This paper is the first comprehensive survey of polycyclic aromatic hydrocarbons (PAHs) in coastal sediments in Bahia Blanca, Argentina, and provides useful information on their levels of concentration, composition, and sources of these pollutants. The total concentrations of PAHs ranged from 15 to 10,260 ng g(-1). The highest contents (mean 3,315 ng g(-1)) of total PAHs in marine sediments were found in the inner channels of the estuary, while the lower ones (204 ng g(-1)) belong to samples collected far away from contamination sources. The global average recorded in this study (1,500 ng g(-1)) indicates that the studied area lies within the referenced category of industrialized coastal zones under chronic pollution. The diagenetic PAH contribution was found to be negligible at all sampled locations; however, the calculation of molecular ratios determined an overimposition of pyrolitic PAHs over the petrogenic input. Further, the use of principal components analysis (PCA) clearly separated ring group compounds and enabled the determination of pyrolitic/combustion PAHs dominancy.

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Systematic measurements of both Tributyltin (TBT) and Dibutyltin (DBT) in sediments along different locations in the inner zone of Bahía Blanca estuary were done. Two samples were taken near the main dry dock facility, at Puerto Belgrano naval base, in Argentina. TBT concentrations from non-detected to 170.3 ng Sn g(-1) were measured in the inner region of the estuary, and higher one of 3,288 ng Sn g(-1) near the dry dock at Puerto Belgrano. DBT values ranging between non-detected and 75.2 ng Sn g(-1) were obtained along the principal channel, but extreme concentration of 1,645 ng Sn g(-1) was measured at Puerto Belgrano. These values show that this estuary is affected by organotin pollution, mainly in areas of heavy shipyard activities.

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BHT é um antioxidante usado como aditivo em alguns alimentos e em plásticos de embalagens, e sua presença em água mineral engarrafada é possível devido à migração do aditivo contido nas paredes do recipiente. Planejamento fatorial foi empregado para determinar os valores ótimos para os parâmetros operacionais principais na análise de hidroxitolueno butilado (BHT) em água engarrafada usando microextração em fase sólida (SPME) direta e em headspace na etapa de pré-concentração. Os parâmetros otimizados foram pH, temperatura e força iônica da amostra. A separação, detecção e quantificação dos extratos foi efetuada por cromatografia gasosa acoplada a espectrometria de massas. Experimentos preliminares foram realizados para selecionar a melhor fibra para o procedimento de extração. Fibras de polidimethilsiloxano (PDMS) foram selecionadas, e a metodologia otimizada aplicada com sucesso na extração e quantificação de BHT em amostras reais de água mineral e mineralizada engarrafada.BHT is an antioxidant utilized as additive in some foods and in packaging plastics, and its presence in bottled mineral water is possible due to its migration from bottle walls to the contents. A factorial experimental design was utilized to obtain the optimum values for the main operational parameters in the analysis of butylated hydroxytoluene (BHT) in bottled water using headspace and direct solid-phase microextraction (SPME) in the pre-concentration step. The parameters optimized were sample pH, temperature and ionic strength. The separation, detection and quantitation of the extracts were performed by gas chromatography coupled to mass spectrometry. Preliminary experiments were made to select the best fiber for the extraction procedure. Polydimethylsiloxane (PDMS) fibers were selected, and the optimized methodology was successfully applied to the extraction and quantitation of BHT in real samples of mineral and mineralized bottled water.