Oxacycloheptadecan-2-one

Endpoint summary

Key value for chemical safety assessment

Effects on fertility

Description of key information

In a GLP-compliant OECD guideline 422 study with rats, no adverse effects on reproduction were observed at the highest tested dose of 1000 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:

6 September 2016 - 5 December 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

March 1996

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)

Version / remarks:

July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650, Combined Repeated Dose Toxicity with the Reproduction/Developmental Toxicity Screening Test

Version / remarks:

July 2000

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3550, Reproduction/Developmental Toxicity Screening Test

Version / remarks:

July 2000

Deviations:

no

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
In refrigerator (2-8°C)
- Stability at higher temperatures: yes, maximum temperature: 40°C, maximum duration: 20 minutes
- Solubility and stability of the test substance in the solvent/vehicle:
stability in corn oil for at least 6 hours at room temperature, under normal laboratory light conditions is confirmed over the concentration range 1 to 200 mg/mL in a separate study
- Specific gravity 0.977 g/mL at 20 °C
- No correction for purity required


FORM AS APPLIED IN THE TEST (if different from that of starting material)

The test item was heated up to a maximum of 39ºC for a maximum of 23 minutes during the preparation of formulations.

Species:

rat

Strain:

other: Crl:WI(Han)

Details on species / strain selection:

This species and strain of rat has been recognized as appropriate for general and reproduction toxicity studies. 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
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation:
Approximately 10-11 weeks
- Weight at study initiation:
males 272-321 g, females 179-228 g
- Fasting period before study:
no
- Housing:
Sterilized sawdust as bedding material and paper as cage-enrichment/nesting material were supplied, except during locomotor activity measurements.
Pre-mating: in groups of 5 animals/sex/cage in Macrolon plastic cages MIV type
Mating: on 1:1 basis m:f in MIII type Macrolon cages
Post-mating: males in their home cages with a maximum of 5 animals/cage, females individually in MIII type Macrolon cages
Lactation: pups with the dam in Macrolon MIII type cages, except during locomotor activity monitoring of the dams the pups were kept warm in their home cage using bottles filled with warm water. In order to avoid hypothermia of pups, pups were not left without their dam or a bottle filled with warm water for longer than 30-40 minutes.
Locomotor activity measurements: individually in polycarbonate cages without cage-enrichment, bedding material, food and water.
- Diet: pelleted rodent diet (SM R/M-Z from SSNIFF®), ad libitum, except during locomotor measurements
- Water: tap water, ad libitum, except during locomotor measurements, when animals did not have access to water for a maximum 1 hour and 23 minutes.
- Acclimation period:
At least 5 days prior to start of treatment

DETAILS OF FOOD AND WATER QUALITY:
Diet, water, bedding and cage-enrichment/nesting material evaluation for contaminants and/or nutrients was performed according to facility standard procedures. There were no findings that could interfere with the study.

ENVIRONMENTAL CONDITIONS
(set to maintain)
- Temperature (°C):
18-24
- Humidity (%):
40-70
- Air changes (per hr):
at least 10
- Photoperiod (hrs dark / hrs light):
12/12

IN-LIFE DATES: From: 06 Sepmeber 2016 To: 05 December 2016

Route of administration:

oral: gavage

Vehicle:

corn oil

Details on exposure:

- PREPARATION OF DOSING SOLUTIONS:
Adjustment was made for specific gravity of the vehicle. No correction was made for the purity/composition of the test item.
Formulations (w/w) were prepared daily within 6 hours prior to dosing and were homogenized to a visually acceptable level. The test item was heated up to a maximum of 39 ºC for a maximum of 23 minutes. In order to obtain homogeneity, the test item in vehicle was heated up to a maximum temperature of 42 ºC for a maximum of 35 minutes. The formulations were allowed to cool down to a temperature of maximally 40 ºC prior to dosing.

- VEHICLE
- Justification for use and choice of vehicle:
based on trial formulations performed at Charles River Den Bosch
- Amount of vehicle (if gavage):
5 mL/kg bw
- Specific gravity: 0.92

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: maximum 12 days
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 post-coitum
- After successful mating each pregnant female was caged individually in Macrolon type III cages

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses were conducted on a single occasion during the treatment phase according to a validated method. Samples of formulations were analyzed for homogeneity (highest and lowest concentration) and accuracy of preparation (all concentrations).
The accuracy of preparation was considered acceptable if the mean measured concentrations were 90-110% of the target concentration. Homogeneity was demonstrated if the coefficient of variation was ≤ 10%.

Duration of treatment / exposure:

Males: 31 days, i.e. 2 weeks prior to mating, during mating, and up to the day prior to scheduled necropsy.
Females that delivered: 41-52 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 least 4 days after delivery up to and including the day before scheduled necropsy.
Two females that failed to deliver (low- and high-dose groups): 40 and 42 days, respectively

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.

Details on study schedule:

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

Dose / conc.:

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

Remarks:

Concurrent vehicle controls, Group 1

Dose / conc.:

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

Remarks:

Group 2

Dose / conc.:

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

Remarks:

Group 3

Dose / conc.:

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

Remarks:

Group 4

No. of animals per sex per dose:

10/sex/dose

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on results of a 10-day dose range finding study

Positive control:

Not applicable for this study design

Parental animals: Observations and examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule:
at least twice daily for mortality and viability

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule:
at least once daily from start of treatment onwards up to the day prior to necropsy after dosing at no specific time point, but within a similar time period after dosing for the respective animals. 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.

