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Key value for chemical safety assessment

Toxic effect type:
dose-dependent

Effects on fertility

Description of key information

The NOAEL for Reactive Brown 49 in the reproductive/developmental screening study is at least 1000 mg/kg.

Link to relevant study records
Reference
Endpoint:
screening for reproductive / developmental toxicity
Type of information:
experimental study
Adequacy of study:
key study
Study period:
04 October - 26 November 2012
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 421 (Reproduction / Developmental Toxicity Screening Test)
Deviations:
no
Qualifier:
according to guideline
Guideline:
other: The United States EPA Health Effects Test Guidelines, OPPTS 870.3550, Reproduction/Developmental Toxicity Screening Test, July 2000.
Deviations:
no
GLP compliance:
yes
Limit test:
no
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: DER 8107 / BOP 01-12 (Lot: MHC-0016088200)
- Expiration date of the lot/batch: 25 January 2017

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: At room temperature in the dark
- Stability under test conditions: stable
- Purity/composition correction factor required: No
- Volatile No
- pH: 4.6 at concentration of 27.7% (%w/w)
Species:
rat
Strain:
Wistar
Details on species / strain selection:
This species and strain of rat has been recognized as appropriate for reproduction toxicity studies. WIL Research Europe B.V. has 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.
Nulliparous and nonpregnant females and untreated animals were used at initiation of the study.
- Age at study initiation: Approximately 11 weeks.
- Weight at study initiation: mean weight at start of treatment was 325 gr (males) or 211 gr (females).
- Fasting period before study: no
- Housing:
Pre-mating: Animals were housed in groups of 5 animals/sex/cage in Macrolon cages.
Mating: Females were caged together with males on a one-to-one-basis in Macrolon cages.
Post-mating: Males were housed in their home cage with a maximum of 5 animals/cage. Females were individually housed in Macrolon cages. Pups were kept with the dam until termination
General: Sterilised sawdust as bedding material and paper as cage enrichment were supplied.
- Diet: Free access to pelleted rodent diet (SM R/M-Z from SSNIFF® Spezialdiäten GmbH, Soest, Germany).
- Water: Free access to tap water.
- Acclimation period: At least 5 days

ENVIRONMENTAL CONDITIONS
Environmental controls for the animal room were set to maintain 18 to 24 °C, a relative humidity of 40 to 70%, approximately 15 room air changes/h, and a 12-h light/12-h dark cycle.

