A. Hulster et al., SOIL-PLANT TRANSFER OF POLYCHLORINATED DIBENZO-P-DIOXINS AND DIBENZOFURANS TO VEGETABLES OF THE CUCUMBER FAMILY (CUCURBITACEAE), Environmental science & technology, 28(6), 1994, pp. 1110-1115
In a preliminary study in fruits of zucchini (Cucurbita pepo L. convar
. giromontiina) polychlorinated dibenzopdioxins and dibenzofurans (PCD
D/PCDF) concentrations were found which were approximately 2 orders of
magnitude higher than in other fruits and vegetables examined. These
results formed the basis for field experiments on the uptake of PCDD/P
CDF from contaminated soils by zucchini and related plant species (pum
pkin and cucumber). The experimental design allowed the discrimination
of several uptake pathways and an evaluation of their contribution to
the total PCDD/PCDF contamination of the plants. Using two soils with
different organic matter content, additional information was obtained
on the influence of soil parameters on the soil-plant transfer of PCD
D/PCDF. For zucchini and pumpkin (both belonging to the genus Cucurbit
a), root uptake of PCDD/PCDF and subsequent translocation to the shoot
s and into the fruits is the main contamination pathway. Cucumber plan
ts (Cucumis sativus L.), by contrast, are mainly contaminated by depos
ition of airborne PCDD/PCDF and, consequently, show much lower PCDD/PC
DF concentrations. The nature of the mechanism responsible for the une
xpectedly high soil-plant transfer into plants of the species Cucurbit
a pepo L. remains to be clarified.