Yttrium normalisation:: A new tool for detection of chromium contamination in soil samples

The measurement of chromium and yttrium concentration could give a chance to detect 5-10 times less chromium contamination in soil by using the yttrium normalisation method. The principle of the method is the following: elements such as chromium and yttrium exist naturally in the soil in a strongly bonded form. Therefore, in a noncontaminated area there should be a close correlation between the yttrium and chromium concentrations. If the measured Cr concentration in a sample is not on the Cr-Y trend line then the distance of plotted point from the line indicates the amount of anthropogenic chromium. Anthropogenic chromium can be detected only in the case when the contamination does not contain yttrium. This theory was tested in an agricultural-toxicological field experiment where Cr(VI) was added to the soil. Applying the yttrium normalisation method a much smaller anthropogenic effect was detected than by other evaluation methods.