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1.
Sci Total Environ ; 951: 175551, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39151623

RESUMEN

Despite being one of the most remote areas on the planet, the Antarctic continent is subject to anthropogenic influences. The presence of various groups of contaminants, including persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), has been documented in the region over the past decades. However, a significant knowledge gap remains regarding the detection of new pollutants, such as emerging contaminants (ECs), in Antarctic coastal environments. This study analyzed the occurrence and levels of selected POPs, PAHs, ECs in surface sediments from Admiralty Bay, Antarctica Peninsula. Non-target screening was employed to identify potential novel contaminants in the region. Samples (n = 17) were extracted using an accelerated solvent extraction (ASE) system and instrumental analyses were performed using gas chromatography coupled to a triple-quadrupole mass spectrometer (GC/MS-MS). Regarding regulated contaminants, concentrations of Σ5PCBs ranged from

2.
Mar Pollut Bull ; 174: 113263, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34952404

RESUMEN

The presence and distribution of persistent organic pollutants (POPs) and contaminants of emerging concern (CECs) were evaluated in spinner dolphins (Stenella longirostris) from the Fernando de Noronha Archipelago (Western Atlantic Ocean). Blubber samples (n = 37) were Soxhlet extracted and analyzed using gas chromatography tandem mass spectrometry. The levels of POPs reported in this study are far below those previously reported in spinner dolphins from the Indian and Pacific Oceans. Despite relatively low levels of contaminants, the presence of chemicals represents an additional stressor to these marine mammals, which are subject to increasing anthropogenic pressures, especially regarding tourism activities, in Fernando de Noronha.


Asunto(s)
Stenella , Animales , Efectos Antropogénicos , Océano Atlántico , Cromatografía de Gases y Espectrometría de Masas , Contaminantes Orgánicos Persistentes
3.
Mar Pollut Bull ; 173(Pt A): 112952, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34536707

RESUMEN

A large-scale oil spill has reached over 3000 km of the NE Brazilian coast since August 2019. The cause and origin of this spill remain mysterious, and the impacts on coastal ecosystems have not been clearly understood so far. Despite the efforts to remove the oil (mainly from local communities), oil stains are still present in beaches, mangroves, and beachrocks. In this short report, we describe the occurrence of the barnacle Chthamalus bisinuatus Pilsbry, 1916 colonizing oil spill stains on intertidal surfaces of beachrocks one year after the first oil records. We quickly assessed oil stains across three different reefs located at the Conde municipality, Bahia (NE Brazil), where the species was identified and its density on oil stains calculated. The occurrence of barnacles in oil stains was restricted to zones in the wake of the reefs. Their densities varied from 0 to 238 ind./dm2, with an average of 34 ± 68 ind./dm2. If we account for dead individuals (empty barnacle plates), they correspond to 25.9% of the sampled population. The presence of oil possibly affected barnacle survival rates but did not seem to prevent barnacle individuals from reaching adult sizes. We also found individuals of the snail Echinolittorina lineolata (d'Orbigny, 1840) crawling on these barnacles, indicating that the barnacle assemblages on oil stains are stable enough to provide refuge for these snails. It is not clear if the presence of barnacles on oil reflects the resistance of these crustaceans to the oil toxicity or is just a result of a low substrate selectivity by the cypris larvae.


Asunto(s)
Contaminación por Petróleo , Thoracica , Animales , Brasil , Ecosistema , Humanos , Invertebrados
4.
Mar Pollut Bull ; 161(Pt B): 111818, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33160119

RESUMEN

The occurrence and spatial distribution of persistent organic pollutants (POPs) and personal care products (PCPs) were investigated in surface sediments of Todos os Santos Bay. Samples were Soxhlet-extracted and analyzed by gas chromatography coupled with tandem mass spectrometry. Quantification limits (QL) ranged from 0.0025 ng g-1 for POPs to 0.25 ng g-1 for PCPs. Of the POPs studied, only PCBs and DDTs were detectable, with concentrations ranging from

Asunto(s)
Cosméticos , Bifenilos Policlorados , Contaminantes Químicos del Agua , Bahías , Brasil , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas , Sedimentos Geológicos , Contaminantes Orgánicos Persistentes , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis
5.
Mar Pollut Bull ; 156: 111219, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32366367

RESUMEN

Large amounts of crude oil were found along Brazil's northeast and southeast seaboard from August 2019 to January 2020. Petroleum companies and oil tankers reported no accidents previously or during this period. The stranded oil on Brazilian beaches looks like tar; it has solid aspect and is denser than seawater. Chemical characterization of this oil showed that light hydrocarbons were still present, increasing the probability of negative effects to coastal organisms and ecosystems upon release in the water column. Diagnostic ratios, chromatogram pattern, and percentage-weathering plots proved that the oil samples share the same oil source. This work provides data for future comparison with oil samples that will likely be found stranded along the Brazilian shoreline in the years to come, helping to understand long term issues associated with the mysterious oil spill that made landfall in late 2019.


