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1.
Sci Total Environ ; 750: 141202, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32853929

RESUMO

Pollution from heavy metals in urban environments is a topic of growing concern because many metals, including Pb and Cr, are a human health hazard. Exposure to Pb and Cr has been linked to the inhibition of neurological development as well as toxic effects on many organs. Yellow traffic paint (YTP) is a mixture that contains organic polymers, binders, and pigments, which in some cases consist of crocoite (PbCrO4) that may be coated by silica. The primary aim of this study was to investigate the behavior of the crocoite pigment grains within YTP and their silica coatings in simulated environmental and human body conditions. To do this, both YTP and asphalt were collected in Philadelphia, PA, USA. These samples as well as a standard PbCrO4 were investigated with powder X-ray diffraction, X-ray fluorescence, environmental scanning electron microscopy (ESEM), transmission electron microscopy, and energy-dispersive X-ray spectroscopy. Using this multi-analytical approach, mineral phases were determined in the YTP, their shape, dimensional distributions, crystallinity, and chemical composition, as well as elemental distributions before and after experimental interactions. Three batch dissolution experiments with YTP, asphalt, and standard PbCrO4 were performed to simulate ingestion, inhalation, and environmental interaction with rainwater. Elemental releases were determined with inductively coupled plasma-optical emission spectrometry, and results indicated that little (ingestion) to no (environmental and inhalation) Pb and Cr were leached from the YTP during the three experimental procedures. This is likely due to the silica coating that encapsulates the crocoite particles, which persisted during all interactions. The ESEM results for YTP showed dimensional reductions after interactions with all three fluids. The silica coating must be further explored to determine how it breaks down in real environmental conditions.


Assuntos
Metais Pesados , Pintura , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Dióxido de Silício , Espectrometria por Raios X
2.
Chemosphere ; 262: 127843, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32777614

RESUMO

This study aimed to estimate the impact of an abandoned copper (Cu) mine on ecosystem environmental quality, using integrated ecological and biogeochemical analyses. Through a controlled experiment, the amount of Cu released by waste rocks, Cu adsorbed in soils, Cu geochemical behaviour and its leached amount were measured. Furthermore, to investigate the impacts of mine drainage on the adjacent ecosystem, samples of sediments, water and aquatic macroinvertebrates were analysed. We found that waste rocks still have high Cu concentration even after 30 years under weathering, ranging from 7782 to 8717 mg kg-1, associated mainly with carbonates, amorphous oxides and sulphides. It was estimated that 7.2 tonnes of Cu were released by waste rocks into the environment over last 30 years. The concentration of Cu observed in Ubari stream water was (


Assuntos
Cobre/análise , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Brasil , Ecossistema , Poluição Ambiental/análise , Metais/análise , Mineração , Rios , Solo , Poluentes do Solo/análise , Sulfetos/análise
3.
J Environ Manage ; 277: 110999, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32977174

RESUMO

The production and trade activities of global value chains (GVC) increasingly contribute to the gross domestic product (GDP) of developing countries. However, while the development of domestic economies brings about technological progress, it also may have negative consequences such as environmental pollution. Technological progress can be conducive to reducing pollution emissions. Our motive is to realize the dual effects of technological progress and energy saving and emission reduction in developing countries' participation in the global value chain through research on GVC, technological progress and environmental pollution. Improving environmental quality through technological advances and reducing the adverse effects of inequality in trade status, enabling developing countries to obtain dividends from participating in the value chain as much as possible, and mitigating the adverse effects of environmental pollution during development. And lay the policy foundation for developing countries to go green. However, most of the current researches focus on the relationship between GVC and technological progress or GVC and environmental pollution, and the research on the relationship between the three is scarce. We use the WIOD database to try to find the relationship between developing country global value chain participation, technological progress and environmental pollution. Wang's method for GVC embedding is adopted for empirical research on input and output, energy utilization, high-skilled labor ratio, and pollution emissions in five typical developing countries, namely, Brazil, Russia, India, China, and Mexico. The relationships among the degree of participation in GVC, technological progress, and environmental pollution is studied from the perspective of industries in each country. The outcomes indicate that there is a value chain threshold in developing countries. When the degree of participation in a value chain is lower than the threshold, technological progress can result in an increase in pollution; otherwise, technological progress can reduce emissions. These results provide a theoretical basis and practical suggestions for developing countries to realize their own energy conservation, emission reductions, and green development while participating in globalized value chains. However, because the data related to the WIOD database is limited to 1995-2009, there are a few flaws in data integrity, which is also a challenge we face.


