Esterification products of 4,4'-isopropylidenediphenol, ethoxylated and 2-methylprop-2-enoic acid

Endpoint summary

Description of key information

The repeated toxicity of Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid was evaluated in two reliable studies (2019, 2020).

No adverse effects were observed in rats after oral 28 -day and 90 -day of exposure up to the highest maximal dose of 1000 mg/kg/day (OECD TG 422 and 408).

Key value for chemical safety assessment

Toxic effect type:

dose-dependent

Repeated dose toxicity: via oral route - systemic effects

Link to relevant study records

Reference

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

June 2019 - May 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The test was initiated based on a request for information in a final ECHA decision (CCH-D-2114376213-53-01/F).

Qualifier:

according to guideline

Guideline:

OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity Study in Rodents)

Version / remarks:

25 June 2018

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.3100 (90-Day Oral Toxicity in Rodents)

Version / remarks:

August 1998

Deviations:

no

GLP compliance:

yes

Limit test:

no

Specific details on test material used for the study:

No correction factor applied.

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl CD® (SD) IGS BR, Caesarian Obtained, Barrier Sustained-Virus Antibody Free (COBS-VAF®)

Details on species / strain selection:

The rat was chosen because it is a rodent species accepted by Regulatory Authorities for this type of study. The Sprague-Dawley strain was selected since background data from previous studies are available at Charles River Laboratories Evreux.

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories Italia, Calco, Italy
- Females nulliparous and non-pregnant: yes
- Age at study initiation: approximately 6 weeks old
- Weight at study initiation: 180.8 - 233.9g (males) and 136.1 to 178.8g (females)
- Fasting period before study: No (except for at least 14 hours on completion of the treatment period)
- Housing: The animals were housed by two from the same sex and group, in polycarbonate cages with stainless steel lids containing autoclaved sawdust. Each cage contained rat hut and nylabone for environmental enrichment.
- Diet: rat/mouse pelleted maintenance diet (SSNIFF Spezialdiäten GmbH, Soest, Germany), ad libitum (except for at least 14 hours on completion of the treatment period)
- Water: free access to tap water (filtered with a 0.22 µm filter)
- Acclimation period: 13 days

DETAILS OF FOOD AND WATER QUALITY: The batches of diet and sawdust were analyzed by the Suppliers for composition and contaminant levels. Bacterial and chemical analyses of water are performed regularly by external laboratories. These analyses include the detection of possible contaminants (pesticides and heavy metals). No contaminants were present in the diet, drinking water or sawdust at levels which could have been expected to interfere with, or prejudice, the outcome of the study.

ENVIRONMENTAL CONDITIONS (SET CONDITIONS)
- Temperature (°C): 22 ± 2
- Humidity (%): 50 ± 20
- Air changes (per hr): approximately 8 to 15 cycles/hour of filtered, non-recycled air
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 16 Jul 2019 To: 7 Oct 2019

Route of administration:

oral: gavage

Details on route of administration:

The dose formulations were administered by gavage using a plastic syringe fitted with a plastic gavage tube, once a day, at approximately the same time. The outside of the gavage tube was carefully cleaned with an absorbent paper between each treatment.

Vehicle:

corn oil

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS:
Test dose formulations were prepared on the days of treatment. The preparation procedure was according to CRL No. 46148 AHS (homogeneity testing) describing the preparation procedure for a range of concentrations covering the lowest and highest used in this study. Formulations were kept at room temperature and protected from light and used within 4 hours after the end of their preparation. The control and test item dose formulations were stirred for at least 15 minutes before administration and were maintained under continuous magnetic stirring throughout the administration procedure.

VEHICLE
- Justification for use and choice of vehicle (if other than water): the test item could be dissolved in the vehicle.
- Concentration in vehicle: 0, 20, 60 and 200 mg/mL
- Amount of vehicle (if gavage): 5 mL/kg bw/day

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Determination of test item concentrations in dose formulations was performed once in Weeks 1, 4, 8 and 13. A sample was taken from control and test item dose formulations and analyzed using a validated method (HPLC/ UV). The analytical method was validated under CRL Evreux study number 46147 VAA prior to dose formulation analysis.