Asunto(s)
Contaminación por Petróleo , Petróleo/análisis , Contaminantes Químicos del Agua/análisis , Brasil , Ecosistema , Monitoreo del Ambiente
6.
Sci Total Environ ; 706: 136017, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31855633

RESUMEN

Levels and fluxes of Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHs), including n-alkanes and petroleum biomarkers (PBMs), were measured in a sedimentary core from a nominated RAMSAR (Guaratuba Bay, Brazil) subtropical estuary experiencing relatively low human impacts, to describe the evolution of anthropogenic activities over the last century. TOC contents varied from 0.80 to 1.25%. No significant correlation between hydrocarbons and TOC with grain size (predominantly sand) was observed. Concentration and flux of total AHs ranged from 65.5 to 195 µg g-1 and 27.6 to 82.0 µg cm-2 y-1, respectively, with the highest levels found in 1960-1966, when access routes to Guaratuba city were improved. Diagnostic ratios based on AH components showed an apparent change in the sources over time, with biogenic origins prevailing until 1966-1971, followed by subsequent increases in petroleum sources. Petroleum tricyclic terpanes were detected in the core (0.40 to 3.0 µg g-1), suggesting the use of lubricating oil in the bay area. Hopanes were mainly attributed to biological sources. Concentration and flux of total PAHs ranged from 8.65 to 35.9 ng g-1 and 3.64 to 15.1 ng cm-2 y-1, respectively, with the highest levels found in the top core section, reflecting recently increased human activity, while a peak PAH concentration at approximately 1977-1983 can be assumed to be a delayed signal of increased human occupation as a consequence of the improvement of access roads to the area, which started in the 1960s. Alkylated were the most abundant group of PAHs throughout the core. Despite relatively low concentrations of hydrocarbon deposition over approximately 90 years, this study highlights the influence of human occupation and slight petroleum contamination in this preserved area, mainly in recent core sections.

7.
Chemosphere ; 241: 125029, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31604196

RESUMEN

The sources and depositional history of polycyclic aromatic hydrocarbons (PAHs) and organochlorine compounds (OCs) over the last century were investigated in sediment cores from the North Adriatic Sea (Po River prodelta) and the South-Western Adriatic Margin (SWAM). Contaminant concentrations were higher in the Po River prodelta. ∑16PAHs ranged from 193 to 533 ng g-1, ∑5PCBs ranged from 0.9 to 5.2 ng g-1 and ∑DDTs (p,p'-DDD + p,p'-DDE) ranged from 0.1 to 2.5 ng g-1. In the SWAM, ∑PAHs ranged from 11 to 74 ng g-1 while ∑PCB and ∑DDT concentrations were close to the MQL. Accordingly, contaminant fluxes were much higher in the northern (mean values of 152 ±â€¯31 ng cm2 y-1 and 0.70 ±â€¯0.35 ng cm2 y-1 for PAHs and OCs, respectively) than in the southern Adriatic (2.62 ±â€¯0.9 ng cm2 y-1 and 0.03 ±â€¯0.02 ng cm2 y-1 for PAHs and OCs, respectively). The historical deposition of PAHs seemed to be influenced by the historical socioeconomic development and by changes in the composition of fossil fuel consumption (from petroleum derivatives to natural gas) in Italy from the end of the 19th century to the present. Similarly, vertical variations in DDT concentrations matched its historical use and consumption in Italy, which started around in the mid-late 1940s to fight typhus during the II World War. Contaminant concentrations detected in sediments does not seem to pose ecotoxicological risk for marine organisms in the Adriatic Sea.


Asunto(s)
DDT/análisis , Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Bifenilos Policlorados/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Monitoreo del Ambiente/historia , Combustibles Fósiles/análisis , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Hidrocarburos Clorados/análisis , Italia , Ríos/química , Contaminantes Químicos del Agua/análisis
8.
Chemosphere ; 223: 608-615, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30798056

