Oligomerisation products of 2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane with acrylic acid and lauric acid

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 15, 2010 to June 02, 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

4,4'-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, esters with acrylic acid

EC Number:

500-130-2

EC Name:

4,4'-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, esters with acrylic acid

Cas Number:

55818-57-0

Molecular formula:

C27H32O8

IUPAC Name:

4,4'-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, esters with acrylic acid

Details on test material:

- Name of test material (as cited in study report): CAS 55818-57-0, 4,4’-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, esters with acrylic acid
- Physical state: White to yellowish viscous liquid
- Analytical purity: 100 %
- Purity test date: 16 March 2010
- Lot/batch No.: 56728
- Expiration date of the lot/batch: 31 October 2011
- Storage condition of test material: at ambient temperature (approximately 20°C), protected from light

Test animals

Species:

rat

Strain:

other: Crl:CD (SD)

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River, UK
- Age at study initiation: 9-10 weeks
- Weight at study initiation: 310 to 366 g for males and 207 to 244 g for females
- Housing: up to 5 during pre-mating for all animals and after mating for males, individually with litter for females during gestation and littering.
- Diet (e.g. ad libitum): standard rodent diet (SDS VRF1 Certified) ad libitum, except overnight before routine blood sampling for Toxicity subgroup animals.
- Water (e.g. ad libitum): potable water taken from the public supply, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 23
- Humidity (%): 40 to 70
- Photoperiod (hrs dark / hrs light): 12 h/12 h

IN-LIFE DATES: From: 20 January 2010 To: 13 March 2010

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

propylene glycol

Details on oral exposure:

PREPARATION OF DOSING SOLUTIONS: approximately 50% of the final volume of propylene glycol was added to the test material. The formulation was warmed in a water bath at approximately 50°C and stirred with a spatula until all the test material had dissolved and more propylene glycol was added to make up the required volume. Then, the formulation was returned to the container and mixed using a magnetic stirrer until homogeneous. If necessary, the dose was warmed again to aid homogenisation.
Initially all formulations were prepared freshly on the day of use and used within two hours of completion of preparation. However, following
confirmation of the results from a homogeneity and stability study (Huntingdon Life Sciences Study No. RAJ0005) formulations were prepared freshly each week and stored refrigerated (approximately 4°C) until required for use.

VEHICLE
- Concentration in vehicle: 20, 60 and 180 mg/mL
- Amount of vehicle (if gavage): constant dosage-volume of 5 mL/kg bw/day

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Samples of each formulation prepared for administration in the first and last weeks of the dosing period were analysed for achieved concentration of the test substance. Four samples were taken (nominally 1 mL accurately weighed) from all groups. Two assays from each group were analysed. The analytical method involved dissolution and dilution using acetonitrile followed by reverse phase high performance liquid chromatographic analysis with ultra-violet detection (230 nm). The mean concentrations of CAS 55818-57-0 in test formulations analysed for the study were within applied limits +10%/-15% of nominal concentrations, confirming accurate formulation, with the exception of one result, Week 1, Day 1, Group 2, 20 mg/mL which was 20.5% below nominal. Additional samples taken from the reformulated Week 1, Day 5, Group 2 formulation were therefore analysed and the achieved concentration was 1.5% above nominal, confirming the accuracy of formulation.

Duration of treatment / exposure:

Five consecutive weeks for Toxicity subgroup males and females and Reproductive subgroup males. Reproductive subgroup females were treated daily for two weeks prior to pairing, throughout pairing and up until the day prior to termination on Day 7 of lactation. Offspring were not dosed.

Frequency of treatment:

Once a day, 7 days a week

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

100 other: mg/kg bw/day (actual ingested)

Doses / concentrations 2

Dose / conc.:

300 other: mg/kg bw/day (actual ingested)

Doses / concentrations 3

Dose / conc.:

900 other: mg/kg bw/day (actual ingested)

No. of animals per sex per dose:

Toxicity subgroup: 5 males and 5 females/dose
Reproductive subgroup: 5 males and 10 females/dose

Control animals:

yes, concurrent vehicle

Details on study design:

Dose selection rationale: in a preliminary study (Huntingdon Life Sciences Study Number: RAJ0001), dose levels of 80, 250, 750 and 1000 mg/kg bw/day were employed and there was a suggestion of reduced bodyweight gain among males that received 1000 mg/kg bw/day. There was no evidence of an effect of treatment on clinical condition, food consumption, oestrous cycles or organ weights at any dose level investigated, and no treatment-related macroscopic abnormalities were observed. For this study, treatment would continue for approximately 5 weeks and females would be pregnant, therefore in recognition of the potential for reduced bodyweight gain, the high dose level was set at 900 mg/kg bw/day, the low dose of 100 mg/kg bw/day was chosen as an anticipated No Observed Adverse Effect Level (NOAEL), and the intermediate dose of 300 mg/kg bw/day at a logarithmic interval between the low and high doses.

