Ecotoxicological assessment and evaluation of a pine bark biosorbent treatment of five landfill leachates

• Published in: Waste management (Elmsford) 2012-10, Vol.32 (10), p.1886-1894
• Main Authors: Ribé, Veronica, Nehrenheim, Emma, Odlare, Monica, Gustavsson, Lillemor, Berglind, Rune, Forsberg, Åke
• Format: Article
• Language: English
• Subjects: Adsorption; Animals; Applied sciences; Biological and physicochemical phenomena; Chlorophyta; Daphnia; Ecotoxicological test battery; Ecotoxicology; Exact sciences and technology; Filter treatment; Filtration; General treatment and storage processes; Hydrogen-Ion Concentration; Landfill leachate; Metals, Heavy - isolation & purification; Natural water pollution; Other wastes and particular components of wastes; Phenols - isolation & purification; Pine bark; Pinus - chemistry; Plant Bark - chemistry; Pollution; Principal Component Analysis; Salmonella typhimurium; Toxicity Tests; Waste Disposal, Fluid; Wastes; Water Pollutants, Chemical - isolation & purification; Water Pollutants, Chemical - toxicity; Water treatment and pollution
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2012.05.011

► The filter material pine bark was evaluated as a treatment for five landfill leachates. ► The change of toxicity after treatment was studied using a battery of aquatic bioassays. ► The results were analyzed in a Principal Component Analysis and evaluated in a toxicity classification. ► Filter treatment removes metals effectively but does not generally alter leachate toxicity. ► The study highlights the importance of evaluating treatment efficiency from the perspective of potential recipient effects. When selecting a landfill leachate treatment method the contaminant composition of the leachate should be considered in order to obtain the most cost-effective treatment option. In this study the filter material pine bark was evaluated as a treatment for five landfill leachates originating from different cells of the same landfill in Sweden. The objective of the study was to determine the uptake, or release, of metals and dissolved organic carbon (DOC) during a leaching test using the pine bark filter material with the five different landfill leachates. Furthermore the change of toxicity after treatment was studied using a battery of aquatic bioassays assessing luminescent bacteria (Vibrio fischeri) acute toxicity (30-min Microtox®), immobility of the crustacean Daphnia magna, growth inhibition of the algae Pseudokirchneriella subcapitata and the aquatic plant Lemna minor; and genotoxicity with the bacterial Umu-C assay. The results from the toxicity tests and the chemical analysis were analyzed in a Principal Component Analysis and the toxicity of the samples before and after treatment was evaluated in a toxicity classification. The pine bark filter material reduced the concentrations of metal contaminants from the landfill leachates in the study, with some exceptions for Cu and Cd. The Zn uptake of the filter was high for heavily contaminated leachates (≥73%), although some desorption of zinc occurred in less contaminated waters. Some of the leachates may require further treatment due to discharge into a natural recipient in order to reduce the risk of possible biological effects. The difference in pH changes between the different leachates was probably due to variations in buffering capacity, affected by physicochemical properties of the leachate. The greatest desorption of phenol during filtration occurred in leachates with high conductivity or elevated levels of metals or salts. Generally, the toxicity classification of the leachates implies that althoug