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1.
Sci Total Environ ; 704: 135325, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31839317

RESUMO

Biotrickling filters (BTFs) applied to hydrophobic volatile organic compounds (VOCs) suffer from limited mass transfer. Phase transfer kinetic and equilibrium effects limit the biodegradation of hydrophobic VOCs especially at high concentrations. This study evaluates two strategies for overcoming the problem. First, a natural process was used to enhance the aqueous availability of styrene, a hydrophobic VOC model, by inoculating the BTF with a mixture of biosurfactant-generating bacteria. This method achieved a maximum elimination capacity (ECmax) of 139 g m-3h-1 in the BTF at an empty bed residence time (EBRT) of 60s. The highest concentrations of the biosurfactants surfactin and rhamnolipid were 205 and 86 mg L-1, respectively, in this step. Sequencing 16S rRNA confirmed the presence of biosurfactant-producing bacteria capable of biodegrading styrene in the BTF including Bacillus sonorensis, Bacillus subtilis, Lysinibacillus sphaericus, Lysinibacillus fusiformis, Alcaligenes feacalis, Arthrobacter creatinolyticus, and Kocuria rosea. Second, the effect of adding H2O2 to the recycle liquid on the BTF performance was determined. The biodegradation and mineralization of styrene in the BTF operated at a loading rate of 266 g m-3h-1 and H2O2/styrene molar ratio of 0.05 with EBRT as short as 15 s were 94% and 53%, respectively, with the EC of 250 g m-3h-1. High concentrations of antioxidant enzymes (peroxidase and catalase: 56 and 7 U gbiomass-1, respectively) were produced and biosurfactant generation was increased in this step, contributing to enhanced styrene biodegradation and mineralization. The styrene biodegradation and mineralization values in the BTF in the last day operated under similar conditions but without H2O2 were 11.4% and 5.3%, respectively. The bacterial population had no considerable change in the BTF after adding H2O2. Accordingly, stimulating the BTF inoculated with biosurfactant-generating bacteria with H2O2 is a promising strategy for improving the biodegradation of hydrophobic VOCs.


Assuntos
Poluentes Atmosféricos/metabolismo , Biodegradação Ambiental , Estireno/metabolismo , Poluentes Atmosféricos/análise , Reatores Biológicos , Peróxido de Hidrogênio , Estireno/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
2.
Environ Sci Pollut Res Int ; 26(36): 36754-36763, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31741276

RESUMO

Stereocaulon sorediiferum is expected to be a Cu-hyperaccumulator lichen and has fluorescent substances. To clarify the relationship between the fluorescence (FL) of the lichen and its Cu concentration, we collected S. sorediiferum samples at Cu-contaminated and uncontaminated sites in Japan, determined the concentration of Cu, K, Mg, Al, Ca, Mn, Fe, Zn, chlorophyll a,b, and total carotenoids in them, analyzed lichen secondary metabolites and fluorescent substances extracted from them, and measured the FL of them and their extracts. We found that the FL intensity of S. sorediiferum samples is significantly negatively correlated with their Cu concentration. The application of its FL for Cu monitoring may allow a new nondestructive quantitative method for assessing Cu contamination. The spectroscopic and chromatographic analysis shows that the fluorescent substances negatively correlated with Cu concentration are not major lichen secondary metabolites (lobaric acid and atranorin) and remain after immersion in acetone. The correlation analysis and the comparison with the causal relationship between Cu concentration and the chlorophyll a/b ratio suggest that the reason for the decrease in FL intensity with increasing Cu concentration is a structural change of the fluorescent substances by accumulated Cu. These findings lead to a better understanding of the relationship between the FL of S. sorediiferum and its Cu concentration and provide new insights into fluorescent lichen substances.


Assuntos
Poluentes Atmosféricos/toxicidade , Ascomicetos/efeitos dos fármacos , Cobre/toxicidade , Fluorescência , Poluentes Atmosféricos/metabolismo , Ascomicetos/metabolismo , Clorofila , Clorofila A , Cobre/análise , Cobre/metabolismo , Depsídeos , Hidroxibenzoatos , Japão , Lactonas , Líquens/química , Líquens/efeitos dos fármacos , Salicilatos
3.
J Dairy Sci ; 102(12): 11153-11168, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587912

