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We investigated the effects of metals and physicochemical variables on the microbes and their metabolisms in the sediments of Guarapiranga reservoir, a tropical eutrophic-hypereutrophic freshwater reservoir located in a highly urbanized and industrialized area in Brazil. The metals cadmium, copper, and chromium showed minor contribution to changes in the structure, composition, and richness of sediment microbial communities and functions. However, the effects of metals on the microbiota are increased when taken together with physicochemical properties, including the sediment carbon and sulfur, the bottom water electrical conductivity, and the depth of the water column. Clearly, diverse anthropic activities, such as sewage discharge, copper sulfate application to control algal growth, water transfer, urbanization, and industrialization, contribute to increase these parameters and the metals spatially in the reservoir. Microbes found especially in metal-contaminated sites encompassed Bathyarchaeia, MBG-D and DHVEG-1, Halosiccatus, Candidatus Methanoperedens, Anaeromyxobacter, Sva0485, Thermodesulfovibrionia, Acidobacteria, and SJA-15, possibly showing metal resistance or acting in metal bioremediation. Knallgas bacteria, nitrate ammonification, sulfate respiration, and methanotrophy were inferred to occur in metal-contaminated sites and may also contribute to metal removal. This knowledge about the sediment microbiota and metabolisms in a freshwater reservoir impacted by anthropic activities allows new insights about their potential for metal bioremediation in these environments.

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This paper presents the characterization of municipal solid waste (MSW) randomly collected from two material recovery facilities in São Paulo city, before (input - recyclables) and after (output - rejects) the sorting processes. Geo-environmental and geotechnical tests were performed on shredded samples and a digestion method was applied to detect the metals As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn concentrations using an ICP OES. The objective was to assist future activities of integrated solid waste management and soil pollution. Results showed different particle sizes comparing the input (44.6%) and the output MSW (75.1%) passing through the 100-mm sieve. Organic matter and ash contents indicated the influence of inorganic carbon due to the plastics' presence, with values varying between 6 and 13%. The pH values obtained were neutral and the electrical conductivity of the MSW rejects suggested a higher amount of ions, with values above 1000 µS/cm. Metals analyses show that Cd, Cu, Ni, Pb, and Zn are present in high concentrations, depending on the types of the materials. Standard Proctor compaction curves yielded maximum dry unit weight varying from 6.6 to 10.0 kN/m3 and optimum moisture contents from 20 to 42%. Cohesion ranged from 1.3 to 31.3 kPa and friction angle from 3.2 to 42.9°. The results are comparable with those obtained for other countries using different MSW treatments and contribute to the data basis for MSW from the selective collection, aiming the integrated solid waste management, serving for other countries that adopt MSW sorting and recycling.

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The growth of two species of macrophytes (Lemna minor and Salvinia auriculata) under the effect of a mixture of amoxicillin, caffeine, carbamazepine, dipyrone, ibuprofen, losartan, omeprazole, and tenivastatin was investigated by bioassay. Three concentration levels were utilized in this study (10, 200, and 500 µg L-1) using a growth inhibition test based on the OECD 221/2006 guidelines. The frond number, total area, and chlorophyll a level were selected as suitable end points. For L. minor, at all concentrations, a significant difference in the total frond number was observed and the growth inhibition varied from 30 to 70% at the low and high concentrations, respectively. No significant growth change was observed to S. auriculata exposed to the mixture of drugs. Thus, individual drug tests were performed for L. minor which demonstrated stimulation in growth, when exposed to most drugs individually, except tenivastatin which was identified as the drug responsible for the significant growth inhibition seen in the mixture. The L. minor enhanced growth was probably caused by N molecule transformation to ammonium and nitrate, essential nutrients for plants.

