Abstract A study on aerosols in the Brazilian subequatorial Amazon region, Tangará da Serra (TS) and Alta Floresta (AF) was conducted and compared to findings in an additional site with background characteristics (Manaus, AM). TS and AF counties suffer from intense biomass burning periods in the dry season, and it accounts for high levels of particles in the atmosphere. Chemical characterization of fine and coarse particulate matter (PM) was performed to quantify water-soluble ions (WSI) and black carbon (BC). The importance of explanatory variables was assessed using three machine learning techniques. Average concentrations of PM in AF and TS were similar (PM2.0, 17±10 µg m-3 (AF) and 16±11 µg m-3 (TS) and PM10-2.0, 13±5 µg m-3 (AF) and 11±7 µg m-3 (TS)), but higher than the background site. BC and SO4 2- were the prevalent components as they represented 27%–68% of particulates chemical composition. The combination of the machine learning techniques provided a further understanding of the pathways for PM concentration variability, and the results highlighted the influence of biomass burning for key sample groups and periods. PM2.0, BC, and most WSI presented higher concentrations in the dry season, providing further support for the influence of biomass burning.

Sepetiba Bay, Rio de Janeiro, Brazil, was home to a zinc smelter until its shutdown in 1998, and during 2011 the remains of the smelter were decommissioned. This study investigates the impact of decommissioning on metal concentrations in the bottom sediments of the bay. In addition to Zn and Cd, Cr, Cu, Ni and Pb are also quantified. The results show that over these 15 years, Cd and Zn concentrations have decreased by 100 and 70%, respectively. Temporal effects are also studied by applying five dated 210Pb cores, which are validated using the Zn and Cd profiles. The observed decrease in the Zn concentration in oysters is correlated with its reduction in the sediment. It was possible to verify the impact of Cr, Cu, Ni and Pb on the sediment quality due to the remaining metallurgical industries in the Sepetiba Bay basin.

During the period from June 2012 to June 2013, the concentrations and chemical composition of PM2.5 and PM2.5-10 (particulate matter with a diameter of 2.5 μm or less and between 2.5 and 10 μm, respectively) were monitored at four sampling points in the Rio de Janeiro metropolitan area, and two of the points were in close proximity to the 2016 Olympic Games facilities with a total of 122 samples at each sampling point. At all four sampling stations, the annual mean value of PM10 was above the World Health Organization (WHO) air quality guideline, although frequent violations of the 24 h guideline were observed at only two of the points, Duque de Caxias and Taquara. On the other hand, PM2.5 concentrations at the four sampling points met both the annual and 24 h WHO PM2.5 air quality guidelines. The vehicular contribution to PM2.5 ranged from 48 to 70%, with a mean value of 59 ± 9%. Considering that the Brazilian market already has fuel quality that is comparable to international standards (gasoline S50 and diesel S10), further air quality improvements are expected with investments in a public transport network, urban mobility programs and fleet renewal, which are considered a legacy of the 2016 Olympic Games.

For the first time, the boron isotopic ratio is reported for Brazilian red wines. The boron concentration, 11B/10B isotopic ratio and δ11B were determined in 89 red wines produced in Campanha Gaúcha, Serra Gaúcha (SG), and Vale dos Vinhedos (VV) in South Brazil and Vale do São Francisco (VSF) in Northeast Brazil. A broad boron concentration range, < 0.07 to 20.4 mg L-1, was observed, where a few values were above the maximum allowed concentration according to the International Code of Oenological Practices (14.0 mg L-1). The obtained 11B/10B ratios were quite different from those observed in the literature. The ratios were quite similar among the Southern Brazilian wine producing areas, but a large difference was observed when compared with the Northeastern wines, allowing for the differentiation between these two important Brazilian wine regions. The results have also shown that is possible, based on the boron isotopic ratio, to differentiate the Brazilian red wines from Chilean, Italian and Portuguese red wine.