RESUMO

Global warming caused by greenhouse gas emissions is a threat to the survival of humans and other organisms living on Earth. The greenhouse gases released from the dairy sector of New Zealand accounted for 18.2 Mt of carbon dioxide equivalent (CO2-eq) in 2016, mainly from methane generated by enteric fermentation in the rumen of milking cows and their replacement stock. A productivity commission established by the New Zealand government in 2018 estimated that methane emissions from livestock needed to be reduced from 2016 levels by 10 to 22% by 2050 (i.e., 2.8 to 6.1 million t lower), so as to restrict future increases in global temperature to less than 2°C. In this study, we evaluated genetic effects of 8 traits included in the New Zealand national dairy breeding objective, on 3 types of methane emissions metrics: gross methane emissions per dairy cow per year (E), methane emissions per hectare (EH), and methane emissions intensity per milk protein equivalents (EI), as carbon dioxide equivalents. These effects were then aligned with recent genetic changes in these traits brought about by breeding schemes, so that the overall genetic trend for each metric into the future was estimated. The results showed that EH and EI are currently being reduced at rates of -2.31 kg of CO2-eq per hectare per cow per year (current average is 6,915 kg of CO2-eq/ha per cow per year) and -0.04 kg of CO2-eq per kg of milk protein equivalents per cow per year, respectively (current average is 9.7 kg of CO2-eq/milk protein-eq per cow per year). These improvements directly reflect increased production efficiency through selection for farm profitability. If the pastureland area in New Zealand remains the same, at the same productivity and with no increase in supplementation rates from external land sources, in 20 years gross emissions would be reduced by only 0.6%, or 89 Mt. Increased production efficiency will likely result in corresponding changes to the stocking rate, to fully utilize the pasture resource available, and might further encourage a greater rate of intensification via supplementary feeding. Both consequences of current genetic selection could negate any benefits for the national greenhouse gas inventory. New selection criteria for reduced methane production are needed to help achieve New Zealand's national methane reduction targets.


Assuntos
Poluentes Atmosféricos/metabolismo , Cruzamento , Bovinos/metabolismo , Gases de Efeito Estufa/metabolismo , Metano/metabolismo , Animais , Dióxido de Carbono/análise , Bovinos/genética , Indústria de Laticínios/métodos , Feminino , Fermentação , Aquecimento Global , Leite , Proteínas do Leite/metabolismo , Nova Zelândia
4.
Nat Commun ; 10(1): 3866, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530803

RESUMO

Particle transfer across the placenta has been suggested but to date, no direct evidence in real-life, human context exists. Here we report the presence of black carbon (BC) particles as part of combustion-derived particulate matter in human placentae using white-light generation under femtosecond pulsed illumination. BC is identified in all screened placentae, with an average (SD) particle count of 0.95 × 104 (0.66 × 104) and 2.09 × 104 (0.9 × 104) particles per mm3 for low and high exposed mothers, respectively. Furthermore, the placental BC load is positively associated with mothers' residential BC exposure during pregnancy (0.63-2.42 µg per m3). Our finding that BC particles accumulate on the fetal side of the placenta suggests that ambient particulates could be transported towards the fetus and represents a potential mechanism explaining the detrimental health effects of pollution from early life onwards.


Assuntos
Poluentes Atmosféricos/metabolismo , Exposição Materna/efeitos adversos , Troca Materno-Fetal , Placenta/metabolismo , Fuligem/metabolismo , Poluentes Atmosféricos/toxicidade , Bélgica , Biópsia , Estudos de Coortes , Ecotoxicologia , Feminino , Humanos , Microscopia Eletrônica de Transmissão , Permeabilidade , Placenta/patologia , Placenta/ultraestrutura , Gravidez , Características de Residência/estatística & dados numéricos , Fuligem/análise , Fuligem/toxicidade
5.
Bull Environ Contam Toxicol ; 103(5): 750-755, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31555848

RESUMO

With increasing urbanization and industrialization, clean air is becoming a scarce resource. During the present investigation, concentrations of metals (Pb, Ni and Zn) in the atmosphere and their subsequent deposition in the lungs of two common avian species, common myna, Acridotheres tristis (n = 30) and bank myna, A. ginginianus (n = 20), captured from urban areas of Lahore city and semi-urban areas of Pattoki city 80 km away from main city of Lahore were determined. The obtained results were analyzed statistically using Independent sample t test and Pearson's correlation. A comparison of trace metal concentrations in air of both the cities was also carried out. Statistically, significant variations were recorded for Pb (t (7) = - 4.276, p = 0.001) while non-significant differences were observed for both Ni (t (7) = 0.049, p = 0.962) and Zn (t (7) = 1.555, p = 0.146).


