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1.
J Environ Manage ; 270: 110671, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721281

RESUMO

The environmental information disclosure system is regarded as an important environmental management tool for supervising the environmental behavior of listed companies in China. To explore what drives the environmental information disclosure, a configurational analysis targeted at 264 China's key pollutant-discharge listed companies was studied by fuzzy-set qualitative comparative analysis (fs/QCA). The results showed that there were three types of paths to drive the environmental information disclosure: "Strict regulation - low resources - weak capability", "Strict regulation - low resources - strong capability" and "Strict regulation - high resources - strong capability", and that strict environmental regulation played a greatly significant role for promoting the environmental information disclosure level. The research provides a theoretical basis for the effectiveness of environmental regulation on environmental information disclosure, and it charts the future direction for environmental management in China.


Assuntos
Poluentes Ambientais , China , Revelação
2.
J Environ Manage ; 270: 110819, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721296

RESUMO

China is experiencing serious atmospheric pollution, which also exhibits significant spatial heterogeneity. The Chinese government has implemented targeted pollution control measures at the city level, emphasizing coordination among cities to prevent and control air pollution in key regions such as Beijing-Tianjin-Hebei (BTH) urban agglomeration. This study combined an inter-city multi-regional input-output (MRIO) model with an air quality dispersion model consisting of a weather research and forecasting (WRF) model and the CALPUFF model (WRF/CALPUFF) to study the inter-city economic consumption, pollutant emission and concentration among 13 cities in BTH urban agglomeration. NOx is chosen as an example. The combined effects of economic linkage and atmospheric transport show that NOx concentrations in cities in the BTH urban agglomeration are attributable to three consumption sources: a local contribution from the target city's own local economic consumption (average, 25%), and non-local consumption contributions, including other cities in the BTH urban agglomeration (average, 36%) and regions outside of BTH (average, 39%). Compared with the contributions to NOx concentrations calculated using only the MRIO model or atmospheric transport stimulation model, the results of this paper quantify that the consumption outside of a city could provide a greater impact on the city's air quality due to the combined effects of economic linkage and atmospheric transport. To avoid negative impacts of emission reduction targets on economic consumption, governmental regional pollution control policies should consider the combined effects of economic linkage and atmospheric transport.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/análise , Poluentes Ambientais , Pequim , China , Cidades , Monitoramento Ambiental , Material Particulado/análise
3.
J Environ Manage ; 270: 110906, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721341

RESUMO

The evolution of modern technology and industrial processes has been accompanied by an increase in the utilization of chemicals to derive new products. Water bodies are frequently contaminated by the presence of conventional pollutants such as dyes and heavy metals, as well as microorganisms that are responsible for various diseases. A sharp rise has also been observed in the presence of new compounds heretofore excluded from the design and evaluation of wastewater treatment processes, categorized as "emerging pollutants". While some are harmless, certain emerging pollutants possess the ability to cause debilitating effects on a wide spectrum of living organisms. Photocatalytic degradation has emerged as an increasingly popular solution to the problem of water pollution due to its effectiveness and versatility. The primary objective of this study is to thoroughly scrutinize recent applications of titanium dioxide and its modified forms as photocatalytic materials in the removal and control of several classes of water pollutants as reported in literature. Different structural modifications are used to enhance the performance of the photocatalyst such as doping and formation of composites. The principles of these modifications have been scrutinized and evaluated in this review in order to present their advantages and drawbacks. The mechanisms involved in the removal of different pollutants through photocatalysis performed by TiO2 have been highlighted. The factors affecting the mechanism of photocatalysis and those affecting the performance of different TiO2-based photocatalysts have also been thoroughly discussed, thereby presenting a comprehensive view of all aspects involved in the application of TiO2 to remediate and control water pollution.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água/análise , Catálise , Titânio , Água
4.
J Environ Manage ; 270: 110911, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721345

RESUMO

The adsorption-desorption behavior of methylene blue, acid orange 7, bisphenol A, and phenol on the synthesized graphene-based nanomaterials were studied. For this purpose, adsorption experiments were conducted in a batch setup and different parameters such as contact time, pH, adsorbent dose concentration, and initial micropollutant concentration were considered. In addition, linear and nonlinear kinetic and isotherm models were evaluated. The nonlinear pseudo-second-order models (R2 > 0.98), Elovich kinetic models (R2 > 0.94), and Langmuir isotherm models (R2 > 0.98) best fitted the experimental data. Because of the high specific surface area and the type of oxygen functional groups, mechanochemically synthesized graphite oxide exhibited high adsorption capacities for methylene blue, acid orange 7, bisphenol A, and phenol, with a maximum uptake of 288, 232, 110, and 68 mg g-1, respectively. Furthermore, the total costs of applying the mechanochemically synthesized graphite oxide were estimated in the adsorption process, revealing that these nanomaterials offer better uptake values than porous carbon.