Este estudo é uma avaliação das taxas de sedimentação na região do delta do Rio Paraíba do Sul e sua correlação com a forte erosão que ocorre em Atafona, Rio de Janeiro. Os resultados obtidos são baseados 14 testemunhos de sedimentos, com um total de aproximadamente 540 amostras, coletados em janeiro de 2010 e fevereiro de 2011. Os inventários de 210Pb nos pontos de amostragem ao sul da desembocadura do Rio Paraíba do Sul foram maiores do que aqueles observados para os pontos de coleta na região norte e central, o que sugere que os sedimentos são transportados ao longo da costa com as correntes nesta direção. Os resultados da datação 210Pb foram validados com base na variação de concentração elementar ao longo de dois dos testemunhos. Concentrações de Cd e Zn aumentaram significativamente em 1982 e atingindo valores máximos (0,5 mg kg-1 e 139 mg kg-1, respectivamente) em 1984. Estes máximos correspondem ao acidente da indústria Cia Paraibuna de Metais, que ocorreu em 1982.

This study aims to evaluate sedimentation rates in the Paraíba do Sul estuary and its shelf regions. These sedimentation rates were correlated with strong erosion occurring in Atafona, Rio de Janeiro. The results were based on four transects, from which 14 sediment cores with approximately 540 sediment samples were collected in January 2010 and February 2011. At sampling points south of the Paraíba do Sul River (PSR) mouth, 210Pb inventories were higher than those at the northern and central sampling locations, suggesting that sediment is transported southward by the alongshore current. The 210Pb dating results were validated based on the elemental concentration variation throughout two of the sediment cores. Heavy metal concentrations, such as Cd and Zn, increased significantly in 1982 and reached maximum values (0.5 mg kg-1 and 139 mg kg-1, respectively) in 1984. These maxima correspond to the Cia Paraibuna de Metais industry accident, which occurred in 1982.

Foi desenvolvido um método para determinação de 234U e 230Th empregando uma separação por extração cromatográfica seguida por medidas com ICP-MS quadrupolar (ICP-QMS). Para carbonatos autigênicos, uma segunda etapa de separação, por cromatografia de troca-iônica em meio nítrico, foi incluída. Esses métodos foram aplicados a sete amostras de fósseis de corais de águas profundas e duas amostras de carbonato autigênicos do talude continental da Bacia de Campos. As idades determinadas para as amostras de fósseis de corais variaram entre 9-202 kanos com uma incerteza de 1%, consistente com os valores determinados pela datação com 14C, bem como com as idades 230Th/234U determinadas por FIAS-ICP-QMS. Uma das amostras de carbonato autigênico analisada apresentou uma idade de aproximadamente 80 kanos. A outra amostra apresentou uma razão 230Th/234U próximo do equilíbrio e fora da faixa de aplicação do método.

A 234U and 230Th determination method based on an extraction chromatographic separation followed by ICP-MS with quadrupole (ICP-QMS) was developed. For authigenic carbonates, a second separation step with ion exchange chromatography in a HNO3 solution was added. These methods were applied to seven fossil deep-water coral and two authigenic carbonate samples from the continental slope of the Campos Basin - Brazil. The ages determined for the fossil corals samples from the same sediment core ranged from 9 to 202 ky with a 1% uncertainty, consistent with the values determined by 14C dating and with those determined by 230Th/234U using flow injection coupled to an ICP-QMS. One of the authigenic carbonates analyzed presented an age of approximately 80 ky. The other sample exhibited a 230Th/234U activity ratio close to equilibrium and out of the application range of the method.

Resumo: Para resgatar os episódios vividos por Charles Darwin no estado do Rio de Janeiro e que fizeram parte da sua formação científica a bordo do Beagle, está em execução o Projeto Caminhos de Darwin. Em sua vertente geológica, estão sendo descritos, para fins de geoconservação, os afloramentos por ele descritos. O beachrock de Jaconé foi identificado pelo naturalista, então com 23 anos de idade, em 9 de abril de 1832. Com o passar dos anos e com pesquisas arqueológicas realizadas na região foram descobertos seixos de beachrock nos sambaquis da Beirada e de Moa, em Saquarema, mostrando que este material já era conhecido do homem pré-histórico há mais de 4000 anos A.P. No presente estudo, buscou-se realizar o enquadramento destas exposições como patrimônio geológico e, ao mesmo tempo, atualizar o conhecimento sobre sua geologia. Foram identificadas 3 litofácies e duas delas foram analisadas petrograficamente. Suas conchas foram datadas em 8198 - 7827 cal BP, pelo método radiocarbono. Concluiu-se que é inegável seu valor e que se constitui em patrimônio geológico, seja por sua importância histórica e cultural, seja pelas informações geológicas que pôde fornecer. A ocorrência se constitui como patrimônio geológico do tipo geomorfológico, sedimentar, paleoambiental, petrológico, além de arqueológico e contextualizado na história da ciência. Tem importância internacional e valor científico, cultural, didático e ecológico.