Assuntos
Poluentes Atmosféricos/metabolismo , Aves/metabolismo , Monitoramento Ambiental/métodos , Pulmão/metabolismo , Metais Pesados/metabolismo , Oligoelementos/metabolismo , Animais , Bioacumulação , Cidades , Paquistão , Urbanização
6.
Environ Pollut ; 254(Pt A): 112933, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31382213

RESUMO

Exposure to fine atmospheric Particulate Matter (PM) is one of the major environmental causes involved in the development of inflammatory lung diseases, such as chronic obstructive pulmonary disease (COPD) or asthma. When PM is penetrating in the pulmonary system, alveolar macrophages represent the first line of defense, in particular by triggering a pro-inflammatory response, and also by their ability to recruit infiltrating macrophages from the bone marrow. The aim of this in vitro study was to evaluate the gene expression and cytokine production involved in the toxicological and inflammatory responses of infiltrating macrophages, as well as the Extracellular Vesicles (EVs) production, after their exposure to PM. The ability of these EVs to convey information related to PM exposure from exposed macrophages to pulmonary epithelial cells was also evaluated. Infiltrating macrophages respond to fine particles exposure in a conventional manner, as their exposure to PM induced the expression of Xenobiotic Metabolizing Enzymes (XMEs) such as CYP1A1 and CYP1B1, the enzymes involved in oxidative stress SOD2, NQO1 and HMOX as well as pro-inflammatory cytokines in a dose-dependent manner. Exposure to PM also induced a greater release of EVs in a dose-dependent manner. In addition, the produced EVs were able to induce a pro-inflammatory phenotype on pulmonary epithelial cells, with the induction of the release of IL6 and TNFα proinflammatory cytokines. These results suggest that infiltrating macrophages participate in the pro-inflammatory response induced by PM exposure and that EVs could be involved in this mechanism.


Assuntos
Poluentes Atmosféricos/toxicidade , Células Epiteliais/metabolismo , Vesículas Extracelulares/metabolismo , Macrófagos Alveolares/metabolismo , Material Particulado/toxicidade , Poluentes Atmosféricos/metabolismo , Linhagem Celular , Citocinas/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/metabolismo , Pneumopatias/induzido quimicamente , Estresse Oxidativo , Tamanho da Partícula , Material Particulado/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
7.
Sci Total Environ ; 693: 133404, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31377372

RESUMO

Major and trace element deposition across western Washington, USA was assessed in 2016 and 2017 by analyzing tissue metal concentrations in the epiphytic mosses Isothecium stoloniferum (Bridel) and Kindbergia praelonga (Hedw.) Ochyra. We used an intensive, vertically stratified sampling approach in Acer macrophyllum canopies in the Hoh Rainforest on the Olympic Peninsula, WA and in Seattle, WA to collect 214 samples of I. stoloniferum. An extensive, ground-based sampling approach was used across an urban-to-wildland gradient to collect 59 K. praelonga samples. Intensive samples were collected four times (April, July, and October of 2016 and in January 2017) and extensive samples three times (April, July, and October 2016) to assess seasonal differences in metal concentrations across sampling locations. A total of 273 moss samples were analyzed for Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Sr, Ti, and Zn concentrations. Elevated concentrations of these elements were found in moss samples from both intensive and extensive sampling efforts across all seasons. Sampling location for both intensive and extensive sampling efforts was found to be a significant factor in determining moss metal concentrations. Metal deposition in and around Seattle appears to be derived from the regional transportation sector and other industrial sources. Ten I. stoloniferum samples from Seattle and the Hoh Rainforest were analyzed for Pb and Sr isotope ratios to help differentiate between natural and industrial-based emission sources. Hoh Rainforest Pb isotopes appear to be explained by a mixture of long-range Asian Pb influences and natural Pb sources, whereas Seattle Pb isotopes appear driven by industrial and road dust sources.


