Trace elements in an adjacent channel of an anthropized area: a case study of Baixada Santista, Southeastern Brazil

In recent decades, due to intensive industrialization, the Baixada Santista has undergone an intense process of environmental degradation. The metals are toxic and persistent in varying concentrations and oxidation states and may be incorporated in sediments and biota. Thus, understanding the importance of this contamination is necessary for coastal planning. This study provides a basis for understanding the levels of metal and As contamination in the Bertioga Channel (SP). The levels of Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Sc, V and Zn in superficial sediment samples were determined by ICP-OES. The degree of sediment contamination was evaluated according to the sediment quality standards set by the Canadian environmental agency (ISQG and PEL) and by statistical tests. All values were below PEL, and most of the sample values were below ISQG, except for As, Cu and Pb. From a cluster analysis, it was possible to differentiate eastern and western parts of the channel due to their distinct hydrodynamic patterns. Furthermore, it was possible to separate the trace elements by geochemical behavior, in which Cu, Pb and Zn were linked to a small anthropogenic contribution. Thus, this study detected small anthropogenic contributions from an adjacent channel of an anthropized area, but most of the results were linked to natural geochemical processes

Artificial and natural radioactivity in edible mushrooms from Sao Paulo, Brazil

Environmental biomonitoring has demonstrated that organisms such as crustaceans, fish and mushrooms are useful to evaluate and monitor both ecosystem contamination and quality. Particularly, some mushroom species have a high capacity to retain radionuclides and some toxic elements from the soil and the air. The potential of mushrooms to accumulate radionuclides in their fruit-bodies has been well documented. However, there are no studies that determine natural and artificial radionuclide composition in edible mushrooms, in Brazil. Artificial (137Cs) and natural radioactivity (40K, 226Ra, 228Ra) were\ud determined in 17 mushroom samples from 3 commercialized edible mushroom species. The edible mushrooms collected were Agaricus sp., Pleurotus sp. and Lentinula sp. species. The activity measurements were carried out by gamma spectrometry. The levels of 137Cs varied from 1.45 0.04 to 10.6 0.3 Bq kg 1, 40K levels varied from 461 2 to 1535 10 Bq kg 1, 226Ra levels varied from 14 3 to 66 12 Bq kg 1 and 228Ra levels varied from 6.2 0.2 to 54.2 1.7 Bq kg 1. 137Cs levels in Brazilian mushrooms are in accordance with the radioactive fallout in the Southern Hemisphere. The artificial and natural activities determined in this study were found to be below the maximum permissible levels as\ud established by national legislation. Thus, these mushroom species can be normally consumed by the population without any apparent risks to human health

Reatividade de Metais e B (Boro) no Sistema Estuarino de Cananéia-Iguape (Litoral Sul de São Paulo, Brasil)

Dissolved elements reactivity in water column directly influences their chemical and toxic behavior, and in their bioavailability, therefore, in their environmental profile in estuarine systems, important for their great biological productivity and location in zones with potential anthropic impacts. In this context, this study evaluated the behavior of metals (Ba, Fe, Li, Mn and Zn) and  the semimetal B throughout the estuarine mixture in the Estuarine System of Cananéia-Iguape. It was observed that B and Li presented conservative behavior as they are not reactive, Ba, Fe and Zn presented not conservative behavior with removal in low salinities, and Mn presented mixed behavior, with addition in low salinities and approximately conservative behavior in high salinities.La reactividad de los elementos disueltos en la columna de agua directamente influye en el comportamiento químico, tóxico en su biodisponibilidad, por último, en su perfil ambiental en los sistemas estuarinos son importantes porque son áreas de alta productividad biológica y se encuentran principalmente en áreas con potenciales impactos humanos. Teniendo en cuenta este contexto, el presente estudio se evaluó el comportamiento de los metales (Ba, Fe, Li, Mn y Zn) y B semimetal a lo largo de la mezcla del estuario sistema estuarino Cananéia-Iguape. Como resultado principal, encontramos que B y Li se comportó conservador por no ser reactivo, Ba, Fe y Zn mostraron conservador no con la eliminación en condiciones de alta salinidad, y Mn mostraron un comportamiento mixto, además de bajas salinidades y el comportamiento de aproximadamente conservador en condiciones de alta salinidad. Con la información de la reactividad de los elementos, puede en futuros estudios que permitan identificar a las especies dominantes química en la que los niveles de salinidad, por lo tanto verificar su toxicidad y los posibles riesgos ambientales en el área de estudio.A reatividade de elementos dissolvidos na coluna de água influencia diretamente no comportamento químico, tóxico, na sua biodisponibilidade, enfim, no seu perfil ambiental em sistemas estuarinos, importantes por serem áreas de grande produtividade biológica e por estarem localizados principalmente em zonas com potenciais impactos antrópicos. Considerando este contexto, o presente trabalho avaliou o comportamento de metais (Ba, Fe, Li, Mn e Zn) e do semimetal B ao longo da mistura estuarina do Sistema Estuarino de Cananéia-Iguape. Como resultados principais, observou-se que B e Li apresentaram comportamento conservativo por não serem reativos, Ba, Fe e Zn apresentaram comportamento não conservativo com remoção em altas salinidades, e Mn apresentou comportamento misto, com adição em baixas salinidades e comportamento aproximadamente conservativo em altas salinidades. Com as informações de reatividade de elementos, pode-se em futuros estudos identificar qual a espécie química dominante em quais níveis de salinidade, assim verificando sua toxicidade e possíveis riscos ambientais na área de estudo