Acceptance criterion: Measured concentration = nominal concentration ± 10%

Duration of treatment / exposure:

13 weeks (i.e. 91 to 92 days)

Frequency of treatment:

Once daily

Dose / conc.:

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

Remarks:

Low dose group

Dose / conc.:

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

Remarks:

Mid dose group

Dose / conc.:

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

Remarks:

High dose group

No. of animals per sex per dose:

10

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale: The dose levels were selected based on the results of an OECD 422 study (CRL 46151 RSR). The test item treatment given by gavage at dose levels of 100, 300 or 1000 mg/kg bw/day was well tolerated and no adverse effects were noted at any dose levels for the F0 animals, therefore the same dose levels were selected for the current study.
- Fasting period before blood sampling for clinical biochemistry: yes (at least 14 hours).

Positive control:

Not included.

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule: At least twice a day

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: At least once a day before the beginning of the treatment period, and during the treatment period (between 1 and 3 hours post-dosing).

BODY WEIGHT: Yes
- Time schedule for examinations: The body weight of each animal was recorded once before the beginning of the treatment period, on the first day of treatment, and at least once a week until the end of the study.

FOOD CONSUMPTION:
- The quantity of food consumed by the animals in each cage was recorded at least once a week from the first day of treatment until the end of the study.

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: Yes
- Ophthalmological examinations were performed on all animals, before the beginning of the treatment period, and on control and high-dose animals on one occasion at the end of the treatment period.

HAEMATOLOGY: Yes
- Time schedule for collection of blood: At necropsy
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes (at least 14 hours o/n)
- How many animals: All
- Parameters as specified in the attached list were examined, including coagulation parameters.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood:
- Animals fasted: Yes (at least 14 hours o/n)
- How many animals: All
- Parameters as specified in the attached list were examined, including thyroid hormones (T3, T4 and TSH).

URINALYSIS: Yes
- Time schedule for collection of urine: overnight (at least 14 hours)
- Metabolism cages used for collection of urine: Yes (individual cages; urine was collected onto thymol crystals)
- Animals fasted: Yes
- Parameters as specified in the attached list were included.

NEUROBEHAVIOURAL EXAMINATION: No

IMMUNOLOGY: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
A complete macroscopic post-mortem examination was performed on all animals. This included examination of the external surfaces, all orifices, the cranial cavity, the external surfaces of the brain and spinal cord, the thoracic, abdominal and pelvic cavities with their associated organs and tissues and the neck with its associated organs and tissues. The body weight of each animal was recorded before euthanasia at the end of the treatment period. The organs as specified in the attached list were weighed wet as soon as possible after dissection. The ratio of organ weight to body weight (recorded immediately before euthanasia) was calculated.

HISTOPATHOLOGY: Yes
A microscopic examination was performed on all tissues (including thyroids with parathyroids and reproductive organs and tissues (see attached list) for control and high dose animals euthanized at the end of the treatment period, and on all macroscopic lesions, kidneys and liver from all low and mid dose animals euthanized on completion of the treatment period.

Statistics:

Provantis software was used to perform the statistical analysis of body weight, food consumption, hematology, coagulation, blood biochemistry, thyroid hormones and urinalysis data. PATHDATA software was used to perform the statistical analysis of organ weight data (level of significance of 0.05 or 0.01). Flowcharts of the analytical sequences are included as attachments.

Clinical signs:

no effects observed

Description (incidence and severity):

There were no test item-related clinical signs.
The clinical signs recorded during the study (i.e. alopecia, thin fur, scabs, wounds, soiled coat and hypersalivation) were considered as incidental as they were occasional and/or observed both in control and test item-treated animals and/or can commonly be encountered in laboratory animals.

Mortality:

no mortality observed

Description (incidence):

There was no intercurrent deaths during the course of the study.

Body weight and weight changes:

no effects observed

Description (incidence and severity):

There were no test item-related effects on body weight.
Body weight losses recorded in both sexes between Days 85 and 91 in all control and treated groups were considered to be likely related to blood collections during this period. Any other differences between control and test item treated groups were of minimal magnitude, observed with no dose-relationship and consistent with normal biological variations and were therefore not considered to be test item-related.