Assuntos
Países em Desenvolvimento , Poluição Ambiental , Brasil , Dióxido de Carbono/análise , China , Poluição Ambiental/análise , Índia , México , Federação Russa , Fatores Socioeconômicos
4.
J Environ Manage ; 277: 111481, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33039701

RESUMO

Most heavy metal exposure and pollution results from multiple industrial activities, including metal processing in refineries, and microelectronics. These issues pose a great threat to human health, ecological balance, and even societal stability. During 2012-2017, China, in particular, faced the challenge of 23 heavy metals accidents, six of which were extraordinarily serious accidents. Accidental environmental pollution is rarely caused by a single heavy metal, but rather by heavy metal mixtures. To address the need for a joint exposure risk assessment for heavy metal mixed pollution accidents at the watershed scale, a Copula-based exposure risk dynamic simulation model was proposed. A coupled hydrodynamic and accidental heavy metal exposure model is constructed for an hourly simulation of the exposure fate of heavy metals from each risk source once accidental leakage has occurred. The Copula analysis was introduced to calculate the dual heavy metal joint exposure probability in real time. This method was applied to an acute Cr6+-Hg2+ joint exposure risk assessment for 43 electroplating plants in nine sub-watersheds within the Dongjiang River downstream basin. The results indicated seven risk sources (i.e., S1, S4, H18, H23, H27-H28, and H34) that presented relatively high exposure risk to their surrounding sub-watersheds. Spatially, the acute exposure risk level was highest in the tributary basin (sub-watershed XW) than in the mainstream (sub-watershed DW2) and the river network (sub-watershed RW) of the lower reaches of the Dongjiang River. This research highlights an effective probabilistic approach for performing a joint exposure risk analysis of heavy metal mixed pollution accidents at the watershed scale.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Acidentes , China , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Medição de Risco , Poluentes Químicos da Água/análise
5.
Huan Jing Ke Xue ; 41(8): 3556-3562, 2020 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124328

RESUMO

Surface dust samples were collected from university campuses in Xi'an, and X-ray fluorescent spectrometry was used to determine the contents of nine heavy metals (Mn, As, Pb, Cr, Co, Ni, Cu, V, and Zn). Enrichment factors were subsequently used to determine the enrichment degree of each element and the preliminary determination of the pollution sources. The R programming language and SPSS were used for cluster analysis and principal components analysis to identify the pollution sources. The results showed that the average concentrations of all nine heavy metal elements were higher than their surface soil background values in Shaanxi Province; however, Mn, Co, As, V, and Ni exhibited relatively little enrichment and were less affected by human interference. Cr and Cu were moderately enriched, whereas Zn and Pb were significantly enriched, and human activities played a major role in the enrichment of these four elements. The main sources of Mn, Co, As, V, and Ni in surface dust samples from the university campuses were natural sources, whereas the accumulation of Zn, Cr, and Pb were mainly due to traffic sources, and Cu originated both from the auto repair industry and from paint coatings.


Assuntos
Metais Pesados , Poluentes do Solo , China , Poeira/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , Universidades
6.
Huan Jing Ke Xue ; 41(10): 4749-4756, 2020 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124409