IN-LIFE DATES
From: 04 October - 26 November 2012
Route of administration:
oral: gavage
Vehicle:
water
Details on exposure:
- Method of formulation: Formulations (w/w) were prepared daily within 5 hours prior to dosing and were homogenized to a visually acceptable level. No adjustment was made for specific gravity/density of the test substance, vehicle, and/or formulation. No correction was made for the purity/composition of the test substance.
- Storage conditions of formulations: At ambient temperature.
- Dose volume: 5 mL/kg body weight. Actual dose volumes were calculated according to the latest body weight.
Details on mating procedure:
- M/F ratio per cage: 1/1 (one female was cohabitated with one male of the same treatment group, avoiding sibling mating).
- Length of cohabitation: A maximum of 14 days was allowed for mating.
- Proof of pregnancy: Detection of mating was confirmed by evidence of sperm in the vaginal lavage and/or by the appearance of an intravaginal copulatory plug. This day was designated Day 0 post-coitum. Once mating had occurred, the males and females were separated. Detection of mating was not confirmed for one animal at 100 mg/kg which did deliver live offspring. The mating date of this animal was estimated at 21 days prior to the actual delivery date. This day was designated Day 0 postcoitum.
- After successful mating each pregnant female was caged individually in Macrolon cages (MIII type, height 18 cm).
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Samples (0.5 mL) were taken using a pipette (a clean pipette tip was used for every group), and were weighed on an analytical balance at 4 decimals precision. During sampling, formulations were placed on a magnetic stirrer. Immediately after sampling (accuracy and homogeneity samples) or after 5 hours at room temperature under normal laboratory light conditions (stability samples), samples were stored on dry ice. Samples remained on dry ice until receipt at ABL, The Netherlands, where samples were stored at ≤-70 °C until analysis. Samples of formulations were analyzed for homogeneity (highest and lowest concentration) and accuracy of preparation (all concentrations). Stability in vehicle over 5 hours at room temperature under normal laboratory light conditions was also determined (highest and lowest concentration). 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%. Formulations were considered stable if the relative difference before and after storage was maximally 10%.
No test substance was detected in the Group 1 formulations. The concentrations analysed in the formulations of Group 2, 3 and 4 were in agreement with target concentrations (i.e. mean accuracies between 90% and 110%). The formulations of Group 2 and 4 were homogeneous (i.e. coefficient of variation ≤ 10%). Formulations at the entire range were stable when stored at room temperature under normal laboratory light conditions for at least 5 hours (i.e. relative difference ≤ 10%). The long term storage samples were stable at ≤-70 °C for at least 20 days.
Duration of treatment / exposure:
Males were exposed for 28 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 41-53 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation. Pups were not dosed directly but could have potentially be exposed to the test substance in utero, via maternal milk or from exposure to maternal urine/faeces.
Frequency of treatment:
Once daily for 7 d/w.
Details on study schedule:
- Age at mating of the animals in the study: Approximately 13 weeks
Dose / conc.:
0 mg/kg bw/day (actual dose received)
Remarks:
Control
Dose / conc.:
100 mg/kg bw/day (actual dose received)
Remarks:
Low dose
Dose / conc.:
300 mg/kg bw/day (actual dose received)
Remarks:
Middle dose
Dose / conc.:
1 000 mg/kg bw/day (actual dose received)
Remarks:
High dose
No. of animals per sex per dose:
10
Control animals:
yes, concurrent vehicle
Details on study design:
- Dose levels were based on a 28-day toxicity study in Wistar rats (RCC Project 706397) in which 50, 200 and 1000 mg/kg were tested. At 1000 mg/kg, treatment-related findings were restricted to microscopical changes in the kidneys (hyaline droplets) for males, stomach (nonglandular stomach erosion associated with inflammation, squamous cell hyperplasia and moderate hyperkeratosis) and lung (interstitial fibrosis associated with pigment-laden alveolar macrophages) for some females. It is probable that these findings were related to the mode of application rather than a direct effect of the test article. All test article-related findings noted at the end of the treatment period were fully reversible during the 14-day recovery period.
- Parturition: The females were allowed to litter normally. Day 1 of lactation was defined as the day when a litter was found completed (i.e. membranes, placentas cleaned up, nest built up and/or feeding of pups started). Females that were littering were left undisturbed.
- Identification of pups: On Day 1 of lactation, all pups were individually identified by means of subcutaneous injection of Indian ink.
Positive control:
no
Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS
- Time schedule: At least twice daily.

DETAILED CLINICAL OBSERVATIONS
- Time schedule: Daily from start of treatment onwards, detailed clinical observations were made in all animals. The time of onset, grade and duration of any observed sign was recorded. Signs were graded for severity.

BODY WEIGHT
- Time schedule for examinations: Males and females were weighed on the first day of exposure and weekly thereafter. Mated females were weighed on Days 0, 4, 7, 11, 14, 17 and 20 post-coitum and during lactation on Days 1 and 4.

FOOD CONSUMPTION
- 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 postcoitum and on Days 1 and 4 of lactation.

FOOD EFFICIENCY
- (average food consumption [per animal per day]/average body weight per cage)x1000

WATER CONSUMPTION
No. Subjective appraisal was maintained during the study, but no quantitative investigation introduced as no effect was suspected.

OPHTHALMOSCOPIC EXAMINATION
No.

HAEMATOLOGY
No.

CLINICAL CHEMISTRY
No.

URINALYSIS
No.

NEUROBEHAVIOURAL EXAMINATION
No.

GENERAL REPRODUCTION DATA
- Male number paired with, mating date, confirmation of pregnancy, and delivery day was recorded.
- Pregnant females were examined to detect signs of difficult or prolonged parturition, and cage debris of these females was examined to detect signs of abortion or premature birth.
- Any deficiencies in maternal care (such as inadequate construction or cleaning of the nest, pups left scattered and cold, physical abuse of pups or apparently inadequate lactation or feeding) were examined.
Oestrous cyclicity (parental animals):
Not determined.
Sperm parameters (parental animals):
Slides of the testes were prepared for histopathological staging of spermatogenesis for all males of the control and high dose group and animals suspected to be infertile.
Litter observations:
PARAMETERS EXAMINED
The following parameters were examined in F1 offspring:
number and sex of pups, stillbirths, live births, postnatal mortality, presence of gross abnomalies, weight gain, physical or behavioural abnormalities.

