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1.
J Environ Manage ; 261: 110169, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32148261

RESUMO

The bioremediation of an oily sludge (321 ± 30 mg of polycyclic aromatic hydrocarbons/kgDRY SLUDGE and 13420 ± 1300 mg of aliphatic hydrocarbons/kgDRY SLUDGE) by mixture with contaminated soil (23 ± 2 mg of polycyclic aromatic hydrocarbons/kgDRY SOIL and 98 ± 10 mg of aliphatic hydrocarbons/kgDRY SOIL) was studied. Furthermore, the effect of oxidative pretreatments (persulfate and permanganate) on the performance of the global process was examined. The treatments reached contamination levels lower than the original residues, indicating the presence of synergic processes between a highly contaminated sludge and soil with a selected hydrocarbon-degrading community. Pretreatment with permanganate significantly improved biodegradation, possibly due to the increase in bioavailability and biodegradability of petroleum hydrocarbons. Two months of incubation was enough to reach the complete elimination of polycyclic aromatic hydrocarbons and 92% elimination of aliphatic hydrocarbons. Monitoring using five parameters (concentration of total petroleum hydrocarbons, total cultivable heterotrophic bacteria count, lipase and dehydrogenase activities, and polycyclic aromatic hydrocarbon-degrading bacteria count) as an approach for a preliminary scanning of the effectiveness of a treatment is proposed based on principal components analysis.


Assuntos
Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Hidrocarbonetos , Compostos de Manganês , Óxidos , Esgotos , Solo , Microbiologia do Solo
2.
Waste Manag ; 105: 433-444, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32126371

RESUMO

Different percolation tests were developed worldwide to characterize the leaching and to evaluate the environmental compatibility of granular materials. The German standard up-flow percolation test has a short testing time and can be used for both coarse and fine-grain materials. Some very fine-grain materials are difficult to percolate. According to the standard, admixture of 80% quartz sand (20% material) can be used for cohesive materials. It is assumed that equilibrium concentrations are reached and therefore the sand does not cause any interfering processes. However, the 80% sand admixture cannot be used for coarse materials due to dilution. A standardized sand admixture for both coarse and fine-grain materials is beneficial for the routine of laboratories. The sand admixture has the further advantage that it reduces the testing time. The experimental and the analysis procedures of the German standard were checked, specified, and optimized. An admixture of 50% sand is a good compromise for cohesive and coarse materials. The statistical variations of heavy metal and polycyclic aromatic hydrocarbons from the optimized test with and without sand admixture were determined with an 8-fold intralaboratory and an interlaboratory test. Then the sand admixture was validated for 16 materials (soils, demolition wastes, ashes and other industrial wastes).


Assuntos
Metais Pesados , Hidrocarbonetos Policíclicos Aromáticos , Resíduos Industriais , Solo
3.
Environ Monit Assess ; 192(3): 166, 2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32030517

RESUMO

Gas flaring is a major activity in oil exploration processes in Nigeria with concerns on its effects on the oil communities. This study investigated the contribution of flare gases to pollution burden of Anieze and Okwuibome communities. Water samples were displayed at 10-m, 50-m, and 100-m locations from gas-flaring stations, and control samples were taken in another location. After a month, the water samples were examined for heavy metals, polycyclic aromatic hydrocarbons, and physico-chemical parameters. Pb was found only in the 50-m location and above the WHO standard. Fe, Zn, and Cr were detected in the order 10 m > 50 m > 100 m > control whereas Cd was detected in the order 100 m > 50 m > 10 m > control. Fe, Zn, Cr, and Cd were linked to gas-flaring activities. The total PAHs were found in the order 10 m (1929.43 µg/L) > 100 m (1759.64 µg/L) > 50 m (620.27 µg/L) > control (389.37 µg/L). The signature ratio related the PAH sources to combination of petroleum and combustion sources. The sources of the PAHs were linked to the flare gas. The study implicates gas-flaring activities for the increased pollution burden in the communities and suggests policies that guide its reduction in petroleum explorations.


