Registration Dossier
Registration Dossier
Data platform availability banner - registered substances factsheets
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Diss Factsheets
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: - | CAS number: 2156592-70-8
- Life Cycle description
- Uses advised against
- Endpoint summary
- Appearance / physical state / colour
- Melting point / freezing point
- Boiling point
- Density
- Particle size distribution (Granulometry)
- Vapour pressure
- Partition coefficient
- Water solubility
- Solubility in organic solvents / fat solubility
- Surface tension
- Flash point
- Auto flammability
- Flammability
- Explosiveness
- Oxidising properties
- Oxidation reduction potential
- Stability in organic solvents and identity of relevant degradation products
- Storage stability and reactivity towards container material
- Stability: thermal, sunlight, metals
- pH
- Dissociation constant
- Viscosity
- Additional physico-chemical information
- Additional physico-chemical properties of nanomaterials
- Nanomaterial agglomeration / aggregation
- Nanomaterial crystalline phase
- Nanomaterial crystallite and grain size
- Nanomaterial aspect ratio / shape
- Nanomaterial specific surface area
- Nanomaterial Zeta potential
- Nanomaterial surface chemistry
- Nanomaterial dustiness
- Nanomaterial porosity
- Nanomaterial pour density
- Nanomaterial photocatalytic activity
- Nanomaterial radical formation potential
- Nanomaterial catalytic activity
- Endpoint summary
- Stability
- Biodegradation
- Bioaccumulation
- Transport and distribution
- Environmental data
- Additional information on environmental fate and behaviour
- Ecotoxicological Summary
- Aquatic toxicity
- Endpoint summary
- Short-term toxicity to fish
- Long-term toxicity to fish
- Short-term toxicity to aquatic invertebrates
- Long-term toxicity to aquatic invertebrates
- Toxicity to aquatic algae and cyanobacteria
- Toxicity to aquatic plants other than algae
- Toxicity to microorganisms
- Endocrine disrupter testing in aquatic vertebrates – in vivo
- Toxicity to other aquatic organisms
- Sediment toxicity
- Terrestrial toxicity
- Biological effects monitoring
- Biotransformation and kinetics
- Additional ecotoxological information
- Toxicological Summary
- Toxicokinetics, metabolism and distribution
- Acute Toxicity
- Irritation / corrosion
- Sensitisation
- Repeated dose toxicity
- Genetic toxicity
- Carcinogenicity
- Toxicity to reproduction
- Specific investigations
- Exposure related observations in humans
- Toxic effects on livestock and pets
- Additional toxicological data
Endpoint summary
Administrative data
Key value for chemical safety assessment
Effects on fertility
Description of key information
In a 28-day repeated dose toxicity study (Watzinger 2011), it was found that the BAB had effects on male reproductive organs. This was confirmed with a 90-day repeated dose toxicity study (Gomez, 2014) in combination with specific examinations in male reproductive system (spermiology), normally performed in OECD guideline 416.
In a screening for reproductive toxicity and developmental toxicity (OECD 421), fertility effects were obsreved at the tested High and Ultra High doses. They were considered as test item related adverse effects; in the absence of any signs of maternal toxicity at the time of mating thser appear to be a direct effect on the reproduction system. Threre were no adverse effectts on the F1 offspring clinical signs, physical or sexual development. There were very low number of litters in the Ultra High dose group. The Low and Mid dose groups were unaffected. There were test item related adverse effects on the mean number of pups born and the number of viable pups in the Ultra High dose group; the High dose group was affected to a lesser extent. No test item related macroscopic finding was recorded for F1 pups at necropsy. NOAEL for reproductive effects of the parental generation was considered to be 50 mg/kg bw/day (based on effects on fertility, implantation and pups born). The NOAEL for pup development and survival was considered to be 200 mg/kg bw/day (based on effects on normal post-natal mortality but reduced pup growth). The NOAEL for systemic toxicity of the parental generation was considered to be 200 mg/kg bw/day (based on relatively minor differences in clinical symptoms, body weight gain and food consumption).
Additional information on toxicity reproduction was gathered for a close structural substance, linear alkyl benzenes LAB, in a two-generation reproduction study (Robinson, 1992). This study did evidence effects on the male reproductive system which were at least partly reversible. The conclusion of the study was that no significant effects on fertility were observed for linear alkyl benzenes.
In a read-across hypothesis and justification report, which purpose was to draw up a proposal for a C&L consistent with the characteristics of the target substance, for use and handling and its safety, the information available of the studies conducted with BAB, LAB together with other information from structural analogues of expected similar metabolic behavior has been used to trace a toxicological profile as reliable as possible.
The remaining uncertainty can be addressed by adaptation of the assessment factors for DNEL derivation.
Furthermore, it is important to remind that the target substance is manufactured and processed in systems that reduce direct contact with workers, under strictly controlled conditions (see Section 3 of IUCLID file and exposure assessment in section 9 and 10 of the CSR). Due to the possible hazard, the classification as Repr. Cat. 2 H361 is assigned.
Link to relevant study records
- Endpoint:
- screening for reproductive / developmental toxicity
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- In life phase: 02 February 2021 - 12 April 2021
- 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
- GLP compliance:
- yes (incl. QA statement)
- Limit test:
- no
- Specific details on test material used for the study:
- - Source of test material: Manufacturer
- Purity: 100% (UVCB)
- Substance as produced (no purification, treatmennt, separation, etc.)
- Storage condition: at controlled room temperature (15-25℃, ≤70% relative humidity), protected from humidity and from light (tight closed container). - Species:
- rat
- Strain:
- Sprague-Dawley
- Details on species / strain selection:
- The test system and the number of animals used in the study are in compliance with the relevant OECD No. 421 [1] guideline. The guideline is designed for use with the rat, which is the preferred rodent species for reproduction toxicity testing. Sprague Dawley rat was selected due to experience of the Test Facility with this strain of rat in toxicity and reproduction toxicity studies and its known fertility.
The minimum number of animals will be used, corresponding to the regulatory guidelines being followed, but taking into consideration the scientific reliability of the collected information. - Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, (Address: Sandhofer Weg 7, D-97633, Sulzfeld, Germany)
- Hygienic level: SPF at arrival, standard laboratory conditions during the study Number of groups: 5 groups; one control and 4 test item-treated groups
- Number/sex of animals:
63 male and 66 female rats were used in the acclimatisation/pre-treatment period.
60 male and 60 female rats (12/sex/group) were used for treatment
Animals were originated from different units, to avoid brother/sister mating.
- Age of animals: Young adult rats, 11 weeks old at starting and 13 weeks at mating.
- Females (if applicable) nulliparous and non-pregnant: yes
- Body weight: Males: 399-489 g, females: 223-307 g (at the start of the treatment). The body weights did not exceed ± 20% of the mean weight for each sex at start of treatment.
- Animal Screening: The health status of the animals assigned to study was verified by the clinical Veterinarian. Females will be nulliparous and non-pregnant.
- Environmental Acclimation: Environmental acclimation period for the study was 19 days.
-Selection, Assignment and Disposition of Animals
All adult/parental (P) male and female animals were sorted according to body weight by computer and divided into weight ranges. An equal number of animals from each weight group was randomly assigned to each dose group to ensure that animals of all test groups are as nearly as practicable of a uniform weight.
This process was controlled by the software PROVANTIS v.9, to verify the homogeneity/variability between/within the groups. Males and females were randomised separately to the dose groups on the day of the first treatment (prior to the start of the treatment).
Any unused, spare animals were moved back to the stock colony in the end of the study.
- Housing:
Animal room: 523
Cage type: Type II and/or III polycarbonate
Bedding / nesting: SAFE 3/4-S Hygienic Animal Bedding (Batch numbers: 03027201024 / 03027201208, Expiry dates: 24 October 2023 / 08 December 2023) and SAFE Crinklets Natural material (Batch number: 05072200824, Expiry date: 24 August 2023) (nesting material) produced by J. Rettenmaier & Söhne GmbH+Co.KG (Address: Holzmühle 1, D-73494 Rosenberg, Germany), were used in the study. Details of the bedding and nesting materials were included in the raw data binder and archived.
Housing: Rodents were group-housed, up to 2 animals of the same sex and dose group/cage, with the exception of the mating and gestation, delivery, lactation period, when they were paired* or individually housed (with pups), respectively.
*Note: Males were individually housed after their mating finished until the end of the mating period
Animal Enrichment:
Group housing allowed social interaction. Deep wood sawdust bedding allowed digging and other normal rodent activities. Nesting material allowed normal nesting behaviour. Certified cardboard hiding tubes (GLP Mini Fun Tunnels, Batch number: A/123 LBS (Serving Biotechnology) Ltd, Address: Unit 20, Gatwick Business Park, Kennel Lane, Hookwood, Surrey, RH6 0AH UK) were also provided to the animals, details of the quality were archived with the raw data.
- Diet (e.g. ad libitum): The animals received ssniff® SM R/M “Autoclavable complete diet for rats and mice – breeding and maintenance” (Batch number: 713 70882, Expiry date: 30 April 2021) produced by ssniff Spezialdiäten GmbH (Address: Ferdinand-Gabriel Weg 16, D-59494 Soest, Germany), ad libitum. The supplier provided an analytical certificate for the batch used, which included in the raw data binder and archived.
The food was routinely analysed and was considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
- Water (e.g. ad libitum): Animals received tap water from the municipal supply, as for human consumption from a 500
mL bottle, ad libitum.
Quality control analysis of the water was performed at least once every three months and microbiological assessment was performed monthly, by Veszprém County Institute of State Public Health and Medical Officer Service (Address: H-8200 Veszprém, József Attila u. 36., Hungary). Copies of the relevant Certificates of Analysis are included in the raw data and are archived at the Test Facility.
The water was considered not to contain any contaminants that could reasonably be expected to affect the purpose or integrity of the study.
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19.6-25.9℃ (target range: 19-25℃)
- Humidity (%): 29-65% (target range: 30-70%)
- Light: 12 hours daily, from 6.00 a.m. to 6.00 p.m.
- Ventilation: 15-20 air exchanges/hour
IN-LIFE DATES: From: 02 February 2021 To:12 April 2021 - Route of administration:
- oral: gavage
- Vehicle:
- other: Propylene glycol + 1% Polysorbate
- Details on exposure:
- PREPARATION OF DOSING SOLUTIONS:
----Preparation of Formulations
As agreed with the Sponsor, no correction for purity of the test item was applied during formulation.
The test item was formulated in the selected vehicle (Propylene glycol + 1% Polysorbate) as a visibly stable homogenous solution at the appropriate concentrations according to the dose level and volume selected, in the Pharmacy of the Test Facility.
Formulations were prepared fresh every day prior to administration to animals.
--- Preparation Details
The calculated amount of the test item was weighed into a clean, calibrated glass container and then mixed properly (with magnetic stirring) with the needed amount of vehicle to reach homogeneity by visual observation.
DIET PREPARATION
- Rate of preparation of diet (frequency):
- Mixing appropriate amounts with (Type of food):
- Storage temperature of food:
VEHICLE
Based on the available information provided by the Sponsor as well as results of a trial formulation Propylene glycol + 1% Polysorbate was selected as vehicle for this study in agreement with the Sponsor. Propylene glycol + 1% Polysorbate was considered as being an acceptable vehicle based on the scientific literature and practice of the Test Facility.
The relevant data of the chemicals used for vehicle of the study are shown below. The Certificates of Analysis of the vehicle are included in the study report (Appendix 2).
