methyl (2E)-[2-(chloromethyl)phenyl](methoxyimino)acetate

Repeated dose toxicity: oral

Administrative data

Endpoint:

sub-chronic toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study with GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Remarks:

BASF AG, Experimental Toxicology and Ecology

Limit test:

no

Test material

Reference

Name:

Unnamed

Type:

Constituent

Details on test material:

- Name of test material (as cited in study report): 520 F-Chlormethyloximether
- Physical state: solid/ dark green
- Analytical purity: 96.8%
- Lot/batch No.: 31196-182
- Storage condition of test material: room temperature

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH
- Age at study initiation: 42 ± 1 days
- Weight at study initiation:
- Housing: 5 per cage
- Diet (e.g. ad libitum): Kliba maintenance diet
- Water (e.g. ad libitum): drinking water (from water bottles)
- Acclimation period: 7 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: feed

Details on oral exposure:

DIET PREPARATION
- For each concentration, the test substance was weighed out and mixed with a small amount of food. Then corresponding amounts of food, depending on test group, were added to this premix in order to obtain the desired concentrations. Mixing was carried out for about 10 minutes in a laboratory mixer.
- Rate of preparation of diet (frequency): every 4 weeks

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Mean values of 520 F-Chlormethyloximether in Kliba lab diet were found to be in the range of 97.7 – 108.2% of the nominal concentration.

Duration of treatment / exposure:

90 days

Frequency of treatment:

continously, 7 days/week

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 250, 1250 and 5000 ppm (males); 0, 250, 1250 and 2500 ppm (females)
Basis:
nominal in diet

No. of animals per sex per dose:

10

Control animals:

yes, concurrent no treatment

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- A check for moribund and dead animals was made twice daily on working days and once daily on Saturdays, Sundays and public holidays. If animals were in a moribund state, they were sacrificed and necropsied. All animals were checked daily for any clinically abnormal signs.


DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule: prior to the administration period (day 0) and thereafter at weekly intervals
- The following parameters were examined: abnormal behavior during “handling”, fur, skin, posture, salivation, respiration, activity/arousal level, tremors, convulsions, abnormal movements, impairment of gait, lacrimation, palpebral closure, exophthalmus, feces (appearance/consistency), urine, pupil size


BODY WEIGHT: Yes
- Time schedule for examinations: day 0 (start of the administration period) and thereafter at weekly intervals


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: Yes
- Compound intake calculated as time-weighted averages from the consumption and body weight gain data: Yes


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: Yes


WATER CONSUMPTION AND COMPOUND INTAKE (if drinking water study): Yes
- Time schedule for examinations: daily (Group water consumption)


OPHTHALMOSCOPIC EXAMINATION: Yes
- Time schedule for examinations: prior to the start of the administration period and on day 90
- Dose groups that were examined: control and high dose groups


HAEMATOLOGY: Yes
- Time schedule for collection of blood: at the termination of the experiment
- Anaesthetic used for blood collection: Yes (isoflurane)
- Animals fasted: Yes
- How many animals: all
- Parameters checked: Leukocyte count (WBC), Erythrocyte count (RBC), Hemoglobin (HGB), Hematocrit (HCT), Mean corpuscular volume (MCV), Mean corpuscular hemoglobin (MCH), Mean corpuscular hemoglobin concentration (MCHC), Platelet count (PLT), Differential blood count, Reticulocytes and Prothrombin time.


CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the termination of the experiment
- Animals fasted: Yes
- How many animals: all
- Parameters checked: Alanine aminotransferase (ALT), Aspartate aminotransferase (AST), Alkaline phosphatase (ALP), γ-Glutamyltransferase (GGT), Sodium (NA), Potassium (K), Chloride (CL), Inorganic phosphate (INP), Calcium (CA), Urea (UREA), Creatinine (CREA), Glucose, Total bilirubin, Total protein, Albumin, Globulins, Triglycerides, Cholesterol, Magnesium


URINALYSIS: Yes
- Time schedule for collection of urine: during 13th week
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes
- Parameters checked: pH, protein, Glucose, Ketones, Urobilinogen, Bilirubin, Blood, Specific gravity, Sediment, color, turbidity, volume


NEUROBEHAVIOURAL EXAMINATION: Yes
- Time schedule for examinations: at the end of the administration period
- Dose groups that were examined: all
- Battery of functions tested: sensory activity [approach response, touch response, vision ("visual placing response"), pupillary reflex, pinna reflex, audition ("startle response"), coordination of movements ("righting response"), behavior during "handling", vocalization, pain perception ("tail pinch"), grip strength of forelimbs, grip strength of hindlimbs, landing foot-splay test] / grip strength / motor activity (examinations were performed using the TSE Labmaster System) / other: home cage observations [Attention was paid to posture, tremor, convulsions, abnormal movements, impairment of gait]; Open field observations [behavior when removed from cage, fur, skin, salivation, nose discharge, lacrimation, eyes/pupil size, posture, palpebral closure, respiration, tremors, convulsions, abnormal movements, impairment of gait, activity/arousal level, feces (number of fecal pellets/appearance/consistency) within two minutes, urine (appearance/quantity) within two minutes, number of rearings within two minutes].

