Supercritical fluid extraction of water samples containing ultratrace amounts of organic micropollutants

A true solventless off-line supercritical fluid extraction (SFE) method has been developed, which does not use organic solvents for trapping and for w ashing out of analytes. Determination of polynuclear aromatic hydrocarbons, chlorinated pesticides, and polychlorinated biphenyls in aqueous solutions based on their direct SFE extraction and on off-line solventless SFE/gas c hromatography coupling has been done. This new method has a detection limit at the parts per billion/parts per trillion level. For the ultralow concen tration level of 0.1-1 ppt, direct SFE from water was more accurate, faster , and more reproducible than conventional sample preparation methods based on micro-liquid/liquid extraction and solid-phase extraction. (C) 1999 John Wiley & Sons, Inc.