Details of the used vehicle see below:
Name: Propylene glycol + 1% Polysorbate
Dispense codes: S51017 / S51018 / S51019 / S51020 / S51021 / S51022 / S51023
Expiry Dates: 12 March 2021 / 20 March 2021 / 26 March 2021 / 08 April 2021 / / 15 April 2021 / / 26 April 2021 / / 09 May 2021
Storage condition: Room temperature
Components of the vehicle used in the study:
Name (Synonym): 1,2-Propanediol (Propylene glycol)
Manufacturer: ThermoFisher Scientific
Batch number: 1920944
Expiry dates: 31 March 2023 / 31 May 2023
Storage conditions: Room temperature
Name (Synonym): Polysorbate 80 (Tween 80)
Manufacturer: Sigma-Aldrich
Batch numbers: BCBV5152 / BCCB7399
Expiry dates: 30 June 2022 / 31 May 2024
Storage conditions: Room temperature
Amount of vehicle:
The control group was treated with the vehicle only (Propylene glycol + 1% Polysorbate) at the dose volume of 5 mL/kg bw.
The test item treated groups received the same dose volume (5 mL/kg bw with a dose level of test item ranging from 12.5 mg/kg bw/day to 800 mg/kg bw/day).
ADMINISTRATION OF TEST ITEM
The dosing solutions were administered to the test item or vehicle-treated (control) animals daily, in the morning, 7 days/week, by oral gavage, using a tipped gavage needle attached to a syringe. A constant volume of 5 mL/kg bw was administered to all animals. The actual volume to be administered was calculated and adjusted based on each animal’s most recent body weight.
Dosing of both sexes began after the acclimatisation (5 days) and pre-exposure period (14 more days), and treatment was performed for 2 weeks before mating, during the mating, and was continued up to and including the day before the necropsy.
The first day of dosing of each animal was regarded as Day 0.
Males were dosed for 28 days (14 days pre-mating and 14 days mating/post-mating period), then were euthanized and subjected to necropsy examination.
------Dosing scheme, Male animals:
-- Acclimatisation-(5 days),-Pre-exposure period (14 days)
-- Pre-mating period 14 days
-- Mating/Post-mating period 14 days: Prior to/at necropsy: Sampling for potential thyroid hormone analysis and Necropsy with organ weight determination (Day 28, all males)
Females were dosed for 14 days pre-mating, for up to 6 days mating period, through gestation and up to and including the day before necropsy (at least 13 days post-partum dosing). The day of birth (when parturition is complete) was defined as Day 0 post-partum. Females not delivered were sacrificed as practical (on Day 50).
---Dosing scheme, Female animals:
-- Acclimatisation (5 days), Pre-exposure period (14 days): Oestrus cycle monitoring during the pre-exposure period
-- Pre-: mating period 14 days: Oestrus cycle monitoring
-- Mating Up to 6 days: Oestrus cycle monitoring
-- Gestation ~22-23 days: -
-- Delivery
-- Lactation periodat lea st 13 days: Pups necropsy (i.e. PND13)
-- PND14: Prior to/at necropsy:
- Sampling for potential thyroid hormone analysis
- Necropsy with organ weight determination (i.e. all females)
All selected F1 offspring were terminated on Post-natal Day (PND) 13 (F1 offspring selected for blood sampling were terminated on PND4 due to technical reasons, to be documented and reported). In order to allow the overnight fasting of dams prior necropsy on PPD14, offspring was euthanized on PPD/PND13, and the dams on PPD/PND14. - Details on mating procedure:
-
Sixty-three male and sixty-six female Sprague Dawley rats were used in the pre-treatment period. At the end of the pre-treatment period, only 60 females majority of them showing regular oestrus cycles and 60 males were allocated to treatment groups (12 animals/sex/groups, 5 groups). Animals were assigned to groups before the start of the treatment as follows:
Group No. Group Designation Dose level (mg/kg bw/day) Concentration of formulation (mg/mL) Dose volume (mL/kg bw) Animal numbers
Males Females
1 Control - - 5 12 12
2 Low Dose 12.5 2.5 5 12 12
3 Mid Dose 50 10 5 12 12
4 Dose 200 40 5 12 12
5 Ultra-High Dose 800 160 5 12 12
The control group was treated with the vehicle only (Propylene glycol + 1% Polysorbate) at the dose volume of 5 mL/kg bw.
Any spare animals were moved to the spare colony of the Test Facility.
Mating procedure
Mating began after the animals had attained full sexual maturity, 2 weeks after the initiation of treatment, with one female and one male of the same dose group (1:1 mating) in a single cage. Females remained with the same male until copulation occurs, for up to 6 days. A vaginal smear was prepared daily during the mating period and stained with 1% (w/v) aqueous methylene blue solution. The smear was examined with a light microscope, the presence of vaginal plug or sperm in the vaginal smear was considered as evidence of copulation (Day 0 of pregnancy as defined by the relevant guidelines). Sperm positive females were caged individually. - Analytical verification of doses or concentrations:
- yes
- Details on analytical verification of doses or concentrations:
- Test item was formulated in the selected vehile (Propylene glycol+ 1% Polysorbate) as a visible stable homogenous solution.
Concentration and homogeneity of the dose formulations were determined three times during the study. On each sampling occasion, top, middle and bottom duplicate samples were taken from test item formulations for concentration and homogeneity measurement, one set to analyse (which was collected in replicates as practical) and one set as a back-up, if required for any confirmatory analyses. Similarly, duplicate samples were taken from the middle of the vehicle control formulation for concentration measurement.
Formulations were prepared daily. No test item was detected in the negative (vehicle) control sample.
Additional sample was collected for confirmatory purposes in case of the Mid dose formulation
After the analytical sampling, the collected formulation samples were stored at room temperature until measurement.
All test item formulations were shown to be homogeneous and they were found to be in the range of 93 to 106% of nominal concentrations.
Based on these results, the formulations were considered suitable for the study purposes.
See table 1 Analytical Results in "any other information on materials and methods incl. tables" chapter - Duration of treatment / exposure:
- Males were dosed for 28 days (14 days pre-mating and 14 days mating/post-mating period).
Females were dosed for 14 days pre-mating, for up to 6 days mating period, through gestation and up to and including the day before necropsy (at least 13 days post-partum dosing). The day of birth (when parturition is complete) was defined as Day 0 post-partum. - Frequency of treatment:
- Daily in the morning, 7 days/week
- Details on study schedule:
- - F1 parental animals not mated until [...] weeks after selected from the F1 litters.
- Selection of parents from F1 generation when pups were [...] days of age.
- Age at mating of the mated animals in the study: [...] weeks - Dose / conc.:
- 0 mg/kg bw/day
- Remarks:
- Control
- Dose / conc.:
- 12.5 mg/kg bw/day
- Remarks:
- Low Dose
- Dose / conc.:
- 50 mg/kg bw/day
- Remarks:
- Mid Dose
- Dose / conc.:
- 200 mg/kg bw/day
- Remarks:
- High Dose
- Dose / conc.:
- 800 mg/kg bw/day
- Remarks:
- Ultra-High Dose
- No. of animals per sex per dose:
- 12 Males
12 Females - Control animals:
- yes, concurrent vehicle
- Details on study design:
- The dose levels were selected based on the results of an OECD 407 study (CIT/Study No. 36887 TSR) and 90 days toxicity test (FR - 11995.307.001.13), with the aim of inducing toxic effects but ideally no death or suffering at the highest dose and a NOAEL at the lowest dose.
In the 28 day study, hypersalivation was recorded with slightly lower body weights, with clearly adverse effects on clinical pathology in the 800 and 400 mg/kg bw/day dose groups. Macroscopic findings were observed in the liver, adrenals, prostate, seminal vesicles, ovaries, thymus, spleen. These changes correlated with treatment-related microscopic observations in the liver (hepatocellular hypertrophy), forestomach (hyperplasia and hyperkeratosis), adrenals (cortical hypertrophy) and kidneys (tubular mineralization in males). Atrophic changes were seen in the prostate, seminal vesicles, testes and thymus (males only).
In the 90 days toxicity test the test item was administered in diet at dose levels of 300, 100 and 3000 ppm. There were test item related effects on food consumption, body weight and body weight gain in the High dose group. Microscopic changes were observed in testis and epididymis in treated males, in liver in females and in kidneys, thymus and spleen in both sexes. Statistically significant higher frequencies of all types of spermatozoid abnormalities were observed in the High dose group. No NOAEL could be identified because significant adverse effects were observed on sperm at 300 ppm.
Based on these data, 800 mg/kg bw/day was chosen as High dose level in this study. Lower doses were spaced with a factor of 4. - Positive control:
- No
- Parental animals: Observations and examinations:
- - Mortality/Morbidity Checks
Animals were inspected for signs of morbidity and mortality twice per day during the treatment (at the beginning and end of each working day) and once a day before the treatment period.
The principles and criteria summarized in the OECD Humane Endpoints Guidance Document No. 19 was taken into consideration [5].
- Clinical Observations
Any clinical sign noted during dosing or at any other occasions was recorded at the time seen.
- Cage Side Observations
General clinical observations were made once a day*, during the pre-treatment and treatment period in the afternoon (pm).
*Note: No general clinical observations were made on the day of necropsy.
- Detailed Clinical Observations
Detailed clinical observations were made before the first day of treatment and then once a week. These observations were made outside the home cage in a standard arena, at similar times as practical. Signs evaluated included changes in skin, fur, eyes, mucous membranes, occurrence of secretions and excretions, and autonomic activity (e.g. lachrymation, piloerection, pupil size and unusual respiratory pattern). Changes in gait, posture and response to handling as well as the presence of clonic or tonic movements, stereotypies (e.g. excessive grooming, repetitive circling), difficult or prolonged parturition or bizarre behaviour (e.g. self- mutilation, walking backwards) were also recorded. Special attention was directed towards the observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma.
Pertinent behavioural changes, signs of difficult or prolonged parturition and all signs of toxicity including mortality was recorded including onset, degree and duration of signs as applicable.
On Gestation Day 13 and/or 14 the sperm positive females were examined for the presence of vaginal bleeding or “placental sign” (intrauterine extravasation of blood as an early sign of pregnancy in rat).
Furthermore, mated females were examined carefully around the time of expected delivery for any signs of difficult or prolonged parturition.
- Body Weights
All male animals were weighed with accuracy of 1 g on the first day of dosing then once a week and at termination or death.
All female animals were weighed with accuracy of 1 g on the first day of dosing then once a week until mating. Parent females were weighed on Gestation Day (GD) 0, 3, 7, 14, 17 and 20, on PPD (Post-partum Day) 0, 4, 7, 10 and 13, and at termination.
Non-pregnant females were weighed with accuracy of 1 g at least once a week until sacrifice.
- Food Consumption
Animal food consumption was determined by weighing the non-consumed diet with a precision of 1 g weekly until the start of the pairing period (on a body weight measurements day). No food consumption was measured during mating. Food consumption was measured on Gestation Day (GD) 0, 3, 7, 10, 14, 17 and 20, on PPD (Post-partum Day) 0, 4, 7, 10 and 13.
Main daily food consumption was calculated for each interval.
- Water Consumption
No water consumption was measured in the study.
- Ophthalmic Examinations
No ophthalmoscopy was measured in the study. - Oestrous cyclicity (parental animals):
- Oestrus cycles was monitored by vaginal smears daily during pre-dosing (12 females/group for 2 weeks) and also checking daily from the beginning of the treatment period until evidence of mating.
Mating began after the animals had attained full sexual maturity, 2 weeks after the initiation of treatment, with one female and one male of the same dose group (1:1 mating) in a single cage. Females remained with the same male until copulation occurs, for up to 6 days. A vaginal smear was prepared daily during the mating period and stained with 1% (w/v) aqueous methylene blue solution. The smear was examined with a light microscope, the presence of vaginal plug or sperm in the vaginal smear was considered as evidence of copulation (Day 0 of pregnancy as defined by the relevant guidelines). Sperm positive females were caged individually.
Additionally, vaginal smears were prepared and examined for each surviving female on the day of necropsy (PPD14) to determine the stage of oestrus cycle and allow correlation with histopathology of the reproductive organs (if necessary).
