Isotope Method for Source Analysis of Metals in Soil

Figure: Range of the measured substance fluxes for uranium (U) at three arable crop sites (2014-2015).

At five NABO sites, including two arable crop sites and three grassland sites, and one site in the canton of Baselland, all relevant inputs and emissions of cadmium, copper, zinc and uranium were measured for two years in the field.

Metals that accumulate in the soil can have long-term qualitative and quantitative effects on the produced food. To counteract this problem, the most important metal sources need to be analysed and identified. The analysis focuses on the three trace metals cadmium, copper and zinc, which accumulate significantly in agricultural soils of certain regions.

Like most chemical elements, trace metals consist of multiple stabile isotopes. The isotope ratio can be used to identify and quantify the various sources of metals in the soil. This method further helps to find out how metals move from the soil into the crops. An isotopic signature can be used to determine the sources of metals that are detected in soils and plant-based foods. These findings allow the development of measures for the reduction of metal contents.