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Freshwater reservoirs emit greenhouse gases (GHGs) such as methane (CH4) and carbon dioxide (CO2), contributing to global warming, mainly when impacted by untreated sewage and other anthropogenic sources. These gases can be produced by microbial organic carbon decomposition, but little is known about the microbiota and its participation in GHG production and consumption in these environments. In this paper we analyzed the sediment microbiota of three eutrophic tropical urban freshwater reservoirs, in different seasons and evaluated the correlations between microorganisms and the atmospheric CH4 and CO2 flows, also correlating them to limnological variables. Our results showed that deeper water columns promote high methanogen abundance, with predominance of acetoclastic Methanosaeta spp. and hydrogenotrophs Methanoregula spp. and Methanolinea spp. The aerobic methanotrophic community was affected by dissolved total carbon (DTC) and was dominated by Crenothrix spp. However, both relative abundance of the total methanogenic and aerobic methanotrophic communities in sediments were uncoupled to CH4 and CO2 flows. Network based approach showed that fermentative microbiota, including Leptolinea spp. and Longilinea spp., which produces substrates for methanogenesis, influence CH4 flows and was favored by anthropogenic pollution, such as untreated sewage loads. Additionally, less polluted conditions favored probable anaerobic methanotrophs such as Candidatus Bathyarchaeota, Sva0485, NC10, and MBG-D/DHVEG-1, which promoted lower gaseous flows, confirming the importance of sanitation improvement to reduce these flows in tropical urban freshwater reservoirs and their local and global warming impact.

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Shallow urban polluted reservoirs at tropical regions can be hotspots for CO2 and CH4 emissions. In this study, we investigated the relationships between eutrophication and GHG emissions in a highly urbanized tropical reservoir in São Paulo Metropolitan Area (Brazil). CO2 and CH4 fluxes and limnological variables (water and sediment) were collected at three sampling stations classified as hypereutrophic and eutrophic. Analysis of variance (ANOVA) and the principal component analysis (PCA) determined the most significant parameters to CO2 and CH4 fluxes. ANOVA showed significant differences of CO2 and CH4 fluxes between sampling stations with different trophic state. The hypereutrophic station showed higher mean fluxes for both CO2 and CH4 (5.43 ± 1.04 and 0.325 ± 0.167 g m-2 d-1, respectively) than the eutrophic stations (3.36 ± 0.54 and 0.060 ± 0.005 g m-2 d-1). The PCA showed a strong relationship between nutrients in the water column (surface and bottom) and GHG fluxes. We concluded that GHG fluxes were higher whenever the trophic state increases as observed previously in temperate and tropical reservoirs. High concentrations of nutrients in the water column in the studied area support the high production of autotrophic biomass that, when sedimented, ends up serving as organic matter for CH4 producers. These outcomes reinforce the necessity of water quality improvement and eutrophication mitigation in highly urbanized reservoirs in tropical regions.

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Amoxicillin (AMX) is one of the most widely used antibiotics in the world and its presence in wastewater is of great concern for its potential to bacteria selection. However, there is still a gap about the toxicity effect of AMX in nitrifier biomass from activated sludge (AS). This study is based on the implementation of respirometric tests in batches in order to evaluate the toxic effluent toxicity in the nitrification process of AS. The tests were conducted by comparing respiration rates with effluent containing ammonia nitrogen (NH4+-N) and nitrite nitrogen (NO2--N) called "reference" and batches containing toxic effluent doped with different concentrations of AMX here called "process." Results with effluent containing concentrations greater than 100 mg L-1 showed that AMX negatively affected the specific growth rate (µm) of ammonia-oxidizing bacteria (AOB) (from 0.50 d-1 to 0.13 d-1) and nitrite-oxidizing bacteria (NOB) (from 0.64 d-1 to 0.15 d-1). Although there is no total inhibition of populations, these µm values are limiting for a feasible development of the nitrification process in AS systems. The removal of AMX decreased from 99 to 37% (liquid phase) when the concentration of AMX increased (20 mg L-1 to 200 mg L-1). A decrease in the microbial community AOB and NOB was observed through fluorescent in situ hybridization (FISH), corroborating the results of respirometry. In summary, the study showed that the inhibition of the AS nitrification process occurs in the presence of high concentrations of AMX and the most susceptible group are the NOB.

