Reaction mass of Di-μ-thio-[{bis(2-ethylhexyl)carbamato-S,S’}oxo molybdenum(V)], Di-μ-thio-[{(2-ethylhexyl)carbamato-S,S’}{(branched ditridecyl)carbamato-S,S’}oxo molybdenum(V)] and Di-μ-thio-[{bis(branched ditridecyl)carbamato-S,S’}oxo molybdenum(V)]

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20th August to 06 December 1999

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was conducted in a GLP compliant laboratory according to accepted regulatory guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 407 (Repeated Dose 28-Day Oral Toxicity Study in Rodents)

Version / remarks:

Annex V (Repeat dose toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

other: The japanese Ministry of Health and Welfare (MHW) Guidelines 1986 for a twenty-eight day repeat dose oral toxicity study as required by japanese Chemical Substances Control Law 1973 of the Ministry of International Trade and Industry (MITI) amended 1986

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method B.7 (Repeated Dose (28 Days) Toxicity (Oral))

Deviations:

no

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

S-900

IUPAC Name:

S-900

Test material form:

semi-solid (amorphous): gel

Remarks:

migrated information: paste

Details on test material:

- Name of test material (as cited in study report): S-900
- Physical state: dark brown paste
- Analytical purity: 98.72%
- Lot/batch No.: 02869
- Storage condition of test material: room temperature, in the dark
- Other:

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: reputable commercial supplier
- Age at study initiation: 5-7 weeks
- Weight at study initiation: 127-160g (males); 128-159g (females)
- Fasting period before study: fasted overnight during urine collection
- Housing: The animals were housed in groups of five by sex in polypropylene grid-floor cages suspended over trays lined with absorbent paper.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 ± 2 C
- Humidity (%): 55 ± 15%
- Air changes (per hr): ca 15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12h light: 12h dark

IN-LIFE DATES: From: To: 13th September to 26th October 1999

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

arachis oil

Details on oral exposure:

Method of administration:
Oral gavage

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

Test duration: 28 days

Frequency of treatment:

daily for 28 consecutive days

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

15 mg/kg bw/day (actual dose received)

Doses / concentrations 2

Dose / conc.:

150 mg/kg bw/day (actual dose received)

Doses / concentrations 3

Dose / conc.:

1 000 mg/kg bw/day (actual dose received)

No. of animals per sex per dose:

Male: 5+5 animals at 0 mg/kg bw/day (one 14-day recovery group)
Male: 5 animals at 15 mg/kg bw/day
Male: 5 animals at 150 mg/kg bw/day
Male: 5+5 animals at 1000 mg/kg bw/day (one 14-day recovry group)
Female: 5+5 animals at 0 mg/kg bw/day (one 14-day recovery group)
Female: 5 animals at 15 mg/kg bw/day
Female: 5 animals at 150 mg/kg bw/day
Female: 5+5 animals at 1000 mg/kg bw/day (one 14-day recovery group)

Control animals:

yes, concurrent vehicle

Details on study design:

- Dose selection rationale:The dose levels were chosen based on the results of the range-finding study presented in this report.
- Rationale for animal assignment (if not random): random
- Rationale for selecting satellite groups:
- Post-exposure recovery period in satellite groups: 14 days
- Section schedule rationale (if not random): random

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: Yes
- Time schedule:twice daily, morning and afternoon (once daily) at weekends

DETAILED CLINICAL OBSERVATIONS: Yes
- Time schedule:immediately before dosing and one and five hours after dosing wherever possible during the working week. Animals were observed immediately before dosing and one hour after dosing at weekends.

BODY WEIGHT: Yes
- Time schedule for examinations: Individual bodyweights were recorded on Day 0 (the day before the start of treatment) and on Days 7, 14, 21 and 28 and, in the case of recovery group animals, on Days 35 and 42. Bodyweights were also recorded at terminal kill



HAEMATOLOGY: Yes
- Time schedule for collection of blood:Haematological and blood chemical investigations were performed on all nonrecovery test and control group animals at the end of the treatment period (Day 28) and on all recovery group animals at the end of the treatment-free period (Day 42)
- Anaesthetic used for blood collection: No
- Animals fasted: No
- How many animals: as above

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: see details for haematology


URINALYSIS: Yes
- Time schedule for collection of urine: Urinalytical investigations were performed on all non-recovery test and control group animals during Week 4 and on all recovery group animals during Week 6.
- Metabolism cages used for collection of urine: Yes
- Animals fasted: Yes

NEUROBEHAVIOURAL EXAMINATION: Yes
-On one occasion prior to the start of treatment and on Days 6, 13, 20 and 23 all animals were observed for signs of functional/behavioural toxicity. On Days
23 and 24 functional performance tests were also performed on all animals whilst an assessment of sensory reactivity to different stimuli was performed on
all animals on Day 23. Observations were carried out from approximately two hours after dosing on each occasion.

