Registration Dossier

Administrative data

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
06 December 2006 to 16 March 2007
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted under GLP conditions.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2007
Report Date:
2007

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity in Rodents)
Deviations:
yes
Remarks:
The jejunum was not available for histopathological examination (an. 24). Evaluation: Sufficient information was available for the evaluation of the results. The study integrity was not adversely affected by the deviations.
Qualifier:
according to
Guideline:
other: EC Council Directive 96/54/EC, Annex IV.D.
Qualifier:
according to
Guideline:
other: Japanese Chemical Substances control Law 1987. Japanese Ministry of Health, Labor and Welfare (No. 031121002) Ministry of Economy, Trade and Industry (No.2). Ministry of Environment (No. 031121002).
Qualifier:
according to
Guideline:
other: US Environmental Protection Agency. OPPTS 870.3050.
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): MTDID 7145
- Substance type: clear colorless liquid
- Physical state: liquid
- Analytical purity: ~94.5%
- Lot/batch no.: Batch 142072:43
- Expiration date of the lot/batch: 30 December 2007
- Stability under test conditions: Stable
- Storage condition of test material: At room temperature in the dark
- Other: pH 7.2; stable at maximum temperature of 200 degrees C for up to 24 hours.
- Specific Gravity: 1.8

Test animals

Species:
rat
Strain:
other: White, outbred, SPH quality
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Deutschland, Sulzfeld, Germany
- Age at study initiation: Approximately 6 weeks
- Weight at study initiation: all animals +/- 20% sex mean weight
- Housing: 5 animals per sex in Macrolon cages (MIV type) with sterilised sawdust as a bedding material.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least five days
ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.6--22.6 degrees C
- Humidity (%): 36-74%
- Air changes (per hr): ~15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light with intermittant fluctuations (max 1 hour). Fluctuations do not affect study integrity.
IN-LIFE DATES: From: 2 February 2007 To: 2 March 2007 (main group) or 16 March 2007 (recovery groups)

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
oral: gavage : using a plastic feeding tube
Analytical verification of doses or concentrations:
yes
Details on analytical verification of doses or concentrations:
dose level (g/kg)/specific gravity (g/m). Actual dose volumes were calculated weekly according to latest body weight.
Duration of treatment / exposure:
at least 28 days
Frequency of treatment:
Gavaged once daily for at least 28 days, 7 days per week, at the approximate same time daily (max 4 hours difference between earliest and latest dose).
Doses / concentrations
Remarks:
Doses / Concentrations:

Basis:
other: Dose levels selected on the basis of a 5-day dose range finding study (NOTOX Project 459304). Dose levels administered at 250, 500 and 1000 mg/kg/day.
No. of animals per sex per dose:
5 animals per sex per dose
Control animals:
other: Yes, 1 main group controls/1 recovery group of controls
Details on study design:
- Dose selection rationale: by computer generated random algorithm according to body weight.
- Post-exposure recovery period in satellite groups: 14 days

Examinations

Observations and examinations performed and frequency:
DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: at least once daily. Once prior to start of treatment and on a weekly basis thereafter.
BODY WEIGHT: Yes
- Time schedule for examinations: Treatment period: days 1, 8, 15, 22, 28. Recovery period: days 1, 8, 14.
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study):
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: No
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 AND COMPOUND INTAKE (if drinking water study): No
- Time schedule for examinations:
OPHTHALMOSCOPIC EXAMINATION:No data
- Time schedule for examinations:
- Dose groups that were examined:
HAEMATOLOGY: Yes
- Time schedule for collection of blood: on the day of necropsy (7:00-10:30 a.m.)
- Anaesthetic used for blood collection: Yes (iso-flurane)
- Animals fasted: Yes, overnight (max 20 hours)
- How many animals: all (n=30).
- Parameters checked in table [1] were examined.
CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: on the day of necropsy (7:00-10:30 a.m.)
- Animals fasted: Yes, overnight (max 20 hours)
- How many animals: all (n=30)
- Parameters checked in table [2] were examined.
URINALYSIS: No data
- Time schedule for collection of urine:
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- Parameters checked in table [No.?] were examined.
NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: Week 4 of treatment
- Dose groups that were examined: all animals
- Battery of functions tested: Hearing ability, pupillary reflex, static righting reflex, grip strength, motor activity test
OTHER: MORTALITY/VIABILITY: at least twice daily

