TOXICITY ASSESSMENT OF LANDFILL LEACHATES WITH A BATTERY OF BIOASSAYS

In this study, the toxicity of the leachate from the municipal landfill was evaluated and assigned to its chemical composition. Leachate samples were collected considering different seasons and assessed for their toxicity by using Thamnotox with Thamnocephalus platyurus, Daphtox with Daphnia magna, Vibrio fischeri, Lemna minor, and Lepidium sativum. Leachate samples were also characterized measuring their physical and chemical parameters. Relationships between the chemical composition and the toxicity of leachate samples were established. EC50, values for Thamnotox, Lemna minor, and Lepidium sativum were negatively correlated with the COD content. There were significant correlations between the TOC with EC50 values of Vibrio fischeri and Lemna minor tests. Vibrio fischeri wasthe most sensitive test organism investigated for the landfill leachate. Considering toxic unit values, leachate samples were highly to very highly acute toxic, according to all the tests carried out.