Assuntos
Poluentes Atmosféricos/metabolismo , Bryopsida/química , Monitoramento Ambiental , Metais Pesados/metabolismo , Oligoelementos/metabolismo , Estações do Ano , Washington
8.
Chemosphere ; 237: 124522, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31401430

RESUMO

The present study was performed on Shorea robusta Gaertn., Acacia auriculiformis Benth., Eucalyptus globulus Labill., Azadirachta indica A. Juss in two tropical forests [including one (Barjora), situated adjacent to heavy pollution sources and the other, as control, Ballavpur Wildlife Sanctuary (BWLS)] of West Bengal, India, to measure the heavy metals accumulation capacity in their leaves and their levels of tolerance in a polluted environment. Site wise and seasonal variations in air pollution tolerance index (APTI) and anticipated performance index (API) were assessed in the aforesaid four plants. Highest APTI value was observed in S. robusta (34.62 ±â€¯1.47) at polluted site during winter. S. robusta anticipated as an excellent performer on the basis of API score in all the three seasons in BWLS. The metal accumulation index (MAI) values ranged from 3.06 to 7.68 and 9.48-9.82; 2.65-4.96 and 4.29-6.08; 3.35-8.14 and 5.04-11.65; 3.59-4.64 and 5.21-7.98 at BWLS and Barjora forest for S. robusta, A. auriculiformis, E. globulus and A. indica respectively. Two-way ANOVA test showed a site and season wise significant difference in the biochemical and physiological parameters between the two forests. The results indicated that air pollution played an important role, which affected the biochemical and physiological parameters of plants in tropical forest located at a polluted site. The species with highest MAI and APTI value could be used in sound green space management for reducing the levels of atmospheric pollution. Higher levels of ascorbic acid content, at polluted site as compared to control site, were an indication of stress condition.


Assuntos
Poluentes Atmosféricos/metabolismo , Monitoramento Ambiental , Metais Pesados/metabolismo , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Ácido Ascórbico/análise , Florestas , Índia , Indústrias , Metais Pesados/análise , Folhas de Planta/química , Plantas , Estações do Ano
9.
Environ Sci Pollut Res Int ; 26(29): 29620-29638, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463756

RESUMO

Mosses were proved as an ideal and reliable biomonitor as well as an indicator of atmospheric trace metal pollution. They are used as model indicator species of air pollution since long back due to their simple structure, genetic diversity, totipotency, rapid colony-forming ability, and high metal resistance behavior. Bryomonitoring technique is gradually being popularized as an economically viable procedure for estimating the degrees of environmental health and evaluating the toxic pollutants in biosphere. Thus, in the present scenario, many parts of the world use these organisms for monitoring the air pollution. This article describes an overview of the relationship of terrestrial mosses with trace metals with respect to their uptake, accumulation, and toxification as well as detoxification and tolerance mechanisms. The review article explicitly expresses the caliber of the cryptogamic mosses in establishing the pristine environment around the world. It also highlights the underpinning mechanisms and potential for future research directions. We have referred more than 250 articles, which deals with the assessment and impact of different heavy metals on 52 numbers of different moss species belongs to different climatic zones. The present review covers the research work in this area carried out worldwide since 1965.


Assuntos
Poluentes Atmosféricos/análise , Briófitas/efeitos dos fármacos , Briófitas/fisiologia , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes Atmosféricos/metabolismo , Poluentes Atmosféricos/toxicidade , Poluição do Ar , Briófitas/química , Bryopsida/química , Metais Pesados/metabolismo , Metais Pesados/toxicidade
10.
Bull Environ Contam Toxicol ; 103(3): 435-440, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267137

RESUMO

The air quality in north-eastern part of Moscow region was evaluated by trace metals atmospheric deposition using moss Pleurozium schreberi as bioindicator. Thirty six elements were determined in analyzed samples by Neutron activation analysis and Atomic absorption spectrometry. Principal component analysis was used to identify and characterize different pollution sources. Maps showing the geographical distribution of the factor scores were built using ArcGis software. Median values of the elements studied were compared with data obtained for other regions in Russia. The present survey showed that industrial activity, thermal power plants and transport still have the largest anthropogenic impact on air pollution in studied region.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental , Metais Pesados/análise , Poluentes Atmosféricos/metabolismo , Atmosfera/química , Bryopsida/metabolismo , Biomarcadores Ambientais , Indústrias , Metais Pesados/metabolismo , Moscou , Oligoelementos/análise
11.
Environ Int ; 131: 104971, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31284107

RESUMO

In mercury (Hg) contaminated areas of Asia, human exposure to toxic methyl-Hg (MeHg) through a rice-based diet of locally produced crop may pose a health threat. Alternative cropping system to rice in such areas would be most desirable. In this study, corn, the leading cereal source in the world with large biomass, was demonstrated to accumulate an insignificant amount of MeHg from the soil in its edible portion compared to that in rice, suggesting corn being a very competitive alternative crop. By examining Hg stable isotope composition, Hg in the aerial parts of corn was found to be mostly from the atmosphere. Maize cropping worldwide is estimated to be a discemible sink of atmospheric Hg with approximately 44 Mg Hg accumulated in each growing season on a yearly basis, most of which is from foliar uptake of atmospheric Hg and this amount is comparable to litterfall Hg observed in North America and Europe. It is thus recommended to use corn as a replacement of rice in highly Hg-contaminated areas for remediation of Hg pollution in the food supply.