RESUMO

To investigate the impact of mining activities and geological background on the soil environment, 156 soil samples were collected from an agricultural land in southern Youyang County, Chongqing. The content and pH of heavy metals in the soil were analyzed, and the Nemerow index method was used to evaluate the pollution status of soil heavy metals. The source of soil heavy metals was discussed using the principal component analysis/absolute principal component score (PCA/APCS) receptor model. The results showed that the soil Cd pollution was distributed in a planar shape, while soil Hg mainly appeared as point pollution. The medium-severe soil pollution was mainly distributed at the junction of Tushi Town, Mawang Town, and Longtan Town, where the soil was predominantly acidic and there was a higher risk of crop contamination; the indicator Kriging evaluation results showed that there was a higher probability of soil contamination at the junction of the three towns and the northern part of Tushi Township. The results of the PCA/APCS receptor model analysis showed that the sources of soil As, Cd, Cr, and Ni were mainly controlled by geological background; soil Hg, Pb, and Zn were mainly controlled by mining activities; further, soil Cu was affected by both geological background and mining activities. In addition, the agricultural activities were also one of the sources of soil As, Cd, Pb, Cu, and Zn. The medium-heavy pollution of the soil in the study area was mainly caused by mining activities, while the heavy metal pollution of the soil caused by geological background was mainly light pollution. This study can provide a theoretical basis for the safe use of land and the prevention and control of soil pollution in typical regions.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Poluição Ambiental/análise , Fazendas , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
7.
Fa Yi Xue Za Zhi ; 36(4): 437-444, 2020 Aug.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33047522

RESUMO

Abstract: With the growing attention on ecological environment problems and gradual realization of ecological environment value, environmental damage has jumped from administrative penalty to a new stage, judicial penalty, and environmental damage appraisal has provided a legal weapon to safeguard ecological security. As a new forensic category of China with high comprehensiveness and technical difficulty, environmental damage appraisal involves diversified and complex subjects, fields and appraisal objects, and is still in an early stage in terms of theory and practice. This study aims to provide an important reference for the improvement of the Chinese environmental damage appraisal system of environmental damage by summarizing advanced international experience in areas such as laws and regulations, working mechanism and technical system, and putting forward targeted countermeasures and suggestions based on the problems existing in the development and practice of environmental damage appraisal in China.


Assuntos
Meio Ambiente , Poluição Ambiental , China , Poluição Ambiental/análise , Medicina Legal , Humanos
8.
Chemosphere ; 261: 128078, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113667

RESUMO

Per- and polyfluoroalkyl substances (PFAS) are used in a wide variety of consumer products, including ski waxes, and are widespread persistent and hazardous environmental contaminants. We examined the environmental impact of ski wax use at an outdoor recreation area with significant cross-country ski activity by measuring PFAS levels in melted snow, soil and water following a collegiate ski race. We found extremely high levels of long- and short-chain PFAS (C4-C14) contamination in snow at the race start line (∑[PFAS] 7600-10,700 ng/L), with the longer-chain analytes (C10-C14) predominating. The complement of 14 PFAS detected in snow matched what has been found in ski wax. This snow contamination was greatly reduced at a point 3.9 km into the race. Soil at the start line contained the four most predominant PFAS in snow at a mean individual concentration of 2.81 ng/g dry weight. Control soil contained only perfluorooctane sulfonic acid (PFOS), not found in other soil samples, at a concentration of 2.80 ng/g. Shallow groundwater from an on-site well contained only the shorter-chain PFAS (C4-C8), with a mean individual concentration of 4.95 ng/L. Our results suggest that ski wax use, from which fluorocarbons abrade at very high levels onto snow during a ski race, are the main source of PFAS contamination at our site. Regulation of ski wax use is warranted to reduce PFAS pollution.


Assuntos
Ácidos Alcanossulfônicos/análise , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Fluorcarbonetos/análise , Lubrificantes/química , Poluentes Químicos da Água/análise , Água Subterrânea/química , Maine , Esqui , Neve/química , Solo/química , Ceras
9.
Bull Environ Contam Toxicol ; 105(5): 758-763, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33068117