BODY WEIGHT: Yes
- Time schedule for examinations:
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 and 4. In addition, for the females for which mating was overlooked one additional body weight measurement was performed.

FOOD CONSUMPTION AND COMPOUND INTAKE: yes
- Time schedule for examinations: 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 and 4.


FOOD EFFICIENCY:
no

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Subjective appraisal was maintained during the study, but no quantitative investigation was introduced, as no treatment related effect was suspected.

OTHER:

HAEMATOLOGY: Yes
- Time schedule for collection of blood:
at the end of the treatment period on the day of scheduled necropsy
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes, overnight for maximum 24 hours; water was available.
- How many animals:
selected 5 animals/sex/group
- Parameters examined: WBC, differential leucocyte count (neutrophils, lymphocytes, monocytes, eosinophils, basophils), RBC, reticulocytes, RDW, haemoglobin, haematocrit, MCV, MCH, MCHC, platelets; PT, APTT

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood:
at the end of the treatment period on the day of scheduled necropsy
- Animals fasted: Yes, overnight for maximum 24 hours; water was available.
- How many animals:
selected 5 animals/sex/group
- Parameters examined: ALAT, ASAT, ALP, total protein, albumin, total bilirubin, bile acids, urea, creatinine, glucose, cholesterol, sodium, potassium , chloride, calcium, inorganic phosphate

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations:
selected males during week 4, selected females towards the end of the scheduled lactation period (from lactation Day 4 onwards)
- Dose groups that were examined:
all dose levels, selected 5 animals/sex/group
- Battery of functions tested: sensory activity (hearing, pupillary reflex, static rightling reflex, fore- and hind limb grip strength, motor activity (total movements and ambulations)

Oestrous cyclicity (parental animals):

Not examined.

Sperm parameters (parental animals):

Parameters examined in P male parental generation:
testis weight, epididymis weight, histopathological examination of testes slides to examine staging of spermatogenesis (PAS/haematoxylin staining)

Litter observations:

STANDARDISATION OF LITTERS
- Performed on day 4 postpartum: no, necropsy of all pups on PND 5-7

PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross anomalies, litter/body weight, physical or behavioural abnormalities

GROSS EXAMINATION OF DEAD PUPS:
yes, for external and internal abnormalities; possible cause of death was determined for pups born or found dead. The stomach of pups not surviving to the scheduled necropsy date was examined for the presence of milk, if possible.

ASSESSMENT OF DEVELOPMENTAL NEUROTOXICITY: not performed

ASSESSMENT OF DEVELOPMENTAL IMMUNOTOXICITY: not performed

Postmortem examinations (parental animals):

SACRIFICE
- Male animals: All surviving animals following completion of the mating period (a minimum of 28 days of dose administration).
- Females that delivered: PND 5-7
- Females that failed to deliver: Post-coitum Days 25 or 27 (females with evidence of mating).
- Females with total litter loss: Two days after litter loss
- One female euthanized in extremis: day 24 post-coitum

GROSS NECROPSY: Yes, full post mortem necropsy was performed , with special attention being paid to the reproductive organs.

ORGAN WEIGHTS: Yes
The following organ weights were recorded:
Selected 5 animals/sex/group: adrenal glands, brain, epididymides, heart, kidneys, liver, ovaries, prostate, seminal vesicles including coagulating glands, spleen, testes, thymus, thyroid including parathyroid, uterus including cervix.
All other animals: epididymides, testes

HISTOPATHOLOGY: Yes
The following tissues were examined by histopathologist:

On selected 5 animals/sex/group from controls and high-dose group: adrenal glands, brain (cerebellum, mid brain, cortex (7-levels), caecum, cervix, clitoral gland, colon, coagulation gland, duodenum, epididymides, eyes with optic nerve, if detectable, and Harderian gland; female mammary gland area, femur including joint, heart, ileum, jejunum, kidneys, liver, lungs, lymph nodes (mandibular, mesenteric), ovaries, Peyers patches (jejunum, ileum) if detectable, pituitary gland, preputial gland, prostate gland, sciatic nerve, seminal vesicles, skeletal muscle, spinal cord (cervical, midthoracic, lumbar), spleen, sternum with bone marrow, stomach, testes, thymus, thyroid including parathyroid if detectable, trachea, urinary bladder, uterus, vagina, all gross lesions
On selected 5 males/group from controls and high dose group, and all males that failed to sire: additional testes slides
On the female euthanized in extremis: all preserved organs and tissues
On all males that failed to sire and all females that failed to deliver healthy pups: reproductive organs
On the female with total litter loss: mammary gland

Postmortem examinations (offspring):

SACRIFICE
- The F1 offspring were sacrificed on PND 5-7

GROSS NECROPSY
-- Gross necropsy consisted of external and internal examinations.

HISTOPATHOLOGY / ORGAN WEIGTHS: not performed

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 (many-to-one t-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 (many-to-one rank 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.
All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance.