PRE-EXPOSURE PERIOD:
Each female selected for the study showed acceptable cycles (mean cycle length of 3.92-4.15 days was observed in the different groups) before starting the treatment period
EXPOSURE PERIOD (pre-mating and mating periods):
No indication of test item related effect was seen in the oestrus cycle data during the pre-mating and mating periods (mean cycle length was 4.00, 4.03, 4.08, 4.13 and 4.23 days in the Control, Low, Mid, High and Ultra-High dose groups, respectively).
Prolonged oestrus was recorded for one (1/12) High and three (3/12) Ultra-High dose females. The incidence in the Ultra High dose was considered as being a test item related effect.
Prolonged dioestrus was noted for one Low dose female, one Mid dose female and four Ultra High dose females.
Pseudo-pregnancy was noted for 1, 2, 3 and 2 in Low, Mid, High and Ultra-High dose females. - Sperm parameters (parental animals):
- Parameters examined in male parental generations:
testis weight, epididymis weight, levator ani plus bulbocavernosus muscle complex weight, Cowper's glands and glans penis weight.
daily sperm production, sperm count in testes, sperm count in epididymides, enumeration of cauda epididymal sperm reserve, sperm motility, sperm morphology, other:] - Litter observations:
- Observation of the delivery process, offspring and nursing instinct
Females were allowed to litter and rear their offspring. Delivery process was observed as carefully as possible. All observations were recorded. Any evidence of abnormal deliveries was recorded. The duration of gestation was recorded and was calculated from Day 0 of pregnancy.
Dams were observed to record whether they form a nest from the bedding material provided and cover their new-borns or not. The efficiency of suckling was observed by the presence of milk in the pups' stomach. All observations were recorded.
Each litter was examined as soon as possible after delivery to establish the number and sex of pups, stillbirths, live births, runts (pups that are significantly smaller than normal pups) and the presence of gross abnormalities. Observations were reported individually for each adult animal. In addition to the observations on parent animals, any abnormal behaviour of the offspring was recorded.
Live pups were counted, sexed, weighed individually within 24 hours of parturition (PND 0) and on PND 4 and PND 13, with accuracy of 0.01 g.
All the litters were checked and recorded daily for the number of viable, dead / autolysed and cannibalized pups; clinical signs and any abnormal behaviour or appearance of the pups (external abnormalities) was also recorded on each day. The pups found dead and intact (not cannibalized) were subjected to necropsy with macroscopic examination and the cause of death was identified if possible. All observed abnormalities were recorded.
On PND 4, litters were culled to yield, as nearly as possible, 5 males and 5 females per litter. Pups to be culled within each litter was selected randomly. In litters of insufficient size where the number of males or female pups was less than 5, adjustment of the selection process was made to assure 10 pups are retained. Culling was not performed on litter sizes less than 10. All culled pups were subjected to necropsy with detailed macroscopic external and internal examination for any abnormalities.
The anogenital distance (AGD) of each pup was measured at the time of the first weighing (PND 0). The anogenital distance was also normalized to a measure of pup size (the cube root of body weight) for statistical analysis if considered appropriate by the Study Director.
One male and one female pup per litter (if possible) were previously selected for culling for blood sampling on PND 4.
Number of nipples/areolae in male pups was recorded on PND 13 (individual records was maintained).
All pups were necropsied on PND 13. Pups were examined for gross lesions (particular attention paid to reproductive development, genitals). - Postmortem examinations (parental animals):
- SACRIFICE:
Females were allowed to litter and rear their offspring and were euthanized at study termination.
GROSS NECROPSY:
Gross necropsy was performed on each adult animal irrespective of the date of death. Terminally (males were euthanized after 28 days of dose administration, females on PND14, unmated females or non-delivered females was euthanised when the first dam sacrificed), animals were sacrificed under anaesthesia by exsanguination; anaesthetic product was diluted for pups’ euthanasia as required.
After exsanguination the external appearance was examined, cranium, thoracic and abdominal cavities was opened and the appearance of the tissues and organs (special attention: reproductive system) were observed macroscopically. Any abnormality was recorded with details of the location, colour, shape and size, as appropriate.
Vaginal smears were prepared and examined for each female on the day of necropsy to determine the stage of oestrus cycle.
The number of implantation sites and of visible corpora lutea was recorded in the females.
Uteri of apparently non-pregnant rats was examined to confirm absence of implantation sites.
For animals found dead, no organ weight measurement was performed, but tissue or organ samples were retained for those animals
For euthanized animals, Weight of selected organs were measured, and selected organs and tissues were retained.
ORGAN WEIGHTS
At the time of termination, body weight and weight of the following organs of all adults males was determined:
• With a precision of 0.01 g: testes, epididymides, levator ani plus bulbocavernosus muscle complex
• With a precision of 0.001 g: Cowper’s glands and glans penis.
Testes and epididymides were weighed individually (paired organ weights as applicable were summarised). Relative organ weight (to body and brain weight) was calculated and reported. Individual and/or paired absolute organ weight were reported for each animal and relative organ weight (to body and brain weight) were calculated and reported. The weight of the brain was measured and the organ was preserved.
TISSUE COLLECTION AND PRESERVATION:
The weighed organs and all organs showing macroscopic lesions of all adult and all pups were preserved (including tissues from equivalent control group animals). The testes and epididymides were retained in modified Davidson’s fixative, all other organs in 10% buffered formalin solution.
For all the males, testes, epididymides, accessory sex organs and gross lesions were retained.
For all the females, ovaries, accessory sex organs and gross lesions (including evident target organs) were retained.
BLOOD SAMPLING for Thyroid Hormone Analysis:
For potential thyroid hormone analysis, blood samples were taken by venepuncture using vena sublingualis into tubes containing K3-EDTA as anticoagulant as follows:
• from all dams and at least two pups per litter on PPD 14 (females) / PND13 (pups),
• from eight non-pregnant adult females at termination,
• from all adult males at termination.
The timing of the blood collection for thyroid hormone determination was as close as possible between animals and at the same time of the day in case of sampling on different days. Timing are documented in the raw data.
Blood samples were kept on ice from sampling until centrifugation (within 30 minutes of collection), then centrifuged rapidly (1600 g / approx. 3000 rpm, 10 minutes, 4°C). The resulting plasma was divided in at least two aliquots (volume target was at least 150 μL for the first aliquot and at least 150 µL for the second aliquot, any remaining sample (if any) was kept as a third aliquot) and stored in an ultra-freezer (-80±10°C) until analysis.
Thyroid hormone analysis was not required by the Sponsor’s Representative.
HISTOLOGY and MICROSCOPIC EVALUATION
No histopathology evaluation was performed.
If no tissue processing and microscopic evaluation was required, retained tissues will be discarded after finalisation of the main study report. - Postmortem examinations (offspring):
- GROSS NECROPSY
Dead pups and pups killed on PND4 and/or PND13 were carefully examined externally for gross abnormalities (especially of reproductive organs). After the external observation, the sex determined at birth was confirmed by observation of the internal reproductive organs.
BLOOD SAMPLING for Thyroid Hormone Analysis:
For potential thyroid hormone analysis, blood samples were taken by decapitation into tubes containing K3-EDTA as anticoagulant as follows:
• from up to two pups per litter on PND4 (females if possible),
The collected pup blood (plasma) samples were pooled by litter.
The timing of the blood collection for thyroid hormone determination was as close as possible between animals and at the same time of the day in case of sampling on different days. Timing are documented in the raw data.
Blood samples were kept on ice from sampling until centrifugation (within 30 minutes of collection), then centrifuged rapidly (1600 g / approx. 3000 rpm, 10 minutes, 4°C). The resulting plasma was divided in at least two aliquots (volume target was at least 150 μL for the first aliquot and at least 150 µL for the second aliquot, any remaining sample (if any) was kept as a third aliquot) and stored in an ultra-freezer (-80±10°C) until analysis.
Thyroid hormone analysis was not required by the Sponsor’s Representative.
HISTOLOGY and MICROSCOPIC EVALUATION
No histopathology evaluation was performed.
If no tissue processing and microscopic evaluation was required, retained tissues will be discarded after finalisation of the main study report.
ANOGENITAL DISTANCE, NIPPLE RETENTION
No test item related effect was observed on anogenital distance or nipple retention during the study
No statistically significant changes in the anogenital distance measured on PND 0 were noted for test item treated male and female pups when litter mean values were compared to control
There was no nipples/areolae presence seen in any of the male pups on PND 13 - Statistics:
- Parental Males
- Body weight and body weight gain
- Food consumption
- Number of fertile pairings
- Number of infertile males
- Male mating index
- Male fertility index
- Organ weights (absolute and relative to the body and brain weights)
Parental Females
- Body weight and body weight gain
- Food consumption
- Number of pregnant females
- Number of sperm positive, but non-pregnant females
- Number of non-mated females
- Female mating index
- Female fertility index
- Gestation index
- Duration of pregnancy (days)
- Number of corpora lutea / dams
- Number of implantations / dams
- Number of dams with live pups on Day 0, 4 and 13
- Pre-implantation mortality
- Intrauterine mortality
- Total mortality (intra and extra uterine mortality)
Offspring
- Mean pup body weight (per pup within the group and per litter) on PND 0, 4 and 13
- Mean pup body weight gain (per litter) between PND 0-4, PND 4-13 and PND 0-13
- Number of live births per litter, and number of viable pups per litter on postnatal Days 0, 4 and 13
- Survival Index of pups on postnatal Days 0, 4 and 13
- Sex ratio % on postnatal Days 0, 4 and 13
- Anogenital distance, nipple retention - Reproductive indices:
- Reproductive Ability Assessment and Indices:
There were test item related adverse effects for the Ultra High dose group with regard to reproductive ability, mating or gestation indices.
The mating index was 100% in all groups (males and females). The fertility index was 100%, 83%, 91%, 92% and 67% in the Control, Low, Mid, High and Ultra High dose groups for males and 100%, 83%, 91%, 92% and 25% in the Control, Low, Mid, High and Ultra High dose females. The gestation index was 100% in all groups (all pregnant animals produced litters).
Eight females in the Ultra High dose group were non pregnant. It was considered as test item related effect.
Test item administration was considered to have no impact on the duration of the mating period. Successful coitus (sperm positive vaginal smears and/or vaginal plugs) occurred within 6 days of pairing (cohabitation). The mean duration of mating was 2.58, 2.83, 3.00, 3.08 and 4.17 days in the Control, Low, Mid, High and Ultra High dose groups, respectively. - Offspring viability indices:
- Index Calculation
Survival Index %
( Number of live pups (at designated time) / Number of pups born) x100
Survival index on PND13 will be calculated from number of pups after culling on PND4 instead of number of pups born.
Pre-implantation mortality %
((Number of Corpora lutea - Number of implantations)/ Number of corpora lutea) x100)
Intrauterine mortality %
((Number of implantations - number of liveborns)/Number of implantations) x100
Total mortality %
((("Number of implantations-Number of viable pups (PND0/4/13)) /Number of implantations) x 100
Sex ratio % (females)
((Number of female pups (PND0/4/13)) /Number of viable pups (PND0/4/13)) x 100
- Clinical signs:
- effects observed, treatment-related
- Description (incidence and severity):
- Decreased activity was observed for 1/12 Ultra High dose females from Day 37 until Day 45 (9 days).
Hunched back was observed for 2/12 Ultra High dose females from Day 11 until Day 48. The maximum longevity of the symptom was 31 days.
Noisy respiration was observed for 1/12 High dose male on Day 9 and from Day 25 to Day 26.
Piloerection was observed in case of 4/12 High dose females from Day 34 until Day 48, for 4/12 High dose males from Day 3 to Day 4, for 4/12 Ultra High dose males on Day 3, Day 4, and from Day 11 to Day 12 and 12/12 Ultra High dose females from Day 3 until Day 48. The maximum longevity of the symptom was 37 days.
Decreased activity, hunched back, noisy respiration and piloerection were considered as test item related effects, the following findings were all considered as background findings.
