APPLICATION OF TOTAL-REFLECTION X-RAY-FLUORESCENCE SPECTROMETRY TO THE ANALYSIS OF AIRBORNE PARTICULATE MATTER

Two fast and simple methods for the collection and characterization of airborne particulate matter were developed. Airborne dust was collect ed by filtration and by impaction with a six-stage Berner impactor. Fo r both methods cellulose nitrate filters were used as collection media . The exposed parts of the filters were punched out and digested with a cool-plasma asher (CPA). After dissolving the residue with nitric ac id and addition of an internal standard element, the analysis was carr ied out by total-reflection X-ray fluorescence spectrometry (TXRF). Th e collection time could be reduced to less than 1 h and trace elements be determined in the range of ng m(-3). The detection, however, was l imited by blank values caused by the sampling devices, especially by t he impactor made of stainless steel. High blank values of chromium, ma nganese, iron and nickel as typical constituents of stainless steel we re found. To avoid these high blanks, a more suitable material was cho sen for the construction of an impactor of the same type. Hereby the b lank values could be reduced to below the detection limits of about 10 0 pg m(-3). (C) 1997 Elsevier Science B.V.