OF THE
TIMES
evidence suggests that some environmental agents may initiate or promote cancer by disrupting normal immune and endocrine system functions. The burgeoning number and complexity of known or suspected environmental carcinogens compel us to act to protect public health, even though we may lack irrefutable proof of harm.
Chlorine dioxide: May decompose explosively on shock, friction or concussion, or on heating rapidly. Strong oxidant - reacts violently with combustible and reducing materials, and with mercury, ammonia, sulphur and many organic compounds.For more information, please visit our forum discussion.
A strong irritant of the skin, eyes, and respiratory tract; A strong oxidizer that promotes combustion; Concentrated solutions may be corrosive to the skin and eyes; Mild hemolytic anemia and increased methemoglobin in males is observed in animal feeding studies.
Acute Health Effects:
Ingestion: Not a normal route of exposure. Harmful if swallowed. Can cause irritation to mouth, esophagus, stomach, and mucous membranes.
Eye Contact: Contact causes redness, irritation, pain, blurred vision, tearing, corneal injury and burns.
Inhalation: Harmful if inhaled. Coughing, headaches, labored breathing, nausea, shortness of breath, pulmonary edema.
Chronic Health Effects: May have effects on lungs, resulting in chronic bronchitis and permanent lung damage (with chronic exposure).

Comment: There was another related report about freak snowing in Antarctica nearly two years ago:
Something Strange is Happening at the Coldest, Driest Place on Earth