Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Appl Radiat Isot ; 206: 111252, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38422941

RESUMO

This study analyzed 16070 daily and 608 weekly air filter samples from the Helsinki metropolitan area collected between 1962 and 2005. The aim was to use the Potential Source Contribution Function (PSCF) to determine potential sources of silicon (Si), zinc (Zn), lead (Pb), and radioactive isotope 210Pb. The main sources for Si and Pb were industrial activities, particularly mining, metal industry, and traffic. Common source areas for Zn and 210Pb were identified in the eastern and southeastern parts of the measuring site.

2.
Chemosphere ; 343: 140242, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37739135

RESUMO

There is accumulating evidence of the toxicity of organic ultraviolet absorbers (OUVAs); however, limited information is available regarding the presence of OUVAs in terrestrial environments and organisms. Therefore, this study was conducted to investigate the occurrence of 11 OUVAs in soils and typical plant species from an industrial metropolis in China. Total OUVA concentrations in soils ranged from 1.30 to 80.3 ng g-1 DW. Based on comparison with previously reported data, OUVA contamination in soil was not severe. Benzophenone and octocrylene were the dominant OUVAs in soils, with median contributions to total concentrations of 25% and 15%, respectively. Source assessment revealed that the observed OUVA contamination primarily originated from industrial activities and the use of personal care products. The concentration of 11 OUVAs in plants ranged from 159 to 4470 ng g-1 DW, at high levels. Our findings imply that great attention should be given to the presence of these chemicals in plants because of the risk they could pose as well as the potential for biomagnification as plants are eaten by insects and birds. Our results also indicate the necessity to further study the geochemical behavior of these chemicals in urban ecosystems in order to better manage the harmfulness to terrestrial ecological health caused by their exposure through the food chains.

3.
FEMS Microbiol Lett ; 3702023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-37401172

RESUMO

Despite the important roles that marine sponges play in ecosystem functioning and structuring, little is known about how the sponge holobiont responds to local anthropogenic impacts. Here we assess the influence of an impacted environment (Praia Preta) on the microbial community associated with the endemic sponge Aplysina caissara in comparison to a less-impacted area (Praia do Guaecá) from the coast of São Paulo state (Brazil, southwestern Atlantic coast). We hypothesized that the local anthropogenic impacts will change the microbiome of A. caissara and that the community assembly will be driven by a different process (i.e. deterministic versus stochastic) under distinct levels of impact. The microbiome at the amplicon sequence variants level was found to be statistically distinct between sponges from the different sites, and this was also seen for the microbial communities of the surrounding seawater and sediments. Microbial communities of A. caissara from both sites were found to be assembled by deterministic processes, even though the sites presented distinct anthropogenic impacts, showing a pivotal role of the sponge host in selecting its own microbiome. Overall, this study revealed that local anthropogenic impacts altered the microbiome of A. caissara; however, assembly processes are largely determined by the sponge host.


Assuntos
Efeitos Antropogênicos , Biodiversidade , Microbiota , Poríferos , Animais , Brasil , Microbiota/genética , Filogenia , Poríferos/microbiologia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Sedimentos Geológicos/microbiologia , Interações entre Hospedeiro e Microrganismos , Archaea/classificação , Archaea/genética , Bactérias/classificação , Bactérias/genética
4.
Environ Pollut ; 318: 120768, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36473643

RESUMO

This study provides the first data on the distribution, sources, and transport dynamics of polycyclic aromatic hydrocarbons (PAHs) in Fildes Peninsula, Antarctica via summertime analyses of lakes, seawater, snow, and air in 2013. Relatively high PAH levels and similar composition profiles (dominance of two- and three-ring PAHs) in the investigated marine and terrestrial environmental matrices were found, indicating substantial primary emissions of petrogenic PAHs. This result was corroborated by nonequilibrium partitioning of atmospheric PAHs caused by release of anthropically-derived lighter PAHs and air mass movement trajectories mainly originated from the Antarctic marginal seas. Notable geographical disparities of PAH pollution in the various types of samples consistently suggested impacts of station-related activities, rather than long-range atmospheric transport, on PAHs in Fildes Peninsula. The lack for temperature dependence for gas-phase concentrations and various molecular diagnostic ratios of atmospheric PAHs demonstrated that the impact of local anthropogenic inputs on air PAH variability supersedes the re-emission effect. The derived air-water and air-snow exchanges of PAHs in this remote region indicated a disequilibrium state, partially associated with intense local emissions of PAHs. PAH outgassing from, and absorption into, lake and marine waters were both observed, probably due to differences in anthropogenic influences among sites, while the net deposition of gaseous PAHs into snow prevailed. The results of this study shed lights on the major importance of native anthropogenic sources in the footprint and fate of PAHs in the Fildes Peninsula, which merits further monitoring.