- Mortality: The numbers of live and dead pups on Day 1 of lactation and daily thereafter were determined. If possible, defects or cause of death were evaluated.
- Clinical signs: At least once daily, detailed clinical observations were made in all animals.
- Body weights: Live pups were weighed on Days 1 and 4 of lactation.
- Sex: Sex was determined for all pups on Days 1 and 4 of lactation (by assessment of the ano-genital distance).

GROSS EXAMINATION OF DEAD PUPS
Yes, if possible, defects or cause of death were evaluated.
Postmortem examinations (parental animals):
GROSS PATHOLOGY:
- All animals were deeply anaesthetised and subsequently exsanguinated. The animals were not deprived of food overnight.
- According to test guidelines

ORGAN WEIGHTS
- All males: Epididymides and testes

HISTOPATHOLOGY:
- According to test guidelines
Postmortem examinations (offspring):
SACRIFICE
Pups surviving to planned termination were killed by decapitation on lactation Days 5 - 7.

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

HISTOPATHOLOGY / ORGAN WEIGHTS
No.
Statistics:
The following statistical methods were used to analyze the data:
- If the variables could be assumed to follow a normal distribution, the Dunnett-test (Ref. 1; 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 (Ref. 2; many-to-one rank test) was applied if the data could not be assumed to follow a normal distribution.
- The Fisher Exact-test (Ref. 3) was applied to frequency data.
All tests were two-sided and in all cases p < 0.05 was accepted as the lowest level of significance. Group means were calculated for continuous data and medians were calculated for discrete data (scores) in the summary tables. Test statistics were calculated on the basis of exact values for means and pooled variances. Individual values, means and standard deviations may have been rounded off
before printing. Therefore, two groups may display the same printed means for a given parameter, yet display different test statistics values.

References:
Ref. 1 Dunnett C.W., A Multiple Comparison Procedure for Comparing Several Treatments with a Control, J. Amer. Stat. Assoc. 50, 1096-1121 (1955).
Ref. 2 Miller R.G., Simultaneous Statistical Inference, Springer Verlag, New York (1981).
Ref. 3 Fisher R.A., Statistical Methods for Research Workers, Oliver and Boyd, Edinburgh (1950).
Reproductive indices:
For each group, the following calculations were performed:
- Mating index: Number of females mated/Number of females paired x 100
- Fertility index: Number of pregnant females/Number of females paired x 100
- Conception index: Number of pregnant females/Number of females mated x 100
- Gestation index: Number of females bearing live pups/Number of pregnant females x 100
- Duration of gestation: Number of days between confirmation of mating and the beginning of parturition
Offspring viability indices:
- Percentage live males at First Litter Check: Number of live male pups at First Litter Check/Number of live pups at First Litter Check x 100
- Percentage live females at First Litter Check: Number of live female pups at First Litter Check/Number of live pups at First Litter Check x 100
- Percentage of postnatal loss Days 0-4 of lactation: Number of dead pups on Day 4 of lactation/Number of live pups at First Litter Check x 100
- Viability index: Number of live pups on Day 4 of lactation / Number of pups born alive x 100
Clinical signs:
no effects observed
Mortality:
no mortality observed
Description (incidence):
During the anaesthesia procedure (just before necropsy) one female (number 52, receiving 100 mg/kg) died by accident. Deaths due to anaesthesia are considered to be of incidental nature.
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
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
Behaviour (functional findings):
not examined
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Histopathological findings: non-neoplastic:
effects observed, treatment-related
Description (incidence and severity):
Treatment-related microscopic findings were noted in the kidneys of rats treated at 1000 mg/kg and consisted of:
- the presence of hyaline droplets at minimal (8/10) to slight degree (2/10) in males. The hyaline droplets were considered to represent alpha2μglobulin, a normal protein in male rats which undergoes re-absorption in the proximal cortical tubules. A range of chemicals are known to increase hyaline droplet formation. This protein is not present in higher mammals, including man.
As the presence of hyaline droplets was not accompanied by degenerative tubular alterations this finding was considered to be a non-adverse finding.
- the presence of intracellular tubular (red)brown pigment in 10/10 males (minimal) and 7/7 females (up to moderate). This was not accompanied by other indicators of kidney pathology.
The remainder of the microscopic findings recorded were within the normal range of background pathology encountered in Wistar Han rats of this age and strain.
Other effects:
no effects observed
Reproductive function: oestrous cycle:
not examined
Reproductive function: sperm measures:
no effects observed
Reproductive performance:
no effects observed
MORTALITY
No mortality occurred during the study period. During the anaesthesia procedure (just before necropsy) one female receiving 100 mg/kg died by accident. Deaths due to anaesthesia are considered to be of incidental nature.

