Total arsenic concentration analytical determination

II. ANALYTICAL METHODS FOR THE DETERMINATION OF TOTAL ARSENIC CONCENTRATIONS... 

Nowadays, most of the arsenic-orientated analytical work is dealing with the determination of total arsenic concentrations in biological samples. The methods developed for this purpose allow the determination of trace and ultratrace concentrations simultaneously with other elements. The huge differences in the acute toxicities make it evident that total arsenic concentrations are not sufficient for risk assessment. Nowadays, methods for the determination of arsenic compounds are becoming more robust and are (or will be soon) routine methods. Scientists who investigate toxic and beneficial effects of arsenic must concentrate on the determination of arsenic compounds. 

Cl Amarasiriwardena, N Lupoli, V Potula, S Korrick, H Hu. Determination of total arsenic concentrations in human urine by inductively coupled plasma mass spectrometry A comparison of the accuracy of three analytical methods. Analyst 123 441-445, 1998. 

Finally, we wish to point out the limitations of the following data set. Analytical techniques for determining organoarsenic species have improved steadily since the first of such methods was reported in the 1970s. Nevertheless, most of the methods used today involve separations (or derivatizations) in aqueous media. Consequently, these methods are only capable of determining water-soluble arsenicals, and arsenic compounds that are not soluble in water remain unidentified. The presence of such compounds has often been ascertained by the difference between concentrations of total arsenic and water-soluble arsenic. Future work should profit from techniques capable of determining water-insoluble arsenic species. 

The aim of this work was to investigate the arsenic mobilization from the tailings material (200 - 500 pg/g As) into the seepage water (up to 3.5 mg/L As) and the process of seepage water effluent forming an immobilized precipitate (up to 8 % As) in the creek. Different analytical methods for the determination of total concentrations and different sequential extraction methods as well as hyphenated techniques for speciation analysis were applied to follow the way of the arsenic in this environment. 

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