Tg. Hinton et al., FOLIAR ABSORPTION OF RESUSPENDED CS-137 RELATIVE TO OTHER PATHWAYS OFPLANT CONTAMINATION, Journal of environmental radioactivity, 30(1), 1996, pp. 15-30
The foliar absorption of Cs-137 sorbed to suspended soil particles was
quantified at two Ukranian locations contaminated by different forms
of Chernobyl fallout. Our experimental design, allowed us to separate
the pathways of foliar absorption, root uptake, and contamination adhe
ring to plant surfaces. Foliar absorption, root uptake, and the quanti
ty of soil-attached Cs-137 adhering to leaves were greater at a loamy
sand site contaminated with condensation-type fallout (Polesskoye), th
an at a sandy site contaminated with fuel-particles (Chistogolavka) (0
.7 vs 0.04 kBq kg(-1); 20.8 vs 0.9 kBq kg(-1); and 3.2 vs 1.1 mBq cm(-
2), respectively). We found that when Cs-137 was very mobile in soils,
root uptake grossly dominated all other plant contamination pathways.
As the plant/soil concentration ratio decreased, a relative increase
in foliar absorption from resuspension occurred, but it was quickly su
rpassed in importance by soil adhering to plant surfaces. The data sug
gest that although foliar absorption of Cs-137 from suspended soil is
measurable, it is inconsequential relative to other plant contaminatio
n pathways, and does not need to be considered as a critical pathway i
n routine radionuclide transport models.