Avaliação da poluição atmosférica oriunda de indústria cimenteira e impacto na saúde

A população dos povoados Machado, Estivas e Estivas II, localizados em Laranjeiras, e Nossa Senhora do Socorro, Sergipe, região na qual está inserido um grande complexo industrial cimenteiro, sofre com a poluição do ar produzida por estas indústrias. O objetivo deste trabalho é avaliar o risco da exposição humana às emissões atmosféricas poluentes deste complexo industrial cimenteiro, por meio de biomonitoramento passivo, utilizando cascas de árvores presentes na região de estudo como bioindicadores, como alternativa de monitoramento abrangente, preciso e de baixo custo de poluentes do ar. Para esta proposta, concentrações de elementos químicos foram determinadas pela técnica do EDXRF, nas cascas de árvores. Foram calculados os fatores de enriquecimento para os elementos encontrados nas cascas da região em estudo, com o objetivo de verificar aqueles que são de inserção de atividades antropogênicas. Mapas de atenuação das concentrações dos elementos foram feitos com o intuito de identificar “hor spots” e de conhecer a mobilidade do elemento no ar.Foram coletados dados de saúde da população nos postos de saúde dos povoados Machado, Estivas e Estivas II . Dados de saúde dos pacientes do povoado Oiteiros, localizado em Nossa Senhora do Socorro e livre das emissões aéreas das indústrias de cimento foram coletados no posto de saúde local para comparação com os dados de saúde dos povoados impactados pelas cimenteiras. Os resultados mostram que é necessário, que sejam efetuados estudos epidemiológicos, importantes para proteção da saúde e estabelecimento de medidas mitigadoras para esta população exposta às concentrações mais elevadas de poluentes

A new cement slurry modified with chitosan/alginate interpenetrating networks and hydroxyapatite -- structural characteristics after long-term contact with hyper-saline produced water from oil well operations

Oil is an important source of energy, mainly in developing countries. Important research has been conductedto find cementing procedures that guarantee safe and cost-effective oil exploration below pre-salt layers. Thiswork aimed to make a new cement paste with cement, seawater, silica, biopolymers (chitosan and sodiumalginate) and hydroxyapatite (HA), found in nature. For comparison purposes, slurry without additives wasprepared and characterized. The HA used was extracted from fish scales (Cynoscion acoupa) in optimizedcondition NaOH concentration, temperature and reaction time. Both slurry were prepared with ratioswater/cement (w/c) and silica/cement (s/c) equal to 0.50 and 0.35, respectively. The new cement slurry wasobtained with proportions of 5% of each biopolymer and HA with respect to the total weight of the cement.In the immersion tests, specimens were immersed in samples of hyper production of saline water by 35°C for15 days. Thereafter, they were washed, dried and its surface layers were scraped. Before, the resultingmaterials were characterized. The values of the ratios Ca/Si of new cement slurry (3.38 À 0.06) were superiorcompared to standard (2.58 À 0.05). The new slurry had high thermal stability and low amounts of smallcrystallite-type portlandite (35.70 nm). Conversely, a slurry standard formed larger crystals of about 50.3 nm.Significantly, after continuous long-term contact of both slurries with hyper-saline produced water from oilwell fields operations, in comparison with standard slurry structural characteristics, the new slurry haspractically maintained its pristine chemical structure, as well as has shown crystallite-type particles of NaCland Friedel's/Kuzel's salts with lower proportion. The presence of the biopolymers and HA has driven theimproved the self-healing properties observed in the new cement slurry. In this first study, the new slurry hasshown adequate characteristics to contribute to cost effective and environmental-friendly oil well operations

Concentrações e associações geoquímicas de Pb e Zn em sedimentos do rio São Francisco impactados por rejeitos da produção industrial de zinco Concentrations and geochemical associations of Pb and Zn in sediments of the river São Francisco impacted by wastes from industrial zinc production

<abstract language="eng">Surface sediments from the River São Francisco were analyzed to investigate the impact, due to the presence of metals (Cd, Cu, Pb, Zn) in wastes from a metallurgical industry in the city of Três Marias/MG, Brazil. The concentrations and geochemical associations of Pb, Zn and trace metals associated with the minerals employed in zinc production were measured. Sediments close to discharge locations were highly contaminated with Pb (332-512 &#956;g g-1) and Zn (7872-10780 &#956;g g-1), with values decreasing rapidly due to dilution and hydraulic sorting. Evaluation of toxicity according to the Consensus-based Sediment Quality Guidelines indicated for Cd, Pb and Zn a high probability of adverse effects on aquatic biota at these sites

Multivariate optimization of an analytical method for the analysis of dog and cat foods by ICP OES

AbstractExperimental design methodology was used to optimize an analytical method for determination of the mineral element composition (Al, Ca, Cd, Cr, Cu, Ba, Fe, K, Mg, Mn, P, S, Sr and Zn) of dog and cat foods. Two-level full factorial design was applied to define the optimal proportions of the reagents used for microwave-assisted sample digestion (2.0molL−1 HNO3 and 6% m/v H2O2). A three-level factorial design for two variables was used to optimize the operational conditions of the inductively coupled plasma optical emission spectrometer, employed for analysis of the extracts. A radiofrequency power of 1.2kW and a nebulizer argon flow of 1.0Lmin−1 were selected. The limits of quantification (LOQ) were between 0.03μgg−1 (Cr, 267.716nm) and 87μgg-1 (Ca, 373.690nm). The trueness of the optimized method was evaluated by analysis of five certified reference materials (CRMs): wheat flour (NIST 1567a), bovine liver (NIST 1577), peach leaves (NIST 1547), oyster tissue (NIST 1566b), and fish protein (DORM-3). The recovery values obtained for the CRMs were between 80±4% (Cr) and 117±5% (Cd), with relative standard deviations (RSDs) better than 5%, demonstrating that the proposed method offered good trueness and precision. Ten samples of pet food (five each of cat and dog food) were acquired at supermarkets in Aracaju city (Sergipe State, Brazil). Concentrations in the dog food ranged between 7.1mgkg−1 (Ba) and 2.7gkg−1 (Ca), while for cat food the values were between 3.7mgkg−1 (Ba) and 3.0gkg−1 (Ca). The concentrations of Ca, K, Mg, P, Cu, Fe, Mn, and Zn in the food were compared with the guidelines of the United States’ Association of American Feed Control Officials (AAFCO) and the Brazilian Ministry of Agriculture, Livestock, and Food Supply (Ministério da Agricultura, Pecuária e Abastecimento—MAPA)