Positive control:

None

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS:
Animals were inspected visually at least twice daily for evidence of ill-health or reaction to treatment. Cages were inspected daily for evidence of ill-health amongst the occupant(s). During the acclimatisation period, observations of the animals and their cages were recorded at least once per day.

DETAILED CLINICAL OBSERVATIONS:
Detailed observations were recorded in relation to dose administration. For the Toxicity subgroup animals and for Reproductive subgroup males these were recorded daily during the first week of treatment, twice weekly during Weeks 2 to 4 (middle and end of each week) and on one occasion during Week 5. For Reproductive subgroup females these were recorded daily during the first week of treatment, twice weekly during Week 2 of treatment, on Days 0, 4, 7, 11, 14 and 20 after mating and Day 4 of lactation.

Before treatment commenced and during each week of treatment, detailed physical examination and arena observations were performed on each animal (physical condition and behaviour during handling with particular attention to possible signs of neurotoxicity). For the Reproductive subgroup females during the post-mating period, these observations were conducted on Days 0, 7, 14 and 20 after mating and on Days 1 and 7 of lactation.

BODY WEIGHT:
Toxicity subgroup males and females and Reproductive subgroup males were weighed weekly throughout the study. Reproductive subgroup females were weighed weekly until mating was detected, on Days 0, 7, 14 and 20 after mating and on Days 1, 4, 6 and 7 of lactation.

FOOD CONSUMPTION:
The weight of food supplied to each cage, that remaining and an estimate of any spilled was recorded weekly for all animals for the first two weeks of treatment. Food consumption continued to be recorded weekly for the remaining three weeks of treatment for Toxicity subgroup females. Food consumption was not recorded during Week 3 of treatment for Toxicity subgroup males or Reproductive subgroup males as the animals were in pairing with the Reproductive subgroup females during this period. Food consumption was recorded, however, during Weeks 4 and 5 of treatment for these males.
For each Reproductive subgroup female, the weight of food supplied, that remaining and an estimate of any spilled was recorded for the periods Days 0-6, 7-13 and 14-19 after mating and Days 1-3 and 4-6 of lactation.

WATER CONSUMPTION:
Fluid intake was assessed by daily visual observation.

OTHER:
- SENSORY REACTIVITY:
Sensory reactivity and grip strength assessments were performed (before dosing) on all Toxicity subgroup animals during Week 5 of treatment. The following measurements, reflexes and responses were recorded: approach response, touch response, auditory startle reflex, tail pinch response and grip strength.

- MOTOR ACTIVITY: During Week 5 of treatment (before dosing), the motor activity of each Toxicity subgroup animal was measured using a Rodent Activity Monitoring System (Version 2.0.3). Animals were tested individually in clear polycarbonate cages and motor activity was measured by counting infra-red beam breaks over ten 6-minute intervals (one hour total).

- HAEMATOLOGY:
During Week 5 of treatment (after sensory reactivity, grip strength and motor activity assessments), blood samples were obtained from all Toxicity subgroup animals after overnight withdrawal of food. Animals were held under light general anaesthesia induced by isoflurane and blood samples were withdrawn from the sublingual vein. The following were measured using a Bayer Advia 120 haematology analyser: Haematocrit (Hct), Haemoglobin concentration (Hb), Erythrocyte count (RBC), Reticulocyte count (Retic), Mean cell haemoglobin (MCH), Mean cell haemoglobin concentration (MCHC), Mean cell volume (MCV), Total leucocyte count (WBC), Differential leucocyte count (Neutrophils (N), Lymphocytes (L), Eosinophils (E), Basophils (B)
Monocytes (M), Large unstained cells (LUC)) and Platelet count (Plt). The most common morphological changes, anisocytosis, micro/macrocytosis and hypo/hyperchromasia were recorded. Prothrombin time (PT) (using an ACL 3000 Plus analyser and IL PT-Fibrinogen reagent) and Activated partial thromboplastin time (APTT) (using an ACL 3000 Plus Analyser and IL APTT reagent) were also measured.

