METROLOGICAL CHARACTERISTICS AND COMPARISON
OF ANALYTICAL METHODS FOR DETERMINATION OF CHROMIUM TRACES IN WATER SAMPLES
Andrzej Bobrowski,a*
Jan Mocak,b Janusz
Dominik,c Helena Pereira,c
Bogusław Baś,a
and Wiesław Knapd
a Department
of Technology of Building Materials, Faculty of Materials Science and
Ceramics, AGH University of Science and Technology, Al. Mickiewicza
30, 30-059 Krakow, Poland
b Department of Analytical
Chemistry, Slovak
c Institut
F.-A. Forel, Université de Genève, CH-1290 Versoix,
dFaculty of Geology, Geophysics and Environmental Protection, AGH University of Science and Technology, Al. Mickiewicza 30, 30-059 Krakow,
* Corresponding author: E-mail: gcbobrow@cyf-kr.edu.pl; fax: +48 12
617 24 52
Abstract
The analytical
performance of the inductively coupled plasma mass spectrometry, absorption spectrophotometry and catalytic adsorptive stripping voltammetry has been compared for trace chromium
determination in water samples. The following metrological
characteristics were calculated: trueness, precision, linear analytical range, detection and
quantification limits. The limit of detection,
and the limit of quantification were calculated by the ULA method, which takes
into consideration the uncertainties of the slope and the intercept of the calibration
plot, designed especially for this purpose, as well as by traditional way as
the 3- and 10-fold multiply of the blank standard deviation.
The
possibility of the speciation study of both chromium oxidation states, Cr(VI) and Cr(III), has also been considered. The ICP MS procedures were applied to the
determination of total chromium in river water samples. The catalytic
adsorptive stripping voltammetric method with DTPA
and nitrate is sufficiently sensitive for the determination of chromium traces
at the level of 0.01 to 0.1 mg/L and suitable for the chromium speciation studies.
Key words: chromium,
speciation, ICP MS, catalytic adsorptive stripping voltametry,
adsorption spectrophotometry