no effects observed

Mortality / viability:

no mortality observed

Body weight and weight changes:

no effects observed

Description (incidence and severity):

on bodyweight or bodyweight gain to Day 7, the day of scheduled sacrifice of the pups.

Sexual maturation:

not specified

Organ weight findings including organ / body weight ratios:

not specified

Gross pathological findings:

no effects observed

Description (incidence and severity):

disclosed by careful external macroscopic examination of all pups surviving to Day 7 and by necropsy of externally abnormal pups and decedents

Histopathological findings:

not examined

There was no indication of any effect of parental treatment with WS400109 on litter size and survival, clinical condition, sex ratio, bodyweight, bodyweight gain or development of the offspring until Lactation Day 7.

One mid and one high dose dam and their litter were killed on the respective Lactation Day 3 for animal welfare reasons. Their offspring had no or little milk in the stomach and were in poor condition, and therefore had poor survival prognosis. All other litters in these dose groups were healthy and survived to scheduled termination on Lactation Day 7. Therefore, these findings were considered to be incidental and not attributable to treatment with WS400109.

Dose descriptor:

NOEL

Generation:

F1

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: NOEL = highest dose tested. Offspring development up to Day 7 of age.

Reproductive effects observed:

not specified

Conclusions:

WS400109 was tested in the rat in a Combined Repeated Dose Oral (Gavage) Toxicity Study with the Reproduction/Developmental Toxicity Screening Test (OECD 422) at dose levels of 0 (vehicle control), 100, 300 and 1000 mg/kg bw/day. The study was terminated on Lactation Day 7. Effects on reproductive and developmental endpoints were not evident. Therefore, in this screening study the no-observed-effect-level (NOEL) regarding reproductive and developmental toxicity was the highest dose level applied, i.e. 1000 mg/kg bodyweight/day. The study results do not warrant the classification of WS400109 regarding reproductive or developmental toxicity according to European classification rules [DIRECTIVE 67/548/EEC and REGULATION (EC) 1272/2008].

Effect on fertility: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

Effect on fertility: via inhalation route

Endpoint conclusion:

no study available

Effect on fertility: via dermal route

Endpoint conclusion:

no study available

Additional information

In this OECD 422 study, oral treatment with WS400109 over at least 5 weeks was generally well tolerated at each dose level with no toxicologically significant systemic effects. The NOEL for fertility and development was the highest dose tested, i.e. 1000 mg/kg/day.

Short description of key information:
WS400109 was tested in the rat in a Combined Repeated Dose Oral (Gavage) Toxicity Study with the Reproduction/Developmental Toxicity Screening Test (OECD 422) at dose levels of 0 (vehicle control), 100, 300 and 1000 mg/kg bw/day. The NOEL regarding fertility was 1000 mg/kg/day, i.e. the highest dose level applied.

Effects on developmental toxicity

Description of key information

WS400109 was tested in the rat in a Combined Repeated Dose Oral (Gavage) Toxicity Study with the Reproduction/Developmental Toxicity Screening Test  (OECD 422) at dose levels of 0 (vehicle control), 100, 300 and 1000 mg/kg bw/day. The study was terminated on Lactation Day 7. The NOEL regarding developmental toxicity was 1000 mg/kg/day, i.e. the highest dose level applied. 

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented and reported study fully adequate for assessment. The study was conducted according to an internationally accepted technical guideline and in compliance with GLP in a recognized contract research organization.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test) of 1996

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Species:

rat

Strain:

Sprague-Dawley

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Sprague Dawley rats, strain: Crl:CD(SD) with appropriate range of bodyweight at study start.
- Source: Charles River (UK) Ltd.
- Age at treatment start: ca. 71 days.
- Weight at treatment start: Males: minimum 327 g, maximum 411 g,
Females: minimum 230 g, maximum 271 g.
- Housing Inside a barriered rodent facility:
all animals pre-pairing + toxicity subgroups: In groups up to 5 by sex in solid floor polycarbonate cages.
during pairing (1 male+1 female/cage): In RB3 modified polypropylene cages with stainless steel grid-floor over absorbent paper-lined trays.
males after pairing: In groups of up to 5 in solid floor polycarbonate cages.
females during gestation and lactation: Females housed individually (+litter) in solid floor polycarbonate cages.
- Bedding material (in solid floor cages): Wood based bedding, sterilised by autoclaving before use.
- Cage enrichment: Aspen chew block + plastic shelter (except during pairing or post gestation day 20).
- Diet (ad libitum): Standard rodent diet (SDS VRF1 Certified) without antibiotic, chemotherapeutic or prophylactic agent.
- Fasting (diet withheld): Main phase males and Toxicity phase females overnight before blood sampling for clinical pathology.
- Water (ad libitum): Potable drinking water from the public supply.
- Acclimation period: 5 days before treatment start, under laboratory conditions.

Routine analysis of the batch of diet used and water, chew blocks and bedding material did not provide evidence of contamination that might have prejudiced the study.