Reproductive indices:

The following indices were calculated:
Mating index (%) = 100 x (number of females mated/number of females paired)
Fertility index (%) = 100 x (number of pregnant females/number of females paired)
Conception index (%) = 100 x (number of pregnant females/number of femates mated)
Gestation index (%) = 100 x (number of females bearing live pups/number of pregnant females)
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:

The following indices were calculated:
Post-implantation survival index (%) = 100 x (total number of offspring born/total number of implantation sites)
Post-implantation survival index was expressed as 100% when the number of offspring exceeded the number of implantation sites recorded.
Percentage live males at first check (%) = 100 x (number of live male pups at first litter check/number of live pups at total litter check)
Percentage live females at first check (%) = 100 x (number of live female pups at first litter check/number of live pups at total litter check)
Percentage of postnatal loss (%) = 100 x (number of dead pups before planned necropsy/number of live pups at first litter check)
Viability index (%) = 100 x (number of live offspring on PND 4/number of live offspring on PND 1)

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

No clinical signs of toxicity were noted either during the daily observation for clinical signs or the weekly arena observations.
Salivation seen after dosing among animals of the 300 and 1000 mg/kg bw/day dose groups from the third week of treatment onwards was considered to be a physiological response rather than a sign of systemic toxicity considering the nature and minor severity of the effect and its time of occurrence (i.e. after dosing).
Incidental findings that were noted included rales, chromodacryorrhoea (snout), alopecia and scabbing, all at a slight degree. These findings 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. At the incidence observed, these were not considered to be signs of toxicological relevance.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

No mortality occurred during the study period that was considered to be related to treatment with the test item.
One female in the 300 mg/kg bw/day group had delivered one dead (male) fetus only. Due to this total litter loss she was euthanized two days thereafter. Histopathology of the reproductive organs of this female and the male she was mated with did not reveal any changes that could explain this total litter loss. As it was an isolated finding at the mid dose level, it was considered to be unrelated to treatment with the test item.
One control female was euthanized on Day 24 post-coitum due to complications during parturition. Signs of delivery were noted the day before. At necropsy, she had a pale appearance. In her uterus 14 dead fetuses (9 male and 5 female) were found next to reddish content. As far as their autolytic condition permitted external examination, no abnormalities were noted. The female showed marked hepatocellular necrosis in the liver (corresponding macroscopic finding: liver with many, reddish foci) which was considered to be related to the intrauterine dead of the fetuses and the cause of moribundity of this animal. Furthermore she had a gelatinous thymus (corresponding microscopic finding: marked lymphocytolysis). As this control female was treated with the vehicle alone a relation to treatment with the test item could be excluded.
All remaining animals survived until their scheduled necropsies.

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.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Food consumption before or after allowance for body weight was similar between treated and control animals.

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):

Haematological parameters of treated rats were not considered to be affected by treatment. The slightly, but statistically significantly, lower activated partial thromboplastin time (APPT) time recorded in males at 300 mg/kg bw/day was not considered to be test item-related as this change occurred in the absence of a treatment-related distribution and remained within the range considered normal for rats of this age and strain.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no differences noted between control and treated rats that were considered to be test item-related.
The slightly, but statistically significantly, higher concentration of glucose and lower concentration of chloride recorded in females at 100 mg/kg bw/day and 300 mg/kg bw/day, respectively, was not considered to be test item-related as this change occurred in the absence of a treatment-related distribution and remained within the range considered normal for rats of this age and strain.

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

Hearing ability, pupillary reflex, static righting reflex and grip strength were normal in all selected animals.
The variation in motor activity did not indicate a relation with treatment. All groups showed a similar habituation profile with very high activity in the first interval that decreased over the duration of the test period.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

There were no test item-related microscopic observations.

Histopathological findings: neoplastic:

not examined

Other effects:

no effects observed

Reproductive function: oestrous cycle:

not examined

Reproductive function: sperm measures:

no effects observed

Description (incidence and severity):

No treatment-related toxicologically significant changes were noted on spermatogenic profiling and histopathological examination of male reproductive organs. No further measurements were performed.

Reproductive performance:

no effects observed

Description (incidence and severity):

All females of the control and treated groups showed evidence of mating. Mating index was 100% for all groups.
Fertility and conception index were not affected by treatment. All paired and mated females were pregnant, except for one female each in the 100 and 1000 mg/kg bw/day group. Only for the high dose female abnormalities in the cervix were noted which could explain that this female was not pregnant. Histopathology of this female showed a massive luminal dilation in the cervix. This finding was considered to be incidental. In the absence of a dose-related distribution, the two non-pregnancies were considered to be unrelated to treatment. Histopathology of the mammary gland of the female at 300 mg/kg bw/day with total litter loss did not reveal any changes that could explain the lack of delivery of healthy pups.
Precoital time was not affected by treatment. All females were mated within the first 4 days, except for one female each in the control and 100 mg/kg bw/day groups for which it took 12 days before they showed evidence of mating. In the absence of a dose-related trend, this finding was not considered to be caused by the test item.
Gestation index and duration of gestation were unaffected by treatment. All pregnant females delivered living pups between Days 21 and 22 post-coitum, except for one control female which was euthanized on Day 24 post-coitum due to complications during parturition.
The number of corpora lutea and implantation sites was considered to be unaffected by treatment. One female at 300 mg/kg bw/day and one female at 1000 mg/kg bw/day had respectively one and two implantations only. Such low numbers of implantations are occasionally seen for rats in this age. In the absence of a dose-related trend no toxicological significance was attached to this observation.
For one female at 300 mg/kg bw/day, the number of implantations was slightly higher than the number of pups. This was considered to be due to normal resorption of these areas as these enumerations were performed on Day 6 of lactation.

