The metal concentrations in water, sediments and mollusks (Tagelus plebeius) of the Manguaba Lagoon and the influence of humic substances from water and sediments in the distribution of these metals were investigated in this work. The mean metal concentrations in water were: Mg (89.0 ± 0.11), Ca (32.0 ± 0.10), Fe (0.97 ± 0.02), Mn (0.52 ± 0.01), Zn (0.33 ± 0.10) and Pb (0.22 ± 0.02) mg L-1. The Pb concentrations were above the Brazilian legislation limit. All sediment data were below maximum limit established by the National Council for the Environment (CONAMA, Brazil) of the Ministry of the Environment, and the concentration ranges for metals were: Fe (1199-60000), Mg (339-8870), Ca (461-3838), Cr (< LOQ-39.5) and Pb (< LOQ-12.5) mg kg-1 (LOQ: limit of quantification). None of the principal contaminants (Cr, Pb and Cd) was determined in Tagelus plebeius, being a positive fact once the population nearby Manguaba Lagoon consumes large amounts of this mollusk. According to the results, the influence of humic substances in the contaminant retention is evident as they become unavailable for absorption by mollusks of Manguaba Lagoon.

Assessment of phosphorus in fruit juices is of great interest due to its essentiality and nutritional properties. This study applied sample treatment strategies to determine phosphorus in fractions of juices. Firstly, total phosphorus (Ptotal) was determined from digestion and sample suspension exploring direct analysis by inductively coupled plasma optical emission spectrometry, which presented no significant difference, for 95% of confidence level. Then, free phosphorus (Pfree) was determined by spectrophotometry and represented 30-90% of Ptotal with an inverse relationship respecting Ptotal concentration. Fractioning according to particle size evidenced highest fraction of Pfree in samples after filtration. Fractioning of phosphorus based on its charge was also performed and the high percentages of P in the anionic fraction (from 91.2 to 95.9%) are related to free inorganic phosphate in equilibrium with its protonated forms. Thus, it is more assailable after consumption, giving this food great functionality on human diet.

A indústria siderúrgica brasileira consome grandes quantidades de carvão vegetal. As carvoarias são responsáveis por emissões atmosféricas de compostos orgânicos voláteis tais como compostos carbonílicos (CC). Neste trabalho, foram determinados o perfil e as concentrações de CC em fase vapor durante a produção de carvão vegetal a partir de eucalipto. As amostras foram coletadas próximas aos fornos, em cartuchos de sílica revestidos com 2,4-dinitrofenilidrazina e, em seguida, extraídas e analisadas por HPLC-DAD-MS (cromatografia líquida de alta eficiência acoplada a detector de arranjo de diodo e espectrômetro de massas). Doze CC foram identificados e quantificados, entre eles acetaldeído e os pares coeluídos furfural/propanal, acroleína/propanona e 2-pentenal/pentanal. Estes três pares tiveram seus picos resolvidos por meio de espectrometria de massas para doze amostras e individualmente quantificados. Os perfis obtidos indicaram uma maior abundância do par furfural/propanal nas três fases de carbonização, seguido do acetaldeído na primeira fase e do 2-oxobutanal nas segunda e terceira fases. Furfural/propanal e acetaldeído se destacaram dentre os CC determinados nas proximidades dos fornos, com concentrações médias de 4948 e 2558 µg m-3 e concentrações máximas de 11655 e 4805 µg m-3, respectivamente.

Brazilian steel industry consumes huge amounts of charcoal. The charcoal plants are responsible for atmospheric emissions of volatile organic compounds such as carbonyl compounds (CC). In this work, the profile and the concentrations of CC in the vapor phase were determined during the charcoal production from eucalyptus. Samples were collected near kilns on silica cartridges coated with 2,4-dinitrophenylhydrazine, and then extracted and analyzed by HPLC-DAD-MS (high performance liquid chromatography coupled with diode array detector and mass spectrometry). Twelve CC were identified and quantified, amongst them acetaldehyde and the co-eluting acrolein/propanone, furfural/propanal and 2-pentenal/pentanal pairs. These three pairs were peak resolved by mass spectra for twelve samples and thus individually quantified. The profiles obtained indicated the furfural/propanal pair as the most abundant in all three carbonization stages, followed by acetaldehyde in the first stage and 2-oxobutanal in the second and third stages. Furfural/propanal and acetaldehyde stood out among CC determined near the kilns, with average concentrations of 4948 and 2558 µg m-3 and maximum concentrations of 11655 and 4805 µg m-3, respectively.