Soil contamination in landfills: a case study of a landfill in Czech Republic

Abstract

A phytotoxicity test was determined to assess ecotoxicity of landfill soil. Sinapis alba L. was used as a bioindicator of heavy metals. Soil samples 1–8, which were taken from the landfill body, edge of the landfill body, and its vicinity meet the limits for heavy metals Co, Cd, Pb, and Zn specified in the applicable legislation. Hg and Mn threshold values are not established in legislation, but values have been determined for the needs of the landfill operator. For heavy metals Cr, Cu, and Ni sample 2 exceeded the threshold values, which attained the highest values of all the samples tested for Cr, Cu, and Ni. For Cr and Ni the values were several times higher than values of the other samples. The second highest values for Cr, Cu, and Ni showed sample 6 and 7. Both samples exceeded the set limits. An increase in plant biomass was observed in plants growing on plates with soil samples, but no changes in appearance, slow growth, or necrotic lesions appeared. Ecotoxicity tests show that tested soils (concentration of 50 %) collected from the landfill body, edge of the landfill body, and its vicinity reach high percentage values of germination capacity of seeds of Sinapis alba L. (101–137 %). At a concentration of 25 %, tested soil samples exhibit lower values of germination capacity – in particular samples 3 to 8 – yet the seed germination capacity in all eight samples of tested soils ranges between 86 and 137 %.