Key result

Dose descriptor:

NOAEL

Remarks:

general toxicity

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects at the highest tested dose of 1000 mg/kg bw/day

Key result

Dose descriptor:

NOAEL

Remarks:

reproductive toxicity

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects on reproduction at the highest tested dose of 1000 mg/kg bw/day

Key result

Critical effects observed:

no

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

No clinical signs occurred among pups that were considered to be related to treatment. One pup each in the 100 mg/kg bw/day groupand 1000 mg/kg bw/day group were noted with a deformed right hind leg from lactation Day 4 onwards. At the low incidence and in the absence of a dose-related trend, no toxicological relevance was attached to this finding. All remaining clinical signs observed incidentally were within the range considered normal for pups of this age, and were therefore considered to be unrelated to treatment.

Mortality / viability:

mortality observed, non-treatment-related

Description (incidence and severity):

The total number of offspring born compared to the total number of uterine implantations was not considered to be affected by treatment.
Two out of the three pups in the control group that were found dead at first litter check, came from the same litter in which also one pup was found dead on lactation Day 2 and one pup was found missing on lactation Day 3. In addition, two pups in the 300 mg/kg bw/day group and one pup in the 1000 mg/kg bw/day group were found dead at first litter check, and one pup in the 100 mg/kg bw/day group was found missing on lactation Day 4. 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.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

Body weights of pups were not affected by treatment up to and including 1000 mg/kg bw/day.

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

not examined

Clinical biochemistry findings:

not examined

Urinalysis findings:

not examined

Sexual maturation:

not examined

Organ weight findings including organ / body weight ratios:

not examined

Gross pathological findings:

effects observed, non-treatment-related

Description (incidence and severity):

No macroscopic findings were noted among pups that were considered to be related to treatment.
Two pups noted with a deformed right hind leg. At the low incidence and in the absence of a dose-related trend, no toxicological relevance was attached to this finding. All remaining clinical signs observed incidentally were within the range considered normal for pups of this age, and were therefore considered to be unrelated to treatment.
All pups found dead, except for one, had no milk in their stomachs. No toxicological relevance was attributed to this observation since it occurred in the absence of a dose-related trend and remained within the range considered normal for pups of this age. The nature and incidence of remaining macroscopic findings were within the range considered normal for pups of this age, and they were therefore considered to be unrelated to treatment.

Histopathological findings:

not examined

Other effects:

no effects observed

Behaviour (functional findings):

not examined

Developmental immunotoxicity:

not examined

Key result

Dose descriptor:

NOAEL

Remarks:

developmental toxicity

Generation:

F1

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects on development at the highest tested dose of 1000 mg/kg bw/day

Key result

Critical effects observed:

no

Key result

Reproductive effects observed:

no

Formulation analysis

The concentrations analysed in the formulations of Group 2, Group 3 and Group 4 were in agreement with target concentrations (i.e. mean accuracies 99%, 101% and 104%, respectively; n = 12 (4 samples at 105, 50% and 90% height of the vessel each), 4 (4 samples at 50% height of the vessel) and 12 ((4 samples at 105, 50% and 90% height of the vessel each), respectively.

The formulations of Group 2 and Group 4 were homogeneous (i.e. coefficient of variation 8.6%, 10% and 7.2% for low, mid- and high-dose groups, respectively).

Conclusions:

In a GLP-compliant OECD guideline 422 study, no adverse effects on reproduction and development were observed at the highest tested dose of 1000 mg/kg bw/day, which was considered a NOAEL for reproductive and developmental toxicity.

Executive summary:

In a GLP-compliant OECD guideline 422 study with rats, groups of 10 animals/sex/dose were treated by gavage with the test substance in corn oil at dose levels of 0 (concurrent vehicle controls), 100, 300 and 1000 mg/kg bw/day. No treatment-related toxicologically significant changes were noted in any of the parental parameters investigated in this study (i.e. viability/mortality, clinical appearance, functional observations, body weight, food consumption, clinical laboratory investigations, macroscopic examination, organ weights, and microscopic examination). Based on this, the highest tested dose level of 1000 mg/kg bw/day was considered to be a NOAEL for general toxicity. No treatment-related toxicologically significant changes were noted at any dose level in any of the reproductive parameters investigated in this study (i.e. mating, fertility and conception indices, precoital time, numbers of corpoa lutea and implantations, spermatogenic profiling, and histopathological examination of reproductive organs). No treatment-related toxicologically significant changes were noted at any dose level in any of the developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy). Based on this, the highest tested dose level of 1000 mg/kg bw/day is considered to be a NOAEL for reproductive and developmental toxicity.

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

Quality of whole database:

1 (GLP-compliant guideline study)

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 a GLP-compliant OECD guideline 422 study with rats, groups of 10 animals/sex/dose were treated by gavage with the test substance in corn oil at dose levels of 0 (concurrent vehicle controls), 100, 300 and 1000 mg/kg bw/day. No treatment-related toxicologically significant changes were noted in any of the parental parameters investigated in this study (i.e. viability/mortality, clinical appearance, functional observations, body weight, food consumption, clinical laboratory investigations, macroscopic examination, organ weights, and microscopic examination). Based on this, the highest tested dose level of 1000 mg/kg bw/day was considered to be a NOAEL for general toxicity. No treatment-related toxicologically significant changes were noted at any dose level in any of the reproductive parameters investigated in this study (i.e. mating, fertility and conception indices, precoital time, numbers of corpoa lutea and implantations, spermatogenic profiling, and histopathological examination of reproductive organs). No treatment-related toxicologically significant changes were noted at any dose level in any of the developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy). Based on this, the highest tested dose level of 1000 mg/kg bw/day is considered to be a NOAEL for reproductive and developmental toxicity.

