O presente estudo avaliou a bioacumulação de tributilestanho (TBT) pelo siri azul (Callinectes sapidus). Os animais foram alimentados com comida contaminada com 30 µg g-1 de TBT, expresso como Sn. Os analitos foram determinados nas brânquias, hepatopâncreas e músculo. Realizou-se uma digestão ácida para determinação da concentração total de Sn, e a técnica de extração em fase sólida foi utilizada para determinação seletiva de TBT. Obteve-se limites de detecção de 44,6 e 4,46 ng g-1 para HG-ICP OES (geração de hidretos (HG) por espectrometria de emissão óptica com plasma indutivamente acoplado) e ICP-MS (ICP-espectrometria de massas), respectivamente. Os resultados para os tecidos dos animais não contaminados foram inferiores a 50 ng g-1, enquanto os submetidos à alimentação contaminada mostraram elevadas concentrações de Sn (até 6229 ng g-1) e TBT (até 3357 ng g-1) relacionadas aos dias de exposição. De acordo com os resultados, Sn é acumulado pelo siri azul em elevadas concentrações no hepatopâncreas. Para a maioria dos animais, os resultados sugerem que o Sn é bioacumulado como TBT.

This study evaluated the bioaccumulation of tributyltin (TBT) by the blue crab (Callinectes sapidus). Animals were fed with contaminated food containing 30 µg g-1 of TBT expressed as Sn. The analytes were determined in the gills, hepatopancreas and muscle. Acid digestion was used in the total Sn determination, and a solid-phase extraction technique was used for the selective determination of TBT. Limits of detection of 44.6 and 4.46 ng g-1 were found for HG-ICP OES (hydride generation-inductively coupled plasma optical emission spectroscopy) and ICP-MS (ICP-mass spectrometry), respectively. The results for non-contaminated animals were below 50 ng g-1, while the animals subjected to the contaminated food showed higher tissue concentrations of Sn (until 6229 ng g-1) and TBT (until 3357 ng g-1) related to the number of exposure days. According to the results, Sn is bioaccumulated by the blue crab in higher concentrations in the hepatopancreas. For most of these animals, the results suggest that Sn is bioaccumulated as TBT.

Foi avaliada a bioconcentração de cádmio e chumbo pelo caranguejo fluvial Trichodactylus fluviatilis. Trinta animais foram expostos a 200 µg L-1 de cádmio e chumbo por 7, 14 e 21 dias. Após dissecação e digestão nitro-perclórica, os metais foram determinados nas brânquias, hepatopâncreas e músculo por espectrometria de emissão óptica com plasma acoplado indutivamente. O chumbo foi detectado apenas nas brânquias, sem diferenças significativas entre diferentes períodos de exposição. O cádmio foi encontrado em todos os tecidos após exposição. Diferenças significativas entre as concentrações de cádmio em animais expostos por diferentes períodos sugerem um processo de acumulação, com concentração estabilizada após 14 dias. Usando um procedimento de extração em fase sólida com Saccharomyces cerevisae e com o objetivo de avaliar a transferência e estocagem de cádmio nos tecidos, foi realizado o fracionamento de cádmio na forma livre (ou lábil) e cádmio-proteína (possivelmente metalotioneína) (Cd-P) em animais expostos a 200 µg L-1 de cádmio por 21 dias. A determinação de cádmio livre e Cd-P nos tecidos mostrou que nas brânquias o metal foi encontrado principalmente na forma livre, enquanto que no hepatopâncreas o metal foi encontrado principalmente ligado à proteína. Pode-se inferir que, absorvido através das brânquias, o cádmio foi transferido e estocado no hepatopâncreas dos animais.

The bioconcentration of cadmium and lead by the freshwater crab Trichodactylusfluviatilis was evaluated. Thirty animals were exposed to 200 µg L-1 of cadmium and lead for 7, 14 and 21 days. Both metals were determined in gills, hepatopancreas and muscle after dissection and digestion by inductively coupled plasma optical emission spectrometry. Lead was detected only in gills, but without significant difference among different exposure periods. Cadmium was found in all tissues after exposure. Significant differences among cadmium concentrations in animals exposed for different periods suggest an accumulation process, with concentration stabilized after 14 days. Fractionation of free (or labile) cadmium and cadmium protein (possibly metallothionein) (Cd-P) in gills and hepatopancreas were carried out to assess the cadmium transference and storage in the tissues using a solid phase extraction procedure with Saccharomycescerevisae. Fractionation of free (or labile) cadmium and cadmium protein (possibly metallothionein) (Cd-P) in animals exposed to 200 µg L-1 for 21 days in gills and hepatopancreas were carried to assess the cadmium transference and storage in the tissues using a solid phase extraction procedure with Saccharomycescerevisae. In gills, cadmium was found mainly in the free form, while in hepatopancreas the metal was found mainly bound to the protein (Cd-P). It may be inferred that, absorbed through gills, cadmium was transferred and stored in the hepatopancreas.

Simultaneous measurements of outdoor and indoor pollution were performed at three schools in Lisbon. Volatile organic compounds (VOCs), formaldehyde and NO2 were passively monitored over a two-week period. Bacterial and fungal colony-forming units and comfort parameters were also monitored at classrooms and playgrounds. The highest indoor levels of CO2 (2666 μg/m³), NO2 (40.3 μg/m³), VOCs (10.3 μg/m³), formaldehyde (1.03 μg/m³) and bioaerosols (1634 CFU/m³), and some indoor/outdoor ratios greater than unity, suggest that indoor sources and building conditions might have negative effects on air indoors. Increasing ventilation rates and use of low-emission materials would contribute towards improving indoor air quality.

A method for selective determination of tributyltin in the presence of Sn(IV) by combining hydride generation inductively coupled plasma optical emission spectrometry (HG-ICP OES) and solid phase extraction (SPE) using baker's yeast is proposed. The procedure is based on selective retention of TBT by the yeast at pH = 6. Detection limit of 1.9 µg L-1 and quantification limit of 6.3 µg L-1 were obtained. TBT and San(IV) were determined in the range of 0-25 µg L-1 and the proposed approach was applied to analyze river water, sea water and biological extracts, with recoveries of 114, 101 and 86%, respectively.