IN-LIFE DATES:
- Duration of test, males & toxicity phase females: Five weeks
Duration of test, main phase females (i.e. reproductive subgroup): From 14 days prior to pairing to day 7 of lactation.
Duration of test, offspring: From birth to day 7 of lactation.

ENVIRONMENTAL CONDITIONS

Air conditioned room kept at positve pressure without re-circulation of the filtered fresh air supplied to the room.
Controlled environment, environmental conditions were set at:
- Temperature (°C): 21 ± 2°C
- Relative Humidity (%): 40 to 70%
- Photoperiod (artificial lighting): 12 hrs day / 12 hrs night
- Rate of air exchange: At least 15 changes/h
Deviations from the target ranges for temperature and relative humidity were not evident.

Route of administration:

oral: gavage

Vehicle:

propylene glycol

Details on exposure:

Treatment of parental animals by oral gavage administration. Test substance was not directly administered to F1 animals.

- Concentration in vehicle: The concentration of the test material in vehicle varied between dose groups thus allowing constant dosage volume in terms of mL/kg bw/day.
- Amount (dose volume by gavage): 5 mL/kg bw/day.
Actual dose volumes were calculated at about weekly or shorter intervals accounting for the latest body weight.

- For concentrations of test material in vehicle at different dose levels, see Table 1 in "Any other information on materials and methods incl. tables"

- Justification for choice of vehicle:
The suitability of propylene glycol as a vehicle was established during the 7-day range-finding study:
Endpoint study record "7.5.1 Repeated dose toxicity: oral - 7d_range-finding_gavage_HLS_GAH0134".
In addition, in the present main study, concentrations of dose formulations were determined by chemical analysis.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

- Chemical analysis of test material formulations by high performance liquid chromatography coupled with a mass spectrometer (HPLC-MS/MS).
- Mean concentrations (verified for first and last treatment week) of the test material formulations were confirmed at each dose level.
Chemical analysis confirmed that the mean concentrations of WS400109 in prepared formulations were 94% to 104% of the corresponding
nominal concentration, thus confirming acceptable accuracy of formulation for dosing of the animals.
- Homogeneity and stability of test material formulations at 2 and 200 mg/L and at storage and handling conditions similar to those adopted for dosing of the animals were confirmed.

Details on mating procedure:

- Male/female ratio per cage: 1/1
- Length of cohabitation: At the most 14 days, until proof of pregnancy was confirmed. 
- Proof of successful mating: Formation of at least one copulation plug and a sperm positive vaginal smear.
The day this was found was referred to as day 0 of gestation.
(During cohabitation, females were checked every morning for pregnancy).

Duration of treatment / exposure:

- Treatment period, males & toxicity phase females: Daily, for five consecutive weeks, in males commencing 14 days prior to mating
- Treatment period, main phase females (i.e. reproductive subgroup): 42 to 46 days (from 14 days prior to pairing to day 6 of lactation)
- Offspring were not dosed

Frequency of treatment:

Daily, 7 days/week (during parturition, dosing omitted as appropriate)

Duration of test:

- Duration of test, all F0 males & toxicity subgroup females: Five weeks
Duration of test, reproductive subgroup females (F0): From 14 days prior to mating to day 7 of lactation.
Duration of test, offspring: From birth to day 7 of lactation.

Remarks:

Doses / Concentrations:
0 (vehicle control), 100, 300, 1000 mg/kg bw/day
Basis:
actual ingested

No. of animals per sex per dose:

Toxicity phase animals: */ 5 females
Main phase animals (i.e. reproductive subgroups): 10 males / 10 females
*Explanatory note by the notifier:
Examinations assigned to the toxicity phase females to meet the requirements of a 28-day repeat dose oral toxicity study were also assigned to 5 (for some examinations to 10) main phase males per dose group. Therefore, these 5 main phase males per dose group are called also "toxicity subgroup" in the present robust study summary for clarification. After pairing with main phase females, all males were killed at the same time (Week 6).

Control animals:

yes, concurrent vehicle

Details on study design:

This study was conducted to examine both repeated dose toxicity and  reproductive/developmental toxicity as an OECD screening combined study
(OECD 422 test guideline).  Therefore, animals initially entering the study were divided into toxicity subgroup animals (toxicity phase) and reproductive subgroup animals (main phase), whereby 5 of the 10 F0 males (used for pairing) per dose group formed the toxicity male subgroups.

Dose selection was based on the results of a 7-day preliminary oral toxicity study in the rat in which dose levels of 100, 300 or 1000 mg/kg/day did not have any overt treatment-related effects on young adult animals (females nulliparous and non-pregnant) necessitating any reduction of target dose levels in the present OECD 422 combined repeat dose toxicity and reprotoxic/develpmental toxicity screening study.

