The Suitability of the Lepidium Test for Assessing the Toxicity of Leachate from a Municipal Landfill

Sealing of landfill and treatment of leachate is a very important issue in the operation of the landfill, part of which is monitoring of leachate. In addition to the assessment of quantitative and qualitative characteristics, monitoring of leachate should also involve the assessment of leachate phytotoxicity. This is particularly important in the case of migration of leachate and its impact on the soil and water environment. The aim of this study was to determine phytotoxicity of leachate from a municipal landfill based on the plant stress test (the Lepidium test). The Lepidium test was considered as useful in the assessment of toxicity of landfill leachate, resulting from changes in the plant growth depending on leachate concentration in the solution. The use of the Lepidium test allowed for the determination of an approximate threshold volume of leachate which leads to the inhibition of test plant growth. Undisturbed plant development was achieved in the environment with leachate concentrations below 1÷2%. It is also suggested that the test methodology should be extended in order to measure protein concentration. The usefulness of measuring peroxidase was not demonstrated. Based on the values of physico-chemical indicators of leachate and the content of metals, no significant toxic factors were found to inhibit the growth of the test plant.