Uptake of Organic Contaminants from Soil into Vegetables and Fruits - Dealing with Contaminated Sites: From Theory Towards Practical Application - page 403

A free guide to vegetation sampling for screening of subsurface pollution is
available from the web (Trapp et al. 2009 ).
9.10 Conclusions
What can be concluded from this review? An important conclusion is that the polar
contaminants are preferably translocated from soil and accumulate in leaves and
fruits. Lipophilic contaminants will be retained in soil, roots and the lower stem
and will not reach the leaves or fruits in significant amounts. Thus, polar and non-
volatile contaminants, i.e. contaminants with low K OW and K AW , have the highest
accumulation potential from soil into plants. This is in conflict with the usual con-
cept of bioaccumulation, where high bioaccumulation is assumed to occur for highly
lipophilic contaminants (EC 2003 ; Mackay and Fraser 2000 ). Furthermore, under
background conditions, all contaminants except the polar and non-volatile contam-
inants will preferably be taken up from air and the concentration in soil does not
have much impact on the concentration in leaves, unless it is far above chemical
equilibrium.
The number of available experimental data on plant uptake of contaminants
increases. Often, model concepts and measurements are in good agreement, but
we may also encounter surprises. Plants are living organisms, and the uptake pro-
cesses are complex and variable. Uncertainties in the model predictions are high,
and large variations may be expected in predicted, but also in experimental data,
due to the variations of contaminant-specific, plant physiological and environmental
parameters as described in this chapter.
Acknowledgement We thank our editor, Frank Swartjes, for his initiative, patience and help. Our
work is supported by the European Union 6th Framework Program of Research, Thematic Priority
6 (Global change and ecosystems), contract number GOCE-CT-2007-036976, project 2-FUN, and
contract number GOCE 037017, project OSIRIS. This work received also financial support from
the Danish Council for Strategic Research, project REMTEC, contract 2104-07-0009. Support for
this work was furthermore provided through a PhD grant of the University of Copenhagen for
Charlotte N. Legind.
Model Availability Most models mentioned in this chapter are freely available via the authors.
Please send an email if you are interested.
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