- BLOOD CHEMISTRY:
At the same time and using the same animals as for peripheral haematology, the plasma was examined using a Roche P Modular Analyser for: Alkaline phosphatase (ALP), Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Gamma-glutamyl transpeptidase (gGT), Total bilirubin (Bili), Bile Acids (BIAC), Urea, Creatinine (Creat), Glucose (Gluc), Total cholesterol (Chol), Triglycerides (Trig), Sodium (Na), Potassium (K), Chloride (Cl), Calcium (Ca), Inorganic phosphorus (Phos), Total protein (Total Prot) and Albumin (Alb) (by chemical assay).

Sacrifice and pathology:

SACRIFICE:
Toxicity subgroup males and females and Reproductive subgroup males were killed in Week 6 after completion of the Week 5 investigations.
Reproductive subgroup females were killed on Day 7 of lactation.

GROSS NECROPSY:
All animals were subject to a detailed necropsy. For Reproductive subgroup females, the number of uterine implantation sites was also recorded.

HISTOPATHOLOGY / ORGAN WEIGHTS:
The tissues indicated in Table 1 were weighed.
In the Toxicity subgroup, the following organs were fixed for histopathology: Adrenal glands, Peyer’s patch, Brain, Pituitary, Caecum, Prostate, Colon, Rectum, Duodenum, Sciatic nerves, Epididymides (L&R), Seminal vesicles and coagulation gland, Heart, Spinal cord, Ileum, Spleen, Jejunum, Sternum with marrow, Kidneys, Stomach, Liver, Testes (L&R), Lungs, Thymus, Lymph nodes (left axillary and mesenteric), Thyroid with parathyroids, Trachea, Mammary area (caudal), Urinary bladder, Oesophagus, Uterus with cervix and oviducts, Ovaries (L&R) and Vagina.
In the Reproductive subgroup, the following organs were fixed for histopathology: Mammary area (caudal), Testes (L&R), Ovaries (L&R), Uterus with cervix and oviducts, Pituitary, Vagina and Prostate. Samples of any abnormal tissues were also retained and processed for examination.
All tissues preserved for examination were examined for all Toxicity subgroup and Reproductive subgroup animals of Control group and 900 mg/kg bw/day group. In addition, based on the results of the initial assessment, the lungs and kidneys were examined from all Toxicity subgroup males in the 100 and 300 mg/kg bw/day groups.

Other examinations:

ESTROUS CYCLICITY (Parental animals):
For 15 days before pairing (including the day of pairing), daily vaginal smears (dry) were taken from all Reproductive subgroup females, using cotton swabs moistened with saline. The smears were subsequently examined to establish the duration and regularity of the oestrous cycle. After pairing with the male, smearing was continued using pipette lavage, until evidence of mating was observed.

LITTER OBSERVATIONS:
All litters were examined at approximately 24 hours after birth and then daily thereafter for clinical signs (evidence of ill health or reaction to treatment), litter size (mortality and consequent changes in litter size from Days 1-7 of age), sex ratio of each litter (recorded on Days 1, 4 and 7 of age) and individual bodyweight (recorded on Days 1, 4 and 7 of age).

GROSS EXAMINATION OF PUPS:
All live pups were sacrificed on day 7 and were subject to a detailed necropsy. Missing offspring and those grossly autolysed or grossly cannibalised could not be examined. All other offspring dying before Day 7 of age were also examined.

Statistics:

The following sequence of statistical tests was used for grip strength, motor activity, bodyweight, food consumption, organ weight, litter size and survival indices and clinical pathology data: 1) a parametric analysis was performed if Bartlett's test for variance homogeneity (Bartlett 1937) was not significant at the 1% level. The F1 approximate test was applied. If the F1 approximate test for monotonicity of dose-response was not significant at the 1% level, Williams' test for a monotonic trend was applied. If the F1 approximate test was significant, suggesting that the dose response was not monotone, Dunnett's test (Dunnett 1955, 1964) was performed instead. 2) a non-parametric analysis was performed if Bartlett's test was still significant at the 1% level following both logarithmic and square-root transformations. The H1 approximate test, the non-parametric equivalent of the F1 test described above, was applied. If the H1 approximate test for monotonicity of dose-response was not significant at the 1% level, Shirley's test for a monotonic trend was applied. If the H1 approximate test was significant, suggesting that the dose-response was not monotone, Steel's test (Steel 1959) was performed instead.
For organ weight data, analysis of covariance was performed. Sex ratio were analysed by Wald chi-square test.
For gestation length an exact two-tailed Linear-by-linear test (Cytel 1995), with equally spaced scores, was applied to all groups.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

