Soil Intervention Values are generic soil quality
standards based on potential risks to humans and eco-systems. These values
are used to determine whether or not contaminated soils meet the criteria
for "serious soil contamination" as stated in the Dutch Soil Protection Act.
With reference to potential risks to humans, Maximum Permissible Risk (MPR)
values, quantifying the human-toxicological risk limits for some 50
chemicals and chemical classes, were derived in the 1991-1993 period. These
MPRs, which have since been updated, comprise limits on tolerable daily
intake, tolerable concentration in air, and oral cancer risk and/or
inhalation cancer risk. In total, the compounds comprise 12 metals
(including cadmium, lead and mer-cury), 10 aromatic compounds (including the
polycyclic aromatics), 13 chlorinated hydrocarbons (including dioxins and
polychlorinated biphenyls), 6 pesticides (including DDT and the drins) and 7
other compounds (including cyanides and total petroleum hydrocarbons). A
toxicity profile has been compiled for each compound or compound class. It
consists of a concise summary of the available toxicity data, information on
back-ground exposure and a survey of existing limit values derived by other
organisations. An updated MPR for each compound (or class of compounds) in
question is deduced from the respective profile.
