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Toxicological information

Repeated dose toxicity: oral

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Administrative data

Endpoint:
short-term repeated dose toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP compliant guideline study, available as unpublished report, no restrictions, fully adequate for assessment

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report Date:
1991

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity in Rodents)
Qualifier:
according to
Guideline:
EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): FAT 40'400/A
- Lot/batch No.: BG 3247/TV 6
- Expiration date of the lot/batch: March 1995
- Stability: Stable
- Stability of test article dilution: at least 2 hours

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: BRL, Biological Research Laboratories Ltd., Wölferstrasse 4, CH-4414 Füllinsdorf
- Age at acclimation: 6 weeks
- Weight at acclimatization: males: 159 - 177 g, females: 161 - 175 g
- Housing: Individually in Makrolon type-3 cages with standard softwood bedding ("Lignocel", Schill AG, CH-4132 Muttenz)
- Diet: Pelleted standard Kliba 343, Batches 70/90, 71/90, 73/90 rat maintenance diet ("Kliba" Klingentalmuehle AG, CH-4303 Kaiseraugst), available ad libitum
- Water: Community water from Itingen, available ad libitum
- Acclimation period: Seven days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3
- Humidity (%): 40-70
- Air changes (per hr): 10-15
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
water
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 10mL/kg bw
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
Concentration, homogeneity and stability of the mixtures were determined during acclimatization. Further samples for analysis were taken during
acclimatization and during week 3 of the test, than kept deep frozen until later determination of analysis.
Duration of treatment / exposure:
up to 28 days
Frequency of treatment:
daily
Doses / concentrations
Remarks:
Doses / Concentrations:
50, 200, 1000 mg/kg bw
Basis:
actual ingested
No. of animals per sex per dose:
The number of rats assigned to toxicity and recovery testing per group were:
- 5 per sex for 50 and 200 mg/kg bw for the toxicity test
- 5 per sex for 0 and 1000 mg/kg bw for the recovering test
Control animals:
yes, concurrent vehicle
Details on study design:
FAT 40'400/A was administered to SPF-bred Wistar rats by repeated oral gavage, for a period of 28 days. The study was comprised of four groups, each containing five male and five female rats. The test article/vehicle mixture was administered on a mg/kg bw basis by oral gavage. The dose was based upon data received from acute studies and a 5-day oral (range-finding) gavage study. The animals of the control group were treated similarly with the vehicle alone. For the post-exposure recovery period two satellite groups exposed to 0 and 1000 mg/kg bw for 28 days consisting of five male and five female rats each were monitored for an additional 14 days after the end of the 28 days treatment period.

Examinations

Observations and examinations performed and frequency:
- Mortality/viability: Observations for mortality were recorded once daily.
- Clinical signs: Signs of toxicity were assessed once daily. Descriptions of all abnormalities were recorded and the subsequent progress was monitored.
- Food consumption: The food consumption was recorded once during the acclimatization period and weekly thereafter.
- Body weights: The body weight of each animal was recorded on the same days as the food consumption.
- Ophthalmoscopic examination: Ophthalmoscopic examinations were performed on all animals. A description of any abnormality was recorded. Examinations were performed at termination of treatment and a second time on the recovery individuals of groups 1 and 4 at termination of the recovery period. Ten minutes after the application of a mydriatic solution (Dispersa AG, CH-8400 Winterthur) the cornea, lens, anterior chamber, vitreous body and ocular fundus of both eyes were examined under dimmed light using a Heine Miroflex 2 Ophthalmoscope (Eisenhut Vet. AG, CH-4123 Allschwil).
- Haematology/clinical chemistry: Blood samples for hematology and clinical biochemistry were collected from all animals under light ether anesthesia at termination of treatment. The animals were fasted for approximately 18 hours before blood sampling but water was provided. Blood samples were collected from each animal between the hours of 7.00 and 9.30 a.m. to reduce biological variation caused by circadian rhythms. Blood samples were drawn from the retro-orbital plexus. Parameters being measured: erythrocyte count, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, platelet count, reticulocyte count, nucleated erythrocytes normoblasts, heinz bodies, methemoglobin, total leukocyte count, differential leukocyte count, red cell morphology, thromboplastin time, activated partial thromboplastin time, glucose, urea, creatinine, uric acid, bilirubin, cholesterol, triglycerides, phospholipids, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, creatine kinase, alkaline phosphatase, gamma-glutamyl-transferase, calcium, phosphorus, sodium, potassium, chloride, albumin, protein total.
- Urinalysis: Urine was collected during the 18-hour fasting period into a specimen vial using a metabolism cage, during which time the animals were deprived of food but allowed access to water ad libitum. Parameters being measured: volume (18 hour), specific gravity, pH, color, protein, glucose, ketone, bilirubin, blood, urobilinogen, urine sediment.
Sacrifice and pathology:
GROSS PATHOLOGY: Yes
- All animals were necropsied and descriptions of all macroscopic abnormalities were recorded. The following organ weights were taken from all animals necropsied at termination of treatment or recovery: adrenals, brain, heart, kidneys, liver, ovaries, pituitary gland, spleen, testes, thyroid gland.