CLINICAL SIGNS
No clinical signs of toxicity related to test substance treatment were noted during the observation period. Dark faeces noted for all animals treated at 1000 mg/kg was considered due to the staining properties of the test substance (black), and not regarded toxicologically relevant. Alopecia was noted for two females. This 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 considered signs of no toxicological relevance.

BODY WEIGHTS
Body weights and body weight gain of treated animals remained in the same range as controls over the treatment period.

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

MACROSCOPIC EXAMINATION
All males at 300 mg/kg and all animals at 1000 mg/kg showed discolouration (reddish, dark red, purple or black) of the skin, testes, kidneys, epididymides, and/or spleen. One male treated at 100 mg/kg showed both testes and epididymides reduced in size. This was confirmed at organ weight determination and at microscopic examination. The incidence of other incidental 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 considered to be of no toxicological relevance, and included pelvic dilation of the kidneys, nodule at the epididymides or clitoral glands, focus at the preputial glands, enlarged preputial glands or epididymides, preputial glands reduced in size, diaphragmatic hernia of the liver and alopecia.

Due to the fatty characteristics of the test substance, the discolorations in the epididymides, testes, spleen and skin(subcutis) were most likely to be present in adipose tissue. The discolourations disappeared during the histology staining process and therefore could not be microscopically
correlated. Recorded microscopic findings in these organs were considered not to be treatment related. Because of these reasons, the macroscopic discolouration of these organs were not considered to be toxicologically adverse.

ORGAN WEIGHTS
No toxicologically relevant changes were noted for testes and epididymides weights and terminal body weights of treated males when compared to controls. One male treated at 100 mg/kg showed a reduced weight of the testes and epididymides, which was confirmed at macroscopic and microscopic examination. The statistically significant change noted for epididymides weight at 300 mg/kg was not considered toxicologically relevant as all individual values were within the normal range and no dose response relationship was noted.

REPRODUCTIVE DATA
There were two couples treated at 100 mg/kg, three couples treated at 300 mg/kg and two couples treated at 1000 mg/kg that failed to sire or deliver healthy offspring and were therefore selected for histopathological examination of the reproductive organs. For male no. 20 the cause of infertility consisted of marked seminiferous atrophy with absence of elongating spermatids in the testes and massive oligospermia in the epididymides and testes. Based on the absence of these specific findings or treatment–related findings in the remaining rats, these findings were considered to be within background. Spermatogenic staging profiles were normal for all males examined, besides one male at 100 mg/kg. The females that were not pregnant all had a histologically normal cycling female reproductive tract.
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects
Critical effects observed:
no
Clinical signs:
no effects observed
Mortality / viability:
no mortality observed
Body weight and weight changes:
no effects observed
Sexual maturation:
not examined
Organ weight findings including organ / body weight ratios:
not examined
Gross pathological findings:
no effects observed
Histopathological findings:
not examined
DEVELOPMENTAL DATA
No toxicologically relevant effects on gestation index and duration, parturition, maternal care and early postnatal pup development (mortality, clinical signs, body weight and macroscopy) were observed.

MORTALITY PUPS
Two pups of the control group, three pups at 300 mg/kg and four pups at 1000 mg/kg were found dead or missing during the first days of lactation. Pups missing were most likely cannibalised. No toxicological relevance was attributed to these dead/missing pups since the mortality incidences remained within the range considered normal for pups of this age.

OBSERVATIONS
At first litter check, one pup of the control group showed a pale appearance and missing tail and right hindleg. This pup was missing on Day 3 of lactation. As it concerned a control pup it was not treatment related. Incidental findings consisted of blue spot on the nose or abdomen, a wound on the back, scabbing of the back or nose. For the two pups that were found dead at first litter check absence of milk in the stomach was noted at macroscopic examination. The nature and incidence of these findings remained within the range considered normal for pups of this age, and were therefore considered to be of no toxicological relevance.
Dose descriptor:
NOAEL
Generation:
F1
Effect level:
>= 1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects
Critical effects observed:
no
Reproductive effects observed:
no
Conclusions:
A reproduction and developmental no observed adverse effect level (NOAEL) of greater than 1000 mg/kg was derived.
Executive summary:

The reproduction/developmental toxicity screening test of Reactive Brown 49 in rats by oral gavage was carried out as per OECD 421 and OPPTS 870.3550 guideline. Post acclimatization, four groups of ten male and ten female Wistar rats were exposed by oral gavage to the test substance at 0, 100, 300 and 1000 mg/kg bw/day. Males were exposed for 28 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 41-53 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation. The observations and examinations were evaluated were mortality / viability, clinical signs (daily), body weight and food consumption (at least at weekly intervals), macroscopy at termination, organ weights and histopathology on a selection of tissues, and reproduction/developmental parameters, consisting of mating, fertility and conception indices, precoital time, number of corpora lutea and implantation sites, gestation index and duration, parturition, maternal care, sex ratio and early postnatal pup development (mortality, clinical signs, body weights and macroscopy). Formulations were analyzed once during the study to assess accuracy, homogeneity and stability.

There were treatment-related macroscopic findings at 300 and 1000 mg/kg bw/day, which consisted of reddish, dark red, purple or black discoloration of the testes, epididymides, skin(subcutis), spleen, and/or kidneys. This is attributed to the staining effect of the test substance and not an adverse effect.

There were treatment-related microscopic findings in the kidneys of all rats treated at 1000 mg/kg consisting of minimal to moderate intracellular tubular (red)brown pigment, correlated to the discoloration noted in the kidneys. This was not accompanied by indicators of kidney pathology.

No reproduction or developmental toxicity was observed up to the highest dose level tested.

In conclusion, based on the absence of functional or morphological disturbances supporting the changes noted in the kidneys for this duration of treatment (males 28 days and females 41-53 days), the parental NOAEL was at least 1000 mg/kg bw/day. In addition, a reproduction and developmental NOAEL of at least 1000 mg/kg bw/day was derived.

 

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:
Study carried out as per OECD 421 guideline and in GLP compliance
Effect on fertility: via inhalation route
Endpoint conclusion:
no study available
Effect on fertility: via dermal route
Endpoint conclusion:
no study available
Additional information

The reproduction/developmental toxicity screening test of Reactive Brown 49 in rats by oral gavage was carried out as per OECD 421 and OPPTS 870.3550 guideline. Post acclimatization, four groups of ten male and ten female Wistar rats were exposed by oral gavage to the test substance at 0, 100, 300 and 1000 mg/kg bw/day. Males were exposed for 28 days, i.e. 2 weeks prior to mating, during mating, and up to termination. Females were exposed for 41-53 days, i.e. during 2 weeks prior to mating, during mating, during post-coitum, and during at least 4 days of lactation. The observations and examinations were evaluated were mortality / viability, clinical signs (daily), body weight and food consumption (at least at weekly intervals), macroscopy at termination, organ weights and histopathology on a selection of tissues, and reproduction/developmental parameters, consisting of mating, fertility and conception indices, precoital time, number of corpora lutea and implantation sites, gestation index and duration, parturition, maternal care, sex ratio and early postnatal pup development (mortality, clinical signs, body weights and macroscopy). Formulations were analyzed once during the study to assess accuracy, homogeneity and stability.


There were treatment-related macroscopic findings at 300 and 1000 mg/kg bw/day, which consisted of reddish, dark red, purple or black discoloration of the testes, epididymides, skin(subcutis), spleen, and/or kidneys. This is attributed to the staining effect of the test substance and not an adverse effect.


There were treatment-related microscopic findings in the kidneys of all rats treated at 1000 mg/kg consisting of minimal to moderate intracellular tubular (red)brown pigment, correlated to the discoloration noted in the kidneys. This was not accompanied by indicators of kidney pathology.


No reproduction or developmental toxicity was observed up to the highest dose level tested.


In conclusion, based on the absence of functional or morphological disturbances supporting the changes noted in the kidneys for this duration of treatment (males 28 days and females 41-53 days), the parental NOAEL was at least 1000 mg/kg bw/day. In addition, a reproduction and developmental NOAEL of at least 1000 mg/kg bw/day was derived.


