title: Optimization of an effective extraction procedure for the analysis of microcystins in soils and lake sediments.
abstract: Microcystin analysis in sediments and soils is considered very difficult due to low recovery for extraction. This is the primary limiting factor for understanding the fate of toxins in the interface between water and sediment in both the aquatic ecosystem as well as in soils. In the present study, a wide range of extraction solvents were evaluated over a wide range of pH, extraction approaches and equilibration time to optimize an effective extraction procedure for the analysis of microcystins in soils and lake sediments. The number of extractions required and acids in extraction solutions were also studied. In this procedure, EDTA-sodium pyrophosphate solution was selected as an extraction solvent based on the adsorption mechanism study. The optimized procedure proved to be highly efficient and achieved over 90% recovery. Finally, the developed procedure was applied to field soil and sediment sample collected from Chinese lakes during bloom seasons and microcystins were determined in six of ten samples.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, The Chinese Academy of Sciences, Wuhan 430072, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.forename: Nanqin
authors.initials: N
authors.lastname: Gan
authors.forename: Lirong
authors.initials: L
authors.lastname: Song
mesh_terms: D001427:Bacterial Toxins / Q000032:analysis*; D002623:Chemistry Techniques, Analytical; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D005618:Fresh Water / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D052998:Microcystins / Q000032:analysis*
chemical_list: D001427:Bacterial Toxins; D004785:Environmental Pollutants; D052998:Microcystins