RESUMO

Cenotes are naturally occurring flooded caves that are frequent in Mexico's Yucatan Peninsula; they result from the collapse of limestone bedrock into the regional groundwater table. Cenotes in Quintana Roo are important ecological and economic hot spots but are susceptible to anthropogenic pollution. In this study, we collected water samples from 11 cenotes over multiple years to evaluate polycyclic aromatic hydrocarbon (PAH) concentrations and patterns as associated with tourist traffic. The primary PAHs detected in samples included fluoranthene, anthracene, phenanthrene and naphthalene, with total PAH concentrations increasing almost fivefold for cenotes sampled from 2016 to 2017. This is compared to only a 7% increase in tourist traffic during these years. Multivariate statistical analysis of the PAH concentration data suggests that diesel, gasoline and asphalt are the most likely pollution sources and that they are associated with periods of increased tourist traffic.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Água Subterrânea/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Região do Caribe , México , Análise de Componente Principal
10.
Bull Environ Contam Toxicol ; 105(5): 685-691, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33067667

RESUMO

Owls are predators that perform important ecological functions. There are several threats to owl conservation such as the bioaccumulation of chemicals through environmental contamination. The high probability of bioaccumulation in these animals is related to their role as predators and high trophic positions. The objective of this study was to quantify four elements (cadmium, chromium, nickel, and lead) as the biomarkers of environmental exposure in owls. To this end, we analyzed pellets and feathers of different owl species. These matrices were contaminated with all four elements, with chromium most commonly detected. Chromium and nickel were found in the pellets in all 10 months of the study, and May was the month with the highest concentrations of all the elements. Tyto furcata appears to bioaccumulate more elements in its feathers than Megascops spp. and Athene cunicularia. Our findings showed bioaccumulation of these four elements in owls and their environment.


Assuntos
Monitoramento Biológico/métodos , Poluição Ambiental/análise , Plumas/química , Conteúdo Gastrointestinal/química , Metais Pesados/análise , Estrigiformes/crescimento & desenvolvimento , Animais , Cádmio/análise , Cromo/análise , Refluxo Laringofaríngeo , Chumbo/análise , Metais Pesados/metabolismo , Níquel/análise
12.
PLoS One ; 15(9): e0239006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960903

RESUMO

To prevent and control non-point source pollution, many policies have been carried out by government in China. However, the effectiveness of these policies has rarely been evaluated. In this study, the potential and spatial distribution of agricultural non-point source pollution in the Baiyangdian Basin are reported. This investigation considers multiple parameters under various policies with county as a basic unit. The results for the potential pollution from chemical oxygen demand (COD), ammonia nitrogen (NH3-N), total nitrogen (TN) and total phosphorus (TP) are 60.89×104, 3.93×104, 87.05×104 and 15.10×104 Mg, with corresponding intensities of 190, 12, 272 and 47 kg ha-1 for the Baiyangdian Basin in 2016. The highest pollution from COD is attributed to livestock and poultry breeding, whereas TN and TP are dominantly produced by rural domestic sources, and NH3-N is mostly derived from planting. Spatially, distribution of the counties producing larger non-point source pollution presented a northeast to southwest direction, consistent with the Taihang mountain alignment in the basin. The counties with high pollution intensities are mostly in the south and east of the basin. Agricultural non-point source pollution control and prevention policies contributed in pollution reduction. Compared with 2016, the total potential pollution of COD, NH3-N, TN and TP in 2020 decrease by 45.1%, 14.7%, 37.9% and 37.4%, respectively, whereas for an assumed future time (F2), the decreases are 59%, 51.4%, 56.2% and 55.7%, respectively. Prevention measures should focus on reducing pollution from livestock and poultry breeding as well as planting.


Assuntos
Monitoramento Ambiental/métodos , Poluição Difusa/análise , Poluição Difusa/economia , Agricultura , Amônia/análise , Animais , Análise da Demanda Biológica de Oxigênio/métodos , China , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/tendências , Política Ambiental/tendências , Poluição Ambiental/análise , Poluição Ambiental/economia , Gado , Nitrogênio/análise , Fósforo/análise , Aves Domésticas , Rios , Poluentes Químicos da Água/análise
13.
Chemosphere ; 254: 126852, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957277