Assuntos
Água Subterrânea , Metais Pesados , Campos de Petróleo e Gás , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , Gases , Nigéria
4.
J Environ Manage ; 260: 110153, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090843

RESUMO

Bioremediation of polycyclic aromatic hydrocarbons (PAHs) in soil matrix is often arbitrated by the presence of soil organic matter (SOM). The present study focuses on determining the effect of the soil organic content on the mycoremediation of two model PAHs, phenanthrene (Phe) and benzo(a) pyrene (BaP) through microcosm studies. On comparing various microcosm strategies, a maximum degradation of Phe (99%) and BaP (48.5%) in soil bioaugmented with Pleurotus dryinus IBB 903, followed by, biostimulation with the degradation of Phe (89.9%) and BaP (24.8%) were noted. On relating the degradation pattern with lignolytic enzyme cocktail production, a laccase activity of 108 U/Kg at day 21, aryl alcohol oxidase (411 U/Kg) and manganese peroxidase (52.2 U/Kg) at day 14 along with lignin peroxidase (481 U/Kg) at day 21 were noted in fungal augmented soils, which were comparatively higher than levels observed in the bio-stimulation. Investigating the impact of different concentration of SOM (3-12%), a maximum remediation of Phe by 100% at 9% SOM in days 28 and 58.19% for BaP at 12% SOM, respectively was exhibited. Further, the biosorption effect of PAHs in abiotic condition showed a positive correlation with the increase in SOM, with a maximum adsorption of 3.78% Phe, and 6.93% BaP. The results support that the nominal adsorption ability of SOM, and helps in enhancing the microbial growth, thereby improving their degradation potentials, when less than 6% of SOM was utilized. Overall, this work establishes the critical role of organic matter in the soil with reference by simultaneous stimulation and degradation capability in complete PAHs remediation.


Assuntos
Pleurotus , Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Biodegradação Ambiental , Solo , Microbiologia do Solo
5.
Toxicol Lett ; 324: 54-64, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32007588

RESUMO

The aims of this work were to assess the PAH exposure among roofers and to identify relevant biomarkers for monitoring occupational exposure. Several campaigns were conducted between 2004 and 2017, with 28 individual air samples and 240 urinary samples collected from 73 roofers. Seventeen parent PAHs and 14 urinary biomarkers, metabolites of pyrene (1-OHP), benzo(a)pyrene (3-OHBaP and TetraolBaP), naphthalene (1- and 2-naphtols), fluorene (1- 2- 3- 9-fluorenols) and phenanthrene (1- 2- 3- 4- 9-phenanthrols), were analysed. Three exposure groups were considered: soft-applied roofing using polymer-modified bitumen ("PMB"), hot-applied roofing using oxidized bitumen ("OB") and the tearing off of old roof coatings containing coal tar ("CT"). The PAHs containing 2-3 rings were much more abundant, and the highest airborne levels were observed in the "CT" group. The biomonitoring results were consistent with these results, with a large predominance of 2-3 ring PAH metabolites. 1-OHP, 3-fluorenol and 2-phenanthrol were better correlated with airborne levels and less influenced by smoking than the other metabolites. Conversely, 1-/2-naphtol levels were heavily influenced by smoking and not correlated with airborne naphthalene levels. Moreover, 3-OHBaP and TetraolBaP levels were very low when applying bitumen membranes, and much higher exposures were observed during tear-off activities. In this context, the recommended strategy for roofer biomonitoring should include 1-OHP, fluorenols and phenanthrols, as well as carcinogenic BaP metabolites (3-OHBaP or TetraolBaP) when evaluating the occupational exposure of roofers that are tearing off old roof coatings.


Assuntos
/métodos , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/urina , Adulto , Poluentes Ocupacionais do Ar/análise , Benzopirenos/metabolismo , Biomarcadores/urina , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Material Particulado/análise , Pirenos/metabolismo , Adulto Jovem
6.
Mar Pollut Bull ; 151: 110781, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056582

RESUMO

The aim of the present study was to evaluate the presence of polycyclic aromatic hydrocarbons (PAHs) in oysters (Crassostrea rhizophorae) collected from Todos os Santos Bay (Bahia, Brazil). The total PAH concentration was highest in Madre de Deus (36.3 to 37.8 ng g-1 in dry weight, dw), which is located near a petrochemical complex, oil refinery, and commercial port. In the Paraguaçu river estuary, PAH concentrations varied between 23.2 and 25.7 ng g-1 dw. The lowest concentrations (1.55 ng g-1 dw) were found in the Jaguaribe river estuary, which can be considered a relatively preserved area. The main source of PAHs in the study areas was observed to be pyrogenic. Values of benzo[a]pyrene toxic equivalent ranged from 0.28 to 4.20. The concentrations of PAHs in oysters from the Paraguaçu river estuary and in Madre de Deus indicate the possible lifetime risk of developing cancer in humans who feed on it.