Red discharge (left eye) was observed for 1/12 Control male from Day 10 to Day 20.
Scar was observed for 1/12 Control from Day 2 to Day 6, for 1/12 Mid dose male from Day 2 to Day 6, for 1/12 High dose male from Day 2 to Day 16, for 1/12 Mid dose female from Day 14 to Day 16 and for 1/12 Ultra High dose females from Day 15 until Day 29.
Wound was observed for 1/12 High dose male from Day 2 to Day 4 and 1/12 Ultra High dose female on Day 14.
Increased salivation was observed for 2/12 High dose female from Day 32 until Day 48 and for 1/12 Ultra High dose female from Day 44 until Day 48.
Alopecia (neck dorsa area) was observed for 1/12 Control female from Day 30 until euthanasia.
Thin fur (right cheek) was observed 1/12 Mid dose female from Day 14 to Day 16. - Dermal irritation (if dermal study):
- not examined
- Mortality:
- mortality observed, non-treatment-related
- Description (incidence):
- One Mid dose female was found dead on Day 14 and one Ultra High dose female was found dead on Day 19. The animal had no clinical signs prior death, the animal had piloerection on Day 3 Based on the necropsy findings, gavage accident was considered as a possible cause of death for both animals.
- Body weight and weight changes:
- effects observed, non-treatment-related
- Description (incidence and severity):
- Statistically significantly decreased body weight was observed during the first week of treatment in the High and Ultra High dose male groups (p<0.05) but the animals had the approximately same growth rate as controls thereafter. The body weight effect was test item related but transient.
Statistically significantly decreased body weight gain was observed in the High (p<0.05) and Ultra High (p<0.01) dose males during the first week.
In females, there was no effect on body weight or gain in the first 14 days of the study. Statistically significantly decreased body weight gain was observed in the High (-26.2%, p<0.01) dose female group during gestation.
Decreased body weight gain (-24.7%) was observed for the Ultra High dose females during gestation without statistical significance (n=3 due to the low pregnancy rate). - Food consumption and compound intake (if feeding study):
- effects observed, treatment-related
- Description (incidence and severity):
- Statistically significant decrease in the food consumption was recorded for the High (p<0.05 and p<0.01) and Ultra High dose (p<0.01) males, Ultra High dose females (p<0.01) from Day 0 to Day 14 and during gestation for High dose females (p<0.01).
Based on the body weight gain and food consumption data, the observed effects for the High and Ultra High dose females during gestation were considered as test item related adverse effect. - 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
- Endocrine findings:
- not examined
- Urinalysis findings:
- not examined
- Behaviour (functional findings):
- effects observed, treatment-related
- Description (incidence and severity):
- Decreased activity was observed for 1/12 Ultra High dose females from Day 37 until Day 45 (9 days).
- Immunological findings:
- not examined
- Organ weight findings including organ / body weight ratios:
- no effects observed
- Histopathological findings: non-neoplastic:
- not examined
- Histopathological findings: neoplastic:
- not examined
- Reproductive function: oestrous cycle:
- effects observed, treatment-related
- Description (incidence and severity):
- Pre-exposure period
Each female selected for the study showed acceptable cycles (mean cycle length of 3.92-4.15 days was observed in the different groups) before starting the treatment period.
Exposure period (pre-mating and mating periods)
No indication of test item related effect was seen in the oestrus cycle data during the pre-mating and mating periods (mean cycle length was 4.00, 4.03, 4.08, 4.13 and 4.23 days in the Control, Low, Mid, High and Ultra-High dose groups, respectively).
Prolonged oestrus was recorded for one (1/12) High and three (3/12) Ultra-High dose females. The incidence in the Ultra High dose was considered as being a test item related effect.
Prolonged dioestrus was noted for one Low dose female (#2505), one Mid dose female and four Ultra High dose females. Statistically significantly increase of the number of Ultra High dose females in prolonged dioestrus was considered as being a test item related effect as it is outside the historical range.
Pseudo-pregnancy was noted for 1, 2, 3 and 2 in Low, Mid, High and Ultra-High dose females but this frequency was in line with the normal, expected range. - Reproductive function: sperm measures:
- not examined
- Reproductive performance:
- effects observed, treatment-related
- Description (incidence and severity):
- There were test item related adverse effects for the Ultra High dose group with regard to reproductive ability, mating or gestation indices.
The mating index was 100% in all groups (males and females). The fertility index was 100%, 83%, 91%, 92% and 67% in the Control, Low, Mid, High and Ultra High dose groups for males and 100%, 83%, 91%, 92% and 25% in the Control, Low, Mid, High and Ultra High dose females. The gestation index was 100% in all groups (all pregnant animals produced litters).
Eight females in the Ultra High dose group were non pregnant. It was considered as test item related effect.
Test item administration was considered to have no impact on the duration of the mating period. Successful coitus (sperm positive vaginal smears and/or vaginal plugs) occurred within 6 days of pairing (cohabitation). The mean duration of mating was 2.58, 2.83, 3.00, 3.08 and 4.17 days in the Control, Low, Mid, High and Ultra High dose groups, respectively. - Key result
- Dose descriptor:
- NOAEL
- Remarks:
- Reproductive effects
- Effect level:
- 50 mg/kg bw/day
- Based on:
- test mat.
- Sex:
- male/female
- Basis for effect level:
- reproductive performance
- Remarks on result:
- other: Based on effects on fertility, implantation and pups born
- Dose descriptor:
- NOAEL
- Remarks:
- Systemic toxicity
- Effect level:
- 200 mg/kg bw/day
- Based on:
- test mat.
- Sex:
- male/female
- Basis for effect level:
- body weight and weight gain
- food consumption and compound intake
- other:
- Remarks on result:
- other: based on relatively minor effects in clinical symptoms, body weight gain and food consumption
- Clinical signs:
- effects observed, treatment-related
- Description (incidence and severity):
- There was a test item related effect on mortality or survival of the pups (F1 generation).
The mean number of viable pups were statistically significantly decreased in the High and Ultra High dose groups (p<0.01 and p<0.05), data were outside of the historical control range for the High and Ultra High dose groups, and it is considered as test item related effect.
Pre-natal mortality, mean for the High dose group was statistically significantly changed (p<0.05) compared to the Control.
There were no other significant differences or effects that could be ascribed to treatment on the post-natal mortality values in any of the dose groups.
Evidence of suckling was recorded for all live born pups in the study. - Dermal irritation (if dermal study):
- not examined
- Mortality / viability:
- mortality observed, treatment-related
- Description (incidence and severity):
- There was a test item related effect on mortality or survival of the pups (F1 generation).
The mean number of viable pups were statistically significantly decreased in the High and Ultra High dose groups (p<0.01 and p<0.05), data were outside of the historical control range for the High and Ultra High dose groups, and it is considered as test item related effect.
Pre-natal mortality, mean for the High dose group was statistically significantly changed (p<0.05) compared to the Control.
There were no other significant differences or effects that could be ascribed to treatment on the post-natal mortality values in any of the dose groups.
Evidence of suckling was recorded for all live born pups in the study. - Body weight and weight changes:
- no effects observed
- Description (incidence and severity):
- There were no differences in the offspring body weights or weight gains.
Statistically significantly increased litter mean male pup body weight was observed on PND 0 and PND4 in case of the High dose group but without dose response. The data were within the historical control range.
There were statistically significantly decreased mean pup body weight gain per litter (PND4-PND13) in the Ultra High dose group (p<0.05 and p<0.01). - 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
- Anogenital distance (AGD):
- no effects observed
- Description (incidence and severity):
- No test item related effect was observed on anogenital distance or nipple retention during the study.
No statistically significant changes in the anogenital distance measured on PND 0 were noted for test item treated male and female pups when litter mean values were compared to control - Nipple retention in male pups:
- no effects observed
- Description (incidence and severity):
- No nipples/areolae presence seen in any of the male pups on PND 13
- Organ weight findings including organ / body weight ratios:
- no effects observed
- Description (incidence and severity):
- No test item-related effects were observed in the organ weights of the test item treated female and male animals compared to controls.
Terminal body weights of animals were not statistically significantly different between the groups. There were no treatment-related statistically significant differences among groups of females in the weights of organs measured when compared to Controls.
Weights of sex organs (absolute, body and brain related) in the Ultra High dose male group were all lower than the Controls, but without statistical significance. - Gross pathological findings:
- no effects observed
- Description (incidence and severity):
- TERMINAL EUTHANASIA / F1 Generation (PND 13)
Macroscopic Findings
No test item-related macroscopic findings were observed. - Histopathological findings:
- not examined
- Behaviour (functional findings):
- not examined
- Developmental immunotoxicity:
- not examined
- Key result
- Dose descriptor:
- NOAEL
- Remarks:
- pup development and survival
- Generation:
- F1
- Effect level:
- 200 mg/kg bw/day
- Based on:
- test mat.
- Sex:
- male/female
- Basis for effect level:
- mortality
- other:
- Remarks on result:
- other: normal post-natal mortality and reduced pup growth
- Key result
- Reproductive effects observed:
- yes
- Lowest effective dose / conc.:
- 200 mg/kg bw/day
- Treatment related:
- yes
- Relation to other toxic effects:
- reproductive effects occurring together with other toxic effects, but not as a secondary non-specific consequence of other toxic effects
- Dose response relationship:
- yes
- Relevant for humans:
- not specified
- Conclusions:
- The NOAEL for systemic toxicity of the parental generation was considered to be
200 mg/kg bw/day
(based on relatively minor differences in clinical symptoms, body weight gain and food consumption).
The NOAEL for reproductive effects of the parental generation was considered to be 50 mg/kg bw/day
(based on effects on fertility, implantation and pups born).
The NOAEL for pup development and survival was considered to be 200 mg/kg bw/day
(based on effects on normal post-natal mortality but reduced pup growth). - Executive summary:
The purpose of this OECD No. 421 study was to obtain information on the possible toxic effects of BAB (Benzene, mono-C11-C13-branched alkyl derivatives) test item following repeated (daily) administration by oral gavage to Sprague Dawley (SD) rats at 4 dose levels. A control group received the vehicle only (Propylene glycol + 1% Polysorbate).
Male and female SD rats were treated for 2 weeks pre-mating and then during the mating/post-mating periods. This was 28 days in total for males. Females were treated throughout gestation and up to and including postpartum/lactation day (PPD) 13.
Parameters measured during the study included signs of morbidity and mortality twice daily, daily general and/or weekly detailed observation of clinical signs, weekly body weight and food consumption. The reproductive performance, pregnancy, parturition and postpartum/lactation period were monitored in the adult animals, and viability, clinical signs and development were evaluated in their F1 offspring until post-natal day (PND13). At termination, necropsy with macroscopic examination was performed. Weights of selected organs were recorded, and representative tissues/organs were sampled and preserved in appropriate fixatives from the adult animals and/or offspring.
The dose levels were selected by the Sponsor in consultation with the Study Director based on the results of an OECD 407 study (CIT/Study No. 36997 TSR, [8]) and 90 days toxicity test (FR – 11995.307.001.13[9]). Based on these data, 800 mg/kg bw/day was chosen as High dose level in this study. Lower doses were spaced with a factor of 4.
Experimental design
Group Number
Group designation
Dose level
(mg/kg bw/day)Dose formulation concentration
(mg/mL)
Dose formulation volume
(mL/kg bw)
Animal numbers
Male
Female
1
Control
-
-
5
1001-1012
1501-1512
2
Low Dose
12.5
2.5
2001-2012
2501-2512
3
Mid Dose
50
10
3001-3012
3501-3512
4
High Dose
200
40
4001-4012
4501-4512
5
Ultra-High Dose
800
160
5001-5012
5501-5512
In summary, under the conditions of this study the daily administration of BAB (Benzene, mono-C11-C13-branched alkyl derivatives) by oral gavage to SD rats at dose levels of 12.5, 50, 200 and 800 mg/kg bw/day (Low, Mid, High and Ultra High dose groups, respectively) did not result in test item related mortality for adult animals.