Assuntos
Poluentes Atmosféricos , Poluição Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Poluentes da Água , Poluentes Atmosféricos/análise , Regiões Antárticas , Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Água do Mar/análise , Poluentes da Água/análise
5.
Front Psychol ; 13: 886114, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35519634

RESUMO

Buddhism and Taoism are among two of the major religions in China. Their "Tian-ren-he-yi" belief system promotes a conception of harmony between man and nature, which is an important guide for the construction of ecological civilization in China. Using data from Chinese listed manufacturing companies, this paper explores the impact and mechanism of Chinese local religious beliefs on corporate environmental governance. The results indicate that this belief system can improve corporate environmental performance. Furthermore, mechanism tests show that the "Tian-ren-he-yi" belief system promotes corporate environmental practices by reducing the pressure on management to achieve economic performance goals and increasing investment in environmental protection. Finally, the impact of the belief system on corporate environmental performance is more efficacious when the enterprises are under weak external supervision. Our results imply that the traditional religious culture is an important factor that influences corporate environmental performance in Chinese business practices.

6.
Environ Sci Pollut Res Int ; 29(11): 16233-16249, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34642887

RESUMO

Particulate matter is usually regarded as the dominant pollutant in Tehran megacity in Iran. However, the number of ozone exceedance days significantly increased in recent years. This study analyzes simultaneous measurements of O3 and NOx (NO+NO2) concentrations to improve our understanding of ozone evolution during the summers of 2017 to 2019. The k-means clustering technique was used to select five representative air quality monitoring sites in Tehran to capture O3 and NOx concentrations' variability. The findings show that all of the investigated sites failed to meet the ozone non-attainment criterion. The ozone weekend effect is seen in the study of weekday/weekend differences in 2017 and 2018, but not in 2019, which can be due to the shift in the ozone production regime. The summer mean variation analysis can also be used to deduce this regime change. In 2017, the O3 and NO2 summer mean variations suggest a holdback in the NO2 upward trend and a reversal in the O3 downward trend that had been in place since 2012. Air mass back trajectory clustering reveals that east and north-east air mass clusters have the most significant impact on Tehran's O3 pollution and the highest regional contribution to OX. The study of OX against NOx shows that the regional contribution to OX increased from 2017 to 2018 and then decreased in 2019; however, the local contribution is the opposite. The diurnal analysis of the regional and local contributions to OX indicated that OX in Tehran might be primarily affected by pollutants from a short distance. The findings reveal critical changes in the behavior of O3 in recent years, indicating that decision-makers in Tehran should reconsider air pollution control measures.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Análise por Conglomerados , Monitoramento Ambiental , Irã (Geográfico) , Ozônio/análise
7.
Mar Pollut Bull ; 171: 112688, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34271510

RESUMO

This study investigated the impact of local anthropogenic activity on the marine environment around the remote harbor of Qeqertarsuaq, West Greenland. Blue mussels (Mytilus sp.) were used as a bioindicator, and their physiological condition was found to decrease with increasing proximity to the harbor. Subsequently, the distribution of 19 polycyclic aromatic hydrocarbons (PAHs) and 9 groups of alkylated PAHs were measured in mussel and sediment samples. The highest values were found in a rocky collection area 15 m from a wooden pier frequented by small boats. A PAH source investigation, indicated a mixed source from light fuel oils and creosote used as boat coating. Finally, correlations between the mussels morphological condition and the PAH pollution were found to be significant for 4-, 5-, and 6-ring PAHs. In conclusion, the results indicate that pollution sources in harbors have significant effects on the local environment and should be considered in arctic conservation research.


Assuntos
Mytilus edulis , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Biomarcadores Ambientais , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 751: 141740, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-32889466

