Comparison of predicted heavy metal concentrations with (eco)toxicological soil quality standards
Vergelijking van voorspelde metaalgehalten in landbodems met (eco)toxicologische risiconiveaus
26 May 2012, PDF |
46 pages |
van Dijk S, Kramer PRG, Franken ROG, Posthuma L
RIVM Report 733007005
Regional waters are dredged once every 5 to 20 years to maintain the water discharge. This study has contributed to the determination of the quality objectives to be met by the dredged material if it is disposed of in the adjacent soil. In a preceding study the present and future sediment quality with respect to the concentration of PAH (polycyclic aromatic hydrocarbons) and heavy metals were investigated. The accumulation of cadmium, copper, lead and zinc in the adjacent soil is modelled by repeatedly distributing contaminated sediments into different categories of land use and soil type. Here, the predicted heavy-metal soil concentrations from the above-mentioned study are used to calculate the probability of exceeding different (eco)toxicological standards. This implies a first rough estimation of (eco)toxicological risks caused by the distribution of contaminated sediment. The goals and accuracy of the different (eco)toxicological standards differ substantially. Some of the standards for copper and zinc have already been exceeded without the distribution of contaminated sediment. For most of the metals the majority of the (eco)toxicological standards are exceeded by the distribution of sediment having a so- called pollution level of 'class 2'. Further investigation is recommended to discover the (eco)toxicological meaning of exceeding the toxicological standards.