Synthesis of functionalized mesoporous material from rice husk ash and its application in the removal of the polycyclic aromatic hydrocarbons

Environmental Science and Pollution Research - The rice husk ash (RHA) was used as an alternative source of silica for the synthesis of the functionalized mesoporous material, which was used in the...     

“Modern agriculture” transfers many pesticides to watercourses: a case study of a representative rural catchment of southern Brazil

Environmental Science and Pollution Research - The total cultivated area in Brazil reached to 62 million ha in 2018, with the predominance of genetically modified soybean and corn (36 and 17...     

Distribution of genetic elements associated with antibiotic resistance in treated and untreated animal husbandry waste and wastewater

Environmental Science and Pollution Research - Animal breeding for meat production based on swine, cattle, poultry, and aquaculture is an activity that generates several impacts on the environment,...     

Diel Variability of Water Quality in a Tropical Polluted Bay

The objective is to describe and quantify the diel variability of water quality in a tropical coastal system, Guanabara Bay, Brazil. Water samples were collected in spring and neap tide cycles over 24 h periods at three strategic sites. A pollution gradient was evident between the sampling sites. The average fecal coliform values decreased from 10⁶ (site 3, most polluted) to 10¹ (site 1, less polluted). Organic matter mineralization was found in a similar gradient to organic pollution. However, complete nitrification was only found associated to regions where the water quality was better. Variability in this data set was determined mostly by the pollution gradient observed, and by tidal influence as well. The poor water quality indicates that the bay undergoes severe environmental stress. However water renewal promoted by tidal action was an important mechanism in diluting the pollution, improving water quality even in ebb tides and in the inner channels. The significance of micro-scale changes in water quality assessment in Guanabara Bay was confirmed, as well as the importance of these strategic sampling sites, reinforcing the importance of these measurements in monitoring programs.     

Pharmaceutical compound removal efficiency by a small constructed wetland located in south Brazil

Environmental Science and Pollution Research - The fate of pharmaceuticals during the treatment of effluents is of major concern since they are not completely degraded and because of their...     

Health impact assessment of air pollutants during the COVID-19 pandemic in a Brazilian metropolis

Environmental Science and Pollution Research - Studies around the world have revealed reduced levels of atmospheric particulate matter in periods of greatest human mobility restriction to contain...     

Relationships between fecal indicators and pathogenic microorganisms in a tropical lagoon in Rio de Janeiro, Brazil

Rodrigo de Freitas Lagoon is an urban ecosystem undergoing accelerated degradation, therefore selected as a model for microbiological quality studies of tropical lagoons. The aim of this study was to evaluate the abundance and the spatial distribution of fecal pollution indicators and pathogenic microorganisms in the lagoon. The relationships between microbial groups and abiotic measurements were also determined to evaluate the influence of environmental conditions on bacterial distribution and to identify the capability of coliforms and Enterococcus to predict the occurrence of Vibrio, Staphylococcus aureus, and Salmonella. Surface water samples were collected monthly, from December 1999 to October 2000. Analyses were performed by traditional culture techniques. A uniform spatial distribution was observed for all bacterial groups. The fecal pollution indicators occurred in low abundances while potentially pathogenic microorganisms were consistently found. Therefore, our study supported the use of counts of coliforms and Enterococcus to indicate only recent fecal contamination.     

Bacterial communities of the marine sponges Hymeniacidon heliophila and Polymastia janeirensis and their environment in Rio de Janeiro, Brazil

In this study we performed a survey of the bacterial communities associated with the Western Atlantic demosponges Hymeniacidon heliophila and Polymastia janeirensis, based on 16S rRNA sequencing and transmission electron microscopy (TEM). We compared diversity and composition of the sponge-associated bacteria to those of environmental bacteria, represented by free-living bacterioplankton and by bacteria attached to organic particulate matter in superficial sediments. Partial bacterial 16S rRNA sequences from seawater, sediment, and sponges were retrieved by PCR, cloning, and sequencing. Sequences were subjected to rarefaction analyses, phylogenetic tree construction, and LIBSHUFF quantitative statistics to verify coverage and similarity between libraries. Community structure of the free-living bacterioplankton was phylogenetically different from that of the sponge-associated bacterial assemblages. On the other hand, some sediment-attached bacteria were also found in the sponge bacterial community, indicating that sponges may incorporate bacteria together with sediment particles. Rare and few prokaryotic morphotypes were found in TEM analyses of sponge mesohyl matrix of both species. Molecular data indicate that bacterial richness and diversity decreases from bacterioplankton, to particulate organic sediment, and to H. heliophila and P. janeirensis. Sponges from Rio de Janeiro harbor a pool of novel and exclusive sponge-associated bacterial taxa. Sponge-associated bacterial communities are composed of both taxons shared by many sponge groups and by species-specific bacteria.     

Radioactivity concentration in liquid and solid phases of scale and sludge generated in the petroleum industry

Scales and sludge generated during oil extraction and production can contain uranium, thorium, radium and other natural radionuclides, which can cause exposure of maintenance personnel. This work shows how the oil content can influence the results of measurements of radionuclide concentration in scale and sludge. Samples were taken from a PETROBRAS unit in Northeast Brazil. They were collected directly from the inner surface of water pipes or from barrels stored in the waste storage area of the E&P unit. The oil was separated from the solids with a Soxhlet extractor by using aguarras at 90+/-5 degrees C as solvent. Concentrations of 226Ra and 228Ra in the samples were determined before and after oil extraction by using an HPGe gamma spectrometric system. The results showed an increase in the radionuclide concentration in the solid (dry) phase, indicating that the above radionuclides concentrate mostly in the solid material.