Abstract: The Caminhos de Darwin Project aims to redeem the episodes experienced by Charles Darwin in the state of Rio de Janeiro and that they have had part in his scientific training aboard the Beagle. In the geological approach of this project, the outcrops described by Darwin in the State of Rio de Janeiro are being described with purposes of geoconservation. The beachrock of Jaconé was identified by the naturalist, at then 23 years old, on April 9, 1832. Over the years, archaeological researches conducted in the region discovered pebbles of beachrock in the middens of Beirada and Moa. This fact demonstrates that thisrock was already known by prehistoric men for over 4000 years BP. The present study aimed to assess these outcrops as geological heritage and, at the same time, update the knowledge about its geology. Three lithofacies were identified and two of them were analyzed petrographically. The age of the shells was calculated at 8198-7827 cal BP by the radiocarbon method. The occurrence is constituted as a geological heritage of the following typologies: geomorphological, sedimentary, paleoenvironmental, petrological, and archaeological and, also, contextualized in the science history. It has international significance and scientific, cultural, educational and ecological value.

Foi realizada a amostragem de aerossol em dez locais distribuídos em diferentes regiões da cidade do Rio de Janeiro, de setembro/2003 a setembro/2004, em uma base semanal com amostragens de 24 horas. As frações do aerossol PM2.5 e PM2.5-10 foram amostradas usando um sistema com filtros em série. Foram determinadas: a massa do aerossol, carbono elementar, a concentração dos íons solúveis, assim como a concentração total de alumínio, cálcio, ferro, magnésio, potássio, sódio e titânio. A concentração mássica média anual do PM10 variou de 18 a 38 mg m-3, sem violação dos padrões brasileiros de qualidade do ar. Para as frações fina e grossa, entre 70 e 90% da massa medida foi identificada como sendo devido à poucas fontes, sendo que a poeira do solo explica 37-63% da massa da fração grossa (PM2.5-10). Por outro lado, o carbono elementar e o aerossol secundário representam proporções elevadas (45-58%) da massa da fração fina (PM2.5).

Aerosol sampling was performed at ten sites distributed in different location of Rio de Janeiro city, from September/2003 to Sepetember/2004, on a weekly basis with 24 h sampling time interval. PM2.5 and PM2.5-10 aerosol particles were sampled using Stacked Filter Units (SFU). Aerosol mass, black carbon, water soluble ions concentration as well as total aluminum, calcium, iron, magnesium, potassium, sodium and titanium concentration were determined. Mean annual PM10 mass concentration ranged from 18 to 38 µg m-3, without violation of the Brazilian air quality standards. For fine and coarse modes, between 70 and 90% of the measured mass was apportioned to relatively few sources, soil dust accounts for 37-63% of the coarse mode mass. On the other hand, black carbon and secondary aerosol, related to anthropogenic sources as fuel burning, represents very high proportions (45-58%) of the PM2.5 mass.

A fim de avaliar a aplicabilidade da espectrometria de massa com plasma indutivamente acoplado à determinação de idades Pb/Pb, U/Pb e Th/Pb de monazitas, estudos foram realizados, inicialmente, em padrões isotópicos de referência para chumbo (NIST SRM 981 e 982). Posteriormente, a metodologia otimizada foi aplicada a areias monazíticas de três diferentes locais, Pão de Açúcar (Rio de Janeiro), Buena (Estado do Rio de Janeiro) e Praia Negra (Guarapari, Estado do Espirito Santo); as idades médias obtidas, (581 ± 21)Ma, (552 ± 32)Ma e (535 ± 3)Ma, respectivamente, estão de acordo com os valores da literatura para amostras de zircão e de monazita dos mesmos locais. Idades Th/Pb com mono-grãos foram também determinadas para a amostra de monazita da Praia Negra, nove grãos foram analisados e o valor médio, (530 ± 26)Ma, está no acordo com o valor obtido com alíquotas maiores. Finalmente, o método foi aplicado a uma amostra do torianita do Estado de Amapá e as idades obtidas Th-Pb, U-Pb e Pb-Pb foram de (2,15 ± 0,05)Ga, (2,03 ± 0,01)Ga e (2,044 ± 0,006)Ga, respectivamente, com um valor médio de (2,08 ± 0,07)Ga, coerente com a idade de (2,08 ± 0,02)Ga do complexo de Bacuri, Amapá, relatada na literatura.

