Abstract Activities related to the marine exploration of oil and gas reservoirs tend to cause a concentration of natural radionuclides in related materials. As such, knowledge regarding the distribution of radionuclides in sedimentary basins with current oil operations is essential for modeling radiological hazards and possible risks of site contamination. This study investigated the distribution of 226Ra and 228Ra, radioisotopes from the 232U and 232Th decay chains in bottom sediment of the Santos basin. Sediment samples were collected from sites in a sampling grid based on depth contours and were analyzed through high-resolution gamma spectrometry. A distribution model of the spatial variation of these isotopes, the frst of its kind for the Basin, supported the interpretation of similar tendencies in their distribution. From studying the spatial trends of the mean levels of the isotopes with descriptive statistics and variance analysis, latitudinal and bathymetric diferences in the content of radionuclides emerged. These diferences are probably derived from the distinct sources of these elements, as 226Ra originates in the deep ocean from the decay of parent 230Th and from the patterns of sedimentation driven by open ocean circulation, while 228Ra is supplied by terrigenous materials transported by the northward-fowing Brazilian Coastal Current. such contamination Ra U Th basin highresolution high resolution spectrometry Basin analysis emerged elements circulation northwardfowing northward fowing Current

Abstract Carbonate mounds and pockmarks are geologically and ecologically important features distributed worldwide in the world’s oceans. In the present study, we present a chemical characterization of deep-sea scleractinian coral skeletons collected in these geomorphological areas at the southeastern continental margin of Brazil. Coral samples were collected from ten sampling stations during cruises aboard the R/V Alpha Crucis, in 2019. Three species of scleractinian corals were studied: Enallopsammia rostrata, Solenosmilia variabilis, and Desmophyllum pertusum. Stable isotopes of carbon and oxygen (δ13C and δ18O), metals, and phosphorus present in the coral carbonate skeletons were analyzed. Corals are recognized as archives of physical-chemical variations in the marine environment, and the Element/Ca ratios, δ13C, and δ18O allowed for the characterization of the studied areas. Chemical composition found in pockmark areas indicated affinity to terrigenous and particulate materials input (Ba/Ca, Fe/Ca, Mn/Ca, Li/Ca, and Mg/Ca). Greater availability of nutrients and anthropogenic materials (Pb/Ca, Cd/Ca, Zn/Ca, and P/Ca) is also likely to occur in this region, with some elemental ratios higher than those measured in other oceans. These mounds can act as barriers for metals from land flows. Also, corals benefit from a higher food supply due to stronger currents. The corals at the top of the Alpha Crucis Carbonate Ridge receive significant marine influence. Most coral samples have carbonate of aragonitic origin, except for a specimen of D. pertusum, which presented carbonate of biogenic calcite and aragonite. The results demonstrate the potential of scleractinian corals in the chemical characterization of the deep ocean and the need for further investigation of carbonate mound areas from the SW Atlantic.

Abstract Although carbonate mounds have been investigated for 100 years, few studies focus on the giant variety. The Alpha Crucis Carbonate Ridge (ACCR), a ~17 x 12-km ring-shaped ridge formed by hundreds of mounded structures, located between the 300 and 800-m isobaths and reaching a maximum height of 340 meters above the adjacent seafloor, is the first giant carbonate mounded feature described for the SW Atlantic margin. This study provides the first multiproxy approach to investigate sediments covering the ACCR and its adjacencies. Most of the area is located under the Intermediate Western Boundary Current (IWBC) flow, which carries the nutrient-rich Antarctic Intermediate Water (AAIW). Radiocarbon aging shows pronounced differences for the shallow layers (MIS3 for the top of the mounds and late Holocene for the adjacencies). Grain size data indicate the prevalence of sandy fractions on top of the mounds and muddy sediments in the adjacent areas. Fe/Ca and Ti/Ca proxies allowed for identifying mainly biogenic sedimentation in the area. However, the input of allochthonous terrigenous sediment is necessary for mound buildup, and values of Fe and Ti collected on the top of the mounds are significant. End-Members distributions and metal concentrations also allowed for recognition of distinct sources of sediment. εNd and Ln(Fe/K) indicated two primary terrigenous sources, the Precambrian rocks of the Brazilian shield (Cabo Frio end-member) and the multiple lithologies drained by the Rio de la Plata basin. Redox condition proxies indicated that the area is submitted to oxic conditions, probably reflecting the action of the IWBC. This work provides the first insight into an integrated grain-size and geochemical characterization of the Alpha Crucis Carbonate Ridge (southwestern Atlantic margin).

