ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 2, pp. 279!283. + Pleiades Publishing, Inc., 2006.
Original Russian Text + Yu. E. Dolgova, V. A. Kudryavtseva, 2006, published in Zhurnal Prikladnoi Khimii, 2006, Vol. 79, No. 2, pp. 279!283.
OF CHEMISTRY AND TECHNOLOGY
Application of New Types of Fibrous Sorbents for Sampling
of Dissolved Species of Heavy Metals in Natural Waters
Yu. E. Dolgova and V. A. Kudryavtseva
St. Petersburg Scientific Research Center for Ecological Safety, Russian Academy of Sciences, St. Petersburg, Russia
Received December 2, 2005
Abstract-The article discusses the importance and specific features of the preparatory stages in ecoanalytical
monitoring of natural water, aimed to determine the content of heavy metals. A procedure was developed for
sampling of dissolved species of heavy metals with sorbents. The influence of humic substances on the sorp-
tion of heavy metals was elucidated. The results obtained with the technique suggested are reported.
Analytical monitoring of pollution of natural wa-
ter is an urgent problem faced by modern hydroecol-
ogy and environmental analytics. In particular, of spe-
cial importance is monitoring of the content of heavy
metals (HMs)  ranking among the most hazardous
biologically components of natural water.
The general scheme of ecoanalytical monitoring of
any natural object includes the following successive
stages: sampling, preservation and transportation of
samples, sample preparation, instrumental analysis,
and processing and interpretation of the results .
Sampling is very important in environmental mon-
itoring; it primarily determines the accuracy of the sub-
sequent analysis. Above all, it is necessary to ensure
conditions under which the sample is representative.
Of much importance are the specific features of the ob-
ject and the goal of investigation. There is a need
in several replicate measurements, which increases
the minimal volume of the sample. Even in the sampl-
ing stage, it is necessary to take special measures to
avoid contamination. Such measures are typically
described in detail either in appropriate techniques or
in special manuals of analysis. Careless handling and
inappropriate storage may be responsible for changes
in the composition of the samples via photolytic or
thermal decomposition, chemical reactions, or micro-
In many cases, practicians have to preserve the
samples, so as to carry out the analysis at a later time
, rather than under field conditions; this can in-
crease the inaccuracy of the subsequent analysis.
Sample preparation is the first stage of the analyt-
ical procedure proper. It is aimed to convert the com-
ponent being analyzed to a form suitable for analysis
by the chosen method, to remove or mask interfering
substances, and, in some cases, to precisely adjust
the concentration to make the expected content of
the component being analyzed close to the middle of
the operating range of the analytical method used .
Analysis of dissolved species of metals typically
requires taking no less than a 1-l isokinetic water sam-
ple (or several liters of separate samples taken across
the entire river section). The water samples taken
should be conserved at the sampling site, and analysis
should be carried out within a brief period (not later
than in 537 days). The use of various conserving
agents after sampling of natural water has been re-
ported. To preserve dissolved species of heavy metals,
the samples are acidified with nitric acid to pH < 2 or
cooled to 334oC and stored at this temperature ,
which is technically troublesome. However, sample
preservation does not afford a constant composition
of a water sample for an infinite period . Bringing
samples to stationary analytical laboratories frequently
takes a relatively long time, up to several weeks. This
inevitably entails loss of dissolved species of heavy
metals, e.g., via biochemical processes and sorption
on the dishware, which distorts analytical data.
Analytical practice widely uses sorption preconcen-
tration, in particular, in preparation of natural water
samples for analysis. The sorption preconcentration
has advantages of simplicity and easy performance,
high efficiency, rapidity, and possibility of combina-