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: Yes
The following organs or tissues were fixed in 4% formaldehyde solution: All gross lesions, Brain, Pituitary gland, Thyroid glands, Parathyroid glands, Oesophagus, Salivary glands (mandibular and sublingual glands), Trachea, Lungs, Pharynx, Larynx, Nose (nasal cavity), Thymus, Aorta, Heart, Liver, Pancreas, Spleen, Kidneys, Adrenal glands, Oviducts, uterus and vagina, Prostate and seminal vesicles including coagulation glands, Stomach (forestomach and glandular stomach), Duodenum, jejunum and ileum, Cecum, colon and rectum, Urinary bladder, Lymph nodes (mesenteric and axillary lymph nodes), Sciatic nerve, Bone marrow (femur), Eyes, Extraorbital lacrimal glands, Skin, Female mammary gland, Spinal cord (cervical, thoracic and lumbar cords), Sternum with marrow, Femur with knee joint, Skeletal muscle

Other examinations:

Organ weights were determined from anesthetized animals, Liver, Kidneys, Adrenal glands, Testes, Epididymides, Cauda epididymides, Ovaries, Uterus, Prostate, Seminal vesicles including coagulation glands, Spleen, Brain, Heart, Thymus, Thyroid glands.

Statistics:

- Body weight, body weight change: A comparison of each group with the control group was performed using DUNNETT's test (two-sided) for the hypothesis of equal means.
- feces, rearing, grip strength forelimbs, grip strength hindlimbs, footsplay test, motor activity, Clinical pathology parameters, urine volume, urine specific gravity: Non-parametric oneway analysis using KRUSKAL-WALLIS test (two-sided)
- Urinalysis, except color, turbidity, volume and specific gravity- Pairwise comparison of each test group with the control group using FISHER's exact test for the hypothesis of equal proportions

Results and discussion

Results of examinations

Details on results:

CLINICAL SIGNS AND MORTALITY: no mortality or clinical signs were observed.


BODY WEIGHT AND WEIGHT GAIN: Body weight (-11.7% on day 91) as well as body weight change (-20.5% on day 91) were significantly impaired only in the male animals of high dose group (5000 ppm) throughout the whole study period.


FOOD CONSUMPTION AND COMPOUND INTAKE (if feeding study): No substance-related changes in food consumption were observed. The approximate mean daily test-substance intake in mg/kg bw/day in males of the 250, 1250 and 5000 ppm dose groups were 16.2, 77.6 and 326.3, respectively. The approximate mean daily test-substance intake in mg/kg bw/day in females of the 250, 1250 and 2500 ppm dose groups were 18.3, 93.4 and 191.3, respectively.


FOOD EFFICIENCY: Significant changes in food efficiency were measured on some isolated days in all treated animals over the whole study period. Due to the lack of a dose-response relationship, no clear substance related influence was observed.


WATER CONSUMPTION: No substance-related changes in water consumption were observed


OPHTHALMOSCOPIC EXAMINATION: All findings were incidental in nature, due to the occurrence in single animals, only, and/or the lack of a dose-response relationship


HAEMATOLOGY: At the study end in male rats of the 5000 ppm test group the hemoglobin concentrations and the hematocrit values were higher compared to the controls. No other substance-related findings were observed.


CLINICAL CHEMISTRY: No treatment-related adverse effects were observed concerning the clinical chemistry parameters.


URINALYSIS: No treatment-related adverse effects were observed


NEUROBEHAVIOUR: No substance-related findings were observed.


REPRODUCTIVE FUNCTION: ESTROUS CYCLE: No substance-related effects were observed.


REPRODUCTIVE FUNCTION: SPERM MEASURES: There were no treatment-related changes in the sperm parameters measured.


ORGAN WEIGHTS: The only treatment-related effect observed was decrease of the terminal body weight in the 5000 ppm group males (88 % in comparison to controls)


GROSS PATHOLOGY: incidentally as single cases were reported which were not substance-related findings.


HISTOPATHOLOGY: NON-NEOPLASTIC: no substance-related findings were observed

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

ca. 77.6 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male

Basis for effect level:

other: reduced body weight and body weight change, and increased hemoglobin and hematocrit values

2

Dose descriptor:

NOAEL

Effect level:

ca. 191.3 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

female

Basis for effect level:

other: no effects

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

The oral administration of 520 F-Chlormethyloximether via the diet over a period of 3 months caused signs of general systemic toxicity only in male animals of the 5000 ppm group as indicated by a reduced body weight and body weight change as well as increased hemoglobin and hematocrit values. No other substance-related adverse findings were observed, neither in mid and low dose males nor in females throughout all concentrations tested. Therefore, the no observed adverse effect level (NOAEL) under the conditions of this study was 1250 ppm in male (about 77.6 mg/kg bw/day) and 2500 ppm in female (about 191.3 mg/kg bw/day) Wistar rats.

The oral administration of 520 F-Chlormethyloximether via the diet over a period of 3 months caused no adverse effects on the fertility parameters in both males and females up to be the highest dose tested.