RESUMO: Neste artigo, apresentamos novas evidências sobre a transgressão ocorrida Estágio Isotópico 3 (MIS3) na costa do sudeste do Brasil (Baixada Santista). Dados coletados por meio de um ensaio de penetração em solo (SPT) revelam a ocorrência de sedimentos mixohalinos entre 45.000 e 41.000 anos a.P. Uma sequência mais profunda, que mostra clara transição de ambiente continental para um mixohalino, foi associada ao Estágio Isotópico 5e (MIS5e). Marcadores orgânicos e inorgânicos foram usados para reconhecer as variações dos ambientes terrestre/mixohalino/marinho, bem como inferir sobre o clima e a energia do ambiente deposicional. Uma mudança ambiental, que poderia corresponder a um pico do nível do mar ou à ocorrência de condições mais secas, foi reconhecida entre 43.000 e 42.000 anos a.P. Os resultados reforçam a necessidade de futuros trabalhos sobre a variabilidade do MIS3 na costa atlântica sul-americana.

ABSTRACT: In this paper, we present new evidence regarding a Marine Isotope Stage 3 (MIS3) transgression on the south-eastern Brazilian coast (Baixada Santista coastal plain). Data collected from a Standard Penetration Test (SPT) drilling reveal the occurrence of myxohaline sediments between cal BP 45,000 and 41,000. A deeper sequence, which shows a clear transition from terrestrial to a myxohaline environment, was associated with MIS5e. Organic and inorganic proxies have been used to recognize the variations on the terrestrial/myxohaline/marine deposits, as well as to infer about climate and energy of the depositional environment. Environmental change, which could correspond to a sea-level peak or the occurrence of drier conditions, was recognized between 43,000 and 42,000 cal BP. The results reinforce the need for future works on MIS3 variability on the South American Atlantic coast.

Este estudo apresenta uma avaliação da deposição de elementos potencialmente tóxicos no Canal de Bertioga (costa sudeste brasileira) ao longo de 150 anos, período principal de atividade antropogênica na área. O trabalho analisou cinco testemunhos sedimentares por meio de ICP-OES para determinar os níveis de metais (Cd, Cr, Cu, Ni, Pb e Zn) e As. O índice de carga de poluição (PLI) e o fator de enriquecimento (EF) foram calculados para identificar a toxicidade relativa dos elementos dos sedimentos e a contribuição antropogênica dos elementos investigados. Os índices indicaram a ausência de contaminação por metais pesados, mas houve uma entrada mais elevada de As nos testemunhos B2 e B5, amostrados em área com maiores taxas de sedimentação. Através de análise estatística de decomposição de séries temporais, verificou-se que o fluxo de metais para a área segue os ciclos de estações chuvosa (verão austral) e seca (inverno austral). Como conclusão pode ser verificado que o enriquecimento observado corresponde ao final do século XIX, quando o Porto de Santos foi inaugurado, e à década de 1970, quando as atividades do porto foram expandidas. Ainda, a análise dos índices e da decomposição temporal indica que a entrada de As no Canal de Bertioga dá-se por processos naturais de intemperismo e sedimentação.

The study presents an evaluation of potentially toxic elements deposition in Bertioga Channel (Southeastern Brazilian coast) along the last 150 years, the main anthropogenic activity period in the area. Five sediment cores by means of ICP-OES to determine the levels of metals (Cd, Cr, Cu, Ni, Pb and Zn) and As. The pollution load index (PLI) and enrichment factor (EF) were calculated to identify the relative elements toxicity of the sediments and the anthropogenic contribution of the investigated elements. The indexes indicated the absence of contamination but a higher input of As in cores B2 and B5, which have been sampled in an area that presents higher sedimentation rates. Through an statistical analysis of time series decomposition, it was verified that the metals flux to the area follow the cycles of rainy (austral summer and autumn) and dry seasons (austral winter and spring). In conclusion, the enrichment corresponds to the end of the 19th Century, when Santos Harbor was inaugurated, and to the 1970s, when Santos Harbor activities expanded. In addition, the analysis of the indexes and the temporal decomposition indicate that these elements' input to Bertioga Channel is due to natural processes of weathering and sedimentation.