no effects observed

Food efficiency:

not examined

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

no effects observed

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

not examined

Behaviour (functional findings):

no effects observed

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

CLINICAL SIGNS AND MORTALITY (PARENTAL ANIMALS):
One Reproductive subgroup male receiving 100 mg/kg bw/day was found dead prior to dose administration on Day 34 of the study. Ante mortem signs for this animal were restricted to noisy respiration (rales) on the previous day and there were no macroscopic abnormalities detected. In the absence of any other mortalities in this or higher dose groups, it was considered incidental and unrelated to treatment.

BODY WEIGHT AND FOOD CONSUMPTION (PARENTAL ANIMALS):
At 900 mg/kg/day, mean bodyweight gain was satistically significantly lower than Control during the first week of treatment (67% of Control). During the second week of treatment, the weight gain of these males remained slightly (but not significantly) lower than Control. Thereafter, mean weight gain was essentially similar to Control and overall mean gain during the treatment period (Week 0 to Week 5) was 81% of Control. The
mean bodyweight gain of males receiving 300 or 100 mg/kg bw/day was considered unaffected by treatment.
Mean bodyweight gain of females in all dose groups was considered unaffected by treatment throughout the study. It was noted that during the first two weeks of treatment, mean weight gain in all treated groups was lower than Control, and between Weeks 2 and 5 the weight gain of Toxicity subgroup females was higher than Control, with all differences attaining statistical significance. There was, however, no dose response apparent, and therefore these differences were considered to be of no toxicological importance.

TEST SUBSTANCE INTAKE (PARENTAL ANIMALS):
The mean food intake of males and females in all dose groups was considered unaffected by treatment throughout the study.

REPRODUCTIVE FUNCTION (ESTROUS CYCLE) AND REPRODUCTIVE PERFORMANCE (PARENTAL ANIMALS):
Oestrous cycle length, pre-coital interval, mating performance and fertility of the Reproductive subgroup females was unaffected by treatment.
There was no effect of treatment at any dose level investigated on the gestation length of Reproductive subgroup females. There were no instances of dystocia and the gestation index was 100% in all groups.
All animals mated at the first oestrus opportunity after cohabitation.

ORGAN WEIGHTS (PARENTAL ANIMALS):
At scheduled termination, Toxicity subgroup females in all treated groups showed slightly low mean unadjusted adrenal weights compared with Control, with a dose-related trend apparent and differences attaining statistical significance. All values were, however, within the 5-95% confidence limit of general HCD for rats of this age and strain (0.053-0.093 g).
All other differences in unadjusted and adjusted organ weights for Toxicity and Reproductive subgroup animals were small, and no clear relationship to treatment.

GROSS PATHOLOGY (PARENTAL ANIMALS):
There were no macroscopic abnormalities detected at scheduled termination of the Toxicity or Reproductive subgroup animals that were considered to represent an adverse effect of treatment.

HISTOPATHOLOGY (PARENTAL ANIMALS):
No test article related changes were observed in any of the organs microscopically examined from Toxicity and Reproductive subgroup animals.
Seminiferous tubules of all males of both the Toxicity and Reproductive subgroups were evaluated with respect to their stage in the spermatogenic cycle and integrity of various cell types present within the different stages. No cell or stage specific abnormalities were noted.
During initial microscopical examination, lungs from three Toxicity subgroup males receiving 900 mg/kg bw/day had minimal aggregations of alveolar macrophages. In addition, the kidney from one male in this group had minimal multiple cortical scarring, minimal focal cortical tubular basophilia and cortical tubular dilatation. To assess the toxicological significance of this finding, a trackdown was carried out on lungs and kidney from Toxicity
and Reproductive subgroup males given 100 or 300 mg/kg bw/day. Subsequent microscopical examination showed no dose dependent trend in severity or incidence level for these findings and hence they were considered as incidental.
The incidence and distribution of all the other findings were consistent with the common background for animals of this age at these laboratories.

SIGNS AND ARENA OBSERVATIONS (PARENTAL ANIMALS):
No signs were observed among treated males and females at routine physical examination or during the arena observations that were considered to be related to treatment.