Assuntos
Monitoramento Ambiental , Ostreidae/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Baías , Brasil , Sedimentos Geológicos , Humanos , Rios
7.
Mar Pollut Bull ; 151: 110804, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056599

RESUMO

Here, we report results from a 15-day mesocosm experiment examining changes in estimated oil equivalents (EOEs), n-alkanes (n-C10 to n-C35), polycyclic aromatic hydrocarbons (PAHs) and petroleum biomarkers. Water accommodated fractions (WAF) of oil and diluted chemically enhanced WAF (DCEWAF) were prepared and concentrations of oil residues determined on day 0, 3 and 15, respectively. Significant removals of n-alkane and PAHs were observed starting from day 3. The n-C17/pristane and n-C18/phytane ratios suggested that the n-alkane removal was due to biodegradation in the mesocosms. The ratios of C2-dibenzothiophenes/C2-phenanthrenes (D2/P2) and C3-dibenzothiophenes/C3-phenanthrenes (D3/P3) were found to be stable through the experiment. DCEWAF treatment had longer half-lives for most n-alkanes but shorter half-lives for most PAHs than the WAF treatment. Most petroleum biomarkers were stable throughout the experiment. However, depletion of TAS (tricyclic aromatic steroids) was observed on day 15 of DCEWAF treatment.


Assuntos
Ecossistema , Poluição por Petróleo , Petróleo , Tensoativos , Poluentes Químicos da Água , Hidrocarbonetos , Hidrocarbonetos Policíclicos Aromáticos
8.
Mar Pollut Bull ; 151: 110821, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32056614

RESUMO

For decades, in response to industrialization and urbanization, environmental qualities of estuarine and coastal areas of the west coast of Korea have been deteriorating. Long-term changes in concentrations of persistent toxic substances (PTSs) in sediments, including PAHs, styrene oligomers, nonylphenols, and metals and their potential toxicities via AhR- and ER-mediated potencies, and bioluminescent bacterial inhibition, were investigated. Long-term monitoring in five estuarine and coastal areas (2010-2018; 10 sites) showed that concentrations of PAHs and nonylphenols in sediments have declined while concentrations of some metals, Cd, Cr, and Hg have increased. Similarly, AhR-mediated potencies in sediments have declined, but inhibitions of bioluminescent bacteria have increased. Concentrations of sedimentary PAHs and AhR-mediated potencies were significantly (p < 0.01) and positively correlated. Sources of PAHs from combustion have been gradually declining while inputs from vehicle exhaust by-products have been increasing. Overall, this study brought our attention a balanced regulation in chemical-specific manner.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos , República da Coreia , Poluentes Químicos da Água/toxicidade
9.
Chemosphere ; 244: 125537, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32050337

RESUMO

Understanding exposure to air pollution during extreme events such as fire emergencies is critical for assessing their potential health impacts. However, air pollution emergencies often affect places without a network of air quality monitoring and characterising exposure retrospectively is methodologically challenging due to the complex behaviour of smoke and other air pollutants. Here we test the potential of roof cavity (attic) dust to act as a robust household-level exposure proxy, using a major air pollution event associated with a coal mine fire in the Latrobe Valley, Australia, as an illustrative study. To assess the relationship between roof cavity dust composition and mine fire exposure, we analysed the elemental and polycyclic aromatic hydrocarbon composition of roof cavity dust (<150µm) from 39 homes along a gradient of exposure to the mine fire plume. These homes were grouped into 12 zones along this exposure gradient: eight zones across Morwell, where mine fire impacts were greatest, and four in other Latrobe Valley towns at increasing distance from the fire. We identified two elements-barium and magnesium-as 'chemical markers' that show a clear and theoretically grounded relationship with the brown coal mine fire plume exposure. This relationship is robust to the influence of plausible confounders and contrasts with other, non-mine fire related elements, which showed distinct and varied distributional patterns. We conclude that targeted components of roof cavity dust can be a useful empirical marker of household exposure to severe air pollution events and their use could support epidemiological studies by providing spatially-resolved exposure estimates post-event.