Muitos estudos têm encontrado elementos tóxicos em cogumelos. Sabe-se que algumas espécies de cogumelos comestíveis acumulam elevados níveis de contaminantes inorgânicos, como cádmio, mercúrio e chumbo. Há cerca de duas mil espécies de cogumelos comestíveis, mas apenas 25 espécies são cultivadas e usadas como alimentos. No Brasil, as espécies mais comercializadas e consumidas são Agaricus bisporus, conhecida como Champignon de Paris; Lentinus edodes ou Shitake, e Pleurotus sp, também chamada de Shimeji ou Hiratake. Neste trabalho, o cádmio (Cd) foi determinado em amostras de cogumelos da espécie Lentinus edodes cultivadas em diversas cidades do Estado de São Paulo e algumas amostras importadas do Japão e da China. O cádmio foi determinado por espectrometria de absorção atômica com forno de grafite após digestão com a mistura de HNO3 conc. e H2O2 30%. As amostras analisadas foram cultivadas em São Paulo e importadas de dois países. Os resultados mostraram concentrações de Cd menores nos cogumelos cultivados no Estado de São Paulo (0.0079 a 0.023 mg.kg-1 in natura) do que nas amostras importadas (0.212 a 0.125 mg.kg-1 in natura). Apesar de não existirem limites máximos de tolerância para Cd em cogumelos na legislação brasileira, os resultados mostraram que os cogumelos da espécie Lentinus edodes podem ser consumidos com segurança.

Many studies have drawn attention to the occurrence and concentration of toxic elements found in the fruiting body of mushrooms. Some edible mushroom species are known to accumulate high levels of inorganic contaminants, mainly cadmium, mercury, and lead. There are about 2,000 known edible mushroom species, but only 25 of them are cultivated and used as food. In Brazil, the most marketed and consumed mushroom species are Agaricus bisporus, known as Paris champignon, Lentinus edodes, or Shitake and Pleurotus sp, also called Shimeji or Hiratake. In this study, the concentration of cadmium was determined in Lentinus edodes mushrooms from different cities in São Paulo state and some samples imported from Japan and China. The analyses were performed by graphite furnace atomic absorption spectrometry after HNO3-H2O2 digestion. The results showed a lower concentration of Cd in the mushrooms cultivated in São Paulo (0.0079 to 0.023 mg.kg-1 in natura) than that of the mushrooms cultivated abroad (0.125 to 0.212 mg.kg-1 in natura). Although there is no tolerance limit for Cd in mushrooms in Brazil, the results show that Lentinus edodes mushrooms can be safely consumed.

Estendendo-se entre as latitudes 34ºS e 22ºS, a plataforma continental sul-brasileira constitui o único setor que corresponde a um ambiente subtropical a temperado. Os estudos dos diferentes aspectos geológicos da área iniciaram-se na década de 1960 e foram recentemente retomados após os trabalhos relativos à delimitação da Zona Econômica Exclusiva. Em termos de morfologia, pode ser dividida em três setores: Embaiamento de São Paulo, Setor Florianópolis-Mostardas e o Cone do Rio Grande, cada qual definido com base em diferenças geológicas relativas a batimetria, declividade e a presença de cânions e canais. A despeito da existência de centenas de datações ao radiocarbono, a curva de variações relativas do nível do mar no Último Ciclo Glacial é ainda tema de debate. Controvérsia recente sobre as curvas de variação do nível do mar sobre as durante o Holoceno Médio e Tardio trouxe à tona a questão da amplitude das oscilações do nível do mar. Adicionalmente, poucas mas consistentes datações sugerem a ocorrência de um nível do mar elevado durante o Estágio Isotópico 3. Em termos de processos sedimentares atuais, a plataforma continental sul-brasileira exibe um controle hidrodinâmico muito forte, tanto latitudinal quanto batimétrico. O setor ao sul de 25ºS é caracterizado pela influência da pluma de água que carreia sedimentos originários do Rio da Prata, cuja presença é conspícua até 28ºS, havendo uma zona de transição entre essas duas latitudes. A plataforma externa é marcada pelo "efeito enceradeira" da Corrente do Brasil, relíquia responsável pela manutenção de uma fácies em áreas além da isóbata de 100 metros.