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[This corrects the article DOI: 10.3389/fmicb.2021.647921.].

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This article aims to map the urban climate in the ABC Paulista (ABCP) region, which is located in the southeast area of the Metropolitan Region of São Paulo (MRSP), Brazil. More than 80% of the ABCP urban area comprises the municipalities of Santo André (SA), São Bernardo do Campo (SBC), São Caetano do Sul (SCS), Mauá (MA), Diadema (DIA), and Ribeirão Pires. Considering a four-year dataset (2015-2018), higher urban heat island (HI) intensities were found in the spring (3.7 °C) and summer (3.2 °C), in DIA and SCS, and these HI intensities were associated with extreme thermal discomfort in the afternoon. More intense and concentrated rainfall patterns over a shorter period were identified in ABCP, especially in DIA and SCS. An analysis of O3 and PM10 at fixed pollutant monitoring stations identified SBC as having the largest number of days with O3 concentrations beyond the standards; meanwhile, SCS significantly exceeded the PM10 standards. The traffic and transportation simulation tool, Equilibre Multimodal/Multimodal Equilibrium which was used to estimate emissions from mobile sources, identified SCS as having the highest emissions rates for CO2, CO, HC and PM10. Analysis of the rainwater composition in Capuava (located along boundary of SA and MA) and Paranapiacaba (an environmental preservation area of SA) identified that a major contribution of strong acids and heavy metals in Capuava possibly originated from the Capuava Petrochemical Complex. Meanwhile, the main source of pollutants in Paranapiacaba was from the industrial city of Cubatão. Principal component analysis identified the first three components, which explained 80.7% of the total variance of the data and the main urban climate processes. The HI intensity was associated with thermal discomfort; moreover, the PCA showed the inverse correlation between the number of days that O3 and PM10 exceeded the limits with low relative humidity and no precipitation.

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Membrane bioreactors (MBRs) are one of the treatment technologies with the potential to remove emerging compounds from wastewater. The present work evaluated the efficiency of an MBR pilot system in removing amoxicillin from synthetic wastewater using a continuous flow pre-denitrification MBR (A/O-MBR) pilot unit. The system operated in three phases: (1) synthetic wastewater and hydraulic retention time (HRT) of 40 h; (2) adding amoxicillin 100 µg L-1 to the influent, and (3) varying flowrate to HRT of 20 h. Liquid chromatography coupled to high resolution mass spectrometry analysis confirmed the presence of five amoxicillin degradation by-products in the effluent. The addition of amoxicillin did not affect chemical oxygen demand (COD) or dissolved organic carbon (DOC) removal efficiencies. Respirometry showed that amoxicillin level did not inhibit heterotrophic bacteria metabolism. The change in HRT reduced the DOC removal (from 84% to 66%) but did not influence COD (>94%) or total nitrogen (>72%). The amoxicillin and by-products removal decreased from 80% to 54% with HRT change. Adsorption and biodegradation represented the largest removed fraction of the antibiotic in the A/O-MBR system (68%). Ecotoxicity assays showed P. fluorescens was more resistant and E. coli less resistant to amoxicillin residues at effluent sample matrix.

