Fluoride Action Network

Hawaii: Characterization of air contaminants formed by the interaction of lava and sea water

Source: Environmental Health Perspectives 102(5):478-82. | Division of Respiratory Disease Studies, National Institute for Occupational Safety and Health, Morgantown, West Virginia
Posted on May 30th, 1994
Industry type: Volcanoes

Excerpts from article:

… We also analyzed the impinger and silicagel sorbent tubes for anions of other inorganic acids including bromide, fluoride, nitrate, perchloric, phosphate, and sulfate. Of these, fluoride, nitrate, perchloric, and sulfate were identified in some samples collected from the sampling stations within the plume. Nitric and perchloric acids were below quantifiable levels in all samples. Hydrofluoric acid (HF) was detected in 9 of 20 samples from the beach sampling stations. Four of these samples had quantifiable HF concentrations; these samples were collected from beach areas at distances of 10-100 yards from the source. The highest HF concentration, 0.99 ppm, was measured in a dense LAZE plume approximately 12 yards from the source. Fluoride anion was also detected at quantifiable levels in four samples collected from other sampling locations separate from the beach and outside of the LAZE plume. The presence of fluoride anion in these background, ambient samples may possibly be attributed to vent gas emissions from Kilauea. None of the area HF concentrations exceeded the personal occupational exposure standards/criteria of OSHA and ACGIH (3 ppm as a TWA) or NIOSH (3 ppm as a TWA and 6 ppm as a STEL), although HF exposures would have an additive health effect in combination with HCl exposures (10)…


The interaction of lava and sea water generated quantifiable concentrations of HCl and HF; HCI was predominant. Condensate samples of LAZE were highly acidic, with a pH of 1.3. The potential for exposure to inorganic acids (HCl and HF) presents the most significant health risk from LAZE. HCI and HF concentrations were highest in dense plumes of LAZE within approximately 12 yards of the sea. The HCl concentrations measured at those
sampling locations exceeded the 5 ppm ceiling standard and presented an occupational health hazard according to occupational exposure criteria of OSHA, ACGIH, and NIOSH (8-11). HF concentrations were below existing occupational exposure standards, although HF would produce additive exposure effects in combination
with HCI (9,15,16). HCI and HF concentrations decreased with distance from the source. At distances of approximately 400 yards or greater, HCl concentrations, measured directly in the diluted plume, were
less than 1 ppm…