Bioaccessibility of potentially harmful soil elements

Quantitative guidelines for assessing risks
from potentially harmful elements in soil are
associated with several scientific problems.
There are difficulties in establishing concentrations
of contaminants beyond which risks from exposure
to these contaminants would be unacceptable. This
requires not only scientific (toxicological) information
on the health effects, but also an element of judgement
on what is unacceptable risk. In addition, soil is only
one of the sources of contaminant exposure, and its
effect, and the cost of dealing with it, needs to be kept
in proportion with the total exposure to contaminants
from all sources.