OTHER:

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
The following organs removed from animals that were killed either at the end of the dosing period or at the end of the treatment-free period, were
wherever possible dissected free from fat and weighed before fixation:
Adrenals
Kidneys
Testes
Brain
Liver
Thymus
Epididymides
Ovaries
Heart
Spleen


HISTOPATHOLOGY: Yes

Statistics:

Data were processed to give group mean values and standard deviations where appropriate.
Haematological, blood chemical, organ weight (absolute and relative to terminal bodyweight), weekly bodyweight gain and quantitative urinalytical, functional performance and sensory reactivity data were assessed for dose response relationships by linear regression analysis followed by one way analysis of variance (ANOVA) incorporating Levene's test for homogeneity of vanance. Where variances were shown to be homogenous, pairwise comparisons were conducted using Dunnett's test. Where Levene's test showed unequal variances the data were analysed using non-parametric methods: Kruskal-Wallis ANOVA and MannWhitney "U" test.
The haematology variable basophils was not analysed since consistently greater
than 30% of the data were recorded as the same value.

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

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:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

Clinical observations:
There were no deaths during the study.

No clinically observable signs of toxicity were detected
during the study.

Increased salivation either before or up to ten minutes
aftre dosing and up to one hour after dosing together with
isolated incidents of red/brown staining of the external
body surface were detected from Day 9 onwards among animals
of either sex treated with 1000 mg/kg/day. Such signs often
accompany the oral administration of a test material
formulation and are considerd attributable to an unpleasant
tasting or locally irritating formulation rather than an
indication of systemic toxicity.


Functional Observations:

No treatment-related behavioural differences were detected.


Body Weight:

No adverse effect on bodyweight developed was detected.

Females treated with 1000 mg/kg/day showed a slight but
statistically significant reduction in bodyweight gain
during Week 1 of the study when compared with controls. The
level of significance acheived was minimal and in the
absence of any impact on subsequent bodyweight development
or indeed further toxicological changes, this isolated
reduction was considerd to be of no toxicological
importance.


Food Consumption:

No adverse effect on dietary intake or food efficiency
detected during the study.

Laboratory findings:
Haematology:

No treatment-related haematological chemical changes were
detected.


Statistically significant intergroup differences included:
an increase in erythrocyte count in 1000 mg/kg females
arising from low control group mean; an increase in
lymphocyte count in males showing no dose response
relationship; in males among recovery 1000 mg/kg/day animals
increases in activated partial thromboplastin time.
Accordingly, these changes were considered to be of no
toxicological significance.


Blood Chemisry:

No treatment-related blood chemical changes were detected.


A number of statistically significant intergroup differences
were detected between treated animals and controls but in
the absence of any dose-response relationship and/or any
associated changes in other parameters which might indicate
target organ toxicity, these intergroup differences were
considered to be of no toxicological significance.


Urinalysis:

No treatment-releated urinalytical changes were detected.

Effects in organs:
Organ Weights:

No treatment-related organ weight changes were detected.


Statistically significant intergroup differences were
confined to recovery 1000 mg/kg/day animals and, in the
absence of any changes in the same parameters at the end of
the treatment period, were considered to be of no
toxicological importance.


Necropsy:

No treatment-related macroscopic abnormalities detected at
terminal kill.


One male treated with 100 mg/kg/day showed a small, light
patch on the right kidney at terminal kill but in the
absence of any histopathological or blood chemical
correlates, this isolated finding was considered to be of no
toxicological significance.


Histopathology:

No treatment-related microscopic abnormalities were
detected.

Effect levels

Key result

Dose descriptor:

NOEL

Effect level:

> 1 000 mg/kg bw/day (actual dose received)

Based on:

test mat.

Sex:

male/female

Remarks on result:

other: 1000 mg/kg/d was the highest dose tested

Target system / organ toxicity

Key result

Critical effects observed:

no

Applicant's summary and conclusion

Conclusions:

Repeated oral administration of the test material, S-900, to rats by gavage for a period of twenty-eight days at dose levels of up to 1000 mg/kg/day did not produce any toxicologically significant changes in the parameters measured. The "No Observed Effect Level" (NOEL) was, therefore, considered to be 1000 mg/kg/day.
Classified as: Not classified