Uranium and radium are present in soil, rocks, water and building materials, therefore the presence of 222Rn in the air is natural, and its concentration is determined mainly by physical factors such as soil cover, altitude, porosity and soil particle size, and meteorological conditions. In rooms with poor ventilation,222Rn can accumulate to high concentrations, which increases the risk of developing lung cancer due to continuous exposure to this gas. In this work,222Rn was monitored, with the aid of a real-time radon monitor, RAD7, in offices and rooms at Hospital Universitário Antônio Pedro in order to evaluate the levels of 222Rn to which people are exposed. In general, the values measured in this work are similar to values observed in other studies around the world. The obtained 222Rn level of 40 Bq m-3 is close to the world average of 37 Bq m-3 defined by the United States Environmental Protection Agency (US EPA).

The atmospheric deposition of dissolved trace elements was investigated in two subtropical estuarine systems, located on the coast of Paraná, Southeast Brazil. The samples (n = 91) were collected in three periods, from May to September 2010, in four different areas. Trace elements concentrations (Al, Fe, Zn, Mn, Ba, Ca, Mo, V, As, Cu, Co, Ni, Cr and Pb) were determined for dissolved fraction using inductively coupled plasma-mass spectrometry (ICP-MS). pH measurements revealed the occurrence of a slightly acidic precipitation in the investigated points. Among the trace elements, Zn was the most abundant, followed by Al, Fe, Mn, Cu, Ba and V. The analysis of the enrichment factors enabled the identification of the different sources of the analysed elements. The origin of the Al and Fe elements were entirely continental, whereas Zn was primarily associated with human activities. Thus, the atmospheric deposition may be a primary route of exposure to anthropogenic Zn for estuarine biota.

Nós investigamos o papel do plâncton no ciclo do vanádio (V) em Cabo Frio, Rio de Janeiro, Brasil, uma região com alta concentração de V nas partículas atmosféricas, devido ao aerossol marinho. As concentrações de V no plâncton variaram de 0,08-20,9 µg g-1 (zooplâncton), 0,1-28,4 µg g-1 (fitoplâncton > 64 µm) e < 0,0005-49,0 µg g¹ (pequeno fitoplâncton > 20 µm). A especiação de V associado a biomoléculas foi realizada por duas estratégias: (i) o acoplamento de cromatografia de exclusão de tamanho (SEC) para o fracionamento de espécies com espectrometria de massas com plasma indutivamente acoplado (ICP-MS) e (ii) cromatografia de exclusão de tamanho por troca aniônica com detector UV-Vis acoplado a espectrometria de massas com plasma indutivamente acoplado (SEC-AE-UV-Vis-ICP-MS). Os resultados mostraram uma única fração contendo V associada a uma biomolécula na faixa de 8 a 16 kDa, com ponto isoelétrico acima de 8. Resultados preliminares usando MALDI-TOF não permitem identificar a biomolécula, considerando a larga faixa de massa molecular obtida.

We investigated the role of plankton in the vanadium (V) cycle at Cabo Frio, Rio de Janeiro state, Brazil, a region with high V concentration in the atmospheric particles due to marine aerosol. The concentrations of V in plankton vary from 0.08 to 20.9 µg g-1 (zooplankton), 0.1 to 28.4 µg g-1 (phytoplankton > 64 µm) and < 0.0005 to 49.0 µg g-1 (small phytoplankton > 20 µm). The V speciation in biomolecules was performed by the use of two strategies: (i) coupling of size exclusion chromatography (SEC) for the fractionation of species with inductively coupled plasma mass spectrometry (ICP-MS) and (ii) with size exclusion anionic exchange chromatography with UV-Vis detector coupled to inductively coupled plasma mass spectrometry (SEC-AE-UV-Vis-ICP-MS). The results showed a single fraction containing V associated with a biomolecule in the range of 8 to 16 kDa, with isoeletric points above 8. The preliminary analyses using matrix-assisted laser desorption-ionization-time of flight (MALDI-TOF) do not permit to identify such biomolecule, considering the broader size range of the proteins obtained.

As concentrações dos elementos maiores (Na+, Ca2+, Mg2+, K+, Cl-, SO4(2-)) foram analisadas na água intersticial de poços piezométricos localizados em diferentes fácies geobotânicas ao longo de um transecto num ecossistema de manguezal na Baía de Sepetiba - Rio de Janeiro. Maiores salinidades e concentrações dos íons maiores são evidencias de evapotranspiração no fácies apicum. Ainda no apicum foram observados os maiores desvios padrão da razão elemento/Cl− durante o período do estudo, indicando intensa diagênese in situ. Razões molares no piezômetro, localizado na borda do manguezal foram consideravelmente menores do que a fonte de água doce, indicando forte influência do fluxo de água marinha. Os resultados das razões molares, SO4(2-)/Cl− e Ca2+/Cl− na borda do manguezal adjacente ao continente sugerem limitada redução de SO4(2-) enquanto os valores relativamente altos na razão Ca2+/Cl− indicam contacto recente com água marinha.

