title: Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.
abstract: A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.
authors.affiliation: Dpto. Química Analítica, Nutrición y Bromatología. Instituto de Investigación y Análisis Alimentario, Universidad de Santiago de Compostela, 15782, Santiago de Compostela, Spain.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Pena
authors.forename: Luis
authors.initials: L
authors.lastname: Pensado
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Casais
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Mejuto
authors.forename: Rafael
authors.initials: R
authors.lastname: Cela
mesh_terms: D002845:Chromatography / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D006586:Hexanes / Q000737:chemistry; D006868:Hydrolysis; D006878:Hydroxides / Q000737:chemistry; D008872:Microwaves; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D017680:Potassium Compounds / Q000737:chemistry; D015203:Reproducibility of Results; D012503:Saponins / Q000737:chemistry*; D012722:Sewage; D052616:Solid Phase Extraction; D012997:Solvents; D013050:Spectrometry, Fluorescence / Q000379:methods
chemical_list: D006586:Hexanes; D006878:Hydroxides; D011084:Polycyclic Aromatic Hydrocarbons; D017680:Potassium Compounds; D012503:Saponins; D012722:Sewage; D012997:Solvents; C026385:n-hexane; C029943:potassium hydroxide