| Popis: |
A comprehensive review is made of sources, occurrence, removal, health effects and water quality standard of barium in public drinking water supplies. The primary source of naturally occurring barium in drinking water results from the leaching and eroding of this metal from sedimentary rocks into the aquifers of ground water. It is a localized problem in several areas of the United States. The removal of barium from drinking water appears to be most efficiently accomplished utilizing ion exchange softening. Health effects studies are based primarily on animal experimentation. Such effects include stimulation of smooth, striated, and cardiac muscle, elevation of blood pressure, initiation of catecholamine release, rapid and preferential deposition in bone, and excretion principally in the feces. Humans over 60 years of age appear to be at high risk to developing cardiac arrhythmias following the barium enema. The current United States drinking water standard of 1.0 mg/l is based on several faulty assumptions and should be critically reevaluated. |
