Análises seqüenciais de agrupamentos aplicadas ao estudo de partículas atmosféricas

The present paper has as objective to apply a sequential Cluster Analysis to the atmospheric particles: Hierarchical Cluster Analysis followed by Nonhierarchical Cluster Analysis. The hierarchical cluster analysis results were used as start point for the nonhierarchical cluster analysis as an agglomerative technique. These particles were taken from two areas of the metropolitan region of Porto Alegre, Charqueadas and Sapucaia do Sul., from may /97 to may/98, using a High Volume Sampler (Hi-Vol). Around 10,000 particles were analysed by Scanning Electron Microscope with Energy-Dispersive X-Ray microanalysis (SEM-EDS). The Hierarchical Cluster Analysis allowed the identification of five groups of particles, whose amounts were differentiated according to the summer and the winter campaigns. The abundance of each type of particles inside each group according to the different sections was verified by the Nonhierarchical Cluster Analysis, resulting in information about the emissions sources. The groups of particles of Si/Al and Si and of Fe/Zn and Fe for Charqueadas were more significant in section 2 and 3 (NW and W wind directions) and in section 1 (SE wind direction), evidencing the influence of the coal power plant and steel industry, respectively located in these quadrants. In Sapucaia do Sul the data were more heterogeneous, causing a certain difficulty to identify the source as anthropogenic. Nevertheless the group of particles containing Fe was found in sectors of NW/W wind directions which shows the influence of the steel plant.

Analytical challenges in breath analysis and its application to exposure monitoring

There is an increasing interest in the use of breath analysis for monitoring human physiology and exposure to toxic substances or environmental pollutants. This review focuses on the current status of the sampling procedures, collection devices and sample-enrichment methodologies used for exhaled breath-vapor analysis. We discuss the different parameters affecting each of the above steps, taking into account the requirements for breath analysis in exposure assessments and the need to analyze target compounds at sub-ppbv levels. Finally, we summarize the practical applications of exposure analysis in the past two decades

Composição iônica majoritária de águas de chuva no centro da cidade de São Paulo

The chemical composition of rainwater samples collected from March 2002 to February 2003 in downtown São Paulo city (Universidade Presbiteriana Mackenzie) is presented. Potentiometric and conductimetric measurements were used to evaluate the [H+] and the total ionic content. Major anions and cations were determined by ion chromatography with conductivity detection. The rainwater was acidic with a mean pH of 4.99. The volume weighted means, VWM, of the anions nitrate, acetate and sulfate were, respectively, 21.2, 16.9 and 12.4 µmol L-1. Ammonium was the most abundant ion with a VWM of 37.6 µmol L-1. The contribution of each anion to the free acidity potential decreases in the following order: SO4(2-) (28.8%), CH3COO- (24.7%), NO3- (22.8%), Cl- (13.4%), HCOO- (7.7%) and C2O4(2-) (2.5%). The relative contribution of the weak organic acids to the free acidity was significant, 34.9%.

Composição química da chuva e aporte atmosférico na Ilha Grande, RJ

Wet (n = 21) and dry (n = 23) deposition samples were collected from March to September 2002 at the southern coast of Ilha Grande. Rainwater pH varied from 4.3 to 6.3 and ionic concentrations (in µmol L-1) decreased in the order Cl- > Na+ > Mg2+ > SO4(2-) > NO3- ~ NH4+ > K+ ~ H+ > Ca2+. Scavenging of sea-salt aerosols was the major source of Cl-, Na+, Mg2+, and Ca2+. Half of total SO4(2-) was non-sea-salt SO4(2-). Total deposition fluxes of NH4+, NO3-, and non-sea-salt SO4(2-) were respectively 9.3, 17.8, and 16.0 mol ha-1 month-1.

Influência de poluentes atmosféricos em Belo Jardim (PE) utilizando Cladonia verticillaris (líquen) como biomonitor

Cladonia verticillaris used in this study was collected in the cerrado vegetation of Saloá (PE, Brazil) and transplanted in plastic containers on soil from the collection place to Belo Jardim (PE) that possesses lead smelters and battery industries. The experiments were disposed at eleven different places for evaluating the dispersion of pollutants and their effects on the biomonitor. The exposed lichens were collected over eight months and submitted to thin layer and high performance liquid chromatographies, and scanning electron microscopy. C. verticillaris placed in the vicinity of the emission sources demonstrated alteration in its metabolism, decreasing the production of its major compound, fumarprotocetraric acid, and deterioration of its external and internal surfaces.

Principais carbonilas no ar de locais públicos no Rio de Janeiro

An air quality evaluation of indoor environments with focus on lower carbonyls was carried out in 50 public places using TO-11A methodology. Formaldehyde levels (ranging from 12.5 to 1034 mg m-3) were above the threshold limit in 49 of 50 analyzed samples while acetaldehyde (ranging from 5.2 to 840 mg m-3) and acetone (ranging from 5.5 to 4839 mg m-3) were respectively bellow the limits of OSHA and NIOSH in all samples. However all samples were bellow the threshold limits suggested by the Brazilian legislation - NR-15. A correlation study between the carbonyls and temperature and humidity was also done.