RESUMO

This study reports the environmental fate and ecological hazard of the three heavy metals (HMs), viz. copper (Cu), manganese (Mn) and zinc (Zn) in soil influenced by municipal solid waste (MSW) dumping. The experimental site is situated in the vicinity of Deepor Beel, a Ramsar site located in Guwahati, India. This study assessed (i) the distribution pattern of Cu, Mn and Zn in six geochemical fractionations; (ii) the mobility, bioavailability and toxicity of Cu, Mn and Zn based on eight contamination and ecological indices, and (iii) the impact of Cu, Mn and Zn on soil quality. Altogether, 18 soil samples were collected and analysed from the study site using stratified random sampling. Pollution indices and multivariate statistics were applied on the data to identify the level and source of analysed HMs. Sequential extraction has revealed that the binding strength of Cu, Mn and Zn had a uniform trend. Mobility and potential bioavailability of studied HMs were in the order Mn > Cu > Zn. Analysed HMs were dominantly associated with non-bioavailable fractions. The observed low values of various contamination factors indicated the lesser contamination load posed by these metals. Conversely, their high enrichment factor and geo-accumulation index values indicated the sources of these metals were anthropogenic. Overall, the pollution and ecological indices registered lower contamination. Yet, it would be prudent to adopt efficient MSW management strategies for eliminating any future risk emanating out of this dumping site and posing threat to nearby Deepor Beel and its associated flora and fauna.


Assuntos
Metais Pesados/análise , Medição de Risco , Poluentes do Solo/análise , Cobre/análise , Monitoramento Ambiental , Poluição Ambiental/análise , Índia , Manganês/análise , Zinco/análise
14.
Chemosphere ; 254: 126854, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957278

RESUMO

Surfactant-enhanced remediation (SER) is an efficient and low-cost technology for polycyclic aromatic hydrocarbons (PAHs) contaminated sites. This study assessed the desorption processes and effects of Heterogemini surfactant (Dodecyldimethylammonium bromide/tetradecyldimethylammonium bromide, DBTB), two traditional surfactants (Hexadecyl trimethyl ammonium bromide, CTAB; Sorbitan monolaurate, Span 20) and their mixed systems on the real PAHs-contaminated soil from an abandoned coking plant, as well they were analyzed micro morphologically. DBTB had greater desorption capability for PAHs and favorable interaction with the traditional surfactants confirmed by reaction parameters ßm and Gibbs. Whether for total PAHs (TPAHs) or different molecular weight PAHs, the mixed system Span 20/DBTB had larger molar solubilization ratio (MSR) and partition coefficient (Km) than CTAB/DBTB, the highest desorption rate for TPAHs reaching 68.83%. Additionally, microscopic morphology showed micelles of Span 20/DBTB were more dispersed and formed strings easily, explaining its good desorption capability. What resulted demonstrated the feasibility of DBTB, a novel Heterogemini surfactant, and its mixed systems remediating PAHs-contaminated soil of abandoned industrial site.


Assuntos
Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Tensoativos/química , Adsorção , Coque/efeitos adversos , Poluição Ambiental/análise , Micelas , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solubilidade
15.
PLoS One ; 15(9): e0238870, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32941472

RESUMO

Monitoring the ecological impacts of environmental pollution and the effectiveness of remediation efforts requires identifying relationships between contaminants and the disruption of biological processes in populations, communities, or ecosystems. Wildlife are useful bioindicators, but traditional comparative experimental approaches rely on a staunch and typically unverifiable assumption that, in the absence of contaminants, reference and contaminated sites would support the same densities of bioindicators, thereby inferring direct causation from indirect data. We demonstrate the utility of spatial capture-recapture (SCR) models for overcoming these issues, testing if community density of common small mammal bioindicators was directly influenced by soil chemical concentrations. By modeling density as an inhomogeneous Poisson point process, we found evidence for an inverse spatial relationship between Peromyscus density and soil mercury concentrations, but not other chemicals, such as polychlorinated biphenyls, at a site formerly occupied by a nuclear reactor. Although the coefficient point estimate supported Peromyscus density being lower where mercury concentrations were higher (ß = -0.44), the 95% confidence interval overlapped zero, suggesting no effect was also compatible with our data. Estimated density from the most parsimonious model (2.88 mice/ha; 95% CI = 1.63-5.08), which did not support a density-chemical relationship, was within the range of reported densities for Peromyscus that did not inhabit contaminated sites elsewhere. Environmental pollution remains a global threat to biodiversity and ecosystem and human health, and our study provides an illustrative example of the utility of SCR models for investigating the effects that chemicals may have on wildlife bioindicator populations and communities.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Biomarcadores Ambientais , Mamíferos/fisiologia , Modelos Biológicos , Poluentes do Solo/análise , Solo/química , Distribuição Animal , Animais , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Ecossistema , Poluição Ambiental/análise , Recuperação e Remediação Ambiental , Feminino , Masculino , Camundongos , Densidade Demográfica , Poluentes do Solo/farmacologia , Análise Espacial
16.
J Environ Manage ; 276: 111371, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32947118

RESUMO

China's export trade has been expanding steadily in recent years, significantly increasing resource consumption and environmental pollution. High- and new-technology industries are essential for achieving sustainable economic development and improving environmental quality. This study employs a multi-regional input-output model to estimate the economic benefits and environmental costs of export trade in high- and new-technology industries. Then, it analyzes the impact of economic benefits and technological levels on environmental pollution using the Stochastic Impacts by Regression on Population, Affluence, and Technology model. An input-output multi-objective linear programming model and a non-dominated sorting genetic algorithm II are adopted to combine economic development with environmental pollution and determine the optimal path for export trade. The results show that technological progress in China's high- and new-technology industries is conducive to reducing embodied carbon emissions in developed countries while increasing emissions in developing countries. Moreover, a nonlinear three-stage accompanying relationship exists between the economic benefits and environmental costs of high- and new-technology exports; this is because exports with low economic benefits generate fewer carbon emissions whereas exports with high economic benefits generate significant carbon emissions. An increase in exports with ultra-high economic benefits will generate excessive embodied carbon emissions that hinder coordinated economic-environmental development. Lastly, technological progress in the electrical and optical equipment sector can effectively promote pollution reduction; thus, it should be further developed to improve the comprehensive benefits of exports.


Assuntos
Carbono , Poluição Ambiental , Dióxido de Carbono/análise , China , Desenvolvimento Econômico , Poluição Ambiental/análise , Indústrias
17.
Bull Environ Contam Toxicol ; 105(3): 446-452, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32894322

RESUMO

Increasing contamination of urban soil by persistent organic pollutants is a major environmental issue. The purpose of the present study was to investigate the distribution, source and human health risk of polycyclic aromatic hydrocarbons (PAHs) in different functional areas in Zhengzhou City, China. Total 130 soil samples were collected from surface layer (0-10 cm) in urban road, overpass, residential area and park in the city during January 2019. Concentrations of ∑PAH16 in the urban soil ranged from 49.90 to 11,565 µg kg-1 and seven carcinogenic PAHs accounted for 69% of the total PAHs. The mean concentrations of PAHs decreased in the following order: urban road > overpass > residential area > park. Analysis based on diagnostic rate demonstrated that PAHs mainly originated from pyrolysis sources including traffic emissions and combustion of coal and biomass. Health risk assessment indicated that PAHs in urban road in the city have potential carcinogenic risks to residents. The present study suggested that the control of urban PAHs pollution in Zhengzhou City should be strengthened.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Biomassa , Carcinógenos/análise , China , Cidades , Carvão Mineral/análise , Poluição Ambiental/análise , Humanos , Medição de Risco , Solo
18.
Chemosphere ; 258: 127310, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947673

RESUMO

We characterized the aerosol composition and sources of particulate matter (PM) in Sanmenxia, a polluted city located in the Fen-Wei Plain region of Central China. The PM2.5 concentration decreased by 18% from 72 µg m-3 in 2014 to 59 µg m-3 in 2019. All chemical species presented pronounced seasonal variations, with their highest concentrations in winter due to enhanced emissions and the frequent stagnant meteorological conditions. Nitrate was the major fraction of PM2.5 during all seasons (35-41%) except summer (25%), while sulfate was a dominant species in summer (29%) compared to other seasons (16-18%) from July 2018 to June 2019. The detailed analysis of a wintertime severe haze episode that lasted for approximately half a month demonstrated that secondary aerosols, including secondary organic aerosol, sulfate, nitrate, and ammonium, contributed 89% to non-refractory PM1 (NR-PM1), indicating the remarkable role of secondary aerosol formation in air pollution in Sanmenxia. Positive matrix factorization analysis further showed considerably enhanced low-volatility oxygenated organic aerosol (OA) and hydrocarbon-like OA during severe haze episodes, while significant contributions in semi-volatile oxygenated OA and coal combustion OA during clean periods. Severe pollution events in the city were generally associated with air masses from the southwest, and we also found that aerosol species, especially secondary aerosol species, showed distinct forenoon increases that were caused by the subsidence of air pollutants aloft. Our results highlight that future air quality improvement would benefit substantially from a more efficient control of gaseous precursors, particularly the NOx emissions from industry and vehicle emissions.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , China , Cidades , Carvão Mineral/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Poluição Ambiental/análise , Hidrocarbonetos/química , Nitratos/análise , Óxidos de Nitrogênio/análise , Material Particulado/análise , Estações do Ano , Emissões de Veículos/análise
19.
Chemosphere ; 254: 126799, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32957268

RESUMO

Enrichment of cadmium (Cd) during weathering and pedogenesis of carbonate rocks has resulted in large areas of lands with soil Cd concentrations exceeding the official guidelines in China and other countries. However, it is reported in many studies that the risk of soil contamination by Cd from this natural process can be neglected as most of the Cd is not bioavailable. Noticing that the previous studies focused only on eluvial areas but not on lowland alluvium, where Cd from the eluvial areas can be transported and accumulated, we selected the Qingyang county in Anhui province, where there are two small drainage basins developed wholly on carbonate bedrock, to compare the Cd speciation and activity between eluvium and alluvium, and to evaluate the risk of Cd pollution to the latter. By the application of systematic sampling and analysis of the bedrock, soil, and rice grain samples, and in comparison with the previously acknowledged "high background with low mobility" area in Guizhou, it was found that soil developed from alluvium has both higher total Cd and higher mobile Cd proportion than soil from the upland eluvium. A very high percentage of rice grain samples (51%) grown on the alluvial soil exceeded the food standard for Cd (0.2 mg kg-1). Therefore, the spatial division of alluvium and eluvium should be the first step in the assessment of the Cd risk in carbonate regions, and special attention should be given to soil developed from alluvium.


Assuntos
Cádmio/análise , Poluentes do Solo/análise , Carbonatos/análise , China , Poluição Ambiental/análise , Poluição Ambiental/estatística & dados numéricos , Oryza , Solo , Tempo (Meteorologia)
20.
Environ Pollut ; 265(Pt B): 115029, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32806453

RESUMO

Environmental complexity leads to differences in the spatial distribution of heavy metal pollution in soil and rice. Such spatial differences will seriously affect the safety of planted rice and can impact regional management and control. How to scientifically reveal these spatial differences is an urgent problem. In this study, the spatial mismatch relationship between Cd pollution in soil and rice grains (brown rice) was first explored by the interpolation method. To further reveal the causes of these, the specific recognition rules of the spatial relationship of Cd pollution were extracted based on a decision tree model, and the results were mapped. The results revealed a spatial mismatch in Cd pollution between the soil and rice grains in the study area, and the main results are as follows: (i) slight soil pollution and safe rice accounted for 68.88% of the area; (ii) slight soil pollution and serious rice pollution accounted for 13.39% of the area and (iii) safe soil and serious rice pollution accounted for 11.63% of the area. In addition, 11 recognition rules of Cd spatial pollution relationship between soil and rice were proposed, and the main environmental factors were determined: SOM (soil organic matter), Dis-residence (distance from residential area), soil pH and LAI (leaf area index). The average accuracy of rule recognition was 75.90%. The study reveals the spatial mismatch of heavy metal pollution in soil and crops, providing decision-making references for the spatial accurate identification and targeted prevention of heavy metal pollution spaces.


Assuntos
Oryza , Poluentes do Solo/análise , Cádmio/análise , Árvores de Decisões , Monitoramento Ambiental , Poluição Ambiental/análise , Solo
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