Effects on developmental toxicity

Description of key information

In a GLP-compliant OECD guideline 422 study with rats, no adverse effects on development were noted at the highest tested dose of 1000 mg/kg bw/day.

Link to relevant study records

Reference

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 September 2016 - 5 December 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

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

Version / remarks:

March 1996

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD Guideline 421, Reproduction/Developmental Toxicity Screening Test

Version / remarks:

July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3650, Combined Repeated Dose Toxicity with the Reproduction/Developmental Toxicity Screening Test

Version / remarks:

July 2000

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EPA OPPTS 870.3550, Reproduction/Developmental Toxicity Screening Test

Version / remarks:

July 2000

Deviations:

no

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material:
In refrigerator (2-8°C)
- Stability at higher temperatures: yes, maximum temperature: 40°C, maximum duration: 20 minutes
- Solubility and stability of the test substance in the solvent/vehicle:
stability in corn oil for at least 6 hours at room temperature, under normal laboratory light conditions is confirmed over the concentration range 1 to 200 mg/mL in a separate study
- Specific gravity 0.977 g/mL at 20 °C
- No correction for purity required


FORM AS APPLIED IN THE TEST (if different from that of starting material)

The test item was heated up to a maximum of 39ºC for a maximum of 23 minutes during the preparation of formulations.

Species:

rat

Strain:

other: Crl:WI(Han)

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source:
Charles River Deutschland, Sulzfeld, Germany
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation:
Approximately 10-11 weeks
- Weight at study initiation:
males 272-321 g, females 179-228 g
- Fasting period before study:
no
- Housing:
Sterilized sawdust as bedding material and paper as cage-enrichment/nesting material were supplied, except during locomotor activity measurements.
Pre-mating: in groups of 5 animals/sex/cage in Macrolon plastic cages MIV type
Mating: on 1:1 basis m:f in MIII type Macrolon cages
Post-mating: males in their home cages with a maximum of 5 animals/cage, females individually in MIII type Macrolon cages
Lactation: pups with the dam in Macrolon MIII type cages, except during locomotor activity monitoring of the dams the pups were kept warm in their home cage using bottles filled with warm water. In order to avoid hypothermia of pups, pups were not left without their dam or a bottle filled with warm water for longer than 30-40 minutes.
Locomotor activity measurements: individually in polycarbonate cages without cage-enrichment, bedding material, food and water.
- Diet: pelleted rodent diet (SM R/M-Z from SSNIFF®), ad libitum, except during locomotor measurements
- Water: tap water, ad libitum, except during locomotor measurements, when animals did not have access to water for a maximum 1 hour and 23 minutes.
- Acclimation period:
At least 5 days prior to start of treatment

DETAILS OF FOOD AND WATER QUALITY:
Diet, water, bedding and cage-enrichment/nesting material evaluation for contaminants and/or nutrients was performed according to facility standard procedures. There were no findings that could interfere with the study.

ENVIRONMENTAL CONDITIONS
(set to maintain)
- Temperature (°C):
18-24
- Humidity (%):
40-70
- Air changes (per hr):
at least 10
- Photoperiod (hrs dark / hrs light):
12/12

IN-LIFE DATES: From: 06 Sepmeber 2016 To: 05 December 2016

Route of administration:

oral: gavage

Details on exposure:

- PREPARATION OF DOSING SOLUTIONS:
Adjustment was made for specific gravity of the vehicle. No correction was made for the purity/composition of the test item.
Formulations (w/w) were prepared daily within 6 hours prior to dosing and were homogenized to a visually acceptable level. The test item was heated up to a maximum of 39 ºC for a maximum of 23 minutes. In order to obtain homogeneity, the test item in vehicle was heated up to a maximum temperature of 42 ºC for a maximum of 35 minutes. The formulations were allowed to cool down to a temperature of maximally 40 ºC prior to dosing.

- VEHICLE
- Justification for use and choice of vehicle:
based on trial formulations performed at Charles River Den Bosch
- Amount of vehicle (if gavage):
5 mL/kg bw
- Specific gravity: 0.92

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Analyses were conducted on a single occasion during the treatment phase according to a validated method. Samples of formulations were analyzed for homogeneity (highest and lowest concentration) and accuracy of preparation (all concentrations).
The accuracy of preparation was considered acceptable if the mean measured concentrations were 90-110% of the target concentration. Homogeneity was demonstrated if the coefficient of variation was ≤ 10%.

Details on mating procedure:

- M/F ratio per cage: 1:1
- Length of cohabitation: maximum 12 days
- Proof of pregnancy: vaginal plug / sperm in vaginal smear referred to as day 0 post-coitum
- After successful mating each pregnant female was caged individually in Macrolon type III cages

Duration of treatment / exposure:

Males: 31 days, i.e. 2 weeks prior to mating, during mating, and up to the day prior to scheduled necropsy.
Females that delivered: 41-52 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 least 4 days after delivery up to and including the day before scheduled necropsy.
Two females that failed to deliver (low- and high-dose groups): 40 and 42 days, respectively

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.