Assuntos
Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Poeira/análise , Exposição por Inalação/estatística & dados numéricos , Poluentes Atmosféricos/análise , Austrália , Cidades , Carvão Mineral/análise , Monitoramento Ambiental , Humanos , Mineração , Hidrocarbonetos Policíclicos Aromáticos/análise , Estudos Retrospectivos , Fumaça/análise
10.
Environ Sci Technol ; 54(5): 2922-2930, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32022550

RESUMO

Nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) from the direct atmospheric emission or the degradation of parent PAHs are increasingly recognized because of their potential health risks. Herein, we investigated the effects of four NPAHs/OPAHs (1-NNAP, 9-NANT, 9,10-AQ, and 9-FLU) and their parent PAHs (NAP, ANT, and FLU) on endothelium function with regard to endothelial nitric oxide synthase (eNOS) and endothelium-derived nitric oxide (NO) production in human umbilical vein endothelial cells. The eNOS enzymatic activity and NO production were promoted by NAP, ANT, and FLU; however, eNOS activity was dropped by 52.8, 52.1, 52.5, and 44.5%, and NO production was decreased by 31.1, 50.3, 65.0, and 35.0% after 24 h exposure to 0.01 µM 1-NNAP, 9-NANT, 9,10-AQ, and 9-FLU, respectively. The mRNA expression of eNOS and protein expression of phosphorylated eNOS (Ser1177) were increased by three PAHs but decreased by four NPAHs/OPAHs. The 100 ns molecular dynamics simulations reveal the conformational alteration in the key propionate of heme upon the binding of NPAHs/OPAHs. Our findings provide the first in silico and in vitro evidence for the potential endothelial dysfunction of nitrated and oxygenated PAHs. The health risk implications of NPAHs/OPAHs and corresponding parent PAHs warrant further research.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Células Endoteliais , Monitoramento Ambiental , Humanos , Nitratos , Óxido Nítrico , Óxido Nítrico Sintase Tipo III
11.
Environ Sci Technol ; 54(5): 2843-2850, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036658

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) present in crude oil are known to impair visual development in fish. However, the underlying mechanism of PAH-induced toxicity to the visual system of fish is not understood. Embryonic zebrafish (Danio rerio) at 4 h post fertilization were exposed to weathered crude oil and assessed for visual function using an optokinetic response, with subsequent samples taken for immunohistochemistry and gene expression analysis. Cardiotoxicity was also assessed by measuring the heart rate, stroke volume, and cardiac output, as cardiac performance has been proposed to be a contributing factor to eye-associated malformations following oil exposure. Larvae exposed to the highest concentrations of crude oil (89.8 µg/L) exhibited an increased occurrence of bradycardia, though no changes in stroke volume or cardiac output were observed. However, genes important in eye development and phototransduction were downregulated in oil-exposed larvae, with an increased occurrence of cellular apoptosis, reduced neuronal connection, and reduced optokinetic behavioral response in zebrafish larvae.


Assuntos
Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Apoptose , Peixe-Zebra
12.
Sci Total Environ ; 713: 136428, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019009

RESUMO

This study was designed to evaluate the occurrence and variation in concentrations, sources and cancer risk of PM2.5-bound PAHs. Airborne PM2.5-bound PAHs were sampled during a one-year campaign (2014-2015) in Anshan city, a typical iron and steel city in northeast China. A total of 374 PM2.5 samples were collected. A source-oriented positive matrix factorization (PMF) model and PAH diagnostic ratios were used to investigate the potential sources of PAHs in the atmospheric environment of Anshan, and the lifetime cancer risk of the population associated with PAHs through inhalation exposure was assessed by a PMF-ILCR model. Concentrations of PM2.5 and 16 PAHs ranged from 13.55 µg/m3 to 315.96 µg/m3 and 5.08 ng/m3 to 520.02 ng/m3, respectively. These values were higher in winter. PAH content from stationary sources and biomass combustion was higher than from other sources. Through the coefficient of divergence and localized PAH diagnostic ratio methods, we concluded that PM2.5-bound PAHs in Anshan originated mainly from the following sources: biomass combustion, vehicle emissions, fugitive dust, coking dust and natural gas emissions. Based on the source-oriented PMF model, coal combustion, fugitive dust, vehicle emissions, coking dust, and biomass combustion were the main sources contributing to PM2.5, accounting for 26.3%, 24.6%, 21.9%, 18.0%, and 6.3% of PM2.5, respectively. According to the PMF-ILCR model results, ILCR risks estimated for adults and children were respectively 1.19 × 10-5 and 8.55 × 10-6 in winter, higher than in other seasons, and higher than the threshold value (10-6). Together, vehicle emissions (diesel exhaust and gasoline exhaust), coal combustion and coking dust, contributed to over 86% of the cancer risk associated with PM2.5-bound PAHs exposure in Anshan.


