Trace determination of strontium and barium in river waters by inductively coupled plasma-atomic emission spectrometry using an ultrasonic nebulizer

Inductively coupled plasma-atomic emission spectrometry in conjunction with an ultrasonic nebulizer was employed for the determination of Sr and Ba in river waters at parts per billion (mug l(-1)) levels without pre-concentration. The ultrasonic nebulizer, equipped with a desolvation system, enhanced the analytical sensitivity by ten to twenty fold compared to conventional pneumatic nebulizers. The detection limits for Sr and Ba, ascertained from blanks and reference samples made in 0.05% NaCl solution, were 0.045 mug l(-1) and 0.16 mug l(-1) respectively. The accuracy of measurements, based on analyses of solutions of reference materials (G-2 and W-1) and multi-element commercial standards (Merck(R)), was +/- 10%. Replicate analyses of samples and reference samples showed measurement precision to be to be better than +/- 5%, which is adequate considering that the concentration of Sr and Ba in river waters varies by one to two orders of magnitude.