SENSORY REACTIVITY OBSERVATIONS AND GRIP STRENGTH (PARENTAL ANIMALS):
Sensory reactivity observations and grip strength values for Toxicity subgroup animals were similar to those for Controls, and considered unaffected by treatment.

MOTOR ACTIVITY (PARENTAL ANIMALS):
No dose response was apparent and no association with treatment was identified.

HAEMATOLOGY (PARENTAL ANIMALS):
Assessment of haematological parameters for Toxicity subgroup animals during Week 5 of treatment revealed slightly prolonged prothrombin time among males and females receiving 900 or 300 mg/kg bw/day, with a dose-related trend apparent and statistical significance attained. The time for males receiving 900 mg/kg bw/day was marginally outside the 5-95% confidence limits of general Historical Control Data (HCD) for rats of this age and strain (13.2-16.4 seconds) but males in the 300 mg/kg bw/day were within the range, as were the females in the 300 or 900 mg/kg bw/day groups (13.4-17.6 seconds).
At 900 or 300 mg/kg bw/day, group mean activated partial thromboplastin time was slightly shortened compared with the concurrent Controls. A dose dependent trend was apparent, however statistical significance was not attained, and at 900 mg/kg bw/day the group mean time for males was influenced by one atypical animal with a particularly short clotting time (8.1 seconds). With this animal excluded from the group mean, the mean time for this group would be 14.6 seconds, and all group mean times for these groups would be within the 5-95% confidence limits of general (HCD) for rats of this age and strain (14.1-24.4 seconds for males and 10.0-19.0 seconds for females).
Some other minor inter-group differences in haematological parameters attained statistical significance, but no clear evidence of an adverse effect of treatment. Among all groups of treated males, the mean cell haemoglobin concentration was higher than Control, with a dose-response apparent. In the absence of any other changes in erythrocytic parameters, or a similar effect among females, these differences were considered likely to be fortuitous and unrelated to treatment.

BLOOD CHEMISTRY (PARENTAL ANIMALS):
During Week 5, total bilirubin and total bile acid concentrations were statistically significantly high in males receiving 900 or 300 mg/kg bw/day and females receiving 900 mg/kg bw/day. Total bilirubin concentrations for animals in the 900 mg/kg/day group were outside the 5-95% confidence limits of general HCD for rats of this age and strain (1-3 μmol/L for males and females); no HCD are available for total bile acid concentrations.
In addition, cholesterol concentrations were statistically significantly high in males and females in all treated groups with a dose related trend apparent; concentrations for males receiving 900 or 300 mg/kg bw/day and females receiving 900 mg/kg bw/day were outside the 5-95% confidence limits of general HCD (1.07-2.07 mmol/L for males and 1.25-2.97 mmol/L for females).

LITTER SIZE, SEX RATIO AND SURVIVAL INDICES (OFFSPRING): There was no effect of parental treatment at any dose level investigated on the mean number of implantation sites or litter size. Post-natal survival was unaffected by treatment, and the percentage of males in the litters in all groups was consistent between Days 1 and 7 of age, indicating that there was no preferential mortality of either sex.

CLINICAL SIGNS (OFFSPRING): There were no clinical signs observed for F1 offspring that were considered to be related to parental treatment.

BODY WEIGHT (OFFSPRING): There was no evidence of an adverse effect of parental treatment at any dose level investigated on mean offspring bodyweights at birth, or on subsequent weight gain to Day 7 of age.

GROSS PATHOLOGY (OFFSPRING): There were no macroscopic abnormalities detected among the offspring that died during the early post-natal period, or at scheduled termination on Day 7 of age that were attributable to parental treatment.

Effect levels

Key result

Dose descriptor:

NOAEL

Effect level:

> 900 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: gross pathology, clinical sign, organ weight, food consumption, and body weight.