Extending from latitude 34ºS to 22ºS the Southern Brazilian shelf constitutes the only part of the Brazilian shelf with a subtropical to temperate environment. The studies on the different geological aspects of the area began in the 1960's and have recently been reassessed after studies related to the determination of the Economic Exclusive Zone. In terms of morphology, the Southern Brazilian shelf may be divided into three sectors, the São Paulo Bight, the Florianópolis-Mostardas Sector and the Rio Grande Cone, characterized by conspicuous differences in terms of geological determining factors, bathymetry, declivities and the presence of canyons and channels. Despite the existence of hundreds of radiocarbon datings the sea level changes curve of southern Brazil during the Last Glacial Cycle is still a matter of debate. A recent controversy on the Middle and late Holocene sea level changes curve raised the question of the amplitude of the oscillations which occurred in the period. Also, a few but relatively consistent radiocarbon datings suggest the occurrence of a high sea level during Isotope Stage 3. In terms of sedimentary cover the Southern Brazilian shelf exhibits a very strong hydrodynamic control, both latitudinal and bathymetrical. The sector southward from 25ºS is characterized by the influence of the plume of water carrying sediments originating from the Río de La Plata. Actually its presence is conspicuous up to 28ºS, with the area between this latitude and 25ºS constituting a transitional zone. In terms of bathymetry the outer shelf is marked by the "floor-polisher" effect of the Brazil Current, which is responsible for the maintenance of a relict facies in areas deeper than 100 meters.

O sistema Cananéia-Iguape (Sudeste do Brasil), consiste em um complexo de canais lagunares localizados no interior de uma Reserva da Biosfera (assim definida pela UNESCO). Não obstante, variações ambientais importantes ocorreram nos últimos 150 anos, devido à abertura de um canal artificial, o Valo Grande, conectando o Rio Ribeira de Iguape ao sistema lagunar. O objetivo deste trabalho foi determinar a história das variações ambientais no sistema lagunar, causadas pela abertura do canal artificial, através da análise das camadas superiores da coluna sedimentar de um testemunho coletado no sistema. Neste sentido, uma abordagem integrada, envolvendo variações geoquímicas e faunísticas foi utilizada. As variações ambientais ocorridas apontam para mudanças drásticas na salinidade, nos padrões de sedimentação, nas associações de foraminíferos (incluindo períodos azóicos) e, mais drasticamente, no aporte de metais para o sistema costeiro. As concentrações de Pb no testemunho coletado indicam valores duas vezes maiores do que os medidos em sedimentos contaminados do estuário de Santos, situado na zona costeira mais industrializada do Brasil.

The Cananéia-Iguape system, SE Brazil, consists of a complex of lagoonal channels, located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve. Nevertheless, important environmental changes have occurred in approximately the last 150 yrs due to the opening of an artificial channel, the Valo Grande, connecting the Ribeira de Iguape River to the lagoonal system. Our objective is to assess the historical record of the uppermost layers of the sedimentary column of the lagoonal system in order to determine the history of environmental changes caused by the opening of the artificial channel. In this sense, an integrated geochemical-faunal approach is used. The environmental changes led significant modifications in salinity, in changes of the depositional patterns of sediments and foraminiferal assemblages (including periods of defaunation), and, more drastically, in the input of heavy metals to the coastal environment. The concentrations Pb in the core analyzed here were up to two times higher than the values measured in contaminated sediments from the Santos estuary, the most industrialized coastal zone in Brazil.