Duration of test:

Males: at least 31 days, females: at least 40 days

Dose / conc.:

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

Remarks:

Concurrent vehicle controls, Group 1

Dose / conc.:

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

Remarks:

Group 2

Dose / conc.:

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

Remarks:

Group 3

Dose / conc.:

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

Remarks:

Group 4

No. of animals per sex per dose:

10/sex/dose

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: based on results of a 10-day dose range finding study

Maternal examinations:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule:
at least twice daily for mortality and viability

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule:
at least once daily from start of treatment onwards up to the day prior to necropsy after dosing at no specific time point, but within a similar time period after dosing for the respective animals. 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.

BODY WEIGHT: Yes
- Time schedule for examinations:
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 and 4. In addition, for the females for which mating was overlooked one additional body weight measurement was performed.

FOOD CONSUMPTION AND COMPOUND INTAKE: yes
- Time schedule for examinations: 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 and 4.


FOOD EFFICIENCY:
no

WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Subjective appraisal was maintained during the study, but no quantitative investigation was introduced, as no treatment related effect was suspected.

POST-MORTEM EXAMINATIONS: Yes
- Females that delivered: PND 5-7
- Females that failed to deliver: Post-coitum Days 25 or 27 (females with evidence of mating).
- Females with total litter loss: Two days after litter loss
- One female euthanized in extremis: day 24 post-coitum
- Organs examined:
The following organ weights were recorded:
Selected 5 animals/sex/group: adrenal glands, brain, heart, kidneys, liver, ovaries, spleen, thymus, thyroid including parathyroid, uterus including cervix.

The following tissues were examined by histopathologist:

On selected 5 animals/sex/group from controls and high-dose group: adrenal glands, brain (cerebellum, mid brain, cortex (7-levels), caecum, cervix, clitoral gland, colon, duodenum, epididymides, eyes with optic nerve, if detectable, and Harderian gland; female mammary gland area, femur including joint, heart, ileum, jejunum, kidneys, liver, lungs, lymph nodes (mandibular, mesenteric), ovaries, Peyers patches (jejunum, ileum) if detectable, pituitary gland, preputial gland, sciatic nerve, skeletal muscle, spinal cord (cervical, midthoracic, lumbar), spleen, sternum with bone marrow, stomach, thymus, thyroid including parathyroid if detectable, trachea, urinary bladder, uterus, vagina, all gross lesions
On the female euthanized in extremis: all preserved organs and tissues
On all females that failed to deliver healthy pups: reproductive organs
On the female with total litter loss: mammary gland

OTHER:
HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the end of the treatment period on the day of scheduled necropsy
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes, overnight for maximum 24 hours; water was available.
- How many animals: selected 5 females/group
- Parameters examined: WBC, differential leucocyte count (neutrophils, lymphocytes, monocytes, eosinophils, basophils), RBC, reticulocytes, RDW, haemoglobin, haematocrit, MCV, MCH, MCHC, platelets; PT, APTT

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the end of the treatment period on the day of scheduled necropsy
- Animals fasted: Yes, overnight for maximum 24 hours; water was available.
- How many animals: selected 5 females/group
- Parameters examined: ALAT, ASAT, ALP, total protein, albumin, total bilirubin, bile acids, urea, creatinine, glucose, cholesterol, sodium, potassium , chloride, calcium, inorganic phosphate

NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: selected males during week 4, selected females towards the end of the scheduled lactation period (from lactation Day 4 onwards)
- Dose groups that were examined: all dose levels, selected 5 animals/sex/group
- Battery of functions tested: sensory activity (hearing, pupillary reflex, static rightling reflex, fore- and hind limb grip strength, motor activity (total movements and ambulations)

Ovaries and uterine content:

The ovaries and uterine content was examined after termination: Yes
Examinations included:
- Gravid uterus weight: no, females were allowed to litter naturally
- Number of corpora lutea: Yes
- Number of implantations: Yes
- Number of early resorptions: No
- Number of late resorptions: No

Fetal examinations:

- External examinations: Yes, all per litter
- Soft tissue examinations: no specific examinations were performed, but gross necropsy with attention paid to abnormalities was conducted on all pups
- Skeletal examinations: no specific examinations were performed, but gross necropsy with attention paid to abnormalities was conducted on all pups
- Head examinations: no specific examinations were performed, but gross necropsy with attention paid to abnormalities was conducted on all pups

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 (many-to-one t-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 (many-to-one rank 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.
All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance.

Indices:

The following indices were calculated:
Post-implantation survival index (%) = 100 x (total number of offspring born/total number of implantation sites)
Post-implantation survival index was expressed as 100% when the number of offspring exceeded the number of implantation sites recorded.
Percentage live males at first check (%) = 100 x (number of live male pups at first litter check/number of live pups at total litter check)
Percentage live females at first check (%) = 100 x (number of live female pups at first litter check/number of live pups at total litter check)
Percentage of postnatal loss (%) = 100 x (number of dead pups before planned necropsy/number of live pups at first litter check)
Viability index (%) = 100 x (number of live offspring on PND 4/number of live offspring on PND 1)

Historical control data:

Available from the same testing laboratory for the study period.

Clinical signs:

effects observed, non-treatment-related

Description (incidence and severity):

No clinical signs of toxicity were noted either during the daily observation for clinical signs or the weekly arena observations.
Salivation seen after dosing among animals of the 300 and 1000 mg/kg bw/day dose groups from the third week of treatment onwards was considered to be a physiological response rather than a sign of systemic toxicity considering the nature and minor severity of the effect and its time of occurrence (i.e. after dosing).
Incidental findings that were noted included rales, chromodacryorrhoea (snout), alopecia and scabbing, all at a slight degree. These findings 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. At the incidence observed, these were not considered to be signs of toxicological relevance.

