MARCOS ANTONIO HORTELLANI
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Artigo IPEN-doc 27728 Emerging contaminants (Rh, Pd, and Pt) in surface sediments from a Brazilian subtropical estuary influenced by anthropogenic activities2021 - BERBEL, GLAUCIA B.B.; HORTELLANI, MARCOS A.; SARKIS, JORGE E. de S.; CHIOZZINI, VITOR G.; FAVARO, DEBORAH I.T.; SUTTI, BRUNO O.; SAKAZAKI, NIXON C.; BRAGA, ELISABETE de S.The concentrations of Platinum (Pt), Rhodium (Rh) and Palladium (Pd) were evaluated from a highly impacted estuary in Brazil influenced by industrial pole, highway traffic and sewage outfall. The Santos-São Vicente region presents important economic activities derived from a largest harbor of Latin America and an industrial pole surrounded by intensive highway traffic. Values of Rh varied from 0.08 to 1.7 ng g−1 with highest values at stations impacted by domestic waste. Pt ranged from 0.15 to 40.3 ng g−1 with highest concentrations located close to the ferryboat traffic. Pd levels varied from 1.05 to 22.0 ng g−1 with values >5 ng g−1 in 50% of the stations. The spatial distribution of PGEs was not always directly associated with muddy sediments, because high PGE levels found even in sandy sediments. Pollution indexes, including anthropogenic factor (AF), geoaccumulation index (Igeo), Enrichment factor (EF), and Pollution Load Index (PLI) were used for evaluating contaminant potential. Based on EF, Igeo, and PLI, 50% of samples of the sediments from Santos-São Vicente Estuarine System (SSV) were classified with significant to strong PGE contamination. All stations on the Santos Channel (SC), São Vicente Channel (SVC) and Bertioga Channel (BC) had AF higher than 80% in at least one of PGE elements, as showed in station 2A, which presented AF <50% for Rh and Pd and 86% for Pt. Despite high anthropogenic enrichment, no correlations among PGE elements were observed in surface sediments. Only two stations presented Pd/Pt, Pt/Rh, and Pd/Rh typical ratios of auto catalyst (st. 14 and Piaçaguera) both located in the vicinity of highways. This could be due to the PGE deposition process in road dust, soil, and water as well as the biogeochemical cycling of PGEs involving organic metallic and inorganic complexes formed in the estuarine and seawaters.Artigo IPEN-doc 25783 In vitro biocompatibility of new bioactive lithia-silica glass-ceramics2019 - DAGUANO, JULIANA K.M.B.; MILESI, MARIANA T.B.; RODAS, ANDREA C.D.; WEBER, ALINE F.; SARKIS, JORGE E.S.; HORTELLANI, MARCOS A.; ZANOTTO, EDGAR D.Glass-ceramics based on the Li2O-SiO2 system have been extensively used as restorative dental materials due to their excellent chemical durability, aesthetics, inertness in the buccal environment, and high fracture strength; but they are not bioactive. On the other hand, all known bioactive glasses show ability to bond to bone, teeth and cartilage coupled to osteoconduction and osteoinduction, but their fracture strength and toughness are rather low. The aim of this study is to develop and evaluate the in vitro biocompatibility of a new type of (bioactive and strong) lithia-silica glass-ceramic. For these purposes, two types of glass-ceramics based on a multicomponent lithia-silica system were studied: lithium metasilicate (LM) and lithium disilicate (LD). The in vitro bioactivity study was conducted in a SBF solution, before and after different times of immersion; the new materials were analyzed by XRD, FTIR, and SEM. Some samples were subjected to in vitro biodegradation tests to quantify the release of lithium and the weight loss. Cytotoxicity, adhesion, and cell proliferation on different samples were examined by using the Methyl Tetrazolium salt (MTS) and Alizarin Red. For ~40 vol% crystallinity, lithium metasilicate was detected as the major phase, whereas for ~80 vol% crystallinity, lithium disilicate was the major phase. The LD proved to be strong (3p-bending strength of 233 ± 12 MPa) and bioactive after 14 days of immersion in SBF. In terms of lithium ion release, the LD was outside the toxic range (> 8.3 ppm). The LM and LD are not cytotoxic. The LD shows the best cellular adhesion and proliferation, leading to the formation of a mineralized matrix after 21 days. These results clearly suggest that the new LD brand is strong and highly biocompatible and warrants further study.Artigo IPEN-doc 23182 Effects of harbor activities on sediment quality in a semi-arid region in Brazil2017 - MOREIRA, LUCAS B.; CASTRO, ITALO B.; HORTELLANI, MARCOS A.; SASAKI, SILVIO T.; TANIGUCHI, SATIE; PETTI, MONICA A.V.; FILLMANN, GILBERTO; SARKIS, JORGE E.S.; BICEGO, MARCIA C.; COSTA-LOTUFO, LETICIA V.; ABESSA, DENIS M.S.Tropical marine environments are rich in biodiversity and the presence of harbor activities in these areas can harm the coastal ecosystems. In this study, we assessed sediment quality of two harbors from a tropical region in Brazil by applying multiple lines-of-evidence approach. This approach included the integration of results on: (1) grain size, organic matter, organic carbon, nitrogen, phosphorus, trace metals, polycyclic aromatic hydrocarbons, linear alkylbenzenes, and tributyltin; (2) acute toxicity of whole sediments and chronic toxicity of liquid phases; and (3) benthic community descriptors. Our results revealed that the main contaminants detected in sediments from Mucuripe and Pecém Harbors were chromium, copper, nitrogen, zinc, and tributyltin. These toxicants arise from typical harbor activities. However, the changes in benthic composition and structure appear to depend on a combination of physical impacts, such as the deposition of fine sediments and the toxic potential of contaminants, especially in Mucuripe. Thus, apart from toxicants physical processes are important in describing risks. This information may assist in management and conservation of marine coastal areas.Artigo IPEN-doc 21220 An environmental forensic approach for tropical estuaries base on metal bioaccumulation in tissues of Callinectes danae2016 - BORDON, ISABELLA C.A.C.; SARKIS, JORGE E.S.; ANDRADE, NATHALIA P.; HORTELLANI, M.A.; FAVARO, DEBORAH I.T.; KAKAZU, MAURICIO H.; COTRIM, MARYCEL E.B.; LAVRADAS, RAQUEL T.; MOREIRA, ISABEL; SAINT'PIERRE, TATIANA D.; HAUSER-DAVIS, RACHEL A.The blue crab Callinectes danae is distributed throughout the Atlantic coast and this study aimed to evaluate a environmental forensics approach that could be applied at tropical estuarine systems where this species is distributed, based on the metal concentrations in its tissues. For this purpose, blue crab samples were collected in 9 sites (distributed in 3 areas) along the Santos Estuarine System, state of Sa˜o Paulo, Brazil. The concentrations of Al, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb and Zn were determined in gills, hepatopancreas and muscle tissues. Sediment samples were collected and analyzed in these same sites. A data distribution pattern was identified during both sampling periods (August and December 2011). In order to validate this model, a new sampling campaign was performed in March 2013 at the Santos Estuarine System and also at Ilha Grande (state of Rio de Janeiro). These data were added to the previous database (composed of the August and December 2011 samples) and a discriminant analysis was applied. The results confirmed an environmental fingerprint for the Santos Estuarine System.