Concentrations of cations and anions of major elements (Na+, Ca2+, Mg2+, K+, Cl-, SO4 2-) were analyzed in the pore water of a mangrove habitat. Site specific major element concentrations were identified along a four piezometric well transect, which were placed in distinct geobotanic facies. Evapotranspiration was evident in the apicum station, given the high salinity and major element concentrations. The station landward of an apicum was where major element/Cl- ratios standard deviations are greatest, suggesting intense in situ diagenesis. Molar ratios in the most continental station (4) are significantly lower than the nearby freshwater source, indicating a strong influence of sea water flux into the outer reaches of the mangrove ecosystem and encroaching on the Atlantic rain forest. Indeed, the SO4 2-/Cl- and Ca2+/Cl- ratios suggest limited SO4 2- reduction and relatively high Ca2+/Cl- ratios indicate a region of recent saltwater contact.

The aim of this review is to take a look at Cold War era nuclear tests signatures found in Brazilian coastal sediments. Both137Cs and 240+239Pu signatures have been documented in mangrove, coastal mudflats and continental shelf sediments, associated with above ground nuclear tests beginning in the 1950's. The dates associated to the anthropogenic radionuclide signatures 137Cs and 240+239Pu along sediment columns are confirmed by 210Pb geochronology in many of the studies highlighted in this review. The results outlined in this review characterize the extent to which nuclear fallout products reach the Brazilian coast in quantities sufficient for detection, allowing the use of these radioisotopes as geochronometers.

O sítio industrial abandonado na Baía de Sepetiba (SE-Brasil) está entre os maiores passivos ambientais contaminados com Zn no mundo e o As também se encontra em concentrações alarmantes. A vegetação no local é escassa e das espécies que sobrevivem no local Pityrogramma calomelanos e Nephrolepis biserrata são as mais abundantes. Concentrações de As de até 2271 mg kg-1 foram detectadas na espécie Pityrogramma calomelanos, sendo que essa espécie foi mais eficiente que N. Bisserata no acúmulo desse elemento. Utilizou-se cromatografia de exclusão por tamanho (SEC) com detecção UV-Vis e espectrometria de massas com plasma indutivamente acoplado (ICP-MS) em sistema "on line" para monitorar a distribuição de As na fração orgânica. As maiores concentrações de As foram determinadas na fração extraída com TRIS-HCl, pH 7,4 (entre 60-100% da concentração total de As) mostrando uma evidente associação desse elemento com bioligantes, entre eles, fitoquelatinas e glutationa.

The abandoned industrial site at the Sepetiba Bay (SE-Brazil) is one of the most heavily contaminated sites on the earth's surface concerned to Zn, but also presents As in alarming concentrations. Vegetation on this site is scarce and under the surviving species Pityrogramma calomelanos and Nephrolepis biserrata are the most abundant ones. Total As concentrations up to 2271 mg kg-1 in P. calomelanos were determined, being this specie more efficient in arsenic accumulation than N. bisserata. The size exclusion chromatography (SEC) with UV-Vis detector coupled to inductively coupled plasma mass spectrometry (ICP-MS) was used to screen the distribution of As between different molar mass fractions. Highest concentration of As was found after extraction with TRIS-HCl, pH 7.4 (about 60-100% of total As) characterizing an association of this element with bioligands including phytochelatins and glutathione.

O estudo de metais em áreas preservadas assume grande relevância devido à falta de níveis de base para comparação com estudos em áreas impactadas. Para 23 amostras de sedimento de superfície da Baía da Ribeira, RJ, foram determinadas por ICP/AES as concentrações de Ti, Ca, Mg, Fe, Al, Sr, La, V, Y, Ni, Cu, Cr, Mn e Zn. Hg foi determinado por CVAAS. Utilizando Al como referência, os metais foram classificados como associados, intermediários, inversamente associados e não associados a Al. A análise de agrupamento dos dados confirmou esta classificação, exceto para o Hg. A análise de agrupamento dos locais amostrados gerou 3 grupos, controlados por granulação, influência continental e influência marinha. Fatores climáticos e hidrodinâmicos, além das características dos solos, são importantes na distribuição dos metais. A área apresenta níveis naturais de metais, comparáveis a folhelhos médios e a outras áreas impactadas e não impactadas.

Investigation of metal distribution in preserved areas is highly relevant due to the present-day lack of reliable databases against which to assess contamination. 23 samples of surface sediments from the Ribeira Bay, Rio de Janeiro State, Brazil, were analyzed by ICP/AES for Ti, Ca, Mg, Fe, Al, Sr, La, V, Y, Ni, Cu, Cr, Mn and Zn. Hg concentrations were determined by CVAAS. With respect to Al, metals were classified as strongly correlated, correlated, inversely correlated and non-correlated. Cluster analysis of the concentration data confirmed this, except for Hg. Cluster analysis of the sampling sites produced three groups, on the basis of grainsize, continental input, and marine input. Climatic and hydrodynamic factors, as well as soil characteristics, are important controls of the metal distribution in this region. The Ribeira Bay has a natural background metal content, when compared with average shales and with other impacted and non-impacted regions.