Assuntos
Material Particulado/análise , Poluentes Atmosféricos , China , Cidades , Monitoramento Ambiental , Humanos , Ferro , Hidrocarbonetos Policíclicos Aromáticos , Medição de Risco , Estações do Ano , Aço , Emissões de Veículos
13.
Waste Manag ; 105: 233-239, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-32088569

RESUMO

The EU's publication of the 2017 End-of-Life Vehicle Recycling and Recovery results reported that the UK failed to meet its targets. The Commission's data showed that the UK only achieved a rate of 94.1% falling short of the 95% target. The treatment of automotive shredder residue (ASR) using pyrolysis technologies offers a potential solution to this shortfall. The pyrolysis products could contribute to the target as well as supporting the circular economy package. However, there are questions about their hazardous nature and whether they qualify as secondary products. ASR, from a commercial plant, was processed through a pilot-scale pyrolysis unit, which separated the char into two fractions: coarse ≥0.1 mm and fine ≤0.1 mm. These were chosen as potential commercial products. Chars were produced from two processing temperatures of 800 and 1000 °C. These temperatures maximise gas production and produce the best "quality" char in terms of limiting organic contamination. It was found that the toxicity of the chars changed with both processing temperature and size fraction; with the maximum total PAHs concentration in the fine fraction at 800 °C. The coarse fractions were shown to be non-hazardous. It is suggested that some form of post-separation may be required to remove the hazardous component. The implication was that non-separated char could be classified as hazardous even if its overall characteristics were not, due to the role of dilution. If there were any questions about the status of the char this could prevent the use of ASR to meet the higher ELV target.


Assuntos
Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Automóveis , Pirólise , Reciclagem
14.
J Environ Manage ; 255: 109886, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32063323

RESUMO

The Rhône River (France) has been used for energy production for decades and 21 dams have been built. To avoid problems due to sediment storage, dam flushing operations are periodically organized. The impacts of such operations on suspended particulate matter (SPM) dynamics (resuspension and fluxes) and quality (physico-chemical characteristics and contamination), were investigated during a flushing operation performed in June 2012 on 3 major dams from the Upper Rhône River. The concentrations of major hydrophobic organic contaminants (polychlorinated biphenyls, polycyclic aromatic hydrocarbons - PAHs, bis(2-ethylhexyl)phthalate [DEHP] and 4-n-nonylphenol), trace metal elements, particulate organic carbon (POC) and particle size distribution were measured on SPM samples collected during this event as well as on those obtained from 2011 to 2016 at a permanent monitoring station (150 km downstream). This allows to compare the SPM and contaminant concentrations and fluxes during the 2012 dam flushing operations with those during flood events and baseflow regime. At equal water discharge, mean SPM concentrations during flushing were on average 6-8 times higher than during flood events recorded from 2011 to 2016. While of short duration (19 days), the flushing operations led to the resuspension of SPM and contributed to a third of the mean annual SPM flux. The SPM contamination was generally lower during flushing than during baseflow or flood, probably due to the fact that flushing transports SPM only issued from resuspended sediment, with no autochtonous particles nor eroded soil. The only exception are PAHs and DEHP with higher concentrations during flushing, which must be issued from the resuspension of legacy-contaminated sediments stored behind the dams before the implementation of emission regulations. During flushing, the variations of POC and contaminant concentrations are also mostly driven by particle size. Finally, we propose a list of recommendations for the design of an adequate monitoring network to evaluate the impact of dam flushing operations on large river systems.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Monitoramento Ambiental , França , Sedimentos Geológicos , Rios
15.
Bioresour Technol ; 303: 122947, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32045865

