Aqua regia extraction represents the amount of elements
that can be potentially labile in the environment better than
those obtained after the HF digestion. That was clearly confirmed
with the elevated levels of Cu, Pb, Zn and P in most
of the analyzed samples extracted by aqua regia, manly connected
with anthropogenic contamination. Although it is
noticeable that Ni content determined after total digestion
are higher that corresponding pseudo-content, significantly
greater concentrations for aqua regia extraction were determined
in VV production area (Tables 4 and 5).