Food consumption and compound intake (if feeding study):

no effects observed

Description (incidence and severity):

There were no test item-related effects on food consumption.
Any differences between control and test item-treated groups, including those resulting in statistical differences, were transient and/or consistent with normal biological variation and/or observed sporadically with no dose-relationship and were therefore not considered to be test item-related.

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

no effects observed

Description (incidence and severity):

There were no ophthalmological findings at the end of the treatment period in animals up to 1000 mg/kg bw/day.

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

The main differences between control and test item-treated groups in the hematology parameters are presented in table 1 under additional information. At all dose levels in both sexes except in females at 100 mg/kg bw/day, and when compared with controls, statistically significant lower mean red blood cell count was noted at the end of the treatment period, along with lower mean hemoglobin concentration and hematocrit. At 100 mg/kg bw/day in females, a trend toward lower red blood cell count, hemoglobin concentration and hematocrit was also observed.
Starting from 100 mg/kg bw/day in females and when compared with controls, statistically significant, lower mean white blood cell count was noted, mainly due to lower mean lymphocyte counts on the same test item-treated groups.
Although these differences were of limited magnitude, comparable to historical control data values and poorly dose-related, they were considered to be test item-related.
All other variations in hematology parameters, including those that were statistically significant, were of low magnitude and/or observed with no dose relationship and/or consistent with normal biological variation and were therefore not considered to be test item-related.

There were no test item-related changes among coagulation parameters. The differences between control and test item-related groups, namely the shortened prothrombin time observed in males treated at 1000 mg/kg bw/day, was of low magnitude and within the limits of the historcial control data and therefore not considered to be test item-related.

Clinical biochemistry findings:

effects observed, treatment-related

Description (incidence and severity):

The main differences between control and test item-treated animals in the blood biochemistry parameters are presented in the table 2 under additional data.
Starting from 300 mg/kg bw/day in both sexes, higher mean total cholesterol levels, including higher HDL and LDL cholesterol, were noted at the end of the treatment period (at 1000 mg/kg bw/day, up to +55.1% in males and +87.1% in females, vs. controls).
These changes were above the upper limit of the historical control data but as no adverse histopathological findings correlated with these changes, they were considered to be non adverse. At 300 and 1000 mg/kg bw/day in females and when compared with controls, statistically significant, higher mean creatinine levels were seen at the end of the treatment period, associated with higher urea levels in females at 1000 mg/kg bw/day. These changes were considered to be non adverse as they were of low magnitude, within the limits of the historical control data, and not associated with adverse renal histopathological findings. All other variations in blood biochemistry parameters, including those that were statistically significant, were of low magnitude and/or observed with no dose relationship and/or consistent with normal biological variation and were therefore not considered to be test item-related.
There were no test item-related changes among thyroid hormones levels (T3, T4 and TSH). The differences between control and test item-related groups, including those reaching statistical significance, were within the range of the historical conrol data and/or of minimal magnitude and/or seen with no or poor dose-relationship and were therefore not considered to be test item-related.

Endocrine findings:

no effects observed

Urinalysis findings:

effects observed, non-treatment-related

Description (incidence and severity):

There were no test item-related findings among urinary parameters.
Starting from 100 mg/kg bw/day in both sexes, lower mean pH values were noted, reaching statistical significance except in females at 300 mg/kg bw/day. These differences were of low magnitude, within or close to the range of the historical control data and did not correlate with any other urinary changes. They were therefore not considered to be test item-related.

Behaviour (functional findings):

no effects observed

Immunological findings:

not examined

Organ weight findings including organ / body weight ratios:

effects observed, treatment-related

Description (incidence and severity):

Dose-related increased absolute and/or relative-to-body liver weights were noted in males and females treated at = 300 mg/kg bw/day (p<0.01). These differences correlated with hepatocellular hypertrophy at microscopic examination. Minimally increased absolute and relative-to-body kidney weights were noted in females at 1000 mg/kg bw/day (p<0.05 for the relative-to-body weights; statistical significance not reached for the absolute weights). These differences correlated with tubular vacuolation and dilatation at microscopic examination.
Minimally decreased absolute and relative-to-body thymus weights were noted in males at = 300 mg/kg bw/day (statistical significance not reached for the absolute and relative-to-body weights). These differences correlated with isolated lymphoid atrophy at microscopic examination.
The observed effects are summarized in Table 3 under additional information.
Other intergroup statistically and non-statistically significant differences were of low magnitude, discordant with no apparent relationship to dose, and were considered to be within the range of expected biological variations in the animals of this age kept under laboratory conditions. This included the minimally increased absolute and relative-to-body uterus weights in females treated at 1000 mg/kg/day. These differences were considered not to be related to test item administration in view of their low magnitude, since the statistical significance was not reached and since the isolated individual high weights at high dose-level correlated with dilated uterus at microscopic examination that was related to the expected estrous cycle (proestrus or estrus stage). The microscopic examination of female reproductive tract revealed no abnormalities.