RESUMO

Enhanced macroalgal biochars with large specific surface areas (up to 399 m2 g-1), partly graphitized structure, high nitrogen doping (up to 6.14%), and hydrophobicity were fabricated by co-carbonization of macroaglae, ferric chloride, and zinc chloride. These biochars were used as sorbents for the removal of polycyclic aromatic hydrocarbons from water. The sorption capacity of polycyclic aromatic hydrocarbons onto macroalgal biochars was high (up to 90 mg g-1), and recycling by thermal desorption was practicable. We revealed the physical-dominated multilayer sorption process, based on results from characterization and sorption experiments. Pore filling, mass transfer, π-π stacking, and the partition effect were found to be possible sorption mechanisms. This study suggests that porous graphitized nitrogen-doped biochars may be synthesized from macroalgae with simple one-pot carbonization and display promising applicability for sorption removal of organic pollutants from water.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Alga Marinha , Adsorção , Biota , Carvão Vegetal , Nitrogênio , Porosidade
16.
Environ Monit Assess ; 192(2): 88, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31900672

RESUMO

The formation of an oil-suspended particulate material aggregate (OSA) is one of the weathering processes that occur after the spill of oil in marine environments, responsible for the dispersion of hydrocarbons. Oil and particle aggregates are formed from the interaction between small oil droplets and suspended particulate matter (SPM). In general, SPM are fine particles which may be inorganic minerals or organic particles in the water column. OSAs provide vertical dispersion of oil along the water column depending on the acquired density (buoyancy), and may remain near the surface, water column, or bottom of water bodies. The present study examines the formation of these aggregates through the laboratory simulation of an oil spill in the waters of the São Paulo river estuary. The main objective was to investigate the dispersion of polycyclic aromatic hydrocarbons (PAHs), verifying which estuary characteristics most influenced the formation of OSAs and in addition to determine the regions of probable ecotoxicological impact due to the negative buoyancy of the formed aggregate. The results show that there was greater dispersion to the water column, mainly of lighter PAHs, ranging from 85,804.05 ng g-1 (P11C) to 566,989.84 ng g-1 (P17C). The percentage of dispersed PAH concentration per experimental unit ranged from 9.90% in unit P2 to 75.27% in unit P18. The formation of OSAs was influenced mainly by salinity and chlorophyll a. As the most vulnerable regions, the impacts are one mouth (P2 and P4), one central region (P7, P8, and P10), and one source (P18).


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Clorofila A , Ecotoxicologia , Estuários , Sedimentos Geológicos , Material Particulado/análise , Poluição por Petróleo/análise , Rios , Salinidade
17.
Bioresour Technol ; 301: 122736, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31954284

RESUMO

This work aimed to study the removal of phenanthrene, change of bacterial community and microbial functions through combined photocatalysis and biodegradation under ultraviolet (UV) and visible light illumination. Results showed that phenanthrene removal was enhanced in combined system irradiated by UV and visible light. High-throughput sequencing of 16S rRNA gene manifested that alpha diversity (richness, evenness and diversity) got promoted and data of relative abundance reported that Planococcaceae as the dominant bacteriawas replaced by Pseudomonadaceae, with some other functional bacteria quickly acclimatizing. Difference analysis indicated that top fifteen genera were generally different significantly (p < 0.001) among two distinct samples, particularly for Pseudomonas on relative abundance. Functional features' regulation suggested that the bacterial community not only protected itself well but also participated in degrading phenanthrene. Selecting suitable degrading microbial consortium from natural environment and understanding deeply on performance of bacterial community contribute to assemble effective and directional combined system.


Assuntos
Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos , Bactérias , Biodegradação Ambiental , Consórcios Microbianos , RNA Ribossômico 16S
18.
Chemosphere ; 242: 125299, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31896194

RESUMO

The physicochemical characteristics are different for suspended particles (SPS) with different sizes in rivers. Here, we studied the effect of SPS (1 g L-1) with three different sizes (63-106 µm, 20-63 µm, and <20 µm) on the bioaccumulation of deuterated polycyclic aromatic hydrocarbons (phenanthrene-d10, anthracene-d10, fluoranthene-d10 and pyrene-d10) in zebrafish using passive dosing devices to maintain the freely dissolved concentrations of PAHs-d10 constant in water. The results showed that all the three grain size SPS could be ingested by zebrafish, and there was no significant difference in the amount of ingested SPS among the three grain sizes. The concentrations (lipid-normalized or not) of PAHs-d10 in zebrafish were promoted in the presence of the three different size SPS, and the PAH-d10 concentrations in zebrafish increased with decreasing particle size. Compared with the systems without SPS, the lipid-normalized concentrations of PAHs-d10 increased by 12%-72%, 34%-130%, and 60%-196%, respectively in zebrafish in systems with 63-106 µm, 20-63 µm, and <20 µm of SPS after exposure for 20 h. The stronger effect of SPS with smaller grain sizes was probably due to their lower organic carbon content, lower ratio of black carbon to organic carbon content, smaller particle size, and higher dissolved organic matter contents, which could promote the desorption of PAHs-d10 from ingested SPS and bioaccessibility of PAHs-d10 to zebrafish. This study suggests that in addition to SPS concentration, the suspended particle size should be considered in ecological risk assessment for hydrophobic organic compounds in aquatic environment.