In order to evaluate the applicability of inductively coupled plasma quadrupole mass spectrometry to the determination of Pb/Pb, U/Pb and Th/Pb ages of monazite, studies were carried out initially applying lead atom ratio reference standards (NIST SRM 981 and 982). Further, the optimized methodology was applied to monazite sands from three different sites, Sugar Loaf Hill (Rio de Janeiro city), Buena (Rio de Janeiro state) and Black Sands Beach (Guarapari, Espirito Santo state); the obtained mean ages, (581 ± 21)Myears, (552 ± 32)Myears and (535 ± 3)Myears, respectively, are in agreement with the literature values for zircon and monazite samples from the same sites. Single grain Th/Pb ages were also determined for the monazite sample from Black Sands beach, nine grains were analyzed and the mean value, (530 ± 26)Myears, is in agreement with the value obtained with bulk samples. Finally, the method was applied to a thorianite sample from Amapá state and the observed Th-Pb, U-Pb and Pb-Pb ages obtained were (2.15 ± 0.05)Gyears, (2.03 ± 0.01)Gyears anda (2.044 ± 0.006)Gyears respectively, with a mean value of (2.08 ± 0.07)Gyears. This value is coherent with the (2.08 ± 0.02)Gyears age of the Bacuri complex, Amapá, reported in the literature.

O presente trabalho apresenta os resultados de 226Ra e 228Ra obtidos durante o 4º experimento de intercomparação referente à descarga submarina de água subterrânea (Submarine Groundwater Discharge, SGD) realizado em Ubatuba (SP), em novembro/2003. Este experimento visava testar, em um sistema de rochas cristalinas fraturadas, as diferentes metodologias existentes de determinação da SDG. Embora com objetivo distinto, decidiu-se participar deste experimento de modo a verificar se os isótopos de rádio poderiam ser empregados no estudo de mistura de águas na região e, também, testar a capacidade analítica do laboratório, visando uma futura validação de modelos de dispersão marinha para o local de instalação dos reatores nucleares de Angra dos Reis, distantes apenas setenta quilômetros da região do experimento. Além das concentrações de 228Ra e 226Ra, resultados de salinidade, bário e sílica também são apresentados e suas relações com a concentração de 228Ra são discutidas.

The present work reports 228Ra and 226Ra results obtained during the 4th Submarine Groundwater Discharge (SGD) intercomparison experiment realized in Ubatuba, November 2003, aiming to test the methodologies on a fractured crystalline rocks system. Although with distinct objectives, it was decided to participate in this experiment in order to verify if radium isotopes could be used to determine water mixing rates in this region and to test the laboratory capability to perform, later on, a marine dispersion model validation at Angra dos Reis reactor site, located nearby. The results show that the SGD model constrains seems to be valid, at least for a distance of 20 km offshore, that corresponds to the distance between the reactor site and Ilha Grande, a 193-km² island existing at this site and probably an additional SGD source. Salinity, barium and silica results are also reported and their relation to 228Ra concentrations is discussed.

The sambaquis are archaeological sites with remains of pre-historical Brazilian civilizations. They look like small hills containing different kinds of shells, animal and fish bones, small artifacts and even human skeletons. Since the sambaqui sites in the Rio de Janeiro state are younger than 6000 years, the applicability of CO2 absorption on Carbo-Sorb® and 14C determination by counting on a low background liquid scintillation counter was tested. The International Atomic Energy Agency standard reference material IAEA-C2 was used in order to standardize the method. Nine sambaqui samples from five different archaeological sites found in the Rio de Janeiro state were analyzed and 14C ages between 2100 and 3600 years BP were observed. The same samples were sent to the 14C Laboratory of the Centro de Energia Nuclear na Agricultura (CENA/USP) where similar results were obtained.