 

Effects on developmental toxicity

Description of key information

The reproduction and developmental NOAEL of Reactive Brown is at least 1000 mg/kg

Link to relevant study records

Referenceopen allclose all

Endpoint:
developmental toxicity
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
see attachment section 13

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
see attachment section 13

3. ANALOGUE APPROACH JUSTIFICATION
see attachment section 13

Reason / purpose for cross-reference:
read-across source
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Total litter losses by resorption:
no effects observed
Early or late resorptions:
no effects observed
Dead fetuses:
no effects observed
Changes in number of pregnant:
no effects observed
Details on maternal toxic effects:
Maternal toxic effects:no effects

Details on maternal toxic effects:
black discoloration of feces and blue discoloration of urine due to excretion of dye
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (nominal)
Based on:
test mat.
Remarks on result:
not determinable due to absence of adverse toxic effects
Dose descriptor:
NOEL
Effect level:
1 000 mg/kg bw/day (nominal)
Based on:
test mat.
Remarks on result:
not determinable due to absence of adverse toxic effects
Abnormalities:
no effects observed
Fetal body weight changes:
no effects observed
Reduction in number of live offspring:
no effects observed
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
no effects observed
Changes in postnatal survival:
no effects observed
External malformations:
no effects observed
Skeletal malformations:
no effects observed
Visceral malformations:
no effects observed
Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:no effects

Details on embryotoxic / teratogenic effects:
only minor anomalies or variation within the historical range of spontaneous findings were observed
Dose descriptor:
NOAEL
Effect level:
>= 1 000 mg/kg bw/day (nominal)
Based on:
test mat.
Remarks on result:
not determinable due to absence of adverse toxic effects
Abnormalities:
no effects observed
Developmental effects observed:
no
Conclusions:
No adverse effects were observed after daily administration of 1000 mg/kg/day in dams or their fetuses.
Maternal NOAEL: 1000 mg/kg/day
Fetal NOEL: 1000 mg/kg/day
Executive summary:

In this limit test, the test substance, dissolved in distilled water, was administered orally by stomach tube in a single daily dose of 1000 mg/kg body weight to a group of 20 pregnant female Wistar rats from the 7th - 16th day of pregnancy. A simultaneous control group of the same size received the vehicle without test compound. On the 21st day of pregnancy, the dams were killed and delivered by caesarean section. The foetuses delivered by caesarean section were then examined morphologically for developmental disorders.

The study showed that the repeated oral administration of the test substance, at a dose of 1000 mg/kg body weight in the sensitive phase of organogenesis for the conceptuses, did not lead to any impairment of the general physical condition of the dams or impaired intrauterine development of conceptuses.

The morphological examination of the foetuses with regard to stage of development, outwardly detectable anomalies as well as anomalies of the internal organs and the skeleton showed no indication of an embryotoxic or teratogenic effect of the compound. The findings observed are to be regarded as spontaneous in origin.

On the basis of the results of this limit test, the “no observed adverse effect level” in rats following oral administration lies at 1000 mg/kg body weight with regard to maternal and embryofoetal toxicity and teratogenicity.

Endpoint:
developmental toxicity
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Justification for type of information:
REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
see attachment section 13

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
see attachment section 13

3. ANALOGUE APPROACH JUSTIFICATION
see attachment section 13
Reason / purpose for cross-reference:
read-across source
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: The test substance was suitable for oral (by gavage) administration when suspended in distilled water. The test substance was administered at appropriate concentrations prepared with the vehicle. The formulations of each concentration were used for the treatment within 60 minutes after preparation.

VEHICLE: distilled water
Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
no effects observed
Food consumption and compound intake (if feeding study):
no effects observed
Food efficiency:
not examined
Water consumption and compound intake (if drinking water study):
not examined
Ophthalmological findings:
no effects observed
Haematological findings:
no effects observed
Clinical biochemistry findings:
no effects observed
Urinalysis findings:
not examined
Behaviour (functional findings):
no effects observed
Immunological findings:
not examined
Organ weight findings including organ / body weight ratios:
no effects observed
Gross pathological findings:
effects observed, treatment-related
Description (incidence and severity):
At necropsy, findings of slightly pale areas on the liver was recorded for the dams with a statistical significance in the 1000 mg/kg bw/day dose group.
Neuropathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
no effects observed
Other effects:
not specified
Number of abortions:
no effects observed
Pre- and post-implantation loss:
no effects observed
Total litter losses by resorption:
no effects observed
Early or late resorptions:
no effects observed
Dead fetuses:
no effects observed
Changes in pregnancy duration:
no effects observed
Changes in number of pregnant:
no effects observed
Other effects:
not specified
Details on maternal toxic effects:
Maternal toxic effects:yes

