Registration Dossier

Administrative data

Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Study period:
December 5 1984 - December 21 1984
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study performed to GLP and conducted according to the requirements of a guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985
Report Date:
1985

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Sodium dichloroisocyanurate
- Lot/batch No.: 8/84-811 and 8/84-811-2

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Charles River Breeding Laboratories, portage, MI
- Diet: Purina certified rodent chow 5002 ad libitum except during exposure
- Water: ad libitum except during exposure, via an automated watering system
- Acclimation period: 7 days


ENVIRONMENTAL CONDITIONS
- Photoperiod: 12 hours light/12 hours dark


Administration / exposure

Route of administration:
inhalation: dust
Type of inhalation exposure:
whole body
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Stainless steel and glass inhalation chamber
- Exposure chamber volume: 500 L
- System of generating particulates/aerosols: The test atmosphere dust was generated by passing a stream of air through the test article contained in a dust shaker mechanism
- Method of particle size determination: Particle size determination was conducted using a Delron Cascade Impactor, Model No. DCI-6. A sample was collected at approximately 1 and 3 hours during the exposure.
- Temperature, humidity, pressure in air chamber: 0.27 mg/L exposure chamber: Mean temp: 75.4°F, Mean % relative humidity: 40.9, barometric pressure = 29.96 inches Hg. 1.17 mg/L exposure chamber: Mean temp: 69.2°F, Mean % relative humidity: 41.1, barometric pressure = 29.75 inches Hg



TEST ATMOSPHERE
- MMAD (Mass median aerodynamic diameter) / GSD (Geometric st. dev.): Mean values for MMAD and GSD for the test atmospheres were 1.93 µm and 2.44 respectively.



Duration of exposure:
4 h
Concentrations:
Gravimetric concentrations 0.27 and 1.17 mg/L
Nominal concentrations: 3.3 and 12.4 mg/L
No. of animals per sex per dose:
5
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations with respect to mortality and reactions were recorded at least every 60 minutes during the exposure. Animals were observed at least twice daily during the 14 day observation period for mortality and once daily for reactions. Each animal was weighed prior to exposure, on the 7th and 14th days of the observation period or at death.
- Necropsy of survivors performed: yes. Necropsy examination included the following: external and internal portions of all hollow organs; cranial cavity and external surfaces of the brain and spinal cord; nasal cavity and paranasal sinuses; neck with associated organs and tissues; thoracic, abdominal and pelvic cavities with their associated organs and tissues; and muscular/skeletal carcass. The specific condition of the nasal passages, trachea, liver, kidneys, bronchi and lungs were recorded.

Results and discussion

Effect levels
Sex:
male/female
Dose descriptor:
LC50
Effect level:
> 0.27 - < 1.17 mg/L air
Exp. duration:
4 h
Remarks on result:
other: measured gravimetrically
Mortality:
None of the 0.27 mg/L animals died during the study while 6 of the 10 1.17 mg/L animals died.
Clinical signs:
other: Irregular breathing, salivation, squinting, prostration, lethargy, crusty eye, crusty muzzle, crusty nose, alopecia, scab, opacity of the eye, yellow / brown fur, gasping and poor coat quality were observed among test animals
Body weight:
All but one of the surviving animals exhibited body weight gains during the study period.
Gross pathology:
No gross lesions were noted in any of the 0.27 mg/L rats. Abnormalities of the skin, ear, lungs, liver, brain, feet, abdominal cavity, small intestine, external nares and glandular stomach.

Applicant's summary and conclusion

Interpretation of results:
not classified
Remarks:
Migrated information see conclusion
Conclusions:
Under the conditions of the study the LC50 for sodium dichloroisocyanurate would be less than the gravimetric concentration of 1.17 mg/L and greater than the gravimetric concentration of 0.27 mg/L. . However only a small percentage of the active material in commerce is respirable or inhalable, as most of the commercial product is marketed in grnaular or tableted forms which have much larger particle sizes.
In the study the test material was ground to form a respirable powder. Therefore, the result from the inhalation study is not applicable for classification and labelling and due to the minimal potential for inhalation presented by the marketed active substance, the inhalation route will not be considered for hazard identification.