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1.
Water Sci Technol ; 56(11): 151-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18057653

RESUMO

Different homologues of C4 to C8 perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFASs) were detected in German surface waters, bank filtrates, artificially recharged groundwaters, and drinking waters. If no point sources are located nearby, the typically measured levels are in the low ng/L range. In the presence of point sources, such as a fluorochemical production site, a leaching agricultural fertilizer contaminated with PFCAs and PFASs, or drained PFC containing fire-fighting foams, much higher concentrations in the microg/L range occur. This situation is similar in Germany and other countries.


Assuntos
Alcanossulfonatos/análise , Ácidos Carboxílicos/análise , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Água Doce , Alemanha , Abastecimento de Água
2.
J Chromatogr A ; 938(1-2): 199-210, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11771839

RESUMO

In this paper, analytical methods for the trace-level determination of 60 pharmaceuticals in aqueous samples are presented. The list of compounds amenable to the methods comprises analgesics, antiphlogistics, antirheumatics, beta-blockers, broncholytics, lipid-lowering agents (or their metabolites), antiepileptics, vasodilators, tranquillizers, antineoplastic drugs, iodinated X-ray contrast media, and antibiotics of different kind, mainly sulfonamides, macrolides, and penicillins. All methods are based on automated solid-phase extraction followed by GC-MS (after derivatization of the acid compounds) or HPLC-electrospray ionization MS-MS. After an intense validation, which included the determination of performance data according to the German standard method DIN 32645 (limit of detection, limit of identification, limit of determination), the determination of linearity, recovery, and repeatability and the study of matrix effects, the analytical methods were applied within a monitoring program on the occurrence of pharmaceuticals in groundwaters of Baden-Württemberg. During this monitoring program, it was found that several of the compounds under investigation could be detected in groundwaters and their occurrence could be traced back to an impact of municipal or industrial waste water.


Assuntos
Monitoramento Ambiental , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Indústria Farmacêutica , Cromatografia Gasosa-Espectrometria de Massas , Alemanha , Resíduos Industriais , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
3.
Anal Chem ; 72(21): 5466-72, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11080902

RESUMO

An ion-pair solid-phase extraction (IPE), ion-pair chromatography (IPC) procedure with fluorescence detection for the quantitative analysis of sulfonated naphthalene-formaldehyde condensates (SNFC) was developed, which provides full resolution of SNFC up to a degree of condensation n = 5 and partial resolution up to n = 15. Liquid chromatography-electrospray ionization-mass spectrometry confirmed that SNFC elute in the order of condensation. Response factors in fluorescence detection proved to be mass-constant, thereby allowing us to determine total SNFC amounts. With this IPC method, the weight- and the number-average molecular weights of these high-volume production chemicals (kiloton per annum), used as synthetic tanning agents, concrete plasticizers, and dispersants, can be determined. Recoveries in IPE range from 73 to 85% in river Rhine water and from 79 to 93% in tap water for n = 2 to n = 7 with limits of detection of 3-8 ng/L for individual homologues from 500 mL of water. The IPE-IPC procedure was applied to samples of secondary industrial effluents, river Rhine water, a river bank filtrate, and a groundwater sample. SNFC up to n = 6 were detected in the treated effluents. Total concentrations ranged from 208 micrograms/L in a secondary treated SNFC production effluent to < 1.4 micrograms/L in groundwater. These first analyses suggest a widespread occurrence of the lower oligomers of SNFC in the aquatic environment.


Assuntos
Formaldeído/análise , Naftalenos/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida , Polímeros/análise , Esgotos/análise , Espectrometria de Massas por Ionização por Electrospray
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