Hydrogen fluoride health effects

TABLE 8.5.3 Predicted Effects on Human Health of Exposure to Various Concentrations of Hydrogen Fluoride ... 

Note to the definition of immediately dangerous to life or health Some materials—hydrogen fluoride gas and cadmium vapor, for example—may produce immediate transient effects that, even if severe, may pass without medical attention, but are followed by sudden, possibly fatal collapse 12-72 hours after exposure. The victim feels normal from recovery from transient effects until collapse. Such materials in hazardous quantities are considered to be immediately dangerous to life or health. 

Hydrogen fluoride is a hazardous air pollutant that is a highly corrosive and systemic poison that causes severe and sometimes delayed health effects due to deep tissue penetration. Absorption of substantial amounts of hydrogen fluoride by any route may be fatal (ASTDR, 2011). One of the hydraulic fracturing companies used 67,222 gal of two products containing hydrogen... 

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