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Toxicological information

Repeated dose toxicity: oral

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Administrative data

Endpoint:
sub-chronic toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1992
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 408 (Repeated Dose 90-Day Oral Toxicity in Rodents)
Deviations:
yes
Remarks:
Animals were not observed daily after week 4 and histopathology was carried out on a limited number of organs. Additionally urinalysis and functional observations were not made because the protocol is conform to the OECD 408 guideline of 1981.
GLP compliance:
yes
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Ziram
- Lot/Batch number: 8331 AA
- Description: White powder
- Purity: 98.7%
- Stability: Confirmed as 98.7%. Sample taken 1990-11-30, analysis 1991-01-04.

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Portage, Portage, Michigan, USA
- Age at study initiation: 28 days
- Weight at study initiation: 157-188 g (♂) and 117-144 g (♀)

Administration / exposure

Route of administration:
oral: feed
Vehicle:
other: diet
Duration of treatment / exposure:
13 weeks
Frequency of treatment:
daily
Doses / concentrations
Remarks:
Doses / Concentrations:
100, 300 and 1000 ppm/day. The concentration of test material in the low dose level was increased by 15% above nominal to compensate losses during storage.
Basis:
nominal in diet
No. of animals per sex per dose:
10
Control animals:
yes, plain diet
Positive control:
No

Examinations

Observations and examinations performed and frequency:
CLINICAL SIGNS
- Once daily on working days for the first four weeks, then once weekly.

MORTALITY
- Twice daily.

BODY WEIGHT
- On allocation, day 0 and then once weekly.

FOOD CONSUMPTION
- Once daily

FOOD EFFICIENCY
- Where appropriate, calculation from bodyweight and food consumption.

COMPOUND INTAKE
- Group mean was calculated weekly from group mean bodyweight, food consumption data and dietary inclusion levels of the test material.
WATER CONSUMPTION
- Once daily

OPHTHALMOSCOPIC EXAMINATION:
- For control and high-dose animals at pre-test and during week 13.

HAEMATOLOGY:
- During week 13.
- Parameters: haematocrit, erythrocyte count, haemoglobin, mean corpuscular volume, mean corpuscular haemoglobin concentration, platelet count, total leukocyte count, differential leukocyte count, cell morphology, thrombotest

CLINICAL CHEMISTRY:
- During week 13.
- Parameters: glucose, blood urea nitrogen, creatinine, total bilirubin, total cholesterol, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, calcium, phosphorus, sodium, potassium, chloride, albumin, total protein, albumin/globulin ratio

Sacrifice and pathology:
ORGAN WEIGHTS
- Brain, heart, liver, spleen, thyroid, kidneys, adrenals, uterus, testes, pituitary, ovaries

GROSS PATHOLOGY:
- All dose groups.

HISTOPATHOLOGY:
- The following tissues were removed from all animals and preserved in buffered 10% formalin (except eyes: Davidson’s fixative):
adrenals, aorta, brain (medullary, cerebellar, cortical sections), caecum, colon, duodenum, eyes, femur (with joint), Harderian gland, head (nasal cavity, paranasal sinuses, oral cavity, nasopharynx, middle ear, teeth, lachrymal gland, Zymbal’s gland), heart, ileum, jejunum, kidneys, larynx, liver, lungs (all lobes and mainstem bronchi), lymph nodes (cervical, mesenteric), mammary glands, oesophagus, ovaries, pancreas, pharynx, pituitary, prostate, rectum, salivary glands, sciatic nerve, seminal vesicles, skeletal muscle, skin, spinal cord (cervical, thoracic, lumbar), spleen, sternum, stomach, testes with epididymides, thymus, thyroid/parathyroid, tongue, trachea, urinary bladder, uterus (corpus, cervix), vagina and other macroscopically abnormal tissues
Statistics:
All analyses were carried out separately for male and female.
Data relating to food and water consumption were analysed on a cage basis. All other parameters were carried out using the individual animal as basis.
Histopathological findings were analysed using Fisher’s exact analysis.
The following tests were used for food and water consumption, bodyweight, relative organ weight and clinical pathology data:
- If the data consisted predominantly of one particular value (relative frequency of the mode exceeds 75%), the proportion of animals with values different from the mode was analysed by appropriate methods. Otherwise:
- Bartlett’s test was applied to test for heterogeneity of variance between treatments. Where significant (at the 1% level) heterogeneity was found, a logarithmic transformation was tried to see if a more stable variance structure could be obtained.
- If no significant heterogeneity was detected (or if a satisfactory transformation was found), a one-way analysis of variance was carried out. If significant heterogeneity of variance was present, and could not be removed by a transformation, the Kruskal-Wallis analysis of ranks was used.
- Except for pre-dose data, analyses of variance were followed by Student’s ‘t’ test and Williams’ test for a dose-related response, although only the one thought most appropriate for the response pattern observed has been reported. The Kruskal-Wallis analyses were followed by the non-parametric equivalents of the ‘t’ test and Williams’ test (Shirleys’ test).
Where appropriate, during absolute organ weight analysis, analysis of covariance was used in place of analysis of variance.

