The digested samples were further divided into two set , one set of digested solution was subjected to ETAAS for total As determination, while other set was subjected to cloud point extraction of As ,prior to subjecting ETAAS.
The proposed CPE method for the preconcentration of As as a prior step to its determination by ETAAS, is a simple, rapid, sensitive, inexpensive and non-polluting preconcentration technique.
For direct determination of As and Cd in the Baltic seawater sample by ETAAS using a colloidal palladium modifier the seaweed samples were diluted with Milli-Q water (1 : 5) and the same processing program (Tables 1 and 2) was used as for the analysis of seaweeds.
In this work, the determination of As and Cd in the Baltic seawater sample by ETAAS using a colloidal palladium modifier was carried out.
analysis protocol was applied to the EBC samples, and the results were confirmed by inductively coupled plasma--mass spectrometry (ICP-MS) in a separate laboratory, with an interlaboratory regression coefficient of 0.
The method is a further refinement of existing ETAAS methods in our laboratory (28, 29), adapted to the transverse-heated graphite atomizer furnace and focused on the determinations of low (<150 [micro]g/L) lead concentrations similar to those observed at present in samples from the general population.
The example of the assay of lead in blood by ETAAS was well suited for this purpose because the properties and the state of the art of the technique are well documented, because both CRMs and pure standards are available, and because several well-established EQAS are active.
The calibration solutions used for ETAAS
determination were prepared by diluting Cr(III) and Cr(VI) stock solutions with diluted HN[O.
9] Nonstandard abbreviations: BPb, blood lead; PT, proficiency testing; CLIA 'SS, Clinical Laboratory Improvement Amendments of 1988; NYSDH, New York State Department of Health; WSLH, Wisconsin State Laboratory of Hygiene; ASV, anodic stripping voltammetry; RMSE, root mean squared error; and ETAAS
, electrothermal atomization atomic absorption spectrometry.
The accuracy and precision of the ETAAS
method have been described elsewhere (16).
Total aluminum and iron concentrations in serum samples and the ultrafiltrates were determined by ETAAS
, using operating conditions similar to those described previously (19-21).
In view of its potential analytical performance, ETAAS
is at present the method of choice to determine Sr in biological samples.