Bioprocessos para remoção de dióxido de carbono e óxido de nitrogênio por micro-algas visando a utilização de gases gerados durante a combustão do carvão

The aim of this work was to study the removal of CO2 and NO by microalgae and to evaluate the kinetic characteristics of the cultures. Spirulina sp. showed µmax and Xmax (0.11 d-1, 1.11 g L-1 d-1) when treated with CO2 and NaNO3. The maximum CO2 removal was 22.97% for S. obliquus treated with KNO3 and atmospheric CO2. The S. obliquus showed maximum NO removal (21.30%) when treated with NO and CO2. Coupling the cultivation of these microalgae with the removal of CO2 and NO has the potential not only to reduce the costs of culture media but also to offset carbon and nitrogen emissions.

Parâmetros bioquímicos foliares das espécies Licania tomentosa (Benth.) e Bauhinia forficata (Link.) para avaliação da qualidade do ar

Foliar analysis of biochemical parameters were carried out in order to investigate the influence of air pollutants on two tropical tree species (Licania tomentosa (Benth.) and Bauhinia forfícata (Link.)). Special attention was given to tropospheric ozone due to the fact that concentration levels in the region were found to be up to 140 µg m-3 for a 4 h average time, which is well above the value that can cause injuries to orchides and tobacco (59 µg m-3). Other pollutants such as nitrogen and sulphur oxides were measured and their ambient concentrations were also associated to biochemical alterations in the investigated species.

Avaliação de metais traços e íons majoritários em águas de chuva na cidade de São Paulo

Rainfall samples collected in the downtown area of São Paulo city, during 2003, exhibited average concentrations of cadmium, lead and copper of 1.33, 8.52 and 49.5 nmol L-1, respectively. Among the major ions, NH4+ was the predominant species followed by NO3-, SO4(2-) and Ca2+, with volume weighed mean (VWM) concentrations of 37.1, 20.1, 11.9 and 10.8 µmol L-1, respectively. All the determined species showed high inter-events variability, including free H+ ions whose VWM concentration was 4.03 µmol L-1, corresponding to a pH value of 5.39.

Composição química das águas pluviais e deposição atmosférica anual na bacia do Alto Sorocaba (SP)

Two sampling points were chosen and forty samples were collected between January and December 2006 at Alto Sorocaba basin. The rainwater pH varied from 5.46 to 6.36 (Ibiúna) and 5.26 to 6.81 (Itupararanga), being Ca2+ the main ion responsible for controlling the rainwater pH. The ionic concentrations decreased in the following order: Ca2 +>Na+> Mg2+>K+ for cations and SO4(2-)>HCO3->NO 3->Cl- >PO4(3-) for anions. The annual atmospheric deposition appeared to be controlled mostly by following sources: mining activities and cement factories (Ca2+ and HCO3-), natural soil dust (Na+, Mg2+ and HCO3-), fossil fuel burning (SO4(2-)) and agriculture activities (K+, NO3- and PO4(3-)).

Inventário de emissão de fontes veiculares da Região Metropolitana de Campinas, São Paulo

The degradation of air quality in great urban centers is noted by frequent critical episodes of air pollution and public health issues, and vehicles are a great source of pollutant emissions, mainly derived from combustion processes. A database is needed to direct mitigation of emissions. The main objective of this work is to present it as an emissions inventory. The results show that vehicular sources of CO, HC and NOx represent over 75% of total emissions in the MRC. Besides, the proposed methodology presented results consistent with the literature

Impacto ambiental de kartódromos situados na cidade do Rio de Janeiro: monitoramento de BTEX no ar e do nível de ruído

In this work, noise and aromatic hydrocarbons levels of indoor and outdoor karting circuits located in Rio de Janeiro were assessed. The sampling was perfomed using active charcoal cartridges, followed by solvent desorption and analysis by gas chromatography with mass spectrometry detection. This study demonstrated that the karting circuits, venues for entertainment, were a major source of air pollution with the detection of considerable amounts of these compounds (2.0 to 19.7 µg m-3 of benzene; 4.1 to 41.1 µg m-3 of toluene; 2.8 to 36.2 µg m-3 of ethylbenzene; 0.7 to 36.2 µg m-3 of xylenes) and high noise levels.

Câmara de volatilização: uma alternativa para avaliação da eficiência de amostragem de α- e β-endossulfam em fase gasosa

The efficiency of XAD®-2 resin in sampling the pesticides α and β-endosulfan from air contaminated in the laboratory was evaluated. Sampling efficiency ranged from 87 to 108% for α-endosulfan and from 71 to 84% for β-endosulfan with relative standard deviation lower than 19%. The pesticides were not detected in the second section of the cartridge showing the good retention capacity of XAD®-2 for these analytes. Method quantification limits were 0.32 and 0.34 µg m-3 for α and β-endosulfan, respectively. These results suggest that the proposed method may be useful for evaluating occupational exposure to these compounds.

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Energy Supply of Detached Houses in Russia and Finland

The problem of choosing the heating system is always relevant when building new houses. Type of energy source (solid fuel, liquid fuel, gas, electricity, alternative sources) is the main issue in choosing the heating system. The work gives a comprehensive overview of heating methods, determines their advantages and disadvantages taking into account economical and ecological situations in Finland and Russia. Quantitative contribution of single Finnish and Russian detached houses in the overall level of carbon dioxide emissions is estimated when using each method. Comparison of Russian and Finnish energy markets and their impact on electricity pricing is made in the work. The influence of air pollution on environmental offsets according to Russian and Finnish legislative and normative acts is determined.