Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Version / remarks:
2009
GLP compliance:
yes
Limit test:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
Molybdenum, bis(N,N-dibutylcarbamodithioato-κS,κS')dioxodi-μ-thioxodi-, stereoisomer
EC Number:
825-571-0
Cas Number:
60428-79-7
Molecular formula:
C18H36Mo2N2O2S6
IUPAC Name:
Molybdenum, bis(N,N-dibutylcarbamodithioato-κS,κS')dioxodi-μ-thioxodi-, stereoisomer
Test material form:
solid: particulate/powder

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Charles River Deutschland, Germany
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: approx. 10 weeks
- Weight at study initiation: 268-300 (males), 203-228 g (females)
- Fasting period before study: no
- Housing: group housing up to 5 animals per cage and sex
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-22
- Humidity (%): 49-54
- Air changes (per hr): >=
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: To:

Administration / exposure

Route of administration:
inhalation: dust
Type of inhalation exposure:
nose only
Vehicle:
air
Mass median aerodynamic diameter (MMAD):
ca. 4.3 µm
Geometric standard deviation (GSD):
ca. 2.2
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: directed flow nose only inhalation chamber
- Exposure chamber volume:
- Method of holding animals in test chamber: restraining tubes
- Source and rate of air: approx. 1 l/min at each animal port
- Method of conditioning air:
- System of generating particulates/aerosols: Wright dust feeder
- Method of particle size determination: 8 stage Marple personal cascade impactor; collected dust fraction was determined gravimetrically
- Treatment of exhaust air: passed through a filter
- Temperature, humidity, pressure in air chamber: 20.1-21.6°C, 10-12%

TEST ATMOSPHERE
- Brief description of analytical method used:
- Samples taken from breathing zone: yes/no

VEHICLE
- Composition of vehicle (if applicable):
- Concentration of test material in vehicle (if applicable):
- Justification of choice of vehicle:
- Lot/batch no. (if required):
- Purity:

TEST ATMOSPHERE (if not tabulated)
- Particle size distribution: 0.5 µm - approx. 10 µm
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): 4.3 µm, GSD 2.2

CLASS METHOD (if applicable)
- Rationale for the selection of the starting concentration:
Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
ca. 4 h
Concentrations:
5.0 +/- 0.1 mg/l
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: daily observation, weighing on days 1, 2, 4, 8, 15
- Necropsy of survivors performed: yes, macroscopic
- Other examinations performed: clinical signs, body weight

Results and discussion

Effect levels
Key result
Sex:
male/female
Dose descriptor:
LC0
Effect level:
>= 5 mg/L air
Based on:
test mat.
Exp. duration:
4 h
Mortality:
no
Clinical signs:
other: after exposure, hunched posture and yellow staining (general) were seen for all animals between Days 1 and 4.
Body weight:
body weight loss was noted for all animals, this continued for three females up to Day 8, the animals regained weight during the second week.
Gross pathology:
no abnormalities observed

Applicant's summary and conclusion

Interpretation of results:
other: no death at limit concentration