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Many studies have been conducted on the evaluation and monitoring of micropollutants and by-products in wastewater treatment plants. Considering the increase in the production and consumption of emerging contaminants, such as drugs, personal care products, and plasticisers, it is necessary to conduct studies that support the elaboration of laws and regulations that promote the environmentally sustainable use of sludge and effluents. In this work, the biological degradation of amoxicillin was studied under two anaerobic conditions: i) using a 6 L reactor operated under semi-continuous flow; and ii) a batch system with 100 mL sealed glass syringes. According to the statistical analysis, amoxicillin was completely removed from the systems, but biogas production inhibition was observed (p < 0.05). Liquid chromatography-high-resolution mass spectrometry analysis identified amoxicillin penicilloic acid, amoxilloic acid, amoxicillin diketopiperazine and phenol hydroxypyrazine as by-products under anaerobic conditions. Ecotoxicity tests on effluent treated under the batch conditions showed that the addition of higher amounts of amoxicillin inhibited the target species Aliivibrio fischeri and Raphidocelis subcaptata, causing functional decreases of 28.5% and 22.2% when the antibiotic concentration was 2500 µg L-1. A. fischeri was the most sensitive organism to effluent treated under semi-continuous flow conditions; a continuous reduction in bioluminescence of up to 88.8% was observed after 39 days of feeding, which was associated with by-products accumulation due to unbalanced conditions during anaerobic digestion. Changes in the physico-chemical characteristics of the effluent caused the accumulation and removal of AMX-DKP IV and modified the toxicity to Lactuca sativa and R. subcapitata.

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Ammonia is a key alkaline species, playing an important role by neutralizing atmospheric acidity and inorganic secondary aerosol production. On the other hand, the NH3/NH4 (+) increases the acidity and eutrophication in natural ecosystems, being NH3 classified as toxic atmospheric pollutant. The present study aims to give a better comprehension of the nitrogen content species distribution in fine and coarse particulate matter (PM2.5 and PM2.5-10) and to quantify ammonia vehicular emissions from an urban vehicular tunnel experiment in the metropolitan area of São Paulo (MASP). MASP is the largest megacity in South America, with over 20 million inhabitants spread over 2000 km(2) of urbanized area, which faces serious environmental problems. The PM2.5 and PM2.5-10 median mass concentrations were 44.5 and 66.6 µg m(-3), respectively, during weekdays. In the PM2.5, sulfate showed the highest concentration, 3.27 ± 1.76 µg m(-3), followed by ammonium, 1.14 ± 0.71 µg m(-3), and nitrate, 0.80 ± 0.52 µg m(-3). Likewise, the dominance (30 % of total PM2.5) of solid species, mainly the ammonium salts, NH4HSO4, (NH4)2SO4, and NH4NO3, resulted from simulation of inorganic species. The ISORROPIA simulation was relevant to show the importance of environment conditions for the ammonium phase distribution (solid/aqueous), which was solely aqueous at outside and almost entirely solid at inside tunnel. Regarding gaseous ammonia concentrations, the value measured inside the tunnel (46.5 ± 17.5 µg m(-3)) was 3-fold higher than that outside (15.2 ± 11.3 µg m(-3)). The NH3 vehicular emission factor (EF) estimated by carbon balance for urban tunnel was 44 ± 22 mg km(-1). From this EF value and considering the MASP traffic characteristics, it was possible to estimate more than 7 Gg NH3 year(-1) emissions that along with NOx are likely to cause rather serious problems to natural ecosystems in the region.

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Esta pesquisa foca a imagem profissional da Educação Física considerando a notoriedade que a mesma adquiriu na televisão ao longo dos últimos anos. O objetivo é explicitar alguns dos sentidos relacionados à abordagem da Educação Física escolar presentes na 18a temporada de Malhação, telenovela exibida pela Rede Globo. O método utilizado para nortear a investigação sobre o processo de produção de sentidos é a Análise do Discurso. Acerca dos resultados, evidenciamos que as situações de aula foram construídas com base em modalidades esportivas diferenciadas para meninos e meninas, privilegiando a técnica de execução dos gestos. Também foi marcante a dificuldade apresentada pelo professor ao lidar com questões que extrapolavam esta dimensão técnica. A abordagem midiática do profissional idoso no espaço escolar se configurou como novidade, porém, não permaneceu na temporada seguinte.