Assuntos
Poluentes Atmosféricos/metabolismo , Mercúrio/metabolismo , Compostos de Metilmercúrio/metabolismo , Poluentes do Solo/química , Zea mays/metabolismo , Poluentes Atmosféricos/química , Poluentes Atmosféricos/toxicidade , Grão Comestível/química , Monitoramento Ambiental , Poluição Ambiental , Humanos , Mercúrio/análise , Mercúrio/toxicidade , Compostos de Metilmercúrio/análise , Compostos de Metilmercúrio/toxicidade , Medição de Risco , Poluentes do Solo/análise
12.
BMC Biotechnol ; 19(1): 52, 2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31345193

RESUMO

BACKGROUND: Packing materials is a critical design consideration when employing biological reactor to treat malodorous gases. The acidification of packing bed usually results in a significant drop in the removal efficiency. In the present study, a biotrickling filter (BTF2) packed with plastic balls in the upper layer and with lava rocks in the bottom layer, was proposed to mitigate the acidification. RESULTS: Results showed that using combined packing materials efficiently enhanced the removal performance of BTF2 when compared with BTF1, which was packed with sole lava rocks. Removal efficiencies of more than 92.5% on four sulfur compounds were achieved in BTF2. Average pH value in its bottom packing bed was about 4.86, significantly higher than that in BTF1 (2.85). Sulfate and elemental sulfur were observed to accumulate more in BTF1 than in BTF2. Analysis of principal coordinate analysis proved that structure of microbial communities in BTF2 changed less after the shutdown but more when the initial pH value was set at 5.5. Network analysis of significant co-occurrence patterns based on the correlations between microbial taxa revealed that BTF2 harbored more diverse microorganisms involving in the bio-oxidation of sulfur compounds and had more complex interactions between microbial species. CONCLUSIONS: Results confirmed that using combined packing materials effectively improved conditions for the growth of microorganisms. The robustness of reactor against acidification, adverse temperature and gas supply shutdown was greatly enhanced. These provided a theoretical basis for using mixed packing materials to improve removal performance.


Assuntos
Filtros de Ar/microbiologia , Reatores Biológicos/microbiologia , Microbiota , Compostos de Enxofre/isolamento & purificação , Compostos de Enxofre/metabolismo , Poluentes Atmosféricos/isolamento & purificação , Poluentes Atmosféricos/metabolismo , Biodegradação Ambiental , Filtração/instrumentação , Filtração/métodos , Oxirredução
13.
Environ Pollut ; 252(Pt A): 344-351, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31158663

RESUMO

Nitrogen oxide (NOx) emissions from flue gas lead to a series of environmental problems. Biological removal of Nitrogen oxide (NOx) from flue gas by microalgae is a potential approach for reducing the problems caused by these emissions. However, few microalgal strains are reported to remove NOx from flue gas. Here, a microalga strain PF3 (identified as Scenedesmus obliquus), which can remove NOx and fix CO2 from flue gas is isolated. The tolerance of Scenedesmus obliquus PF3 to CO2, NO, SO2 and its adaptabilities to environmental factors (pH and temperature), and its performance in the removal of NO and CO2 are investigated. Scenedesmus obliquus PF3 showed biomass accumulation when sparged with 15% CO2 or 500 ppm NO or 50 ppm SO2, and bisulfite less than 2 mM showed no toxicity to Scenedesmus obliquus PF3. Additionally, PF3 grew well in a wide range of pH and temperatures from 4.5 to 10.5 and 15 °C-30 °C, respectively. When sparged with simulated flue gas (100 ppm NO, 10% CO2, (N2 as balance gas)), the microalgae culture system removed NO and CO2 at a rate of 2.86 ±â€¯0.23 mg L-1 d-1 and 1.48 ±â€¯0.12 g L-1 d-1, respectively, where up to 96.9 ±â€¯0.03% (2.77 ±â€¯0.08 mg L-1 d-1) and 87.7 ±â€¯6.22% (1.29 ±â€¯0.01 mg L-1 d-1) of the removed NO and CO2, respectively, were assimilated in algal biomass. These results suggest that Scenedesmus obliquus PF3 is a promising candidate for NOx removal and carbon fixation of flue gas.