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

There was test item-related enlargement in the liver from one female treated at 1000 mg/kg bw/day that correlated with slight hepatocellular hypertrophy. There was a small thymus, correlated with lymphoid atrophy, in one male treated at 300 mg/kg w/day and in one male treated at 1000 mg/kg bw/day. The few other gross changes were considered to be part of the spontaneous background seen in the rat kept under laboratory conditions. This included the black mass in the liver from one female treated at 1000 mg/kg bw/day that correlated with minimal angiestasis.

Neuropathological findings:

not examined

Histopathological findings: non-neoplastic:

effects observed, treatment-related

Description (incidence and severity):

Test item-related microscopic observations included:
- Increased incidence of minimal tubular dilatation and vacuolation in renal cortex was noted in males at 300 and/or 1000 mg/kg bw/day and in females treated at = 100 mg/kg bw/day, when compared to controls. These changes correlated with increased weights in females at 1000 mg/kg bw/day. In view of the low severity of these changes, they were considered to be non adverse at all dose levels.
- Minimal to slight, centrilobular to diffuse, hepatocellular hypertrophy in males and females at = 100 mg/kg bw/day. This correlated with increased liver weights. The effect was considered to be of low magnitude. As there were no associated deleterious changes as degeneration/necrosis, and since there were no clinical pathology correlates, this was considered to be non adverse.
- Isolated minimal or slight lymphoid atrophy was noted in the thymus from one male treated at 300 mg/kg bw/day and in one male treated at 1000 mg/kg bw/day. The relationship with the test item administration was considered to be equivocal in view of the poor dose-relationship.

The results are summarized in Table 4 under additional information. The other changes were considered not to be related to the test item administration since they were not dose-related, of low incidence and part of the spontaneous background in the rat kept under laboratory conditions.

In conclusion, at 1000 mg/kg bw/day, test item-related increased liver weights were noted in males and females. A minimal increase in kidney weights was noted in females. At microscopic examination, test item-related microscopic observations included non adverse renal changes (tubular dilatation and vacuolation), and non adverse hepatocellular hypertrophy in liver that correlated with gross enlargement in one female. At 300 mg/kg bw/day, test item-related increased liver weights were noted in males and females, correlated with non adverse hepatocellular hypertrophy. Test item-related microscopic observations included non adverse renal changes (tubular dilatation and vacuolation). At 100 mg/kg bw/day, there were no test item-related organ weight differences or gross changes. At microscopic examination, test item-related microscopic non adverse renal changes in females (tubular dilatation and/or vacuolation), and non adverse hepatocellular hypertrophy in the liver from males and females were seen.

Histopathological findings: neoplastic:

not examined

Key result

Dose descriptor:

NOAEL

Effect level:

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

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: No adverse effects observed up to and including the highest dose tested (1000 mg/kg bw/day).

Remarks on result:

not determinable due to absence of adverse toxic effects

Key result

Critical effects observed:

no

Conclusions:

A 13 week repeated dose study with oral administration of Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid in rats, performed according to OECD guideline 408 and in accordance with GLP principles, resulted in a NOAEL of 1000 mg/kg bw/day as no adverse effects were observed up to and including the highest dose level.

Executive summary:

The objective of this study was to evaluate the potential toxicity of the test item, Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid, following daily oral administration (gavage) to rats for 13 weeks.

Four groups of ten male and ten female Sprague-Dawley rats received the test item, Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid, at dose levels of 0, 100, 300 or 1000 mg/kg/day in the vehicle (corn oil) by the oral route (gavage) once a day for 13 consecutive weeks.