Test item related clinical symptoms (decreased activity, hunched back, noisy respiration and piloerection in 1 to 4/12 animals per group) were observed mainly in the High and Ultra High dose parental groups.
There was a body weight loss in High & Ultra High males in the first 7 days, with a low food intake but based on the body weight gain and food consumption data was close to controls thereafter.
The High and Ultra High dose females were unaffected up until mating, but had reduced growth during gestation, which was probably related to the lower litter sizes in these animals.
The increased incidence of Ultra High dose females in prolonged dioestrus and prolonged oestrus was considered as being a test item related effect (probably related to the low pregnancy rate).
There were test item related adverse effects for the Ultra High dose group with regard to fertility index, with only 3/12 females producing a litter.
The number of females in the Ultra High dose group with no corpora lutea was relatively high, mean numbers of implantation sites was statistically significantly decreased and well below the historic control data.
The High dose females were partially affected with lower implantation numbers. These were considered as test item related adverse effects; in the absence of any signs of maternal toxicity at the time of mating these appear to be a direct effect on the reproduction system.There were no adverse effects on the F1 offspring clinical signs, physical or sexual development. There were very low number of litters in the Ultra High dose group. The Low and Mid dose groups were unaffected. There were test item related adverse effects on the mean number of pups born and the number of viable pups in the Ultra High dose group; the High dose group was affected to a lesser extent.
No test item related macroscopic finding was recorded for F1 pups at necropsy.
No test item related macroscopic changes were recorded at necropsy of routine organs/tissues or in any reproductive organs.
Under the experimental conditions of this study and based on the results thyroid weights, nipple retention, anogenital distance and external reproductive organs analysis and reproductive performance, there was no evidence for any endocrine effects.
The NOAEL for systemic toxicity of the parental generation was considered to be
200 mg/kg bw/day
(based on relatively minor differences in clinical symptoms, body weight gain and food consumption).The NOAEL for reproductive effects of the parental generation was considered to be 50 mg/kg bw/day
(based on effects on fertility, implantation and pups born).The NOAEL for pup development and survival was considered to be 200 mg/kg bw/day
(based on normal post-natal mortality but reduced pup growth).- Endpoint:
- reproductive toxicity, other
- Remarks:
- other: OECD Guideline 408 compliant study with spermiological examination
- Type of information:
- experimental study
- Adequacy of study:
- key study
- Study period:
- 11 December 2013 - 05 July 2014
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Reason / purpose for cross-reference:
- reference to same study
- Qualifier:
- according to guideline
- Guideline:
- other: OECD guideline 408
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Limit test:
- no
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- TEST ANIMALS
- Source: BIOAGRI Laboratórios – DF/ Brazil
- Age at study initiation: 7-8 weeks
- Housing: Animals were housed individually in polypropylene rodent cages (41 x 34 x 19 cm) with wire lids on top
- Diet: Animals were provided a conventional laboratory diet for Rodents (Nuvilab CR -1, Nuvital Nutrientes Ltda, Curitiba – PR, Brazil), ad libitum
- Water: Drinking water supplied by CAESB (Companhia de Saneamento Ambiental do Distrito Federal), ad libitum
- Acclimation period: 5 days
ENVIRONMENTAL CONDITIONS
- Temperature: 20.3 – 23.1 ° C
- Humidity: 44.9-67.6 %
- Air changes: 10-20 air changes per hour
- Photoperiod: 12 h dark / 12 h light - Route of administration:
- oral: feed
- Vehicle:
- unchanged (no vehicle)
- Details on exposure:
- DIET PREPARATION
- For each dose level, the test item was weighted in a beaker, added to the ground plain ration and turned into flour. The test diets were prepared each 15 days and checked for concentration and homogeneity. - Details on mating procedure:
- Not applicable
- Analytical verification of doses or concentrations:
- yes
- Details on analytical verification of doses or concentrations:
- Stability analysis: Stability analysis of the test item in feed was performed in a separate study (Study No.: 11995.020.035.13). The test item in the diet was stable for 16 days. Then, the formulation was prepared each 15 days.
Concentrations and homogeneity: The concentration and homogeneity of the test item for each group was determined for each new preparation.
Analyses of the preparations showed that they all fulfilled the acceptance criteria (i.e. nominal ± 10 %). - Duration of treatment / exposure:
- 13 weeks
- Frequency of treatment:
- Daily
- Details on study schedule:
- None
- Remarks:
- Doses / Concentrations:
300, 1000 and 3000 ppm
Basis:
nominal in diet - No. of animals per sex per dose:
- Principal group: 10 animals/sex/dose for control, pair-fed, low (300 ppm), mid (1000 ppm) and high dose (3000 ppm)
Satellite group: 5 animals/sex/dose for control, pair-fed and high dose (3000 ppm) - Control animals:
- yes, plain diet
- other: pair-fed control group
- Details on study design:
- - Dose selection rationale: Based on the results of a preliminary 14-day oral toxicity study (Study No.: 11995.306.002.13), the following three dose levels were selected: 300, 1000 and 3000 ppm; the control groups received feed alone. In this preliminary study, major toxicological effects were a significant decrease in bodyweight and bodyweight gain at 3000 and 12000 ppm, associated with a decrease in food consumption, probably due to low palatability of the preparations.
- Rationale for animal assignment: At the end of acclimation period, healthy animals were randomly assigned to the experimental groups using a computerized randomization procedure and housed individually. Prior to randomization, the animals were weighed and a detailed clinical examination was performed. The required number of animals was selected according to their health status and body weight. At the beginning of the treatment, the body weight variation did not exceed ± 20 % of the mean weight of each sex.
- Rationale for selecting satellite groups: After 90 days of treatment, the test item administration was suppressed from the satellite animals and the animals necropsied after 28 days to verify possible reversibility of test item related effects.
- Post-exposure recovery period in satellite groups: 28 days - Positive control:
- None
- Parental animals: Observations and examinations:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: During acclimation period each rat was observed daily in the cage for signs of ill health, morbidity and/or mortality. During treatment period, all animals were observed for morbidity and/or mortality at least twice daily (in the morning and in the afternoon on working days), once daily on weekend and public holidays. All animals were also observed once daily for clinical signs.
DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: All animals were subjected to a careful physical examination outside the home cage, at approximately the same time, prior to the initiation of the treatment and once weekly during treatment period. Signs to be recorded included:
- changes in skin, fur, eyes, mucous membranes, occurrence of secretions and excretions, and autonomic activity (e.g., lacrimation, piloerection, pupil size, unusual respiratory pattern);
- changes in gait, posture and response to handling as well as the presence of clonic or tonic movements, stereotypes (e.g., excessive grooming, repetitive circling) or bizarre behaviour (e.g., self-mutilation, walking backwards).
BODY WEIGHT: Yes
- Time schedule for examinations: Animals were weighed prior to randomization, on the day of the first administration and twice a week during the treatment period, on the day before the scheduled necropsy (not-fasted) and on the day of the scheduled necropsy (fasted).
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption was evaluated daily for all animals during the treatment period.
- Mean test substance intake for each sex-group was calculated daily, individually, according to the food consumption and expressed as ppm.
WATER CONSUMPTION: No
OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: Ophthalmological examination was performed prior to the initiation of dosing and at the end of treatment period.
- Dose groups that were examined: Animals from all groups
HAEMATOLOGY AND CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: Before necropsy
- Anaesthetic used for blood collection: Yes (carbon dioxide)
- Animals fasted: Yes; overnight period of at least 12 h
- How many animals: Animals from all groups
- Blood samples were collected by intracardiac puncture for erythrogram (EDTA tubes), blood coagulation (sodium citrate tubes) and clinical biochemistry (tubes without anticoagulant).
- Parameters checked for haematology: Red blood cell count, hemoglobin concentration, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelet count, total white blood cell count, differential white blood cell counts (lymphocytes, monocytes, eosinophils, basophils, band neutrophils and segmented neutrophils), clotting parameters (prothrombin time and activated partial thromboplastin time)
- Parameters checked for clinical chemistry: Glucose, blood urea nitrogen, creatinine, total protein, globulin, albumin, albumin/globulin ratio, total bilirubin, calcium, total cholesterol, sodium, potassium, alkaline phosphatase, aspartate aminotransferase, alanine aminotransferase and triglycerides
URINALYSIS: Yes
- Time schedule for collection of urine: Before necropsy
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes; overnight period of at least 12 h
- Parameters checked: Volume, density, pH, smell, appearance (clarity), color, nitrites, protein, glucose, ketones, urobilinogen, bilirubin, occult blood, leukocytes, erythrocytes, epithelial cells, bacteria, mucus and crystal
NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: Functional Observational Battery (FOB) was performed on all animals during the 11th week of dosing.
- Dose groups that were examined: Animals from all groups
- Battery of functions tested:
Autonomic functions: lacrimation, salivation, palpebral closure, prominence of the eye, piloerection, respiration, urination and defecation;
Reactivity and sensitivity: sensor motor responses to approach tactile and tail flick;
Excitability: reactions to handling and behavior in an open field;
Gait and sensor motor coordination: degree of morbidity, gait pattern in an open field, aerial righting reflex and landing foot splay; and
Abnormal clinical signs: including convulsions, tremors, unusual behavior and deposits around the eyes, nose or mouth.- Sperm parameters (parental animals):
- Sperm motility, morphology, enumeration of homogenization-resistant spermatids and determination of the sperm reserve
- Litter observations:
- not applicable
- Postmortem examinations (parental animals):
- GROSS PATHOLOGY: Yes; A complete gross examination was performed on all animals after euthanasia by carbon dioxide inhalation. The following organs from each animal were weighed during necropsy:
Adrenals (right and left), brain, heart, kidneys (right and left), liver, pituitary gland, spleen, thymus, thyroids (with parathyroid), testis (right and left), epididymides (right and left), prostate, seminal vesicles, ovaries (right and left) and uterus
HISTOPATHOLOGY: Yes (see table) - Postmortem examinations (offspring):
- not applicable
- Statistics:
- Quantitative variables such as mean body weight and mean body weight change, food consumption, FOB, hematological assessment (erythrogram, leukogram, clotting time) and biochemistry were analyzed by One-Way Analysis of Variance (ANOVA), followed by Dunnett’s test if significance was detected. For qualitative or non-parametric data such as urinalysis, macroscopic and microscopic findings comparison was carried out using the Chi-Square Test. The level of significance was set at 5% and the statistical program used was SAS Software (SAS Institute Inc., Cary, NC).
- Reproductive indices:
- Not applicable
- Offspring viability indices:
- Not applicable
- Clinical signs:
- no effects observed
- Body weight and weight changes:
- effects observed, treatment-related
- Food consumption and compound intake (if feeding study):
- effects observed, treatment-related
- Organ weight findings including organ / body weight ratios:
- effects observed, treatment-related
- Histopathological findings: non-neoplastic:
- effects observed, treatment-related
- Other effects:
- effects observed, treatment-related
- Reproductive function: oestrous cycle:
- no effects observed
- Reproductive function: sperm measures:
- effects observed, treatment-related
- Reproductive performance:
- not examined
- Key result
- Dose descriptor:
- LOAEL
- Effect level:
- 300 ppm (nominal)
- Based on:
- test mat.
- Sex:
- male
- Basis for effect level:
- reproductive function (sperm measures)
- Clinical signs:
- not examined
- Mortality / viability:
- not examined
- Body weight and weight changes:
- not examined
- Sexual maturation:
- not examined
- Organ weight findings including organ / body weight ratios:
- not examined
- Gross pathological findings:
- not examined
- Histopathological findings:
- not examined
- Remarks on result:
- not measured/tested
- Reproductive effects observed:
- not specified
- Conclusions:
- Under these test conditions, no NOAEL (No Observed Adverse Effect Level) could be identified in this study because of the test item related and statistically significant lower sperm motility in the low dose group. The identified LOAEL was therefore 300 ppm.
