Adequate sampling, an important step towards reiable decisions based on analytical results

The efforts spent on judgments of how to perform sampling are often small compared to other

steps in the analytical procedure. As a result decisions may be based on irrelevant results. If

the sampling is intended to provide information how to reduce and control environmental

pollution, it is important to design the sampling strategy according to scientific principles.

Sampling will be discussed in relation to determinations of organic as well as inorganic

species in different types of polluted matrices, .e.g. water, sediments and air. Examples will

be taken from our own research projects about treatment processes for contaminated

matrices.. Accurate sampling involves a basic planning including objectives, cost

effectiveness versus the budget, variability of contamination leading to statistical

considerations, site accessibility and robustness of the used devices. A strategy for the

sampling, often in a form of a scheme, is needed. The Laqua Protocol developed within our

research projects will be presented. This protocol is flexible and dynamic and can be altered

and optimized based on the demands at the individual sampling site. Sampling of complicated

matrices often creates problems with interfering agents and breakdown of unstable analytes.

In this type of samples the concentrations of analytes are generally several orders of

magnitudes lower than the concentrations of major constituents in the sample. Accordingly

the advantages of an early work-up, preferably in connection with a sampling procedure, is

paid especially attention