The animals were checked daily for mortality and clinical signs. Detailed clinical observations were performed once a week. Body weight was recorded pre-test, on the first day of treatment and then once a week. Food consumption was recorded weekly. Ophthalmological examinations were performed on all animals before the beginning of the study and on control- and high-dose animals in Week 13. Hematology, coagulation, blood biochemistry investigations and urinalysis were performed in all animals and TSH, T3 and T4 hormone levels were determined in Week 13. On completion of the treatment period, all animals were euthanized and a full macroscopic post-mortem examination was performed. Designated organs were weighed and selected tissues were preserved. A microscopic examination was performed on designated tissues from animals in the control and high-dose groups and on all macroscopic lesions, liver and kidneys from all low- and intermediate-dose animals.

 

No unscheduled deaths occurred during the study. The test item was well tolerated with no relevant clinical signs and no effects on body weight, food consumption, ophthalmological, coagulation parameters or thyroid hormones.

Slightly lower red blood cell count, hemoglobin levels and hematocrit were noted in males and females at all dose levels. Slightly lower white blood cell and lymphocyte counts were observed in females at all dose levels.These slight differences were statistically significant but poorly dose-related and comparable to historical control data, and therefore were considered as non adverse.

Moderately higher total cholesterol levels, including HDL and LDL cholesterol were noted in groups treated at 300 or 1000 mg/kg/day, higher creatinine levels at 300 mg/kg/day and higher urea and creatinine levels were noted in females at 1000 mg/kg/day. In the absence of associated adverse histopathological findings,these changes were considered to be non adverse.

Test item-related increased liver weights were noted in males and/or females at 300 and 1000 mg/kg/day, and increased kidney weights in females at 1000 mg/kg/day. At gross examination, there were test item-related enlargement in the liver from one female treated at 1000 mg/kg/day that correlated with slight hepatocellular hypertrophy, and small thymus that correlated with lymphoid atrophy, in one male treated at 300 mg/kg/day and in one male treated at 1000 mg/kg/day. Test item-related microscopic observations included non adverse increased severity and incidence of tubular vacuolation and dilatation in the kidney, and hepatocellular hypertrophy in males and females treated at all dose levels.

 

Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid administered daily for 13 consecutive weeks by gavage to male and females Sprague-Dawley rats at dose levels of 100, 300 or 1000 mg/kg/day was clinically well tolerated and did not induce adverse clinical pathology or histopathological changes. Under the experimental conditions of the study, the No Observed Adverse Effect Level (NOAEL) was set at 1000 mg/kg/day.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed

Dose descriptor:

NOAEL

1 000 mg/kg bw/day

Study duration:

subchronic

Species:

rat

Quality of whole database:

Both studies are considered to be reliable (study with a klimisch score of 1).

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion

Endpoint conclusion:

no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

90 -day repeated toxicity study (2020, OECD 408)

The objective of this study was to evaluate the potential toxicity of the test item, Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid, following daily oral administration (gavage) to rats for 13 weeks.

Four groups of ten male and ten female Sprague-Dawley rats received the test item, Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid, at dose levels of 0, 100, 300 or 1000 mg/kg/day in the vehicle (corn oil) by the oral route (gavage) once a day for 13 consecutive weeks.

The animals were checked daily for mortality and clinical signs. Detailed clinical observations were performed once a week. Body weight was recorded pre-test, on the first day of treatment and then once a week. Food consumption was recordedweekly. Ophthalmological examinations were performed on all animals before the beginning of the study and on control- and high-dose animals in Week 13. Hematology, coagulation, blood biochemistry investigations and urinalysis were performed in all animals and TSH, T3 and T4 hormone levels were determined in Week 13. On completion of the treatment period, all animals were euthanized and a full macroscopicpost-mortemexamination was performed. Designated organs were weighed and selected tissues were preserved. A microscopic examination was performed on designated tissues from animals in the control and high-dose groups and on all macroscopic lesions, liver and kidneys from all low- and intermediate-dose animals.

 

No unscheduled deaths occurred during the study. The test item was well tolerated with no relevant clinical signs and no effects on body weight, food consumption, ophthalmological, coagulation parameters or thyroid hormones.

Slightly lower red blood cell count, hemoglobin levels and hematocrit were noted in males and females at all dose levels. Slightly lower white blood cell and lymphocyte counts were observed in females at all dose levels.These slight differences were statistically significant but poorly dose-related and comparable to historical control data, and therefore were considered as non adverse.