- Executive summary:
In a repeated dose oral toxicity study conducted according to the OECD Guideline 408 and in compliance with GLP, test item, Tetrapropylene benzene was administered daily by feed to groups of Sprague-Dawley rats (10 animals/sex/dose) at dose-levels of 300, 1000 and 3000 ppm in the diet for 13 weeks. A control and pair-fed control groups were included in the study. Three satellite groups (5 animals/sex/group), corresponding to recovery groups, were used: control, pair-fed and 3000 ppm groups. After 90 days of treatment, the test item administration was suppressed and all satellite animals were necropsied at the end of a 28-day treatment-free period. Examinations during the study included: mortality, clinical signs, body weight, food consumption, neurobehavioural examination, ophthalmology, haematology, blood chemistry, urinalysis, spermiology, organ weights, gross pathology and histopathology.
No clinical signs or mortality occurred during the study. Compound-related effect was observed in food consumption in treated animals at 3000 ppm, more pronounced in males than in females. Lower food consumption was associated to the low palatability of the diet containing the test item at 3000 ppm and responsible for the decreased body weight and body weight gain in these groups. No significant changes in food consumption and body weight were noticed at 300 and 1000 ppm. Only statistically significant lower RBC values were seen at doses of 1000 ppm and 3000 ppm in males, which were considered reversible. Lower WBC was observed in treated and pair-fed animals compared to the controls; however, as this effect was found in pair-fed group, it could not be related to test item toxicity. In females, no statistically significant or dose-related findings were observed for all parameters. Only aspartate aminotransferase and triglycerides decreased dose proportionally with statistical significance at 3000 ppm only in males. No clear significant toxicological effect attributable to the test item could be identified from these analyses. No effect of the test item could be identified from the ophthalmology, urinalysis and neurobehavioural examinations. Compound related and reversible effects were observed in the high dose males in spleen, thymus, epididymides, seminal vesicles and prostate absolute weights, with statistically significant decreases recorded. In females, the only statistically significant differences in mean absolute organ weights were found for liver (increased weight) and ovaries (lower weight than control) in the high dose group. Minimal, partially reversible, microscopic changes were observed in testis and epididymides (treated males), liver (females) and kidneys, thymus and spleen (males and females). Changes in testis and epididymis completely disappeared during recovery period. Only partial recovery occurred in satellite males for thymus and spleen. In females, the microscopic changes observed could be considered as reversible and potentially not test item-related as these changes were also observed in control or pair-fed satellite groups. Spermiology showed statistically significant and dose related lower motility than control group. The difference between pair-fed and control group was small (5.2 %), but statistically significant which showed that feed restriction contributed to the effect. However, as it was more pronounced in the treated groups, a test item effect could not be excluded. Also, statistically significant higher frequencies of all types of spermatozoid abnormalities were observed in the high dose group. All these effects were at least partly reversible.
Under these test conditions, no NOAEL (No Observed Adverse Effect Level) could be identified in this study because of the test item related and statistically significant decrease in sperm motility in the low dose group. The LOAEL was 300 ppm.
- Endpoint:
- extended one-generation reproductive toxicity - with developmental immunotoxicity (Cohorts 1A, 1B without extension, and 3)
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- supporting study
- Study period:
- 2018
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- See attachment
- Reason / purpose for cross-reference:
- read-across source
- Endpoint:
- two-generation reproductive toxicity
- Remarks:
- based on test type (migrated information)
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Study period:
- not precised
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- other: The tested product is not the substance itself
- Qualifier:
- according to guideline
- Guideline:
- other: EPA/TSCA
- Principles of method if other than guideline:
- Parental rats and their offspring were observed weighed and examined for treatment-related effects
- GLP compliance:
- yes
- Limit test:
- yes
- Species:
- rat
- Strain:
- Sprague-Dawley
- Sex:
- male/female
- Details on test animals or test system and environmental conditions:
- CD rats (Charles River Breeding Laboratories) were housed in wire mesh cages and given free access to commercial laboratory feed (Ralston Purina Co. St Louis, MO) and tap water. Animal rooms were on a 12 h light/dark cycly ; the temperature range was 65-79°F and relative humidity was between 17 and 76 %
- Route of administration:
- other: ORAL
- Vehicle:
- corn oil
- Details on exposure:
- Rats designated as the Fo generation were given the test material at dosages of 0, 5, 50 and 500 mg/kg/day for a period of about 10 weeks before mating.
The offspring of the Fo generation designated as the F1 generation were dosed for an 11-week premating pariod. - Details on mating procedure:
- One male rat was cohoused with one female within the same treatment group nightly until evience of matig was observed or until 7 nights has elapsed.
At this time all unmated females were housed nightly with different males within their treatment group for a second 7 day interval. The same procedurewas repeatd for a third 7 day interval for unmated females. - Analytical verification of doses or concentrations:
- yes
- Details on analytical verification of doses or concentrations:
- Dosing solutions were analyzed for homogeneity of mixing an stability ; analyses for concentration were carried out periodically throughout the studies to confirm A-215 concentration.
- Duration of treatment / exposure:
- during premating, mating, gestation and lactation periods for females. Dosing of males continued for 2 weeks after mating.
- Frequency of treatment:
- no data
- Details on study schedule:
- Fo animals received a 10 week premating treatment period and were ten mated to produce a single litter. F1 adults were selected from the F1 litters.
F1 animals were dosed for 11 weeks before mating to produce a single litter.
Adults and weaned pups received a gross postmortem examination. - Remarks:
- Doses / Concentrations:
0,5,50 and 500 mg/kg
Basis:
nominal conc. - No. of animals per sex per dose:
- 4 groups of 30 males and 30 female rats
- Control animals:
- yes
- Details on study design:
- Aduts and weanling rats were observed for mortality and clinical signs of toxicity twice daily.
Detailed physical examination were performed weekly. - Parental animals: Observations and examinations:
- Reduced weight gain at 500 mg/kg dose
- Sperm parameters (parental animals):
- no data
- Litter observations:
- decrease in litter size
- Postmortem examinations (parental animals):
- Complete gross postmortem examination were done on all animals in the study, both adults and pups. The pituitary glands, testes and epididymides,
prostate and selinal vesicle, vagina, uterus, ovaries and gross lesions.
F1 males which had impregnated a female were euthanized 3 weeks after mating. F1 females that delivered a litter were euthanized after weaning of the F2 pups. - Postmortem examinations (offspring):
- Same tests as for the parental animals.
All F2 pups were euthanized at weaning. - Statistics:
- Mean body weights, mean weight change, food consumtion, corpora lutea, uterine implantation sites, numbers of live fetuses, number of resorptions,preimplantation loss ratio, resorption/implant ratio, gestation lengths, and number of offspring were analyzed statistically. Incidence data, which included mortality rates, pregnancy rates, fertility indices, mating indices, litter survival indices, the incidence of fetuses and litters with malformations and variations and the incidence of females with resorption sites were analyzed using contingency tables; The level of significance for analysis of variance was p < or equal to 0.01 ; for all other tests it was p < or equal to 0.05
- Offspring viability indices:
- reduced pup vialibility at the 500 mg/kg dose
- Clinical signs:
- not specified
- Body weight and weight changes:
- not specified
- Food consumption and compound intake (if feeding study):
- not specified
- Organ weight findings including organ / body weight ratios:
- not specified
- Histopathological findings: non-neoplastic:
- not specified
- Other effects:
- not specified
- Reproductive function: oestrous cycle:
- not specified
- Reproductive function: sperm measures:
- not specified
- Reproductive performance:
- not specified
- Dose descriptor:
- NOEL
- Effect level:
- ca. 50 mg/kg bw/day (nominal)
- Based on:
- not specified
- Sex:
- not specified
- Basis for effect level:
- body weight and weight gain
- Clinical signs:
- not specified
- Mortality / viability:
- mortality observed, treatment-related
- Description (incidence and severity):
- reduced at the high dose
- Body weight and weight changes:
- effects observed, treatment-related
- Description (incidence and severity):
- decrease in weight gain at the high dose
- Sexual maturation:
- not specified
- Organ weight findings including organ / body weight ratios:
- not specified
- Gross pathological findings:
- not specified
- Histopathological findings:
- not specified
- Dose descriptor:
- NOEL
- Generation:
- F1
- Effect level:
- ca. 5 mg/kg bw/day (nominal)
- Based on:
- not specified
- Sex:
- not specified
- Basis for effect level:
- body weight and weight gain
- Dose descriptor:
- NOEL
- Generation:
- F2
- Effect level:
- ca. 5 mg/kg bw/day (nominal)
- Based on:
- not specified
- Sex:
- not specified
- Basis for effect level:
- body weight and weight gain
- Reproductive effects observed:
- yes
- Lowest effective dose / conc.:
- 50 mg/kg bw/day (nominal)
- Treatment related:
- yes
- Relation to other toxic effects:
- not specified
- Conclusions:
- The noel for developmental toxicity was established at 125 mg/kg
- Executive summary:
A 2-generation study was performed on Sprague-Dawley rats with 0,5,50 and 500 mg/kg substance administered in cornoil.
Parental rats and their offspring were observed, weighed and examined for treatment-related efffects :
Maternal and parental general toxicity was found : reduced weight gain in the high does group
Reproductive toxicity observed in parental animals : reduced litter size in high-dose group
Reproductive toxicity observed in offspring : reduced survival and weight gain in high-does group
Referenceopen allclose all
The mean duration of pregnancy was comparable in the Control and test item treated groups (actual values are listed in Table Summary of the pregnancy evaluation).
As far as it could be observed during the study, the parturition was normal for all animals, no abnormal delivery was noted.
The number of implantation sites was statistically significantly decreased in the High (p<0.05) and in the Ultra High dose (p<0.01) groups compared to the control mean. The data were outside of the historical control range (mean ± SD = 16.1 ± 5.2) in case of the Ultra High dose group, hence it was considered as test item related clearly adverse effect; the similar but lesser effect in the High dose group appears to be treatment related.
There was statistically significant decrease on the number of pups born in the High (p<0.01) and in the Ultra High (p<0.05) dose groups, the value for the Ultra High dose group was at the lower limit of the normal range, hence it is considered as test item related adverse effect (for more details see Table Summary of the pregnancy evaluation).
PARENTAL
Selected body weight parameters of parental animals
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Number of animals | 12 | 12 | 12 | 12 | 12 |
|
Males, Body weight on Day 14 (g) | 476.9 | 476.4 | 475.5 | 448.8* | 448.1* | DN |
difference (%) | -0.1 | -0.3 | -5.9 | -6.0 |
| |
Males, Body weight on Day 27 (g) | 513.8 | 518.0 | 511.4 | 486.1 | 483.5 | NS |
difference (%) | 0.8 | -0.5 | -5.4 | -5.9 |
| |
Males, Body weight gain Day 0-7 (g) | 10.3 | 8.6 | 6.3 | -6.4* | -9.4** | DN |
difference (%) | -16.9 | -38.7 | -162.1 | -191.1 |
| |
Males, Body weight gain Day 7-27 (g) | 57.8 | 64.3 | 60.1 | 48.9 | 48.1 | NS |
difference (%) | 11.1 | 3.9 | -15.4 | -16.9 |
| |
Males, Body weight gain Day 0-27 (g) | 68.2 | 72.8 | 66.4 | 42.5* | 38.7* | DN |
difference (%) | 6.8 | -2.6 | -37.7 | -43.3 |
| |
Number of animals | 12 | 10 | 10 | 11 | 3 |
|
Females, Body weight on GD 20 (g) | 458.3 | 446.6 | 454.7 | 415.9 | 405.3 | NS |
difference (%) | -2.5 | -0.8 | -9.2 | -11.5 |
| |
Females, Body weight gain GD 0-20 (g) | 179.7 | 161.6 | 169.7 | 132.5** | 135.3 | DU |
difference (%) | -10.1 | -5.5 | -26.2 | -24.7 |
| |
Females, Body weight on PPD 13 (g) | 387.8 | 380.0 | 383.3 | 382.7 | 371.0 | NS |
difference (%) | -2.0 | -1.2 | -1.3 | -4.3 |
| |
Females, Body weight gain PPD 0-13 (g) | 36.4 | 37.2 | 41.8 | 50.5 | 42.7 | NS |
difference (%) | 2.2 | 14.8 | 38.7 | 17.2 |
| |
Females, Body weight gain Day 0-PPD13 (g) | 127.4 | 122.7 | 123.7 | 121.0 | 130.3 | NS |
difference (%) | -3.7 | -2.9 | -5.0 | 2.0 |
|
GD: Gestation Day, PPD: Post-partum Day
DN: Dunnett’s Multiple Range Test; DU: Dunn test,
NS: Statistically not significant when compared to the control.