Results and discussion

Results of examinations

Clinical signs:
effects observed, treatment-related
Mortality:
mortality observed, treatment-related
Body weight and weight changes:
effects observed, treatment-related
Food consumption and compound intake (if feeding study):
effects observed, treatment-related
Food efficiency:
no effects observed
Water consumption and compound intake (if drinking water study):
no effects observed
Ophthalmological findings:
no effects observed
Haematological findings:
effects observed, treatment-related
Clinical biochemistry findings:
effects observed, treatment-related
Urinalysis findings:
not examined
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:
effects observed, treatment-related
Histopathological findings: neoplastic:
not examined
Details on results:
CLINICAL SIGNS
Slightly higher incidence of hair loss in males/females given 300 and 1000 ppm. Not apparent among controls or low-dose group and not confirmed at post mortem examination.

MORTALITY
One control female during week 13. Examinations revealed congestion in the lungs, the smell of ether in the thoracic cavity and a pale subcapsular area on the median liver-lobe.

BODY WEIGHT AND WEIGHT GAIN
Dosage-dependent reduction among males and females at 300 and 1000 ppm during week 1. At the dosage of 1000 ppm trend continued though less markedly.

FOOD CONSUMPTION
Dosage-related reduced among males and females given 300 and 1000 ppm during week 1. At 1000 ppm trend continued to a lesser degree.

COMPOUND INTAKE
Means over the treatment period are:
7.4, 21.4, 67.8 mg/kg bw/day for males
8.8, 24.2, 76.9 mg/kg bw/day for females

HAEMATOLOGY
Significant decrease in mean RBC (red blood cell) values for animals given 1000 ppm. Corresponding increases in mean corpuscular haemoglobin concentration (MCHC) values were also noted.

CLINICAL CHEMISTRY
Urea nitrogen increase in animals given 1000 ppm and females given 100 and 300 ppm.
Dosage-related decrease in total protein in females, mainly due to reduction in albumin, and a lowering in serum calcium in all treated groups.
Increase in serum alkaline phosphatase (AP) in females given 1000 ppm.

ORGAN WEIGHTS
Higher brain weight in animals given 300 or 1000 ppm. In addition higher spleen weights were apparent for rats given 1000 and females given 300 ppm. Greater testes and ovary weights were also noted at 1000 ppm.

HISTOPATHOLOGY: NON-NEOPLASTIC
Stomach: Minimal epithelial hyperplasia of the non-glandular stomach was observed in animals given 1000 and one female given 300 ppm. Because of lacking significance according to Fisher’s exact analysis the effect was considered to be of no toxicological relevance.

Effect levels

open allclose all
Dose descriptor:
LOAEL
Effect level:
ca. 7.4 mg/kg bw/day (nominal)
Sex:
male/female
Basis for effect level:
other: Decrease in serum calcium and blood proteins and increase in urea nitrogen
Dose descriptor:
NOAEL
Effect level:
< 7.4 mg/kg bw/day (nominal)
Sex:
male/female

Target system / organ toxicity

Critical effects observed:
not specified

Any other information on results incl. tables

Table 7.5.1 -B1 Oral 90 day toxicity in rats by ziram

Endpoint / Dose

Control

100 ppm

300 ppm

1000 ppm

Dose-response

+/–

Mortality

1

Clinical signs

hairloss

Food consumption

↓ 13%

↓ 17%

↓ 25%

↓ 25%

+

+

Food efficiency

Impaired

week 1

+

Body weight gain

↓ 18%

↓ 18%

↓ 33%

↓ 32%

+

+

Haematology

RBC

+

+

MCHC

+

+

Blood chemistry

Urea nitrogen

+

+

Total protein

+

Serum Ca2+

+

Serum AP

+

Organ weight

Brain

Spleen

+

+

Testes or ovary

↑, ↓: statistically significant increase and decrease, respectively

Applicant's summary and conclusion