Bioavailability and effects of malathion in artificial sediments on Simocephalus vetulus (Cladocera: Daphniidae).

The pollution of aquatic sediments is critical to the health of aquatic ecosystems. Sediment dwelling organisms are key links in food webs that can lead toxic materials to higher level consumers, such as fish and humans. Sediments in aquatic systems can be both sink and source for inorganic and organic contaminants. The assessment of sediment contamination by laboratory bioassays is essential since it measures the toxicity and the biological response associated with specific concentrations of chemical pollutants. Furthermore, these can indicate if degradation or binding could reduce the bioavailability of chemicals, and can also set the basis for the establishment of safe concentrations.