CONSIDERATIONS IN AS ANALYSIS AND SPECIATION

Several problems with commonly used techniques that analyze for arseni c are reported, and solutions are proposed. Analytical techniques can accurately detect <0.5 mu g/L total arsenic if certain conditions are met: iron, nitrate, and other interferences are overcome in hydride ge neration techniques, poor recoveries are overcome in graphite furnace atomic adsorption techniques, and chloride interferences are accounted for in inductively coupled plasma mass spectrometry techniques. Becau se no techniques adequately preserve arsenic species during storage, a speciation protocol that is fast (about 5 min/sample), relatively ine xpensive (about $10/resin column), and user-friendly and that can be a pplied in the field was developed. Particulate arsenic represents a si gnificant fraction of total arsenic in drinking water.