HISTOPATHOLOGY: Yes
- Slides of adrenals, heart, kidneys, liver, spleen and stomach collected at terminal sacrifice from the animals of the control and high-dose groups were examined by a pathologist. The same applied to all gross lesions and to all animals which died spontaneously or had to be killed in extremis. Upon detection of treatment related morphologic changes in the organs of any high-dose animal, histologic evaluation of the same organs in all dose groups were performed. All abnormalities were described and included in the report.
Statistics:
The following statistical methods were used to analyze the body weights, food consumption, organ weights and clinical laboratory data: Univariate one-way analysis of variance was used to assess the significance of intergroup differences. If the variables could be assumed to follow a normal distribution, the Dunnett-test (many to one t-test) based on a pooled variance estimate was applied for the comparison between the treated groups and the control groups for each sex. The Steel-test (many-one rank test) was applied when the data could not be assumed to follow a normal distribution.

Results and discussion

Results of examinations

Details on results:
- Mortality: There were no unscheduled deaths during the study.
- Clinical signs: There were no clinical signs which could be attributed to the administration of the test substance. No clinical signs were recorded for any animal receiving the test substance.
- Food consumption: The administration of the test substance had no effect on food consumption or relative food consumption. No statistically significant differences among the group mean values being seen. The lower values seen in males receiving 50 mg/kg bw of the test substance are considered not to be due to treatment because of the lack of a dose-relationship.
- Body weights: The administration of the test substance had no effect on body weight gain, no statistically significant differences among the group mean values being seen. The lower values seen in males receiving 50 mg/kg bw of the test substance are considered not to be due to treatment because of the lack of a dose-relationship.
- Ophtalmoscopic examinations: The administration of the test substance had no effect on any ophthalmoscopy parameter, no abnormality being detected in any animal.
- Clinical laboratory investigations: The assessment of hematological, clinical biochemical and urinalysis data indicated no changes of toxicological significance at termination of the treatment nor at the end of the treatment-free recovery period. However, in the urinalysis 5 out of 10 male rats of group 4 (1000 mg/kg bw) indicated a deep yellow urin discoloration at termination of the treatment. This observation was attributed to the high concentration and yellowish nature of the test article and is not an indication of renal insufficiency. At termination of the treatment-free recovery period this finding was no longer observed. All other differences in the results of the clinical laboratory data were considered to be incidental and of normal biological variation for rats of the strain and age.
- Organ weights, organ to body weights and organ to brain weight ratios: In males, although there were no statistically significant differences in absolute organ weight between treated and control group means, there was evidence from organ/body and organ/brain weight ratios of a slight increase in liver and heart weights at 1000 mg/kg of the test substance after 4 weeks of treatment. After the 14 day treatment-free recovery period there was no evidence of a treatment-related effect. In females, heart weight in rats receiving the test substance was lower than in controls after 4 weeks of treatment but the fact that the differences were greater in the groups receiving 50 or 200 mg/kg bw than in the high dose group receiving 1000 mg/kg bw of the test substance suggests that this was not due to treatment. Similarly, although liver weight in high dose females after the 14 day treatment-free recovery period was higher than in control females, the absence of any treatment-related difference at the end of the dosing period suggest that this was not due to the administration of the test substance.
- Macroscopic findings: The administration of the test substance had no effect on the appearance of any organ or tissue at necropsy.
- Microscopic finding: The administration of the test substance had no effect on the microscopic appearance of any tissue.


Effect levels

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: Effect level based on clinical symptomps, body weight, food consumption, ophthalmoscopic examination, clinical laboratory investigations, and pathology

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
NOAEL was determined to be 1000mg/kg/bw.
Executive summary:

In a GLP compliant repeated toxicity study, performed according to OECD guideline 407, Wistar rats were treated with the test substance (50, 200, and 1000 mg/kg bw) by repeated oral gavage, for a period of 28 days. The study was comprised of four groups, each containing five male and five female rats. For the post-exposure recovery period two satellite groups exposed to 0 and 1000 mg/kg bw for 28 days consisting of five male and five female rats each were monitored for an additional 14 days after the end of the 28 days treatment period. No treatment related effects were observed on mortality, clinical signs, food consumption, body weight, ophthalmoscopic examinations, clinical laboratory investigations, macroscopic and microscopic findings. There was evidence that treatment of male rats with 1000 mg/kg of the test substance for 4 weeks was associated with a slight increase in liver weight which regressed during the treatment-free recovery period. There were no other differences in organ weight which could be attributed to treatment with the test substance. Therefore, the NOAEL was determined to be 1000 mg/kg/bw.