Added Soil Quality Standard Approach

The added SQS approach assumes that only the anthropogenic added fraction of a natural element in the soil should be managed (Crommentuijn et al. 1997). The added quality standard is derived using ecotoxicity data obtained by subtracting the background values from the ecotoxicity value [EC(D)x] of the tested soils. 

When checking compliance, site-specific background values are subtracted from the monitoring data, and the latter are compared with the added quality standard. In theory, the use of the added quality standard approach avoids the potential problem 

FIGURE 5.9 Stepwise approach for deriving soil quality standards. 

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Correcting the quality standard for differences in bioavailability 5.10.1 Added Soil Quality Standard Approach... 

The robustness of a quality standard can be increased considerably by accounting for the bioavailability of the substance in an approach that is more accurate than use of added risk. The validation and implementation of international standards for such approaches is desirable. Bioavailable concentrations are influenced by the physical and chemical properties of a substance, soil characteristics, weather, and land use. Further efforts are necessary to gain understanding of the main regulating processes of availability and bioavailability to improve the prediction of risks for substances in soil and to derive more accurate SQS. 

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