Details on maternal toxic effects:
At necropsy, findings of slightly pale areas on the liver was recorded for the dams with a statistical significance in the 1000 mg/kg bw/day dose group.
Dose descriptor:
NOEL
Effect level:
250 mg/kg bw/day (actual dose received)
Based on:
test mat.
Basis for effect level:
gross pathology
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Remarks on result:
not determinable due to absence of adverse toxic effects
Abnormalities:
no effects observed
Fetal body weight changes:
no effects observed
Reduction in number of live offspring:
no effects observed
Changes in sex ratio:
no effects observed
Changes in litter size and weights:
no effects observed
Changes in postnatal survival:
no effects observed
External malformations:
effects observed, non-treatment-related
Skeletal malformations:
effects observed, non-treatment-related
Visceral malformations:
no effects observed
Other effects:
no effects observed
Details on embryotoxic / teratogenic effects:
Embryotoxic / teratogenic effects:no effects
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day (actual dose received)
Based on:
test mat.
Sex:
male/female
Remarks on result:
not determinable due to absence of adverse toxic effects
Abnormalities:
no effects observed
Developmental effects observed:
no

Details on maternal observations:

There was no maternal mortality or maternal clinical signs in any group. The test substance had no effect on the body weight, body weight gain, gravid uterine weight, corrected body weight, corrected body weight gain or food consumption of dams.

At necropsy, findings of slightly pale areas on the liver was recorded for the dams with a statistical significance in the 1,000 mg/kg dose group.

Details on foetal observations:

The intrauterine mortality and sex distribution of foetuses were unaffected by the treatment. There was no difference between groups in the number of corpora lutea or implantations. The body weight of foetuses was similar in all experimental groups. Reddish discolouration of the amniotic epithelium was recorded for the majority of the foetuses in the 1,000 mg/kg dose group that suggested that the coloured test substance (or a coloured metabolite) crossed the placenta. Oedematous placentas were found only in the 1,000 mg/kg bw/day dose group, this was attributed to the treatment with the test substance. Three multiple malformed foetuses were found at external examination in the 1,000 mg/kg bw/day dose group. Two of these foetuses were found in one single litter and had visceral multiple malformations. All of the three foetuses had severe skeletal malformations. The malformations were of very low incidence and taking into account the findings from the whole study and historic data, were considered to reflect spontaneous malformations and are not likely to be related to test substance.

Conclusions:
Under the study conditions, the substance was found to have no developmental toxicity / teratogenic effects. The NOAEL for developmental toxicity / teratogenic effects was determined to be 1,000 mg/kg bw/day.
Executive summary:

A study was conducted to assess the developmental toxicity of the test substance according to OECD Guideline 414, in compliance with GLP.

Groups of 22 sperm-positive female rats were treated orally in one control group and three dose levels of 62.5, 250 and 1,000 mg/kg bw/day (5 mL/kg) from Day 5 to Day 19 post-coitum. Rats were examined daily for morbidity and clinical signs. Body weight was recorded on Days 0, 3, 5, 8, 11, 14, 17 and 20 of gestation. Food consumption was determined on Days 0-3, 3-5, 5-8, 8-11, 11-14, 14-17 and 17-20 of gestation. Caesarean section and gross-pathology were performed on Day 20 of pregnancy. Implantations, early and late resorptions, live and dead foetuses in each uterine horn and the number of corpora lutea in each ovary were recorded. Each foetus was weighed and examined for sex and gross external abnormalities. The placentas were examined externally. About half of each litter was subjected to visceral examination and the other half to skeletal examination (with double staining). All abnormalities found during the foetal examinations were recorded.

No maternal mortality or maternal clinical signs were recorded in any group. The test substance had no effect on the body weight, body weight gain, gravid uterine weight, corrected body weight, corrected body weight gain or food consumption of dams. At necropsy, slightly pale areas on the liver were recorded for the dams with a statistical significance in the 1,000 mg/kg bw/day dose group. The intrauterine mortality and sex distribution of foetuses were unaffected by the treatment. There was no difference between groups in the number of corpora lutea or implantations. The body weight of foetuses was similar in all experimental groups. Reddish discolouration of the amniotic epithelium was recorded for the majority of the foetuses in the 1,000 mg/kg dose group, suggesting that the test substance (or a coloured metabolite) crossed the placenta. Oedematous placentas were found only in the 1,000 mg/kg bw/day dose group. This was attributed to treatment with the test substance. Three multiple malformed foetuses were found at external examination in the 1,000 mg/kg bw/day dose group. Two of these foetuses were found in one single litter and had visceral multiple malformations. All of the three foetuses had severe skeletal malformations. The malformations were of very low incidence. Taking into account the findings from the whole study and historic data, they were considered to reflect spontaneous malformations rather than related to test substance exposure.