ESTUDO DO ASSOREAMENTO DO RESERVATÓRIO TANQUE GRANDE, GUARULHOS (SP)

O reservatório Tanque Grande, implantado na bacia homônima de 7,75 km2 , localizada ao norte do município de Guarulhos (SP), é um dos reservatórios de abastecimento municipal, atendendo a uma população de cerca de 40.000 habitantes. Apesar de sua importância ambiental e estratégica, o reservatório tem sido afetado pelo assoreamento de seu contribuinte principal, o ribeirão Tanque Grande, reduzindo a sua capacidade de armazenamento. Com o objetivo de avaliar o assoreamento do reservatório, foram pesquisados depósitos de assoreamento e a produção específica de sedimentos da principal bacia contribuinte. Os depósitos, com cerca de 30.500 m3 (ou 45.800 t), são constituídos de material silto-argiloso, e ocupam cerca de 35% do volume do reservatório. Datação radiométrica pelo método do 210Pb confirmou o início da deposição com o início do enchimento do reservatório em cerca de 50 anos, indicando uma produção bruta de sedimentos de 916 t/ano e uma produção específica de 118 t/ km2 .ano. As estradas foram identificadas como sendo a principal área-fonte de sedimentos, bem como meio de sua transferência ao ribeirão Tanque Grande. Palavras-chave: assoreamento de reservatório, produção específica, volumetria de depósitos

Assessment of historical fecal contamination in Curitiba, Brazil, in the last\ud 400 years using fecal sterols

A 400-year sedimentary record of the Barigui River was investigated using fecal biomarkers and nutrient distribution. The temporal variability in cholesterol, cholestanol, coprostanol, epicoprostanol, stigmastanol, stigmasterol, stigmastenol, sitosterol, and campesterol between 1600 and 2011 was assessed. Anthropogenic influences, such as deforestation and fecal contamination from humans and livestock, were observed from\ud 1840. The sterol ratios exhibit evidence of hens, horses, cows, and an unknown herbivore, which may be a capybara (Hydrochoerus hydrochaeris), from1820 and has been observed moremarkedly from1970 onward. Human fecal contamination was detected from 1840 and was observed more markedly from 1930 due to population growth. Thus, the sanitation conditions and demographic growth of Curitiba seemed to be the main factors of human sewage pollution, as the coprostanol concentration over timewas strongly correlatedwith the population growth (r= 0.71, p b 0.001) although diagenetic processes have also been observed

Reconstruction of historical trends in potentially toxic elements from sediment cores collected in Bertioga channel, southeastern Brazil

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.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

Control of oceanic circulation on sediment distribution in the southwestern Atlantic margin (23 to 55º S)