Assuntos
Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , Peixe-Zebra/metabolismo , Animais , Bioacumulação , Sedimentos Geológicos/química , Modelos Teóricos , Tamanho da Partícula , Material Particulado/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes Químicos da Água/química
19.
Environ Sci Technol ; 54(5): 2615-2625, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-31950831

RESUMO

Among the nitrated and oxygenated polycyclic aromatic hydrocarbons (NPAHs and OPAHs) are some of the most hazardous substances to public health, mainly because of their carcinogenicity and oxidative potential. Despite these concerns, the concentrations and fate of NPAHs and OPAHs in the atmospheric environment are largely unknown. Ambient air concentrations of 18 NPAHs, 5 quinones, and 5 other OPAHs were determined at two urban and one regional background sites in central Europe. At one of the urban sites, the total (gas and particulate) concentrations of Σ10OPAHs were 10.0 ± 9.2 ng/m3 in winter and 3.5 ± 1.6 ng/m3 in summer. The gradient to the regional background site exceeded 1 order of magnitude. Σ18NPAH concentrations were typically 1 order of magnitude lower than OPAHs. Among OPAHs, 9-fluorenone and (9,10)-anthraquinone were the most abundant species, accompanied by benzanthrone in winter. (9,10)-Anthraquinone represented two-thirds of quinones. We found that a large fraction of the target substance particulate mass was carried by submicrometer particles. The derived inhalation bioaccessibility in the PM10 size fraction is found to be ≈5% of the total ambient concentration of OPAHs and up to ≈2% for NPAHs. For 9-fluorenone and (9,10)-anthraquinone, up to 86 and 18%, respectively, were found at the rural site. Our results indicate that water solubility could function as a limiting factor for bioaccessibility of inhaled particulate NPAHs and OPAHs, without considerable effect of surfactant lipids and proteins in the lung lining fluid.


Assuntos
Poluentes Atmosféricos , Hidrocarbonetos Policíclicos Aromáticos , Monitoramento Ambiental , Europa (Continente) , Humanos , Nitratos , Material Particulado
20.
Environ Sci Process Impacts ; 22(2): 239-255, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-31916559

RESUMO

A bibliometric analysis of published papers with the key words "positive matrix factorization" and "source apportionment" in 'Web of Science', reveals that more than 1000 papers are associated with this research and that approximately 50% of these were produced in Asia. As a receptor-based model, positive matrix factorization (PMF) has been widely used for source apportionment of various environmental pollutants, such as persistent organic pollutants (POPs), heavy metals, volatile organic compounds (VOCs) as well as inorganic cations and anions in the last decade. In this review, based on the papers mainly from 2008 to 2018 that focused on source apportionment of pollutants in different environmental media, we provide a comparison and summary of the source categories of typical environmental pollutants, with a special focus on polycyclic aromatic hydrocarbons (PAHs), apportioned using PMF. Based on the statistical average, coal combustion and vehicular emission, are shown to be the two most common sources of PAHs, and contribute much more to emissions than other sources, such as biomass burning, biogenic sources and waste incineration. Heavy metals were mainly from agricultural activities, industrial and vehicular emissions and mining activities. Quantitative source apportionment on pollutants such as VOCs and particulate matter were also apportioned, showing a prominent contribution from fossil-fuel combustion. We conclude that, aside from natural sources, abatement strategies should be focused on changes in energy structure and industrial activities, especially in China. Source apportionment of typical POPs including polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs), halogenated flame retardants (HFRs) and perfluorinated compounds (PFCs) is less comprehensive and further study is required.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Dibenzodioxinas Policloradas , Hidrocarbonetos Policíclicos Aromáticos , Ásia , China , Dibenzofuranos , Monitoramento Ambiental
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