title: Determination of organochlorine compounds in neuston from the Mediterranean.
abstract: A reliable analytical procedure was developed to determine trace levels of organochlorine compounds in neuston samples. Freeze-dried samples were extracted by sonication (3 x 15 ml cyclohexane, 15 min) followed by gel permeation chromatography (GPC) and gas chromatography electron capture detection (GC-ECD) determination. Neuston samples may present great differences in their lipid content, which may become a drawback for the analytical determination of hydrophobic pollutants. In this way, GPC fractionation combined with Florisil cleanup was successfully used to avoid potential lipidic interferences in the GC-ECD determination. Organochlorine compounds were determined by GC-ECD and a standard addition method was performed to evaluate the recoveries of 41 PCB individual congeners (80 +/- 20%). The congeners with lower K(ow) (octanal water partition coeeficient) values showed lower recoveries (54 +/- 7%) than the more lipophylic ones (80 +/- 7%). The limits of detection ranged from 0.001 to 0.211 ng g(-1) of wet samples. The reproducibility of the developed analytical methodology for independent replicates (n = 3) at low pg g(-1) levels was quite satisfactory (RSD 18 +/- 10%).
authors.affiliation: Environmental Chemistry Department, IIQAB-CSIC, C/Jordi Girona, Barcelona, Spain.
authors.forename: N
authors.initials: N
authors.lastname: García-Flor
authors.forename: R
authors.initials: R
authors.lastname: Alzaga
authors.forename: L
authors.initials: L
authors.lastname: Ortiz
authors.forename: J M
authors.initials: JM
authors.lastname: Bayona
authors.forename: J
authors.initials: J
authors.lastname: Albaigés
mesh_terms: D000818:Animals; D002849:Chromatography, Gas / Q000379:methods; D002850:Chromatography, Gel / Q000379:methods; D004583:Electrons; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D005612:Freeze Drying; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D007448:Invertebrates / Q000378:metabolism*; D017633:Magnesium Silicates; D010573:Pesticide Residues / Q000032:analysis*; D011078:Polychlorinated Biphenyls / Q000032:analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004785:Environmental Pollutants; D006843:Hydrocarbons, Chlorinated; D017633:Magnesium Silicates; D010573:Pesticide Residues; C005013:Florisil; D011078:Polychlorinated Biphenyls