Assuntos
Biodegradação Ambiental , Dióxido de Carbono/metabolismo , Microalgas/metabolismo , Óxido Nítrico/metabolismo , Scenedesmus/metabolismo , Adaptação Fisiológica/fisiologia , Poluentes Atmosféricos/metabolismo , Poluição do Ar/análise , Biomassa , Ciclo do Carbono/fisiologia
14.
Biosci Biotechnol Biochem ; 83(9): 1650-1654, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31088333

RESUMO

The pathogenic fungi Gibberella fujikuroi and Fusarium commune produce jasmonic acid. The application of volatile deuterium-labeled methyl jasmonate increased the amount of nonlabeled JA present in G. fujikuroi and F. commune. These results indicate that the fungi have the ability to react with airborne methyl jasmonate in a manner similar to a plant.


Assuntos
Acetatos/metabolismo , Ciclopentanos/metabolismo , Fusarium/metabolismo , Gibberella/metabolismo , Oxilipinas/metabolismo , Plantas/metabolismo , Poluentes Atmosféricos/metabolismo
15.
Ecotoxicology ; 28(5): 578-588, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31140045

RESUMO

Active urbanization processes exacerbate environmental problems associated with industrial pollution in cities. Urban greening helps reduce level of air pollution and improve microclimate. Selection sensitive plant species (indicators of pollution), and the resistant species (decrease the level pollution) is acute in many countries. The aim of the present work was to establish concentrations of heavy metals (Fe, Mn, Zn, Cu, Ni, Cr, Pb, Co and Cd) in the Siberian larch needles grown in various urban land-use (functional) zones of Ulan-Ude (Russia), as well as to determinate and compare the levels of some biochemical compounds. Based on index of soil contamination, the highest heavy metal pollution was found in the highway and industrial zones. The index of biogeochemical transformation of the needle elements composition ranged from 5.1 (minimal level) to 32.2 (strong level). The most polluted sites were along highways, where Fe, Zn, Cu, Cr, Ni, Pb, and Cd concentration in the needles were up to 2.5-7.7 times than background values. An important role in the protective system of larch is played by pigments, especially Chl b and carotenoids. Their content in the needles is increased by 1.3-2.2 times. Ratio Chl a/b and ∑Chl/carotenoids decrease as compared to background level; in the first case-due to increase of Chl b content, in the second case-increase of carotenoids level. Highest concentrations of proline, condensed tannins and peroxidase activity were found in needles from urban zones connected with high traffic and industrial emission. Based on the Air Pollution Tolerance Index Siberian larch should be considered sensitive species to air pollution and can be recommended as bioindicator.


Assuntos
Monitoramento Ambiental , Larix/metabolismo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Poluentes Atmosféricos/metabolismo , Larix/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Federação Russa
16.
Environ Monit Assess ; 191(6): 400, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31134346

RESUMO

Air pollution is a very serious current environmental issue of human society. Large parts of countries, especially the densely populated cities, having high vehicular movement, industries, and factories, are worst affected. Biomarkers are changes in plant parameters that help in easy assessment of the environmental quality of an area at a certain time. Plants can react to different environmental stresses with the most evident responses shown by the leaves. In the present work, we have studied changes in biochemical parameters in the leaves of a mango plant (Mangifera indica), a very common plant in West Bengal, India, which were collected from four different locations in the city of Kolkata which has a high concentration of air pollutants and one control area from a rural region having a low concentration of air pollutants. It was observed that leaves which were exposed to high amounts of harmful air pollutants showed higher accumulation of molecules such as phenol, proline, malondialdehyde, and cellulose with lower amounts of chlorophyll. From this, we can observe that common environmental stress such as air pollution leads to a change in the synthesis of bioactive molecules to resist the effect of stress on the plant. Thus, from these data, it can be concluded that biochemical parameters can serve as efficient biomarkers of the air quality of an area.