Statistical significance compared to control: * = p<0.05, ** = p<0.01.
Selected daily food consumption parameters of parental animals (g/animal/day)
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Males, Food consumption Day 0-7 (g) | 21.54 | 20.81 | 20.48 | 17.01* | 15.40** | DU |
difference (%) | -3.4 | -4.9 | -21.0 | -28.5 |
| |
Males, Food consumption Day 7-14 (g) | 23.57 | 23.68 | 23.65 | 20.52 | 19.46** | DN |
difference (%) | 0.5 | 0.4 | -12.9 | -17.4 |
| |
Males, Food consumption Day 14-27 (g) | 24.86 | 24.91 | 24.38 | 21.91** | 21.83** | DN |
difference (%) | 0.2 | -1.9 | -11.9 | -12.2 |
| |
Females, Food consumption Day 0-14 (g) | 15.75 | 15.64 | 16.60 | 15.82 | 12.55** | DN |
difference (%) | -0.7 | 5.4 | 0.5 | -20.3 |
| |
Females, Food consumption GD 0-20 (g) | 24.84 | 24.04 | 23.72 | 21.46** | 22.93 | DN |
difference (%) | -3.2 | -4.5 | -13.6 | -7.7 |
| |
Females, Food consumption PPD 0-13 (g) | 51.07 | 48.05 | 50.24 | 45.75 | 43.77 | NS |
difference (%) | -5.9 | -1.6 | -10.4 | -14.3 |
|
GD: Gestation Day, PPD: Post-partum Day
DN: Dunnett’s Multiple Range Test; DU: Dunn test,
NS: Statistically not significant when compared to the control.
Statistical significance compared to control: * = p<0.05, ** = p<0.01
Summary of reproductive parameters (males)
Parameters | Dose groups (mg/kg bw/day) | ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose | |
Number of treated animals | 12 | 12 | 11 | 12 | 12 |
Number of males used for mating | 12 | 12 | 11 | 12 | 12 |
Number of pre-terminal death | 0 | 0 | 1 | 0 | 0 |
Number of successful mating | 12 | 12 | 11 | 12 | 12 |
Number of infertile animals | 0 | 2 | 1 | 1 | 4* |
Male mating index (%) | 100 | 100 | 100 | 100 | 100 |
Male fertility index (%) | 100 | 83 | 91 | 92 | 33 |
* Note: Although the males did not produce any implantations after mating, which classes the males as infertile, we can not exclude the very low female fertility of this group being the cause
Summary of reproductive parameters (females)
Parameters | Dose groups (mg/kg bw/day) | ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose | |
Number of treated animals | 12 | 12 | 12 | 12 | 12 |
Number of females used for mating | 12 | 12 | 11 | 12 | 12 |
Number of sperm positive females | 12 | 12 | 11 | 12 | 12 |
Number of females with no implantation sites | 0 | 2 | 1 | 1 | 8 |
Number of females with no corpora lutea | 0 | 2 | 1 | 1 | 4 |
Number of pregnant females | 12 | 10 | 10 | 11 | 3 |
Number of found dead pregnant | 0 | 0 | 0 | 0 | 1 |
Number of pregnant females with live born(s) | 12 | 10 | 10 | 10 | 3 |
Number of pregnant females with no pups | 0 | 0 | 0 | 1 | 0 |
Female mating index (%) | 100 | 100 | 100 | 100 | 100 |
Female fertility index (%) | 100 | 83 | 91 | 92 | 25 |
Female gestation index (%) | 100 | 100 | 100 | 100 | 100 |
Notes: Two non-pregnant females were observed in the Low dose group, one in the Mid dose group, one in the High dose group and eight in the Ultra-High dose group had total intrauterine mortality, but because corpora lutea were present they were counted as fertile.
Summary of the pregnancy evaluation
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Number of evaluated females | 12 | 10 | 10 | 10 | 3 |
|
Number of pregnant females | 12 | 10 | 10 | 11 | 3 |
|
Duration of pregnancy (days) | 22.25 | 22.30 | 22.20 | 22.60 | 22.67 | NS |
Number of implantations, mean | 17.75 | 13.75 | 16.55 | 12.17* | 3.45** | U |
Number of pups born, mean | 16.50 | 14.80 | 16.90 | 12.10** | 10.00* | D |
Number of live born pups, mean | 16.50 | 14.70 | 16.80 | 10.91** | 10.00* | U |
Pre-natal mortality, mean | 1.25 | 1.80 | 1.40 | 2.36 | 2.67 | NS |
Pre-natal mortality (PND0-13) (%), mean | 6.92 | 11.47 | 7.68 | 25.20* | 19.42 | U |
Post-natal mortality (PND0-13), mean | 0.50 | 0.40 | 0.40 | 0.30 | 0.00 | NS |
Post-natal mortality (%), mean | 2.91 | 2.35 | 2.05 | 1.61 | 0.00 | NS |
Total mortality (PND0-13), mean | 1.75 | 2.20 | 1.80 | 2.60 | 2.67 | NS |
Total mortality (PND0-13) (%), mean | 9.60 | 13.56 | 9.59 | 19.25 | 19.42 | NS |
D: Duncan’s Multiple Range Test; U: Mann-Whitney U-test,
NS: Statistically not significant when compared to the control.
Statistical significance compared to control: * = p<0.05, ** = p<0.01.
OFFSPRING
Summary of the offspring mortality
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Number of evaluated litters | 12 | 10 | 10 | 10 | 3 |
|
Number of pups born | 198/12 | 148/10 | 169/10 | 121/10** | 30/3** | CH |
Number of cannibalized pups | 1/1 | 2/1 | 2/1 | 1/1 | 0/0 | NA |
Number of autolyzed pups | 5/3 | 3/3 | 3/2 | 3/3 | 0/0 | NA |
Number of stillborn pups | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | NA |
Number of live born pups | 198/12 | 147/10 | 168/10 | 120/10 | 30/3 | NA |
Number of found dead pups (born alive) | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | NA |
Number of living pups on PND0 | 198/12 | 147/10 | 168/10 | 120/10 | 30/3 | NA |
Number of cannibalized pups (PND0-13) | 1/1 | 2/1 | 2/1 | 1/1 | 0/0 | NA |
Number of found dead, intact pups (PND0-13) | 0/0 | 0/0 | 0/0 | 0/0 | 0/0 | NA |
Total number of pups died (born alive) | 6 | 4 | 4 | 3 | 0 | NS |
Culled for blood sampling on PND4 | 24/12 | 18/9 | 19/10 | 16/8 | 2/1 | NA |
Culled for litter standardization on PND4 | 48/12 | 31/8 | 45/10 | 13/4 | 1/1 | NA |
Number of viable pups on PND13 | 120/12 | 94/10 | 100/10 | 88/10* | 27/3** | CH |
PND: Post-natal day, NS: Statistically not significant when compared to the control, NA: Not applicable
Statistical significance compared to control: * = p<0.05, ** = p<0.01, CH: Chi Square
Summary of survival (offspring)
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Number of evaluated litters | 12 | 10 | 10 | 10 | 3 |
|
Number of pups born, mean | 16.50 | 14.80 | 16.90 | 12.10** | 10.00* | D |
Number of live born pups, mean | 16.50 | 14.70 | 16.80 | 10.91** | 10.00* | U |
Number of living pups on PND13, mean | 10.00 | 9.40 | 10.00 | 8.80 | 9.00 | NS |
Pre-natal mortality, mean | 1.25 | 1.80 | 1.40 | 2.36 | 2.67 | NS |
Pre-natal mortality (%), mean | 6.92 | 11.47 | 7.68 | 25.20* | 19.42 | U |
Post-natal mortality on PND0-4, mean | 0.50 | 0.40 | 0.40 | 0.20 | 0.00 | NS |
Post-natal mortality on PND0-4 (%), mean | 2.91 | 2.35 | 2.05 | 1.08 | 0.00 | NS |
Total mortality on PND4, mean | 1.75 | 2.20 | 1.80 | 2.50 | 2.67 | NS |
Total mortality on PND4 (%), mean | 9.60 | 13.56 | 9.59 | 18.75 | 19.42 | NS |
Post-natal mortality on PND0-13, mean | 0.50 | 0.40 | 0.40 | 0.30 | 0.00 | NS |
Post-natal mortality on PND0-13 (%), mean | 2.91 | 2.35 | 2.05 | 1.61 | 0.00 | NS |
Total mortality on PND13, mean | 1.75 | 2.20 | 1.80 | 2.60 | 2.67 | NS |
Total mortality on PND13 (%), mean | 9.60 | 13.56 | 9.59 | 19.25 | 19.42 | NS |
Survival index on PND0 | 100.00 | 99.41 | 99.50 | 99.23 | 100.00 | NS |
Sex ratio % (Female) on PND0 | 51.44 | 46.75 | 54.52 | 48.67 | 47.33 | NS |
Survival index on PND4 | 97.09 | 97.65 | 97.95 | 98.92 | 100.00 | NS |
Sex ratio % (Female) on PND4 | 52.01 | 46.83 | 54.48 | 48.51 | 47.33 | NS |
Survival index on PND13 | 100.00 | 100.00 | 100.00 | 99.00 | 100.00 | NS |
Sex ratio % (Female) on PND13 | 50.00 | 48.50 | 53.00 | 51.94 | 48.61 | NS |
D: Duncan’s Multiple Range Test; U: Mann-Whitney U-test Versus Control,
NS: Statistically not significant when compared to the control.
Statistical significance compared to control: * = p<0.05, ** = p<0.01.
Anogenital distance
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Male pups |
| |||||
Number of evaluated litters | 12 | 10 | 10 | 10 | 3 |
|
Anogenital distance, litter mean of males (mm) | 3.60 | 3.58 | 3.62 | 3.88 | 3.92 | NS |
Minimum / Maximum value, litter mean (mm) | 3.2/3.8 | 3.3/3.9 | 3.1/4.2 | 3.4/4.2 | 3.7/4.1 |
|
Female pups |
| |||||
Number of evaluated litters | 12 | 10 | 10 | 10 | 3 |
|
Anogenital distance, litter mean of females (mm) | 1.77 | 1.82 | 1.75 | 1.87 | 1.85 | NS |
Minimum / Maximum value, litter mean (mm) | 1.6/1.9 | 1.7/2.3 | 1.5/1.9 | 1.6/2.3 | 1.7/2.0 |
|
NS: Statistically not significant when compared to the control
Selected body weight data (offspring)
Parameters | Dose groups (mg/kg bw/day) |
| ||||
Control | Low dose | Mid dose | High dose | Ultra-High dose |
| |
Number of evaluated litters | 12 | 10 | 10 | 10 | 3 |
|
Mean litter body weight (PND0), g | 6.662 | 6.972 | 6.739 | 7.483 | 7.453 | NS |
Mean litter body weight (PND4), g | 9.927 | 10.346 | 9.736 | 11.553 | 11.780 | NS |
Mean litter body weight gain (PND0-4), g | 3.264 | 3.353 | 2.987 | 4.057 | 4.327 | NS |
Mean litter body weight (PND13), g | 29.409 | 30.744 | 29.125 | 29.789 | 27.160 | NS |
Mean litter body weight gain (PND4-13), g | 19.466 | 20.340 | 19.269 | 18.136 | 15.346** | DN |
Mean litter body weight gain (PND0-13), g | 22.725 | 23.698 | 22.330 | 22.246 | 19.674 | NS |
PND: Post-natal day, DN: Dunnett’s Multiple Range Test; DU: Dunn test, NS: Statistically not significant when compared to the control. Statistical significance compared to control: * = p<0.05, ** = p<0.01
- No clinical signs or mortality occurred during the study.