This research focuses on the professional image of physical education on TV series considering the reputation it has acquired over the past few years. The study aims at investigating some meanings given for Physical Education classes in the eighteenth season of "Malhação". The method used was Discourse Analysis. The results showed that the classes were built based on different sports for boys and girls, focusing on technical execution of the movements. Also, the difficulty of the teacher to deal with issues beyond technical approaches was noticed. The casting of an old man to play the role of a physical education teacher could be considered an interesting and original matter; however, it did not remain in the following seasons.

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Este ensaio apresenta algumas reflexões e análises acerca das danças descritas no livro Lavoura arcaica, de Raduan Nassar e no filme LavourArcaica, de Luiz Fernando Carvalho, tendo Rudolf Laban como um dos referenciais teóricos. Percebe-se que ao estabelecer um diálogo com Nassar, Carvalho faz em seu hipertexto fílmico uma (re)leituradas danças apresentadas em Lavoura arcaica, porém, em ambos os textos, temos a representação do Dabke, uma dança típica do folclore libanês.

This study presents some reflections and analysis concerning the dances described in Lavoura arcaica, a novel by Raduan Nassar, and LavourArcaica, a movie by Luiz Fernando Carvalho, presenting Rudolf Laban as one of the theoretical references. By establishing a dialog with Nassar, Carvalho does, in his filmic hypertext, a re(reading) of the dances presented in Lavoura arcaica, although we have in both the representation of Dabke, a typical folk dance from Lebanon.

Este estudio presenta algunas reflexiones y análisis sobre las danzas que se describen en El libro Lavoura arcaica, de Raduan Nassar, y em La película LavourArcaica, de Luiz Fernando Carvalho,teniendo Rudolf Laban como uno de los referentes teóricos. Mediante el establecimiento de un diálogo com Nassar, Carvalho hace en su hipertexto unare(lectura) de las danzas presentadas en Lavoura arcaica, aunque en ambos tenemos la representación del Dabke, una danza típica del folclore libanés.

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Este estudo propõe ref letir e analisar a representação das danças de Ana em Lavoura arcaica, obra literária de Raduan Nassar e fílmica de Luiz Fernando Carvalho, tendo como um dos principais referenciais teóricos Rudolf Von Laban. Foi possível concluir que na ausência de expressão verbal, Ana canaliza o seu desejo de comunicação em suas danças. Em sua primeira manifestação dançante exibe marcas da tradição e em sua segunda e última dança, os sinais da ruptura.

The aim of the present study was to analyse and reflect on the representations of Ana's dances in Lavoura arcaica, literary and filmic works of Raduan Nassar e Luiz Fernando de Carvalho, respectively, using as the main theoretical reference Rudolf Von Laban. It was possible to conclude that, in the absense of verbal expression, Ana channels her desire of communication into her dances. In her first dancing manifestation, she shows marks of tradition, and in her second and last dance, the signs of rupture.

Este estudio tiene como objetivo reflexionar y analizar la representación de danzas de Ana en Lavoura arcaica, obra literarias de Raduan Nassar, y cinematográfica de Luiz Fernando Carvalho, teniendo como uno de los principales teóricos Rudolf Von Laban. Se concluyó que, en ausencia de la expresión verbal, Ana canaliza su deseo de comunicarse a través de la danza. En su primera manifestación de baile enseña rasgos de la tradición, ya en la segunda y última danza, presenta los signos de ruptura.