Under the study conditions, the substance was found to have no developmental toxicity / teratogenic effects. The NOAEL for maternal toxicity and developmental toxicity / teratogenic effects was determined to be 1,000 mg/kg bw/day.

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
Additional information

No teratogenic or developmental effects were noted in two studies on pre-natal development with structural analogues.


The first study was a limit test, where the test substance, dissolved in distilled water, was administered orally by stomach tube in a single daily dose of 1000 mg/kg body weight to a group of 20 pregnant female Wistar rats from the 7th - 16th day of pregnancy. A simultaneous control group of the same size received the vehicle without test compound. On the 21st day of pregnancy, the dams were killed and delivered by caesarean section. The foetuses delivered by caesarean section were then examined morphologically for developmental disorders.


The study showed that the repeated oral administration of the test substance, at a dose of 1000 mg/kg body weight in the sensitive phase of organogenesis for the conceptuses, did not lead to any impairment of the general physical condition of the dams or impaired intrauterine development of conceptuses.


The morphological examination of the foetuses with regard to stage of development, outwardly detectable anomalies as well as anomalies of the internal organs and the skeleton showed no indication of an embryotoxic or teratogenic effect of the compound. The findings observed are to be regarded as spontaneous in origin.


On the basis of the results of this limit test, the “no observed adverse effect level” in rats following oral administration lies at 1000 mg/kg body weight with regard to maternal and embryofoetal toxicity and teratogenicity.


 


 


In the second study, groups of 22 sperm-positive female rats were treated orally in one control group and three dose levels of 62.5, 250 and 1,000 mg/kg bw/day (5 mL/kg) from Day 5 to Day 19 post-coitum. Rats were examined daily for morbidity and clinical signs. Body weight was recorded on Days 0, 3, 5, 8, 11, 14, 17 and 20 of gestation. Food consumption was determined on Days 0-3, 3-5, 5-8, 8-11, 11-14, 14-17 and 17-20 of gestation. Caesarean section and gross-pathology were performed on Day 20 of pregnancy. Implantations, early and late resorptions, live and dead foetuses in each uterine horn and the number of corpora lutea in each ovary were recorded. Each foetus was weighed and examined for sex and gross external abnormalities. The placentas were examined externally. About half of each litter was subjected to visceral examination and the other half to skeletal examination (with double staining). All abnormalities found during the foetal examinations were recorded.


No maternal mortality or maternal clinical signs were recorded in any group. The test substance had no effect on the body weight, body weight gain, gravid uterine weight, corrected body weight, corrected body weight gain or food consumption of dams. At necropsy, slightly pale areas on the liver were recorded for the dams with a statistical significance in the 1,000 mg/kg bw/day dose group. The intrauterine mortality and sex distribution of foetuses were unaffected by the treatment. There was no difference between groups in the number of corpora lutea or implantations. The body weight of foetuses was similar in all experimental groups. Reddish discolouration of the amniotic epithelium was recorded for the majority of the foetuses in the 1,000 mg/kg dose group, suggesting that the test substance (or a coloured metabolite) crossed the placenta. Oedematous placentas were found only in the 1,000 mg/kg bw/day dose group. This was attributed to treatment with the test substance. Three multiple malformed foetuses were found at external examination in the 1,000 mg/kg bw/day dose group. Two of these foetuses were found in one single litter and had visceral multiple malformations. All of the three foetuses had severe skeletal malformations. The malformations were of very low incidence. Taking into account the findings from the whole study and historic data, they were considered to reflect spontaneous malformations rather than related to test substance exposure.


Under the study conditions, the substance was found to have no developmental toxicity / teratogenic effects. The NOAEL for maternal toxicity and developmental toxicity / teratogenic effects was determined to be 1,000 mg/kg bw/day.

Justification for classification or non-classification

In the absence of effects seen on reproductive performance and developmental toxicity, the substance is not classified for reproductive toxicity according to CLP (Regulation EC No 1272/2008) or DSD (Directive 67/548/EEC).

Additional information