Moderately higher total cholesterol levels, including HDL and LDL cholesterol were noted in groups treated at 300 or 1000 mg/kg/day, higher creatinine levels at 300 mg/kg/day and higher urea and creatinine levels were noted in females at 1000 mg/kg/day. In the absence of associated adverse histopathological findings,these changes were considered to be non adverse.

Test item-related increased liver weights were noted in males and/or females at 300 and 1000 mg/kg/day, and increased kidney weights in females at 1000 mg/kg/day. At gross examination, there were test item-related enlargement in the liver from one female treated at 1000 mg/kg/day that correlated with slight hepatocellular hypertrophy, and small thymus that correlated with lymphoid atrophy, in one male treated at 300 mg/kg/day and in one male treated at 1000 mg/kg/day. Test item-related microscopic observations included non adverse increased severity and incidence of tubular vacuolation and dilatation in the kidney, and hepatocellular hypertrophy in males and females treated at all dose levels.

 

Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid administered daily for 13 consecutive weeks by gavage to male and females Sprague-Dawley rats at dose levels of 100, 300 or 1000 mg/kg/day was clinically well tolerated and did not induce adverse clinical pathology or histopathological changes. Under the experimental conditions of the study, the No Observed Adverse Effect Level (NOAEL) was set at 1000 mg/kg/day.

 

28 -day repeated toxicity study (2019, OECD 422)

Three groups of ten male and ten female Sprague-Dawley rats received the test item daily by the oral route (gavage) at dose levels of 100, 300 or 1000 mg/kg/day, under a constant dosage volume of 5 mL/kg/day. Another group of ten male and ten female rats received the vehicle only (corn oil) under the same experimental conditions and acted as a control group.

Males were treated for an overall period of approximately 4 weeks: 2 weeks before mating, during the mating period (up to 2 weeks) until the day before euthanasia. Females were treated for an overall period of 7 to 9 weeks: 2 weeks before mating, through mating (up to 2 weeks) and gestation (3 weeks) until Day 13 post-partum (p.p.) inclusive.         

 

No test item-related deaths occurred during the study. Ptyalism was observed with dose-related increased incidences. This sign, commonly noted when a test item is administered by gavage, was not considered to represent an adverse effect. The functional observation battery and motor activity were unaffected by the test item treatment. Body weight and food consumption were not impaired by the test item treatment.

At laboratory investigations, higher cholesterol level was noted in males given 1000 mg/kg/day (1.9-foldvs.controls) with the same tendency at 100 and 300 mg/kg/day (+26 to +28%vs.controls). This isolated finding was considered to be non-adverse. Hematology and urinary parameters were not impacted by the test item treatment. Thyroid hormone analysis did not reveal any disturbances in F0 males at sacrifice.

At pathology, no gross test item-related changes were noted. Decreased adrenal weights were noted in males treated at 300 or 1000 mg/kg/day and correlated with microscopic non-adverse cortical atrophy at 1000 mg/kg/day. There was a trend towards increase in liver weights in males treated at 300 mg/kg/day and in females treated at 1000 mg/kg/day that correlated with non-adverse microscopic hepatocellular hypertrophy. Non-adverse microscopic hepatocellular hypertrophy was also observed in males at 1000 mg/kg/day.  Indeed, at microscopic examination, non-adverse tubular vacuolation was noted in the kidneys from one male and one female treated at 1000 mg/kg/day, together with non-adverse tubular basophilia in males treated at 100 mg/kg/day.

Non-adverse sinusoidal erythrocytes (i.e.hemorrhage) were noted in the mesenteric lymph node from males treated at 300 mg/kg/day and from females treated at 100 mg/kg/day.

 

Based on the experimental conditions of this study, the No Observed Adverse Effect Level (NOAEL) for parental toxicity was considered to be 1000 mg/kg/day in males and females based on the absence of adverse findings at this dose level.

Justification for classification or non-classification

Based on the 28 -day and 90 -day studies, no organ toxicity was observed in rats. Therefore, no classification of Reaction products of 4,4'-isopropylidenediphenol, ethoxylated and methacrylic acid is required for repeated toxicity according to the Regulation EC 1272/2008.