Mortality:

mortality observed, non-treatment-related

Description (incidence):

No mortality occurred during the study period that was considered to be related to treatment with the test item.
One female in the 300 mg/kg bw/day group had delivered one dead (male) fetus only. Due to this total litter loss she was euthanized two days thereafter. Histopathology of the reproductive organs of this female did not reveal any changes that could explain this total litter loss. As it was an isolated finding at the mid dose level, it was considered to be unrelated to treatment with the test item.
One control female was euthanized on Day 24 post-coitum due to complications during parturition. Signs of delivery were noted the day before. At necropsy, she had a pale appearance. In her uterus 14 dead fetuses (9 male and 5 female) were found next to reddish content. As far as their autolytic condition permitted external examination, no abnormalities were noted. The female showed marked hepatocellular necrosis in the liver (corresponding macroscopic finding: liver with many, reddish foci) which was considered to be related to the intrauterine dead of the fetuses and the cause of moribundity of this animal. Furthermore she had a gelatinous thymus (corresponding microscopic finding: marked lymphocytolysis). As this control female was treated with the vehicle alone a relation to treatment with the test item could be excluded.
All remaining animals survived until their scheduled necropsies.

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.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

Food consumption before or after allowance for body weight was similar between treated and control animals.

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Description (incidence and severity):

Haematological parameters of treated rats were not considered to be affected by treatment.

Clinical biochemistry findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no differences noted between control and treated rats that were considered to be test item-related.
The slightly, but statistically significantly, higher concentration of glucose and lower concentration of chloride recorded in females at 100 mg/kg bw/day and 300 mg/kg bw/day, respectively, was not considered to be test item-related as this change occurred in the absence of a treatment-related distribution and remained within the range considered normal for rats of this age and strain.

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Description (incidence and severity):

Hearing ability, pupillary reflex, static righting reflex and grip strength were normal in all selected animals.
The variation in motor activity did not indicate a relation with treatment. All groups showed a similar habituation profile with very high activity in the first interval that decreased over the duration of the test period.

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, non-treatment-related

Description (incidence and severity):

Organ weights and organ to body weight ratios of treated animals were unaffected by treatment with the test item.
The slightly, but statistically significantly, higher kidney weight (absolute and relative to body weight) recorded in females at 300 mg/kg bw/day was not considered to be test item-related as this change occurred in the absence of a treatment-related distribution and remained within the range considered normal for rats of this age and strain.

Gross pathological findings:

no effects observed

Description (incidence and severity):

Macroscopic observations at necropsy did not reveal any alterations that were considered to have arisen as a result of treatment.
The incidence of all findings among control and treated animals was within the background range of findings that are encountered among rats of this age and strain, and did not show a dose-related incidence trend. These necropsy findings were therefore not considered to be toxicologically relevant.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Description (incidence and severity):

There were no test item-related microscopic observations.

Histopathological findings: neoplastic:

no effects observed

Other effects:

no effects observed

Details on results:

For details on reproductive toxicity see section 7.8.1 of this IUCLID (cross-reference).

Number of abortions:

no effects observed

Description (incidence and severity):

Examination of cage debris of pregnant females revealed no signs of premature birth.

Pre- and post-implantation loss:

no effects observed

Description (incidence and severity):

The total number of offspring born compared to the total number of uterine implantations was not considered to be affected by treatment.

Total litter losses by resorption:

not examined

Early or late resorptions:

not examined

Dead fetuses:

effects observed, non-treatment-related

Description (incidence and severity):

Two out of the three pups in the control group that were found dead at first litter check, came from the same litter in which also one pup was found dead on lactation Day 2 and one pup was found missing on lactation Day 3. In addition, two pups in the 300 mg/kg bw/day group and one pup in the 1000 mg/kg bw/day group were found dead at first litter check, and one pup in the 100 mg/kg bw/day group was found missing on lactation Day 4. 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.

Changes in pregnancy duration:

no effects observed

Description (incidence and severity):

Gestation index and duration of gestation were unaffected by treatment. All pregnant females delivered living pups between Days 21 and 22 post-coitum, except for one control female which was euthanized on Day 24 post-coitum due to complications during parturition. In addition, one female in the 300 mg/kg bw/day group was found with a single dead pup at first litter check on lactation Day 1. Both observations were considered to be unrelated to treatment.

Changes in number of pregnant:

no effects observed

Description (incidence and severity):

All paired and mated females were pregnant, except for one female each in the 100 and 1000 mg/kg bw/day group. Only for the high dose female abnormalities in the cervix were noted which could explain that this female was not pregnant. Histopathology of this female showed a massive luminal dilation in the cervix. This finding was considered to be incidental. In the absence of a dose-related distribution, the two non-pregnancies were considered to be unrelated to treatment.

Other effects:

effects observed, non-treatment-related

Description (incidence and severity):

One control female showed deficiencies in maternal care. In total 4 out of her 11 pups did not survive until scheduled necropsy on lactation Day 5: two pups were found dead at first litter check, one pup was found dead on lactation Day 2 and one pup was found missing on lactation Day 3. This latter missing pup was most likely cannibalised. All three pups found dead had no milk in their stomachs, and the remaining seven pups in this control litter that survived until scheduled necropsy on lactation Day 5 had lower body weights as compared to other control litters with comparable size or even bigger. As it was a litter from the control group a relation to the test item could be excluded.