RESUMEN

Microplastics are important vectors for the transport and accumulation of persistent organic contaminants in coastal and marine environments. We determined the concentration of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) associated with microplastic pellets collected along a 39-km stretch of Brazil's South Atlantic coastline to understand the spatial dynamics and potential risk posed by these contaminants. Total PAH concentrations ranged from 1,454 to 6,002 ng g-1 and regularly exceeded the threshold effect level (TEL) for sediments defined by the United States Environmental Protection Agency. Sampling stations, spaced evenly along the coastline (i.e., 3-km intervals) exhibited a general north-to-south decline in the concentrations of some PAHs, but this spatial gradient was complicated by small-scale differences in the concentrations and composition of associated contaminants. Similarly, analysis of individual isomer ratios revealed further complexity driven by differences in the contribution of petrogenic versus pyrolytic inputs which pose different levels of risk to marine organisms. PCB concentrations ranged from 0.8 to 104.6 ng g-1 and were dominated by low chlorinated congeners likely to have originated from major industrial areas to the north. Overall, this study highlights the challenge of directly linking microplastic pollution with the potential toxicological effects of organic contaminants in coastal waters. We recommend that monitoring programs should explicitly consider both the origin (i.e., pellet sources and dispersal pathways) and nature of organic contamination (i.e., concentration and composition) when assessing the risks for biota and human health.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Plásticos/efectos adversos , Bifenilos Policlorados/efectos adversos , Hidrocarburos Policíclicos Aromáticos/efectos adversos , Contaminantes Químicos del Agua/efectos adversos , Océano Atlántico , Humanos , Medición de Riesgo
9.
Mar Pollut Bull ; 133: 436-441, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30041333

RESUMEN

The occurrence, distribution, and the total mass of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were studied in surficial sediments of the Paranaguá Estuarine System (PES), a subtropical estuary in Southern Atlantic. Altogether, concentrations and inventories of contaminants ranged from <0.06 to 4.78 ng g-1 and < 0.13 to 10.47 ng cm-2, respectively. OCPs presented the higher total mass (10.85 kg) and a decreasing trend from the inner estuary towards the adjoining shallow shelf. The occurrence of PCBs was restricted to sites nearby urban and industrial areas, which accumulated ~80% of the total mass of PCBs. Although the level of contamination is low, the results refer to recent years, which mean that the actual values could be greater if sediments from periods of higher usage were analyzed. This study provides the first estimates of POPs (persistent organic pollutants) total mass in the PES, contributing to data for the Southern American inventories.


Asunto(s)
Estuarios , Sedimentos Geológicos/análisis , Hidrocarburos Clorados/análisis , Contaminantes Químicos del Agua/análisis , Océano Atlántico , Brasil , Monitoreo del Ambiente/métodos , Halogenación , Plaguicidas/análisis , Bifenilos Policlorados/análisis
10.
Sci Total Environ ; 605-606: 980-994, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28693111

RESUMEN

Contamination of aquatic systems by no longer used but very persistent compounds (e.g., organochlorine pesticides) and newly detected chemicals, such as personal care products (PCPs), represents a raising concern. In this study, we carried out one of the first comparisons of both types of contaminants, legacy and emerging, in two coastal systems (Cadiz Bay and Huelva Estuary). A wide range of analytes were selected to this end, including hydrocarbons, UV filters, fragrances, and antimicrobials. Analysis of surface sediments revealed the occurrence of 46 out of 97 target analytes, most of them predominantly accumulated in depositional areas with high organic carbon content. Polycyclic aromatic hydrocarbons (PAHs), fragrances (e.g., octahydrotetramethyl acetophenone or "OTNE"), UV filters (e.g., octocrylene), and nonylphenol had the highest concentrations (up to 1098, 133.5, 72 and 575ngg-1, respectively). Several inputs were detected, from atmospheric deposition after combustion to wastewater discharges and recreational activities. However, an environmental risk assessment performed for those chemicals for which ecotoxicological data were available, indicated that legacy compounds still pose the highest potential risk towards benthonic organisms (individual hazard quotients up to 580 for dichlorophenyldichloroethylene or "DDE") compared to PCPs.

11.
Mar Pollut Bull ; 118(1-2): 447-451, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-28325610

RESUMEN

Temporal patterns, fluxes and inventories of polychlorinated biphenyls (PCBs) were assessed in nine sediment cores collected from selected areas of Admiralty Bay off the Antarctic Peninsula. Concentrations of total PCBs were low, but slightly higher in comparison to low-impacted, remote environments in the world, ranging from below the detection limit to 11.9ngg-1 in dry weight. PCB concentrations and inventories suggest a possible minor influence related to the nearby logistic activities, especially in the sediment core collected close to the Ferraz Station. Despite being the most remote and protected area on the planet, the Antarctic continent is no longer a pristine environment.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Regiones Antárticas , Bahías , Islas
12.
Environ Pollut ; 218: 1055-1064, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27574801

RESUMEN

The spatial distributions and fates of selected legacy and emerging compounds were investigated and compared in surface sediments sampled along the Adriatic mud-wedge and in deep-sea regions from the southern Adriatic basin. Results indicated that the concentrations of legacy contaminants (PAHs, PCBs and DDTs) and emerging contaminants (tonalide, galaxolide, EHMC, octocrylene, BP3 and NP) ranged from 0.1 to 572 ng g-1 and from