Maternal examinations:

Clinical observations performed and frequency:
- Clinical signs : At least twice a day (before and after administration)
- Detailed physical examination
and arena observations: Before treatment start and at least once a treatment week.
- Body weight: Weekly for pre-pairing period; on gestation days 0, 6, 13, 20; on lactation days 1, 4 & 7.
- Food consumption: Weekly for pre-pairing period, during gestation for days 0-6, 6-13, 13-20, during lactation for days 1-4 & 4-7.
- Frequency of vaginal estrus: Daily by examination of vaginal smears taken from the beginning of the treatment period to the day of confirmed copulation.
(During the pairing period, females were checked every morning for pregnancy).

Additional parameters examined:
- No. of animals mating (evidence of successful copulation, i.e. sperm positive vaginal smear and at least one copulation plug)
- Pre-coital interval (pairing days until detection of mating)
- No. of animals achieving pregnancy
- No. of living pregnant females
- From Day 20 post copulation 3 times a day checks for evidence of parturition, any difficulties and numbers of live and dead offspring.
- Gross pathology
- Organ weights
adrenals, brain, heart, kidneys, liver, lungs & bronchi, ovaries, pituitary, spleen, thymus, thyroids with parathyroids, uterus with cervix & oviducts.
- Histopathology (gross lesions).

Explanatory note
This study was conducted to examine both repeated dose toxicity and  reproductive/developmental toxicity as an OECD screening combined study
(OECD 422 test guideline).  Therefore, animals initially entering the study were divided into toxicity subgroup animals (toxicity phase) and reproductive subgroup animals (main phase), whereby 5 of the 10 F0 males (used for pairing) per dose group formed the toxicity male subgroups.

Ovaries and uterine content:

The ovaries and uterine content were macroscopically examined after termination on day 7 of lactation, i.e. day 7 post partum.
Numbers of uterine implantation sites were recorded and post implantation survival determined.
In addition, gestation length (time elapsing between detection of mating and commencement of parturition) was recorded.

Fetal examinations:

Litters were examined post partum as follows (day of birth = day 0):
- Number:  Daily until day 7 post partum.
- Sex: In total litter: 1st day; in live litter 1st and 7th day
- Live births/mortality: Daily until day 7 post partum.
- Clinical signs: Daily until day 7 post partum
- Body weight of live pups: 1st, 4th, 7th day and weight change from days 1-4, 4-7 and 1-7.
- Necropsy:  7th day full macroscopic examination of all pups including assessment of the presence of milk in the stomach, where possible.
(Missing or grossly autolysed or cannibalised pups could not be examined)

Statistics:

As detailed in Endpoint study record "7.5.1 Repeated dose toxicity: oral - Repeat dose tox combined_gavage_rat_HLS_GAH0135"

Indices:

- Percentage mating (No. of animals mating/No. of animals paired) x 100
- Conception rate (No. of animals achieving pregnancy/No. of animals mated) x 100
- Fertility index (No. of animals achieving pregnancy/ No. or animals paired) x 100
- Gestation index (No. of live litters born on day 0/No. of living pregnant females) x 100
- Post-implantation survival index  (Total no. of pups born/Total no. of uterine implantation sites) x 100
- Live birth index (No. of live pups on day 1 after littering/Total no. of pups born) x 100
- Sex ratio expressed as percentage males and calculated for total offspring on Day 1 and for live offspring on Days 1 & 7
(No. of male pups in litter/No. of offspring in litter) x 100
- Viability index (No. of live pups on day 4 after littering /No. of live pups on day 1 after littering) x 100
- Lactation index (No. of live pups on day 7 after littering /No. of live pups on day 1 after littering) x 100

Historical control data:

For gestation length included in the study report.

Details on maternal toxic effects:

Maternal toxic effects:no effects

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: maternal toxicity

Dose descriptor:

NOEL

Effect level:

1 000 mg/kg bw/day

Based on:

test mat.

Basis for effect level:

other: developmental toxicity

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects:no effects

Abnormalities:

not specified

Developmental effects observed:

not specified

Conclusions:

WS400109 was tested in the rat in a Combined Repeated Dose Oral (Gavage) Toxicity Study with the Reproduction/Developmental Toxicity Screening Test (OECD 422) at dose levels of 0 (vehicle control), 100, 300 and 1000 mg/kg bw/day. The study was terminated on Lactation Day 7. Effects on reproductive and developmental endpoints were not evident. Therefore, in this screening study the no-observed-effect-level (NOEL) regarding reproductive and developmental toxicity was the highest dose level applied, i.e. 1000 mg/kg bodyweight/day. The study results do not warrant the classification of WS400109 regarding reproductive or developmental toxicity according to European classification rules [DIRECTIVE 67/548/EEC and REGULATION (EC) 1272/2008].

Effect on developmental toxicity: via oral route

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subacute

Species:

rat

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

In the OECD 422 Study, it was demonstrated that treatment with WS400109 at doses up to and including 1000 mg/kg bw/day for 35 to 46 days did not induce any effects on reproductive or developmental endpoints. Therefore classification of WS400109 regarding reproductive or developmental toxicity was not warranted according to European classification rules [DIRECTIVE 67/548/EEC and REGULATION (EC) 1272/2008].