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

Table 2: Main statistically significant changes in haematology and blood chemistry parameters Dose (mg/kg bw/day) 0 100 300 900 Males MCHC (g/dL) 35.3 ± 0.44 (n=5) 35.8 ± 0.44 * (n=5) 36.4 ± 0.25 ** (n=3) 36.8 ± 0.29 ** (n=5) PT (sec) 14.7 ± 0.29 (n=5) 14.3 ± 0.48 (n=5) 15.8 ± 0.57 ** (n=5) 16.5 ± 0.38 ** (n=5) Bili (µmol/L) 2± 0.5 (n=5) 2± 0.5 (n=5) 3± 0.4 ** (n=5) 5± 0.8 ** (n=5) BIAC (umol/L) 30.4± 16.71 (n=5) 38.8± 21.33 (n=5) 68.6± 26.54 * (n=5) 151.7± 27.29 ** (n=5) Chol (mmol/L) 1.32± 0.270 (n=5) 1.99± 0.227 ** (n=5) 2.91± 0.407 ** (n=5) 3.55± 0.178 ** (n=5) Females PT (sec) 14.7 ± 0.59 (n=5) 15.0 ± 0.37 (n=5) 15.7 ± 0.34 ** (n=4) 15.6 ± 0.37 ** (n=5) Bili (µmol/L) 2± 0.4 (n=5) 2± 0.0 (n=5) 3± 0.9 (n=5) 4± 0.8 ** (n=5) BIAC (umol/L) 16.0± 3.55 (n=5) 23.2± 16.24 (n=5) 67.4± 96.49 (n=5) 165.5± 77.74 ** (n=5) Chol (mmol/L) 1.42± 0.308 (n=5) 2.47± 0.413 ** (n=5) 2.70± 0.524 ** (n=5) 3.91± 0.598 ** (n=5)

Applicant's summary and conclusion

Conclusions:

Based on the results of this study, it was concluded that the NOAEL for systemic toxicity in the CD rat was 900 mg/kg bw/day.

Executive summary:

The study on test substance was conducted in accordance with GLP and OECD guideline 422, three groups each comprising five male and five female rats for the toxicity subgroup and five male and ten female rats for the reproductive subgroup received 4,4’-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, esters with acrylic acid at doses of 100, 300 or 900 mg/kg bw/day. Toxicity subgroup males and females and reproductive subgroup males were treated daily for five consecutive weeks. Reproductive subgroup females were treated daily for two weeks before pairing, throughout pairing, gestation, and lactation until the day prior to termination on Day 7 of lactation. A similarly constituted control group received the vehicle, propylene glycol, at the same volume-dose.

During the study, data was recorded on clinical condition, performance under detailed physical and arena examination, sensory reactivity, grip strength, motor activity, bodyweight, food consumption, water consumption (visual), haematology, blood chemistry, oestrous cycles, mating performance, and fertility and gestation length. Organ weight, macroscopic, and microscopic pathology investigations were undertaken in the adults. The clinical condition of offspring, litter size and survival, sex ratio, and offspring bodyweight were assessed and macroscopic pathology investigations were undertaken.

There was only one mortality during the course of the study, therefore considered unrelated to treatment. There were no signs observed among treated males and females at the routine physical examination or during the arena observations that were considered to be related to treatment. There was no effect of treatment on the food consumption, sensory reactivity findings, grip strength values, and motor activity in males and females throughout the study.

At 900 mg/kg bw/day, the mean bodyweight gain of males was slightly lower than control during the first week of treatment. During the second week, weight gain for these males remained slightly (but not significantly) lower than control, but thereafter, mean weight gain was essentially similar to control in all treated groups, and the bodyweight gain of females during gestation and lactation was unaffected by treatment at all dose levels investigated.

Haematological assessment revealed slightly prolonged prothrombin time among males and females receiving 900 or 300 mg/kg bw/day. Biochemical changes in the blood plasma comprised high total bilirubin and total bile acid concentrations in males receiving 900 or 300 mg/kg bw/day and females receiving 900 mg/kg bw/day, and high cholesterol concentrations in males and females in all treated groups. A dose-related trend was evident for all of these haematological and biochemical parameters.

There was no clear evidence of an adverse effect of treatment on mean organ weights among all animals at scheduled termination. There were no macroscopic abnormalities and no test substance-related lesions at microscopic examination.

Oestrous cycle length, pre-coital interval, mating performance, and fertility and gestation length of the reproductive subgroup females were unaffected by treatment. There were no clinical signs observed for F1 offspring that were considered to be related to parental treatment and offspring survival and growth from birth to Day 7 of age were unaffected by treatment. There were no macroscopic abnormalities detected among the offspring that died during the early post-natal period, or at scheduled termination on Day 7 of age that were attributable to parental treatment. Based on the results of this study, it was concluded that the NOAEL for systemic toxicity in the CD rat was 900 mg/kg bw/day (Stannard, 2010).