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A Ioga é um sistema filosófico milenar originário da Índia, cujo objetivo principal é o desenvolvimento da união entre corpo e mente, através de exercícios, respiração e meditação, visando o bem-estar físico e mental. O estudo teve como objetivo avaliar os efeitos da prática regular de Hatha Ioga sobre a função ventilatória de mulheres saudáveis. Estudo transversal controlado, no qual participaram 25 mulheres, sendo os grupos IOGA e controle, compostos por 13 e 12 voluntárias, respectivamente. As voluntárias do grupo IOGA praticavam Hatha Ioga há pelo menos seis meses. A frequência respiratória foi avaliada através da contagem em um minuto; as pressões inspiratórias e expiratórias máximas foram avaliadas através da manovacuometria; as mobilidades torácicas axilar e xifóidea através da cirtometria; a capacidade vital forçada e o pico de fluxo expiratório através da espirometria. Foram encontradas diferenças significativas entre os grupos apenas com relação à frequência respiratória e mobilidade xifóidea. Pode-se concluir que a prática regular de Hatha Ioga mostrou-se capaz de influenciar positivamente a frequência respiratória e a mobilidade xifóidea.

Yoga is an ancient philosophic system that originated in India and whose main objective is the development of the union of mind and body through exercise, respiration and meditation. The objective of this study was to assess the effects of regular practice of Hatha Yoga on the respiratory function of healthy women. A controlled cross-sectional study was conducted on 25 female volunteers divided into two groups: Yoga (n=13) and control (n=12). The volunteers of the Yoga group had practiced Hatha Yoga for at least 6 months. The respiratory rate was counted over one minute. Maximal inspiratory and expiratory pressures were assessed with a manovacuometer. Axillary and xiphoid mobilities were assessed by cyrtometry. Chest expansion at the axillary and xiphoid levels was measured by cyrtometry. Forced vital capacity and peak expiratory flow were assessed by spirometry. Significant differences between groups were only observed for respiratory rate and xiphoid mobility. In conclusion, regular practice of Hatha Yoga had a positive impact on respiratory rate and xiphoid mobility in the population studied.

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This paper describes the automation of a fully electrochemical system for preconcentration, cleanup, separation and detection, comprising the hyphenation of a thin layer electrochemical flow cell with CE coupled with contactless conductivity detection (CE-C4D). Traces of heavy metal ions were extracted from the pulsed-flowing sample and accumulated on a glassy carbon working electrode by electroreduction for some minutes. Anodic stripping of the accumulated metals was synchronized with hydrodynamic injection into the capillary. The effect of the angle of the slant polished tip of the CE capillary and its orientation against the working electrode in the electrochemical preconcentration (EPC) flow cell and of the accumulation time were studied, aiming at maximum CE-C4D signal enhancement. After 6 min of EPC, enhancement factors close to 50 times were obtained for thallium, lead, cadmium and copper ions, and about 16 for zinc ions. Limits of detection below 25 nmol/L were estimated for all target analytes but zinc. A second separation dimension was added to the CE separation capabilities by staircase scanning of the potentiostatic deposition and/or stripping potentials of metal ions, as implemented with the EPC-CE-C4D flow system. A matrix exchange between the deposition and stripping steps, highly valuable for sample cleanup, can be straightforwardly programmed with the multi-pumping flow management system. The automated simultaneous determination of the traces of five accumulable heavy metals together with four non-accumulated alkaline and alkaline earth metals in a single run was demonstrated, to highlight the potentiality of the system.

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O objetivo do presente estudo foi avaliar, em um grupo de mulheres saudáveis, os efeitos da prática regular de Ioga sobre a qualidade de vida. Tratou-se de um estudo transversal controlado, no qual participaram 25 mulheres saudáveis, com idades entre 20 e 59 anos, divididas nos grupos IOGA (praticantes há pelo menos seis meses) e CONTROLE (sedentárias), compostos respectivamente por 13 e 12 voluntárias. A qualidade de vida foi avaliada utilizando-se o questionário SF-36. Para análise estatística foram realizados o teste t independente e as provas não paramétricas de Mann-Whitney. O grupo IOGA apresentou pontuação significativamente mais elevada no domínio “dor” e no escore físico geral (p < 0,05) do questionário SF-36. Concluímos que, na população avaliada, a prática regular de Hatha Ioga demonstrou ser capaz de influenciar positivamente determinados aspectos da qualidade de vida.