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):
not examined
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:
not specified
Histopathological findings: neoplastic:
not specified
Details on results:
CLINICAL SIGNS AND MORTALITY: Incidental findings that were noted included alopecia on back, forelegs or cervical region. These findings are commonly noted in rats of this age and strain and housed and treated unter the conditions in this study and considered of no toxicological significance. No clinical signs reporte at any dose amount. No mortality occured during the study period.
BODY WEIGHT AND WEIGHT GAIN: Body weights and body wieght gains of treated animals remained in the same range as controls over the 4-week study period.
FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Food consumption before or after allowance for body weight was similar ebtween treated and control animals.
HAEMATOLOGY: Incidental findings at 500 and/or 1000 mg/kg/day included decreased white blood cell contn (WBC), increased activated partial thromboplastin time (APTT) in males and increased red blood cell count, increased haemoglobin and haematocrit levels in females at the end of treatment. In addition, a slightly decreased red blood cell distrubution width (RDW) was noted at the end of recovery in females at 1000 mg/kg/day. These findings occured in the absence of a dose related distribution and all values were well within the physiological ranges. Therefore, these changes were considered to have arisen by chance and not to represent a chage of biological significance.
CLINICAL CHEMISTRY: Incidental findings included increased sodium levels in males and females at 250, 500 and/or 1000 mg/kg/day. Decreased aspartate aminotransferase (ASAT) level was noted in females at 1000 mg/kg/day at the end of treatment and at the end of recovery period. Slightly decreased albumin level, increased glucose, potassium and inorganic phosphate levels were noted in males at 1000 mg/kg/day at the end of recovery. These findings occured in the absence of a dose related distribution and/or occured only at the end of the recovery phase. The slight decrease of ASAT occurred at 1000 mg/kg/day at the end of treatment and at the end of the recovery phase. All levels were within the physiological range. A decrease of ASAT is occasionally seen and it is known that a decrease of ASAT is not related to organ dysfunction. All these changes are therefore considered to be of no toxicological significance.
NEUROBEHAVIOUR: Hearing ability, pupillary reflex, static righting reflex and grip strength were normal in all animals. The variation in motor activity did not indicate a relation with treatment.
ORGAN WEIGHTS: Changes were noted in absolute and relative adrenal weights of males at 250 and 500 mg/kg/day at the end of treatment and at 1000 mg/kg/day at the end of recovery only. No dose related distribution was noted and all absolute and relative adrenal weights were well within the physiological range. Moreover, no histopatholological eviddence of organ dysfunction was noted. Therefore this finding was considered not to be a sign of toxicity. Statistically significant increase was noted in relative spleen weight of males at 500 mg/kg/day (absoulte spleen weight was only slightly increased). No change in spleen weight was noted at the hgihest dose level (1000 mg/kg/day) and values at 500 mg/kg/day were withinthe physiological range. Therefore, this finding was considered not to be a sign of toxicity.
GROSS PATHOLOGY: Incidental findings among control and treated animals included pelvic dilation in the kidney, discoloration of the thymus, foci on the thymus and enlarged mandibular lymph nodes. These findings are occasioanlly seen among rats used in these types of studies. In the absence of correlated microscopic findings, these were considered changes of no toxicological significance.

Effect levels

Key result
Dose descriptor:
NOAEL
Effect level:
1 000 mg/kg bw/day (nominal)
Based on:
test mat.
Sex:
male/female
Basis for effect level:
clinical signs
mortality
body weight and weight gain
haematology
clinical biochemistry
organ weights and organ / body weight ratios
gross pathology
histopathology: non-neoplastic

Target system / organ toxicity

Key result
Critical effects observed:
no

Applicant's summary and conclusion

Conclusions:
There were no changes at determination of clinical appearance, performance of functional observations, body weight and food consumption measurements, or alterations during clinical laboratory investigations, macroscopic examination, organ weight determination and microscopic examination that were considered to be an effect of treatment. From the results presented in this report, a definitive No Observed Adverse Effect Level (NOAEL) for the test article of 1000 mg/kg/day was established.
Executive summary:

This study evaluated the potential toxicity of the test material when administered at 250, 500 and 1000 mg/kg by oral gavage to male and female Sprague Dawley rats once daily for 28 days following OECD Guideline No. 407 (1995). The test substance was administered neat. Animals (5/sex/treatment) were administered Milli U water (control), 250, 500 and 1000 mg/kg doses of the test substance by oral gavage once daily for 28 days. Recovery groups of 5 animals/sex/treatment (vehicle and 1000 mg/kg groups only) were dosed concurrently with the main dose groups and observed for an additional 14 days (recovery period) after the end of the treatment phase. Clinical observations were recorded for all animals daily for 28 days and through the recovery period for those animals. During week 4, all animals were evaluated for hearing, pupillary reflex, static righting reflex, grip strength and motor activity. Body weights and feed consumption were recorded weekly. At the end of the treatment and recovery phases, blood was collected from animals (fasted maximum of 20 hours) via the abdominal aorta for hematology and clinical chemistry. A gross necropsy was performed on all animals following euthanasia. Tissues were collected for histopathological evaluation and specific organ weights were recorded. No abnormalities were observed in any parameter analyzed for any dose group throughout the study. In conclusion based on the results of this study, the no-adverse-effect-level (NOAEL) of the test article was 1000 mg/kg by oral gavage in male and female Sprague Dawley rats.