RESUMO

The overall ozone concentration in China has increased significantly in recent years, as has the atmospheric oxidization, and both of these changes are impacting human activities. Measurements based on differential absorption lidar (DIAL) were conducted from June to October 2019 in order to investigate the vertical distribution of ozone in Guangdong Province. The vertical and horizontal distributions of ozone in six different cities were systematically examined during the summer and autumn and analyzed the two different ozone characteristics (local pollution and regional transport). TrajStat was used to analyze the ozone transport directions and potential contributions of in the summer and autumn, and the following results were obtained. In the cities of Guangzhou and Jiangmen, the ozone concentrations climbed significantly higher in autumn than in summer, with the ozone concentration reaching a height of 1000 m in autumn and 600 m in summer. The diurnal variation of ozone in Yangjiang City in summer was not obvious, whereas in other cities, high levels of ozone were concentrated in the afternoon. The average summer ozone concentration at the Guangzhou site was the highest, approximately 92.57 µg/m3, whereas the average at the Dongguan site was the lowest. The average ozone concentration at the Guangzhou site in autumn was also the highest among the six cities, reaching 133.34 µg/m3. In terms of local pollution, the high-concentration ozone mainly occurred near the ground. The maximum ozone concentration was approximately 162.1 µg/m3 at about 350 m, and the ozone was evenly distributed above 1500 m. The external transport of ozone primarily occurred from 500 to 1100 m and above 1100 m. During summer, the southwest airflow trajectory was dominant, whereas northeast airflow predominated in autumn.

9.
Chemosphere ; 244: 125520, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31816544

RESUMO

More than 400 PM1 and 400 PM10 daily samples were collected in the urban center of Elche (close to the Spanish Mediterranean coast) from February 2015 to February 2018. Samples were analyzed to determine the concentrations of major and trace components with the aim of evaluating the influence of specific pollution events on the chemical composition of both PM fractions. The concentrations of crustal elements in PM10 significantly increased during Saharan dust outbreaks, particularly titanium, which has been identified as a good tracer of these events in the study area. Sulfate and nitrate levels were also enhanced due to secondary aerosol formation on mineral dust particles. Local pollution episodes had a great impact on submicron nitrate, whose mean concentration was more than four times higher than on non-event days. The chemical mass closure method was used to reconstruct PM1 and PM10 concentrations. Reasonably good correlations between measured and reconstructed concentrations were obtained, except for PM10 samples collected during Saharan dust events. This was due to the underestimation of the dust contribution during these episodes. Moderate differences in the average chemical composition of PM10 were observed between event and non-event days. Regarding PM1, only local pollution episodes had a certain impact on its chemical composition.


Assuntos
Aerossóis/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Poeira/análise , Nitratos , Tamanho da Partícula , Material Particulado/análise , Sulfatos , Oligoelementos/análise
10.
J Environ Manage ; 227: 10-22, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30172155

RESUMO

From autumn to the following spring, annually, the northeast monsoon transports PM2.5 (particles less than 2.5 µm in aerodynamic diameter) from the Asian continent to downstream areas. Naturally, this triggered a question: What are the contributions of PM2.5 from long-range transport (LRT) and local pollution (LP) at any downstream location? To answer that question, the present study developed an economical and efficient method that can easily estimate the contribution of PM2.5 from LRT (LRT-PM2.5) and PM2.5 from LP (LP-PM2.5). The method used PM2.5 and meteorological observation data in Taiwan from 2006 to 2015 and a short-term simulation from January to May in 2010. The analysis classified the data into three types of PM2.5 source patterns: LRT-Event (high concentration plume at the front edge of southward moving anticyclones/strong northeast wind), LRT-Ordinary (less concentration in common strong northeast wind), and LRT/LP Mix or Pure LP (PM2.5 was from both LRT and LP or from only LP under weak northeast wind). During the ten-year period, the average LRT-PM2.5 values at the northern tip of Taiwan were 31-39 µg m-3, 12-16 µg m-3, and 4-13 µg m-3 for the LRT-Event, LRT-Ordinary, and LRT/LP Mix or Pure LP patterns, respectively. The 10-year average LRT-PM2.5 and LP-PM2.5 contributions were approximately 70:30 in northern Taiwan, 50:50 in central Taiwan, and 30:70 in southern Taiwan for the LRT-Event pattern; 60:40 in northern and 40:60 in central and southern Taiwan for the LRT-Ordinary pattern; and 30:70 in northern and 25:75 in central and southern Taiwan for the LRT/LP Mix or Pure LP pattern. Interestingly, LRT-PM2.5 peaked in 2013 but has decreased annually since then, whereas LP-PM2.5 has roughly decreased in the past ten years.