Key result

Dose descriptor:

NOAEL

Remarks:

maternal toxicity

Effect level:

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

Based on:

test mat.

Basis for effect level:

other: no adverse effects at the highest tested dose of 1000 mg/kg bw/day

Key result

Abnormalities:

no effects observed

Fetal body weight changes:

not examined

Description (incidence and severity):

Fetal body weights were not examined, females were allowed to litter naturally

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

The total number of offspring born compared to the total number of uterine implantations was not considered to be affected by treatment.

Changes in sex ratio:

no effects observed

Description (incidence and severity):

Sex ratio was unaffected by treatment up to and including 1000 mg/kg bw/day.

Changes in litter size and weights:

no effects observed

Description (incidence and severity):

Litter size and body weights of pups were not affected by treatment up to and including 1000 mg/kg bw/day.

Changes in postnatal survival:

no effects observed

Description (incidence and severity):

The viability index was unaffected up to and including dose level of 1000 mg/kg bw/day.

External malformations:

effects observed, non-treatment-related

Description (incidence and severity):

No macroscopic findings were noted among pups that were considered to be related to treatment. One pup each in the 100 mg/kg bw/day group and 1000 mg/kg bw/day group were noted with a deformed right hind leg from lactation Day 4 onwards. At the low incidence and in the absence of a dose-related trend, no toxicological relevance was attached to this finding.

Skeletal malformations:

effects observed, non-treatment-related

Description (incidence and severity):

No specific examinations were performed, but at gross necropsy no macroscopic findings were noted that were considered to be related to treatment. One pup each in the 100 mg/kg bw/day group and 1000 mg/kg bw/day group were noted with a deformed right hind leg from lactation Day 4 onwards. At the low incidence and in the absence of a dose-related trend, no toxicological relevance was attached to this finding.

Visceral malformations:

no effects observed

Description (incidence and severity):

No specific examinations were performed, but at gross necropsy no macroscopic findings were noted that were considered to be related to treatment.

Other effects:

no effects observed

Key result

Dose descriptor:

NOAEL

Remarks:

developmental toxicity

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effect on development at the highest tested dose of 1000 mg/kg bw/day

Key result

Abnormalities:

no effects observed

Key result

Developmental effects observed:

no

Formulation analysis

The concentrations analysed in the formulations of Group 2, Group 3 and Group 4 were in agreement with target concentrations (i.e. mean accuracies 99%, 101% and 104%, respectively; n = 12 (4 samples at 105, 50% and 90% height of the vessel each), 4 (4 samples at 50% height of the vessel) and 12 ((4 samples at 105, 50% and 90% height of the vessel each), respectively.

The formulations of Group 2 and Group 4 were homogeneous (i.e. coefficient of variation 8.6%, 10% and 7.2% for low, mid- and high-dose groups, respectively).

Conclusions:

In a GLP-compliant OECD guideline 422 study, no adverse effects on development were observed at the highest tested dose of 1000 mg/kg bw/day, which was considered a NOAEL for developmental toxicity.

Executive summary:

In a GLP-compliant OECD guideline 422 study with rats, groups of 10 animals/sex/dose were treated by gavage with the test substance in corn oil at dose levels of 0 (concurrent vehicle controls), 100, 300 and 1000 mg/kg bw/day. No treatment-related toxicologically significant changes were noted in any of the parental parameters investigated in this study (i.e. viability/mortality, clinical appearance, functional observations, body weight, food consumption, clinical laboratory investigations, macroscopic examination, organ weights, and microscopic examination). Based on this, the highest tested dose level of 1000 mg/kg bw/day was considered to be a NOAEL for general toxicity. No treatment-related toxicologically significant changes were noted at any dose level in any of the developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy). Based on this, the highest tested dose level of 1000 mg/kg bw/day is considered to be a NOAEL for developmental toxicity.

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

Quality of whole database:

1 (GLP-compliant guideline study)

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

In a GLP-compliant OECD guideline 422 study with rats, groups of 10 animals/sex/dose were treated by gavage with the test substance in corn oil at dose levels of 0 (concurrent vehicle controls), 100, 300 and 1000 mg/kg bw/day. No treatment-related toxicologically significant changes were noted in any of the parental parameters investigated in this study (i.e. viability/mortality, clinical appearance, functional observations, body weight, food consumption, clinical laboratory investigations, macroscopic examination, organ weights, and microscopic examination). Based on this, the highest tested dose level of 1000 mg/kg bw/day was considered to be a NOAEL for general toxicity. No treatment-related toxicologically significant changes were noted at any dose level in any of the developmental parameters investigated in this study (i.e. gestation index and duration, parturition, maternal care and early postnatal pup development consisting of mortality, clinical signs, body weight and macroscopy). Based on this, the highest tested dose level of 1000 mg/kg bw/day is considered to be a NOAEL for developmental toxicity.

Mode of Action Analysis / Human Relevance Framework

No adverse effects on reproduction and development were noted at the highest tested dose of 1000 mg/kg bw/day.

Justification for classification or non-classification

Based on lack of adverse effects on reproduction and development at the highest tested dose of 1000 mg/kg bw/day, classification of oxacycloheptadecan-2 -one for reproductive and developmental toxicity is not warranted under Regulation (EC) 1272/2008.