Assuntos
Poluição do Ar/análise , Monitoramento Ambiental/métodos , Mangifera/metabolismo , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/metabolismo , Biomarcadores/análise , Biomarcadores/metabolismo , Clorofila/análise , Índia , Folhas de Planta/química , Folhas de Planta/metabolismo
17.
Ecotoxicol Environ Saf ; 180: 679-685, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31146154

RESUMO

Two lichen species, Usnea aciculifera and Usnea luridorufa, were used as biomonitors for the deposition of traffic-related metals in China's Shennongjia National Nature Reserve. The suitability of the two lichen species for use as biomonitors was compared. The health threat to the Sichuan snub-nosed (aka golden) monkey (Rhinopithecus roxellana) from consuming lichen with elevated metal concentrations due to vehicular traffic was then assessed. Lichens, with large surface areas and neither roots nor stomata, efficiently absorb both particulate and gaseous air pollutants. The resulting data was used to assess the effect of heavy metal accumulation on the lichens as well as the health risk imposed on the monkeys as lichen is a primary food source. Lichen samples were collected in the core area of the reserve at three locations of varying traffic intensity. A forth site in the reserve, with no proximate traffic, was used as the control. Results show: (1) lichen from high traffic sites has significantly higher concentrations of Fe, Cd, Pb Zn, and Cr than lichen collected from the control site; (2) vehicular traffic is the primary source of metals in lichen; (3) U. luridorufa collected at high traffic sites displayed decreased photosynthetic efficiency, an indication of stress; (4) intake of Cd and Pb from vehicle emissions in the Shennongjia National Nature Reserve could adversely affect snub-nosed monkey health. This research advances the science of biomonitoring, contributes to environmental protection efforts in China's nature reserves and helps improve food safety for Sichuan snub-nosed monkey, a national treasure of China.


Assuntos
Colobinae/fisiologia , Biomarcadores Ambientais/efeitos dos fármacos , Líquens/efeitos dos fármacos , Metais Pesados/toxicidade , Emissões de Veículos/toxicidade , Poluentes Atmosféricos/metabolismo , Poluentes Atmosféricos/toxicidade , Animais , China , Conservação dos Recursos Naturais , Líquens/metabolismo , Metais Pesados/metabolismo , Medição de Risco
18.
Sci Total Environ ; 683: 371-379, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31136964

RESUMO

Due to the development of the economy, electronic waste (e-waste) has become a new global problem and e-waste dismantling processes are an important source of air pollution. Among the pollutants emitted, polycyclic aromatic hydrocarbons (PAHs) are a severe concern because of their carcinogenic and mutagenic properties. However, few studies have investigated the atmospheric PAHs generated by e-waste dismantling in a specific region, especially the PAH levels throughout the year. Thus, we assessed the effects of PAHs on the local air quality by sampling the total suspended particulates (TSP), PM10, PM2.5, and gaseous phase from an e-waste dismantling area and a control site during four seasons. The TSP, PM10, and PM2.5 concentrations were measured as 84.8-414, 70.7-302, and 57.1-204 µg m-3, respectively, in this area, and those of three types of particulate bound-PAHs and gaseous phase PAHs were 2.6-16.1, 2.2-15.1, 1.9-14.6, and 20.1-72.8 ng m-3, respectively. The pollutant levels were higher in the spring and winter than those in the summer and autumn. The PAH sources were identified by diagnostic ratio approaches and principal component analysis. E-waste dismantling was identified as the major source of PAH pollution within this area, where approximately 82.4% of the PAHs was attributed to e-waste dismantling at an industrial park (EP site). Among the sites sampled, the pollutant levels and cancer risk were highest at the EP site, and they could pose a cancer risk for humans, although only the bioaccessible PAHs in human lungs were considered. In particular, infants had a higher health risk than adults, thereby suggesting that air pollution with PAHs is a concern in this area. This study provides clear evidence of the requirement for control measurements of e-waste dismantling processes.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Resíduo Eletrônico/análise , Monitoramento Ambiental , Exposição por Inalação/estatística & dados numéricos , Hidrocarbonetos Policíclicos Aromáticos/análise , Adulto , Poluentes Atmosféricos/metabolismo , Humanos , Pulmão/metabolismo , Material Particulado/análise , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Estações do Ano
19.
Sci Total Environ ; 659: 1546-1554, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31096364