Assuntos
Poluentes Atmosféricos , Chuva , Monitoramento Ambiental , Material Particulado , Taiwan
11.
Aerosol Air Qual Res ; 18(7): 1788-1798, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32601523

RESUMO

In this study, an approach has been developed for differentiating between local and remote pollution over Taiwan, based on homogeneity perspective (variations of the standard deviation) of both AERONET measurements and NASA MERRA aerosol reanalysis (version 2, MERRA-2) over a 15-year period (2002 - 2017). The analysis of seasonal variations of the standard deviation of aerosol optical depth (AOD) measurements at six AERONET sites and MERRA AOD data in Taiwan showed that, in spring when remote aerosols dominate, the standard deviation is almost three times lower than that in autumn, when aerosols from local sources dominate. This finding was supported by MERRA AOD over the open ocean area: total AOD data were used to differentiate between local and remote pollution over both Taiwan and the open ocean area in the vicinity of Taiwan. Over Taiwan, MERRA total AOD showed a primary maximum in spring and a secondary one in autumn. Over the open ocean area, where there are no local sources of anthropogenic aerosols, MERRA total AOD showed only one maximum in spring and no maximum in autumn. This suggests that, in Taiwan, the maximum in autumn is attributed to local air pollution, while the pronounced maximum in spring is mainly caused by air pollution from continental Asia. The analyses of spatial distribution of 15-year monthly mean MERRA winds confirmed the above-mentioned results. Furthermore, similar to total AOD, MERRA sulfate AOD peaked in autumn over Taiwan, but not over the oceanic area: this indicates the contribution of local emissions of anthropogenic aerosols from the industrial sector. The standard deviation of MERRA sulfate AOD in spring is two-three times lower than the standard deviation in autumn: this is additional evidence that, in spring, sulfate aerosols from remote sources are predominant; while in autumn sulfate aerosols from local sources dominate.

12.
Sci Total Environ ; 551-552: 533-45, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26896582

RESUMO

To improve our understanding of the interplay among local and regional photochemical pollutants in the typical city of the Yangtze River Delta (YRD) region, the concurrent observation of O3 and NOx concentrations at an urban and a suburban site in Nanjing during 2008 is presented. In general, the annual mean O3 concentration is 2.35ppbv lower in the downtown than at suburban due to higher NOx pollution levels correlated with heavy traffic. At both sites, O3 shows a distinct seasonality with the spring maximum and the winter minimum, while the minimum concentration of NOx appears in summertime. Besides the chemical processes of O3 sensitivity in the daytime and the NOx titration at night, meteorological conditions also play an essential role in these monthly and diurnal variations. The ozone weekend effect that can be attributed to the weekly routine of human activities is observed in the urban atmosphere of Nanjing as well, with O3 concentrations 2.09ppbv higher and NOx concentrations 6.20ppbv lower on weekends than on weekdays. The chemical coupling of NO, NO2 and O3 is investigated to show that the OX-component (O3 and NO2) partitioning point occurs at about 35ppbv for NOx, with O3 being the dominant form at lower levels and NO2 dominating at higher levels. And it is also discovered that the level of OX is made up of two contributions, including the regional contribution affected by regional background O3 level and the local contribution correlated with the level of primary pollution. The diurnal peak of regional contribution appears 2-5h after the peak of local contribution, implying that OX in Nanjing might prominently affected by the pollutants from a short distance. The highest regional contribution and the second highest local contribution lead to the spring peak of O3 observed in Nanjing, whereas the highest local contribution and the moderate regional contribution make the O3 concentrations in summer higher than those in autumn and winter. Our results reveal the important environment impacts from meteorological conditions and human activities in the YRD region, and can help to understand O3 pollution in these polluted areas by just using the conventional observations.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Óxidos de Nitrogênio/análise , Ozônio/análise , Atmosfera/química , China , Cidades , Dióxido de Nitrogênio/análise
13.
Environ Pollut ; 197: 62-67, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25497307

RESUMO

This study investigates concentrations of 18 perfluoroalkyl substances (PFAS) in blood plasma of adult lactating Weddell seals (Leptonychotes weddellii) (n = 10) from McMurdo Sound, Antarctica. Perfluoroundecanoic acid (PFUnDA) was detected in all samples at concentrations ranging from 0.08 to 0.23 ng/ml. Perfluorooctane sulfonate (PFOS), perfluorohexanoate (PFHxA) and perfluorotridecanoate (PFTriDA) were sporadically detected, while the remaining compounds were below the limit of detection. This is the first report of detectible concentrations of PFASs in an endemic Antarctic marine mammal species. We suggest that the pollutants have been subjected to long range atmospheric transportation and/or derive from a local source. A review of these and published data indicate that perfluoroalkyl carboxylates (PFCAs) dominate in biotic PFAS patterns in species feeding south of the Antarctic Circumpolar Current (ACC), whereas PFOS was the major PFAS detected in species feeding predominantly north of the current.


Assuntos
Ácidos Alcanossulfônicos/metabolismo , Monitoramento Ambiental , Fluorocarbonos/metabolismo , Focas Verdadeiras/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Regiões Antárticas , Cetáceos , Feminino , Humanos , Lactação , Focas Verdadeiras/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA