Frostbite effects are a change in color of the skin to gray or white, possibly followed by blistering. Skin may become inflamed and painful. Ingestion is unlikely. Carbon dioxide is the most powerful cerebral vasodilator known. Inhaling large concentrations causes rapid circulatory insufficiency leading to coma and death.
Asphyxiation is likely to occur before the effects of carbon dioxide overexposure.
Chronic, harmful effects are not known from repeated inhalation of low concentrations. Low concentrations of carbon dioxide cause increased respiration and headache. As asphyxiation progresses, nausea, vomiting, prostration, and loss of consciousness may result, eventually leading to convulsions, coma, and death. Oxygen deficiency during pregnancy has produced developmental abnormalities in humans and experimental animals. Severe Hazard 4.