Asunto(s)
Sedimentos Geológicos/química , Bifenilos Policlorados/química , Ríos/química , Agua de Mar/análisis , Contaminantes Químicos del Agua/química , Monitoreo del Ambiente , Hidrocarburos Policíclicos Aromáticos/química
13.
Sci Total Environ ; 562: 580-587, 2016 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-27110972

RESUMEN

Sources, historical trends and inventories of polychlorinated biphenyls (PCBs) were investigated in sediments collected in five transects along the north-south axis of the western Adriatic Sea. The concentration of total PCBs (∑28 PCBs) ranged from

Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Italia , Océanos y Mares
14.
Mar Pollut Bull ; 70(1-2): 247-52, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23499537

RESUMEN

This study evaluated the occurrence and distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in 22 surface sediment samples and one core collected in Guaratuba Bay, a large and well-preserved estuary in Southern Atlantic, Brazil. The concentration of PCBs in the superficial sediment samples ranged from

Asunto(s)
Bahías/química , Hidrocarburos Clorados/análisis , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Contaminantes Químicos del Agua/análisis , Brasil , Monitoreo del Ambiente , Estuarios , Contaminación Química del Agua/estadística & datos numéricos
15.
Arch Environ Contam Toxicol ; 64(4): 573-82, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23355046

RESUMEN

The Paranaguá Estuarine System (PES) is an important estuarine environment on the Brazilian coast. The economic importance of the PES is mainly related to industries, fuel terminals, and the main South American grain-shipping port. The aim of this work was to determine the vertical distribution of polychlorinated biphenyls (PCBs) in three sediment cores from the PES. The methods included Soxhlet extraction, clean-up, and quantification by gas chromatography with electron capture detection. The concentrations of total PCBs ranged from lower than the detection limit to 6.65 ng g(-1). Low PCB concentrations were detected in P1 and P3, which were collected far away from direct human activities. In P2, the compositional pattern of PCB congeners showed greater concentrations of tetra- and penta-chlorinated congeners associated with urban and port activities near Paranaguá city. The differences in concentrations between the three sediment cores were attributed to the distance of the sampling points in relation to the possible sources of pollution, which are mostly related to Paranaguá city. The vertical distribution of PCBs in the sediment core P2 was related to historical anthropogenic activities. The highest PCB input was from 1970 to the early 1990s, which coincides with a period of greater use of PCBs in Brazil as well as their greater worldwide production.


Asunto(s)
Grano Comestible/química , Monitoreo del Ambiente , Bifenilos Policlorados/análisis , Agua de Mar/química , Navíos , Contaminantes Químicos del Agua/análisis , Brasil , Cromatografía de Gases , Estuarios , Sedimentos Geológicos/química , Límite de Detección , Factores de Tiempo
16.
Sci Total Environ ; 417-418: 158-68, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22244354

RESUMEN

The sources and concentrations of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs), faecal and biogenic sterols, and trace metals at 10 sampling sites located in Laranjeiras Bay, a large Environmental Protection Area in the southern Atlantic region of Brazil, were determined to assess the sources of organic matter and the contamination status of estuarine sediments. Organic compounds were determined by GC-FID and GC-MS, and ICP-OES was used to evaluate trace metals. The total AHs concentration ranged from 0.28 to 8.19 µg g(-1), and n-C(29) and n-C(31) alkanes were predominant, indicating significant inputs from higher terrestrial plants. Unresolved complex mixtures (UCM) were not detected at any site, suggesting that the study area was not significantly contaminated by fossil fuels. The total PAH concentration varied from 3.85 to 89.2 ng g(-1). The ratio between selected PAH isomers showed that combustion of biomass, coal, and petroleum is the main source of PAHs in the study area. The concentrations of the faecal sterols coprostanol and epicoprostanol were below the detection limits, suggesting that sewage was not a significant contributor to sedimentary organic matter. The concentrations of the trace metals (As, Cr, Cu, Ni, Pb and Zn) were low, except near sites located at the mouths of rivers that discharge into the study area and near urbanised regions (Paranaguá city and the adjoining harbour). In general, the concentrations of PAHs were below the threshold effect concentrations (TEL) levels. Although the As, Cr and Ni concentrations were above the TEL levels, the study area can be considered as preserved from human activities.


Asunto(s)
Sedimentos Geológicos/química , Contaminantes Químicos del Agua/análisis , Alcanos/análisis , Bahías , Brasil , Ergosterol/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Sitoesteroles/análisis , Oligoelementos/análisis
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