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Toxicological information

Repeated dose toxicity: oral

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Administrative data

Endpoint:
sub-chronic toxicity: oral
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
not stated
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Valid with restrictions including lack of biochemical investigations and limited reporting of statistical findings. Study reasonably well documented, meets generally accepted scientific principles, acceptable for assessment.
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1966
Report Date:
1966

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Rats treated via the diet for 90 days with limited evaluation
GLP compliance:
no
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent

Test animals

Species:
rat
Strain:
other: albino
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Breeding Laboratories Inc.
- Age at study initiation: no data but "young"
- Weight at study initiation: males 104.1 g, females 90.5 g
- Fasting period before study: no data
- Housing: individually in suspended wire-mesh cages
- Diet (e.g. ad libitum): Purina Laboratory Chow, ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data but "controlled within narrow limits"
- Humidity (%): no data but "controlled within narrow limits"
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

IN-LIFE DATES: no data

Administration / exposure

Route of administration:
oral: feed
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
DIET PREPARATION
- Rate of preparation of diet (frequency): weekly
- Mixing appropriate amounts with (Type of food): basal laboratory diet (Purina Laboratory Chow)
- Storage temperature of food: no data
Analytical verification of doses or concentrations:
no
Duration of treatment / exposure:
13 weeks
Frequency of treatment:
continuous in diet
Doses / concentrations
Remarks:
Doses / Concentrations:
1%, 2.5%, 5-10%
Basis:
nominal in diet
No. of animals per sex per dose:
10 (treated), 20 (controls)
Control animals:
yes, plain diet
Details on study design:
- Dose selection rationale: no data
- Rationale for animal assignment (if not random): no data
- Rationale for selecting satellite groups: no satellite groups
Positive control:
none

Examinations

Observations and examinations performed and frequency:
CAGE SIDE OBSERVATIONS: Yes
- Time schedule: 5 days/week
- Cage side observations included: general physical appearance, gross signs of systemic toxicity and/or pharmacological effect, behaviour, mortality

DETAILED CLINICAL OBSERVATIONS: No

BODY WEIGHT: Yes
- Time schedule for examinations: weekly

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): Yes
- Time schedule for examinations: weekly
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: Yes
- Compound intake calculated as mg/kg bw/day: Yes

FOOD EFFICIENCY: No

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: days 30 and 90
- Anaesthetic used for blood collection: No data
- Animals fasted: No data
- How many animals: 5/sex per group
- Parameters examined: microhaematocrit, haemoglobin, total and differential leukocyte count

CLINICAL CHEMISTRY: No

URINALYSIS: Yes
- Time schedule for collection of urine: days 30 and 90
- Metabolism cages used for collection of urine: No data
- Animals fasted: No data
- How many animals: 5/sex per group (samples pooled)
- Parameters examined: albumin, acetone, bilirubin, colour, occult blood, sugar, pH, appearance, microscopic examination of sediment

NEUROBEHAVIOURAL EXAMINATION: No
Sacrifice and pathology:
GROSS PATHOLOGY: Yes

ORGAN WEIGHTS: brain, thyroid, heart, liver, spleen, kidneys, adrenals, gonads (testes or ovaries)

HISTOPATHOLOGY: Yes
- brain, thyroid, parathyroid, heart, lung, liver, spleen, stomach, small intestine, large intestine, pancreas, kidney, urinary bladder, adrenal, gonad, lymph node, bone, bone marrow
- all listed tissues from 5/sex from high dose and controls examined
Other examinations:
none
Statistics:
Chi-squared test for comparing relative organ weights. Original organ weight analyses using the Chi square test were supplemented by Tukey tests carried out by the Weinberg group (see 'Any other information on materials and methods')

Results and discussion

Results of examinations

Clinical signs:
no effects observed
Mortality:
no mortality observed
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
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:
not examined
Urinalysis findings:
no effects observed
Behaviour (functional findings):
not examined
Organ weight findings including organ / body weight ratios:
effects observed, treatment-related
Gross pathological findings:
no effects observed
Histopathological findings: non-neoplastic:
no effects observed
Histopathological findings: neoplastic:
not examined
Details on results:
CLINICAL SIGNS AND MORTALITY
- all animals survived the 13 week treatment  period.
- all surviving animals appeared normal

BODY WEIGHT AND WEIGHT GAIN
- significantly reduced (84.7 - 89.8% of controls) in top dose males for most study weeks, in mid dose females at weeks 4-13 and high dose females (81.7-89.7%) throughout the study
- changes were attributed at least in part to reduced food consumption and the high content of test material in the diet.

FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study)
- significantly reduced (76.4 - 89.2% of controls) in  top dose males at weeks 1 and 12, in mid dose males at week 13, in mid dose females at week 1 and high dose females weeks 1 and 12 (79.1 - 89.9%  of controls).

FOOD EFFICIENCY
- no data

WATER CONSUMPTION
- not examined

OPHTHALMOSCOPIC EXAMINATION
- not examined

HAEMATOLOGY
- no effects

CLINICAL CHEMISTRY
- not examined

URINALYSIS
- no effects

NEUROBEHAVIOUR
- not examined

ORGAN WEIGHTS
- the original report indicated that there were significant differences in some relative organ weights from treated groups compared to controls. These were reanalysed by the Weinberg Group using the Tukey test (see 'Remarks on results' section)

GROSS PATHOLOGY
- unremarkable

HISTOPATHOLOGY: NON-NEOPLASTIC
- there were no treatment related histopathological changes in the control and top dose animals examined (including testes & ovaries). 

HISTOPATHOLOGY: NEOPLASTIC (if applicable)
- not applicable

HISTORICAL CONTROL DATA (if applicable)
- no data

Effect levels

open allclose all
Dose descriptor:
NOAEL
Effect level:
> 4 257 other: mg/kg (bw) based on highest dose tested.
Sex:
male
Basis for effect level:
other: see 'Remark'
Dose descriptor:
NOAEL
Effect level:
> 4 567 other: mg/kg (bw) based on highest dose tested.
Sex:
female
Basis for effect level:
other: see 'Remark'

Target system / organ toxicity

Critical effects observed:
not specified

Applicant's summary and conclusion

Conclusions:
In a reliable study, in which rats were treated with Alfol 16 via the diet for 13 weeks, an NOAEL of >4400 mg/kg bw/day (highest dose tested) was determined. Reduced weight gain, food consumption and organ weight changes were deemed to be secondary to the high dose administered but not specific to the test substance.