Synchrotron radiation total reflection for rainwater analysis

Total reflection X-ray fluorescence analysis excited with synchrotron radia tion (SR-TXRF) has been used for rainwater trace element analysis. The samp les were collected from four different sites at Campinas City, SP, Brazil. Standard solutions with gallium as internal standard were prepared for the calibration system. Rainwater samples of 10 mu l were added to Perspex refl ector disks, dried under vacuum and analyzed for 100 s measuring time. The detection limits obtained for K-shell lines varied from 29 ng ml(-1) for su lfur to 1.3 ng ml(-1) for zinc and copper, while for L-shell the values wer e 4.5 ng ml(-1) for mercury and 7.0 ng ml(-1) for lead. (C) 2000 Elsevier S cience B.V. All rights reserved.