The aim of the present study was to evaluate, in a group of healthy women, whether the regular practice of Hatha Yoga could have an impact on their quality of life. It was a transversal controlled study, composed by 25 women, aged between 20 and 59 years, divided in two groups: YOGA (at least six months of Hatha Yoga practice) and CONTROL (non-active women), composed by 13 and 12 volunteers, respectively. The quality of life was assessed through the SF-36 questionnaire. The statistical procedures included the independent t test and the Mann-Whitney tests. The YOGA group presented higher scores in the “body pain” domain and in the general physical score (p < 0,05). It can be concluded that, in the assessed population, the regular practice of Hatha Yoga has positively influenced some aspects of the quality of life.

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The analytical determination of atmospheric pollutants still presents challenges due to the low-level concentrations (frequently in the µg m(-3) range) and their variations with sampling site and time. In this work, a capillary membrane diffusion scrubber (CMDS) was scaled down to match with capillary electrophoresis (CE), a quick separation technique that requires nothing more than some nanoliters of sample and, when combined with capacitively coupled contactless conductometric detection (C(4)D), is particularly favorable for ionic species that do not absorb in the UV-vis region, like the target analytes formaldehyde, formic acid, acetic acid and ammonium. The CMDS was coaxially assembled inside a PTFE tube and fed with acceptor phase (deionized water for species with a high Henry's constant such as formaldehyde and carboxylic acids, or acidic solution for ammonia sampling with equilibrium displacement to the non-volatile ammonium ion) at a low flow rate (8.3 nL s(-1)), while the sample was aspirated through the annular gap of the concentric tubes at 2.5 mL s(-1). A second unit, in all similar to the CMDS, was operated as a capillary membrane diffusion emitter (CMDE), generating a gas flow with know concentrations of ammonia for the evaluation of the CMDS. The fluids of the system were driven with inexpensive aquarium air pumps, and the collected samples were stored in vials cooled by a Peltier element. Complete protocols were developed for the analysis, in air, of NH(3), CH(3)COOH, HCOOH and, with a derivatization setup, CH(2)O, by associating the CMDS collection with the determination by CE-C(4)D. The ammonia concentrations obtained by electrophoresis were checked against the reference spectrophotometric method based on Berthelot's reaction. Sensitivity enhancements of this reference method were achieved by using a modified Berthelot reaction, solenoid micro-pumps for liquid propulsion and a long optical path cell based on a liquid core waveguide (LCW). All techniques and methods of this work are in line with the green analytical chemistry trends.

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Compared to other volatile carbonylic compounds present in outdoor air, formaldehyde (CH(2)O) is the most toxic, deserving more attention in terms of indoor and outdoor air quality legislation and control. The analytical determination of CH(2)O in air still presents challenges due to the low-level concentration (in the sub-ppb range) and its variation with sampling site and time. Of the many available analytical methods for carbonylic compounds, the most widespread one is the time consuming collection in cartridges impregnated with 2,4-dinitrophenylhydrazine followed by the analysis of the formed hydrazones by HPLC. The present work proposes the use of polypropylene hollow porous capillary fibers to achieve efficient CH(2)O collection. The Oxyphan fiber (designed for blood oxygenation) was chosen for this purpose because it presents good mechanical resistance, high density of very fine pores and high ratio of collection area to volume of the acceptor fluid in the tube, all favorable for the development of air sampling apparatus. The collector device consists of a Teflon pipe inside of which a bundle of polypropylene microporous capillary membranes was introduced. While the acceptor passes at a low flow rate through the capillaries, the sampled air circulates around the fibers, impelled by a low flow membrane pump (of the type used for aquariums ventilation). The coupling of this sampling technique with the selective and quantitative determination of CH(2)O, in the form of hydroxymethanesulfonate (HMS) after derivatization with HSO(3)(-), by capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C(4)D) enabled the development of a complete analytical protocol for the CH(2)O evaluation in air.

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