BODY WEIGHT AND WEIGHT GAIN
- No significant differences in mean body weight (BW) were observed at 300 and 1000 ppm. A statistically significant decrease was observed in mean BW and mean body weight gain (BWG) in males and females treated at 3000 ppm and in males pair-fed group when compared to the controls. In the principal groups, decreases in BW were observed in males and females treated groups and pair-fed groups, from the beginning of the treatment.
- Lower overall BWG were observed in all treated groups in a dose proportional manner: -14.4, -16.1 and -46.6 % (males) and -9, -19 and -31 % (females) of the control group at low, mid and high doses, respectively. The pair-fed group had BWG comparable to the high dose group, i.e. -50 % in males and -33 % in females of the control groups.
- In satellite males, high dose and pair-fed groups usually displayed decreases in BW and BWG throughout the treatment period, similarly to main groups. At day 91, the BW difference between both groups was -20.4 and -12.2 % when compared to the control, statistically significant only for the 3000 ppm group (and slightly lower than the corresponding principal groups). The BWG was -28 and -44 % of the control group in pair-fed and 3000 ppm groups, respectively. During the recovery period, BWG in pair-fed and 3000 ppm groups almost doubled compared to control group. The overall BW for high dose and pair-fed group at day 120 was -14.2 % (statistically significant) and -5.2 % (not statistically significant) of control group, respectively. These changes in BW and BWG in males at high dose were consistently related to their lower food consumption than control group and was confirmed with the better performance of satellites animals after day 91 when the test item was removed from the feed (recovery period).
- In satellite females groups, no statistically significant differences in BW were found among the groups although overall BW were lower in pair-fed and 3000 ppm groups than control group, with isolated statistical differences between pair-fed and control group. BWG were -29 and -21 % lower than control group during the treatment period in pair-fed and 3000 ppm groups, respectively. During recovery, BWG tripled in pair-fed group and doubled in 3000 ppm group compared to control group. Changes in BW and BWG were related to lower food consumption in animals from the principal group at high dose and in pair-fed group; more marked in males and associated to low palatability of the ration at 3000 ppm. The increase in BW and BWG in satellites animals at 3000 ppm during recovery period supported the reversibility of these alterations, although satellite males of the 3000 ppm had still statistically significant lower bodyweights than control group.
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
- Compound-related effect was observed in Food Consumption (FC) in treated animals at 3000 ppm, more pronounced in males than in females, affecting the Body Weight (BW) and Body Weight Gain (BWG). Consistent lower daily FC values were noted in high dose and pair-fed groups i.e., overall FC: -25.5 and -24.9 % in males (statistically significant) and -10.8 and -11.7 % in females (sporadically statistically significant) of control groups, respectively. No significant changes in FC were noticed at 300 and 1000 ppm.
- In satellite males, the daily FC was usually lower between control group, high dose and pair-fed group, during the treatment period and sporadically statistically significant. In satellite females, overall lower FC: -14 and -12 % were observed in pair-fed and 3000 ppm treated groups, respectively. The overall FC during the recovery period was similar between all groups. These changes were associated to the low palatability of the diet containing the test item at 3000 ppm and responsible for the BW and BWG alterations in these groups.
- The animals were exposed to 300, 1000 and 3000 ppm, corresponding to a test item intake of 24, 75 and 223 mg/kg bw/day respectively for males and 27, 91 and 264 mg/kg bw/day respectively for females. Treated satellite groups were exposed to 3000 ppm, corresponding to 249 and 271 mg/kg bw/day for males and females, respectively.
OPHTHALMOSCOPIC EXAMINATION
- No ophthalmological findings were observed.
HAEMATOLOGY
- Only statistically significant lower RBC values were seen at doses of 1000 ppm and 3000 ppm (-5 and -9.2 %, respectively) in males when compared to control. In satellite males, the decrease in RBC was not statistically significant, which were considered reversible. In females, only numerical variations were observed when compared to the control group. No statistically significant or dose-related findings were observed for all parameters.
- Lower WBC was observed in treated and pair-fed animals compared to the controls. In males it was dose related trend and statistically significant at high dose (-40.6 %). As lower, statistically significant value was found in pair-fed group (-39.6%), this finding could not be related to a test item effect. In satellite males, WBC in pair-fed animals was similar to control group, while it was still lower than control (-19 %) but not statistically significant at high dose. In female treated rats, the decrease in WBC was lower, not dose proportional and not statistically significant when compared to control. In satellite treated animals the decrease was -22.7 % of the control group but it was not statistically significant.
- No biologically significant test item-related changes were observed in clotting parameters. Small numerical variations, not dose proportional, were observed in treated and pair-fed male and female animals compared to the controls. Exceptionally higher statistically significant APTT was found only at low dose females group, therefore not test item associated.
CLINICAL CHEMISTRY
- Aspartate aminotransferase (AST) and triglycerides were decreased dose proportionally with statistical significance at 3000 ppm in males. Other changes in male’s clinical chemistry values were usually small, not dose proportional even if statistically significant. No differences were found in satellite males when compared to control, except for AST.
- Like males, only sporadic statistically significant, almost never dose-related findings were observed in females. Only total bilirubin was statistically significantly lower in all treated groups, but also in pair-fed group, showing that it was not due to the test item. Also, control value in the satellite group was comparable to principal treated groups values, confirming that these lower values were not due to the test item but to high values in the principal control group.
- No clear significant toxicological effect attributable to the test item could be identified from these analyses.
URINALYSIS
- No biological differences were observed between control and treated rats, as well as the control-fed groups. Isolated statistically significant differences occurred, all within normal reference values and in pair-fed group, showing no test item-related effect.
NEUROBEHAVIOUR
- No biologically significant test item-related changes were observed during neurotoxicological testing in male or female treated rats and pair-fed animals when compared to the control groups. In males only numerical variations were seen in open field evaluation and functional observation battery. Isolated and not test item-related statistical differences were noted in females at mid dose (principal group) and in male and female satellite control groups.
ORGAN WEIGHTS
- In males, potential compound related effects were observed at 3000 ppm in spleen, thymus, epididymides, seminal vesicles and prostate absolute weights, with statistically significant decreases recorded. No relevant differences were found in males from low and mid doses when compared to the control group. Statistically significant differences were also found in heart and kidneys absolute weights but as they were observed in pair-fed and high dose groups, they could not be related to test item. No statistically significant changes were observed in absolute organs weights of the satellite males. Statistically significant increases in organ weights relative to bodyweight were observed in the high dose group, probably due to the mean lower BW observed in this group (-25 % of control group). Also, the spleen, thymus, epididymides, seminal vesicles and prostate weights relative to BW were not statistically different from control group, probably because of the same reason, although seminal vesicle and prostate weights showed still lower mean values than control group. Spleen, thymus, epididymides, seminal vesicles and prostate weights were also statistically significantly lower than control group when related to brain weight. As no differences in these organ weights were observed in the recovery animals, these test item-related changes were considered as reversible.
- In females, the only statistically significant differences in mean absolute organ weights were found for liver (increased weight) and ovaries (lower weight than control) in the high dose group. The same significant changes were observed in organ weights relative to brain weight with also a statistically significant lower spleen weight. Like males, many organ weights relative to BW were statistically significantly lower than control group at 3000 ppm, probably due to the lower mean BW observed in this group (-14 % of control group). These potential test item-related changes were reversible as no statistically significant changes in absolute and relative to brain weight organ weights were observed in the 3000 ppm group compared to control group in the satellite animals.
GROSS PATHOLOGY
- No test item-related gross findings were observed at necropsy.
HISTOPATHOLOGY: NON-NEOPLASTIC
- Minimal, partially reversible, microscopic changes were observed in testis and epididymides (treated males), liver (females) and kidneys, thymus and spleen (males and females). Changes in testis and epididymis completely disappeared during recovery period. Only partial recovery occurred in satellite males for thymus and spleen. In females, the microscopic changes observed could be considered as reversible and potentially not test item-related as these changes were also observed in control or pair-fed satellite groups.
OTHER
- Spermiology showed statistically significant and dose related lower motility than control group, was found in treated male rats. The difference between pair-fed and control group was small (5.2 %), but statistically significant which showed that feed restriction contributed to the effect. However, as it was more pronounced in the treated groups, a test item effect could not be excluded. Also, statistically significant higher frequencies of all types of spermatozoid abnormalities were observed in the high dose group. All these effects were at least partly reversible.
None
Effect on fertility: via oral route
- Endpoint conclusion:
- adverse effect observed
- Dose descriptor:
- LOAEL
- 24 mg/kg bw/day
- Study duration:
- subchronic
- Species:
- rat
- Quality of whole database:
- The study used to define the LOAEL is a GLP-compliant study conducted according to the OECD guideline 408.
Effect on fertility: via inhalation route
- Endpoint conclusion:
- no study available
Effect on fertility: via dermal route
- Endpoint conclusion:
- no study available
Effects on developmental toxicity
Description of key information
A two-generation reproduction study and a developmental study were conducted with the structural analogue linear alkylbenzene LAB, on rats using single daily doses provided by gastric intubation using corn oil as vehicle (Robinson , 1992). The observations of this study lead to the conclusion that linear alkylbenzenes should not be considered as a developmental toxicant since the effects that showed an increased incidence of ossification variations and delayed ossification only at dose levels including maternal toxicity cannot be considered as specific effects on prenatal development.
In a read-across hypothesis and justification report, which purpose was to draw up a proposal for a C&L consistent with the characteristics of the target substance, for use and handling and its safety, the information available of the studies conducted with BAB, LAB together with other information from structural analogues of expected similar metabolic behavior has been used to trace a toxicological profile as reliable as possible.
The remaining uncertainty can be addressed by adaptation of the assessment factors for DNEL derivation.
Considering the available information, no further testing is proposed. Furthermore, it is important to remind that the target substance is manufactured and processed in systems that reduce direct contact with workers, under strictly controlled conditions (see Section 3 of IUCLID file and exposure assessment in section 9 and 10 of the CSR). Due to the possible hazard, the classification as Repr. Cat. 2 H361 is assigned.
Link to relevant study records
- Endpoint:
- developmental toxicity
- Type of information:
- read-across from supporting substance (structural analogue or surrogate)
- Adequacy of study:
- supporting study
- Study period:
- 2018
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- study well documented, meets generally accepted scientific principles, acceptable for assessment
- Justification for type of information:
- See document with justification
Reference
Effect on developmental toxicity: via oral route
- Endpoint conclusion:
- adverse effect observed
- Dose descriptor:
- LOAEL
- 25 mg/kg bw/day
- Study duration:
- subchronic
- Species:
- rat
Effect on developmental toxicity: via inhalation route
- Endpoint conclusion:
- no study available
Effect on developmental toxicity: via dermal route
- Endpoint conclusion:
- no study available
Justification for classification or non-classification
Overall, considering the available repeated dose toxicity studies with spermiological examination on BAB, the findings in the two-generation reproduction study and the developmental study on the closest similar substances (LAB) and the controversial data on the structural analogues with low similarity index, the proposed classification in category Repr. 2 is expected be conservative enough.
Additional information
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.