In this study, we interpret the role played by ocean circulation in sediment distribution on the southwestern Atlantic margin using radiogenic Nd and Pb isotopes. The latitudinal trends for Pb and Nd isotopes reflect the different current systems acting on the margin. The utilization of the sediment fingerprinting method allowed us to associate the isotopic signatures with the main oceanographic features in the area. We recognized differences between Nd and Pb sources to the Argentinean shelf (carried by the flow of Subantarctic Shelf Water) and slopes (transported by deeper flows). Sediments from Antarctica extend up to the Uruguayan margin, carried by the Upper and Lower Circumpolar Deep Water. Our data confirm that, for shelf and intermediate areas (the upper 1200 m), the transfer of sediments from the Argentinean margin to the north of 35∘ S is limited by the Subtropical Shelf Front and the basin-wide recirculated Antarctic Intermediate Water. On the southern Brazilian inner and middle shelf, it is possible to recognize the northward influence of the Río de la Plata sediments carried by the Plata Plume Water. Another flow responsible for sediment transport and deposition on the outer shelf and slope is the southward flow of the Brazil Current. Finally, we propose that the Brazil–Malvinas Confluence and the Santos Bifurcation act as boundaries of geochemical provinces in the area. A conceptual model of sediment sources and transport is provided for the southwestern Atlantic margin

Baseline concentrations of faecal sterols and assessment of sewage inputinto different inlets of Admiralty Bay, King George Island, Antarctica

The Antarctic region is one of the best preserved environments in the world. However, human activities such as the input of sewage result in the alteration of this pristine site. We report baseline values of faecal sterols in Admiralty Bay, Antarctica. Four sediment cores were collected during the 2006/2007 austral summer at the Ezcurra (THP and BAR), Mackelar (REF) and Martel (BTP) inlets. Concentrations of faecal sterols (coprostanol + epicoprostanol) were <0.16 lg g_1, suggesting no sewage contamination and probable ‘‘biogenic’’ contributions for these compounds. Baseline values, calculated using the mean\ud concentration of faecal sterols in core layers for THP, BAR, REF and BTP, were 0.04 } 0.02, 0.03 } 0.01, 0.07 } 0.01 and 0.04 } 0.02 lg g_1, respectively. These results established as natural contributions of faecal sterols, suggesting that these markers can be useful indicators of human-derived faecal inputand contributing to monitoring programs to prevent anthropogenic impacts

From sambaquis (shell mounds) to plastic debris: a summary of the geological imprint of human occupation in the coast of São Paulo (Southeast Brazil)

In this work, we present a brief revision of the geological evidence of human activities in the coast of São Paulo (Southeast Brazil), from pre-historical times to the present. We analyze case studies in different sectors of the coast, identifying the main historical causes that resulted in environmental changes with their consequent imprint in the sedimentary column. There was a south-to-north trend inthe occupation at the colonization period (1500 onwards), essentially determined by differences in the geomorphology of the area. Finally, the accumulation of artificial radionuclides and plastic debris in the sediments is discussed

Characterization of sources and temporal variation in the organic matter input indicated by n-alkanols and sterols in sediment cores from Admiralty Bay, King George Island, Antarctica

The Antarctic continent is one of the most protected areas on the planet, but is dynamically responding to environmental change on a global scale. Change in the air temperature may affect the organic matter production in the area. Biomarkers such as sterols, n-alkanols and phytol in three sediment cores from Admiralty Bay, Antarctica, were determined to identify the type of organic matter, variation in input and possible relationship with general temperature changes over the past decades. The\ud concentrations ranged from 0.91 to 13.99 lg g-1 (dry weight) of total sterols, 0.20–2.14 lg g-1 of total n-alkanols and 0.13–2.38 lg g-1 of phytol. Cholest-5-en-3b-ol was the most abundant sterol. The fecal sterols, 5b-cholestan- 3b-ol and 5b-cholestan-3a-ol, occurred at low concentration (\0.01–0.15 lg g-1), below the baseline values for this region. The lower carbon chain n-alkanols were more abundant, which suggested that algae, bacteria and zooplankton were the primary sources of the sedimentary organic matter. Phytol exhibited little variation across all of the cores, which appears to be the result of degradation. Variation in the concentration of compounds in one core was compared with the variation in mean air temperature (MAT) over time; this preliminary association showed a tendency toward increased concentration during the period in which the MAT was more elevate