In landfill leachates the persistent organic pollutants and heavy
metals are often associated with particulate matter. In addition,it is well known that some industrial wastes and effluents are genotoxic,and their genotoxicity is predominantly associated with particulate matter. Thus,the discharge of landfill leachate in a wetland system may result in the incorporation of many toxicants,including genotoxic compounds into the bottom sediments causing a subsequent hazard for the benthic organisms. They may also eventually become reintroduced in to the water column through resuspension or trophic transfer.