RESUMO

In this study, we investigated the levels of 12 priority polycyclic aromatic hydrocarbons (PAH12) pollutants, bioaccessible PAH12, and sorption sink for PAH12 by a silicone sheet of indoor dust samples, which were collected from teachers' offices (n = 17), students' offices (n = 17), laboratory (n = 11), and experimental center (n = 9), using an in vitro digestive model. In PAH12, bioaccessible PAH12, and sorption sink PAH12, benzo[b]fluoranthene (BbF), phenanthrenes (Phe), and fluoranthene (FLA) were labeled respectively the most significant PAHs (6.61 ±â€¯4.42 µg/g, 0.16 ±â€¯0.11 µg/g, and 0.08 ±â€¯0.06 µg/g) after indoor dust ingestion, whereas the proportions of anthracene (Ant), benzo(g,h,i)perylene (BghiP), and BghiP (0.34 ±â€¯0.17, 0.03 ±â€¯0.03 and 0.01 ±â€¯0.01 µg/g) were low. Based on benzo[a]pyrene- equivalent carcinogenic concentrations, the mean daily exposure of bioaccessible PAH12 and sorption sink for PAH12 by indoor dust ingestion was 4.07 × 10-3 ±â€¯1.73 × 10-3 and 3.23 × 10-3 ±â€¯1.36 × 10-3 µg/day in the experimental center; 4.01 × 10-3 ±â€¯2.05 × 10-3 and 1.46 × 10-3 ±â€¯6.72 × 10-4 µg/day in students' offices; 8.25 × 10-4 ±â€¯2.33 × 10-4 and 5.15 × 10-4 ±â€¯1.37 × 10-4 µg/day in laboratory; and 7.05 × 10-4 ±â€¯4.12 × 10-5 and 2.82 × 10-4 ±â€¯4.36 × 10-5 µg/day in teachers' offices, respectively. Our results indicated that the passive transfer fraction of PAH12 (44.07%-67.36% in this case) is therefore large and needs to be considered in exposure and risk assessments.


Assuntos
Poluentes Atmosféricos/metabolismo , Poluição do Ar em Ambientes Fechados/análise , Exposição Dietética/análise , Poeira/análise , Intestino Delgado/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Atmosféricos/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Benzo(a)pireno , Carcinógenos , Exposição Dietética/estatística & dados numéricos , Digestão , Ingestão de Alimentos , Monitoramento Ambiental , Fluorenos , Humanos , Fenantrenos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco
20.
Biofactors ; 45(4): 536-547, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31087730

RESUMO

The effects of environmental insults on human health are a major global concern. Some of the most noxious pollutants that humans are exposed to include ozone (O3 ), particulate matter (PM), and cigarette smoke (CS). Since the skin is the first line of defense against environmental insults, it is considered one of the main target organs for the harmful insults of air pollution. Thus, there is solid evidence that skin pathologies such as premature aging, atopic dermatitis (AD), and psoriasis are associated with pollutant exposure; all of these skin conditions are also associated with an altered redox status. Therefore, although the mechanisms of action and concentrations of O3 , PM, and CS that we are exposed to differ, exposure to all of these pollutants is associated with the development of similar skin conditions due to the fact that all of these pollutants alter redox homeostasis, increasing reactive oxygen species production and oxidative stress. A main product of oxidative stress, induced by exposure to the aforementioned pollutants, is 4-hydroxy-2-nonenal (HNE), which derives from the oxidation of ω-6 polyunsaturated fatty acids. HNE is a highly reactive compound that can form adducts with cellular proteins and even DNA; it is also an efficient cell signaling molecule able to regulate mitogen-activated protein kinase pathways and the activity of redox-sensitive transcription factors such as Nrf2, AP1, and NFκB. Therefore, increased levels of HNE in the skin, in response to pollutants, likely accelerates skin aging and exacerbates existing skin inflammatory conditions; thus, targeting HNE formation could be an innovative cosmeceutical approach for topical applications.


Assuntos
Poluentes Atmosféricos/toxicidade , Aldeídos/toxicidade , Dermatite Atópica/induzido quimicamente , Material Particulado/toxicidade , Psoríase/induzido quimicamente , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Poluentes Atmosféricos/metabolismo , Aldeídos/metabolismo , Dermatite Atópica/genética , Dermatite Atópica/metabolismo , Dermatite Atópica/patologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Oxirredução , Estresse Oxidativo , Ozônio/metabolismo , Ozônio/toxicidade , Psoríase/genética , Psoríase/metabolismo , Psoríase/patologia , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Pele/metabolismo , Pele/patologia , Envelhecimento da Pele/genética , Envelhecimento da Pele/patologia , Poluição por Fumaça de Tabaco/efeitos adversos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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