DETERMINATION OF ARSENIC AND SELENIUM BY INJECTION COMBINED WITH COLD-TRAP COLLECTION OF HYDRIDE AND CONTINUOUS-FLOW HYDRIDE-ATOMIC ADSORPTION TECHNIQUE

A cold-trap hydride collection - injection and a continuous-how hydrid e - AAS systems were developed for the high-sensitivity determination (detection limit 10-20 pg/ml) of arsenic and selenium. The accuracy an d reproducibility of the method were controlled by means of solutions prepared after fusion of international standard samples. The results o f determination showed good agreement with the internationally accepte d standardized values. The reproducibility of the results was good, es pecially in view of the extremely low concentration involved. The meth od was successfully applied to the determination of very low levels of arsenic and selenium in food and water samples.