Assuntos
Poluentes Ambientais , Grafite , Nanoestruturas , Poluentes Químicos da Água/análise , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Azul de Metileno , Modelos Teóricos
5.
J Environ Manage ; 270: 110919, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721351

RESUMO

Watermilfoil (Myriophyllum) is one of the world's most troublesome invasive aquatic weeds. Although current management practices may inhibit its expansion, it also impacts not only the quality of water but habitat deterioration. Therefore, the need for developing highly efficient and low-cost biotechnologies with resource recovery into the agriculture field as a complementary management strategy cannot be overstated. Here, we reviewe the scientific/grey literature to offer readers a precise and panoramic view of the invasive watermilfoil ecology, regional problems, impacts, ecosystem services, and management. In this regard, an in-depth review aimed to assess the potential for reducing non-point source inorganic and organic pollutants using invasive watermilfoil, with the sustainable approaches, while offering other services and mitigating ecological trade-offs is presented. Global distributions, growth, and current progress on the management and utilization of invasive watermilfoil biomass are summarized to develop the aim, which is to convey challenges during the implementation of large-scale weed use. In short, pollutant assimilation in plant and bacterial communities linked to this weed considerably contribute to the reduction and degradation of pollutants from both natural and artificial systems. Although several considerations in recycling and reusing biomass need to be considered, the potential reuse of the harvested material for livestock feed, compost and direct use in farming systems offer an additional strategy to achieve sustainable ecosystem restoration. Further research and development may focus on a more detailed economic modeling approach that integrates the costs (worker's wage, harvesting, transportation, and energy consumption), legal and regulatory barriers, health risks and ecosystem service benefits (biodiversity improvement, and pollutant removal) to holistically evaluate the economic, environmental, and societal value of reusing and recycling this waste material.


Assuntos
Ecossistema , Poluentes Ambientais , Agricultura , Biodiversidade , Biomassa
6.
Biomed Environ Sci ; 33(6): 403-413, 2020 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-32641203

RESUMO

Objective: To verify the health advisory for short-term exposure to phenol. Methods: The method of this validation experiment was the same as the US Environmental Protection Agency (EPA) methodology for toxicology experiments used to determine phenol drinking water equivalent level (DWEL). Pregnant female Sprague-Dawley rats were administered phenol in distilled water by gavage at daily doses of 15, 30, 60, 120, and 240 mg/kg body weight (b.w.) from implantation (the 6th day post-mating) to the day prior to the scheduled caesarean section (the 20th day of pregnancy). The following information was recorded: general behavior; body weight; number of corpus luteum, live birth, fetus, stillbirth, and implantation; fetal gender; body weight; body length; tail length; and abnormalities and pathomorphological changes in the dams. Results: In the 60 mg/kg b.w. dose group, the mortality of pregnant rats increased with increasing doses, suggesting maternal toxicity. Fetal and placental weights decreased as phenol dose increased from 30 mg/kg b.w., and were significantly different compared those in the vehicle control group, which suggested developmental toxicity in the fetuses. However, the phenol-exposed groups showed no significant change in other parameters compared with the vehicle control group ( P > 0.05). Conclusion: Despite using the same method as the US EPA, a different NOEAL of 15 mg/(kg·d) was obtained in this study.


Assuntos
Poluentes Ambientais/toxicidade , Desenvolvimento Fetal/efeitos dos fármacos , Fenol/toxicidade , Animais , Relação Dose-Resposta a Droga , Feminino , Gravidez , Ratos , Ratos Sprague-Dawley , Testes de Toxicidade Aguda
7.
Chemosphere ; 255: 127003, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32679629

RESUMO

In this study, we assessed the presence of 14 phthalate metabolites in the urine of 104 lactating mothers from Valencia (Spain) who took part in the human biomonitoring project BETTERMILK. Nine of the metabolites studied showed detection frequencies >80%, whereas the rest of the metabolites presented low detection frequencies (<5%). The concentrations ranged from

Assuntos
Monitoramento Biológico , Aleitamento Materno/estatística & dados numéricos , Exposição Materna/estatística & dados numéricos , Ácidos Ftálicos , Adulto , Coleta de Dados , Dietilexilftalato , Exposição Ambiental/análise , Poluentes Ambientais/metabolismo , Feminino , Humanos , Lactação , Mães , Embalagem de Produtos , Medição de Risco , Espanha
8.
Water Sci Technol ; 81(9): 1983-1993, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32666951

RESUMO

Fe2O3/ZrO2 nanocomposite photocatalyst was successfully prepared by coprecipitation method for the degradation of diesel pollutants in seawater under visible light. The effects of doping ratio, calcination temperature, photocatalyst dosage, initial diesel concentration, H2O2 concentration, and reaction time on the photocatalytic removal efficiency were investigated. Moreover, the optimal conditions for Fe2O3/ZrO2 nanocomposite photocatalyst to degrade marine diesel pollution were determined. The removal efficiency of diesel by nanocomposite photocatalyst could reach 97.03%. A photocatalyst-loaded polypropylene polyhedral ball was prepared, and the removal efficiency of diesel by photocatalyst-loaded polypropylene polyhedral ball decreased from 99.35 to 68.84% after four recycling cycles.


Assuntos
Poluentes Ambientais , Catálise , Peróxido de Hidrogênio , Luz , Água do Mar
9.
Mar Pollut Bull ; 157: 111309, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658675

RESUMO

Tsitsikamma and Sheffield Beach are two relatively pristine sites along the South African east coast representing warm temperate and subtropical biogeographic rocky shore intertidal ecosystems, respectively. Stable isotopes (δ15N and δ13C), metals and organochlorine pesticides (OCPs) were measured in 38 intertidal components to study biomagnification or biodilution of metals and OCPs in these marine food webs. Comparison of the four species common to both sites revealed that the highest Al, Fe and OCP concentrations were measured in intertidal organisms from Sheffield Beach and was attributed to diffuse input into the nearshore marine environment sources via estuaries and groundwater. All other metals were higher in intertidal organisms from Tsitsikamma and were attributed to the metal-rich phytoplankton blooms during upwelling events. There was no correlation between metal and OCP accumulation and dietary source (δ13C) or trophic level (δ15N). The application of trophic magnification factors (TMFs) using a relatively short benthic food chain indicated biomagnification for As, Cd, Cu, Se and Zn and biodilution of OCPs at both sites. Since these food chains represent only a small portion of the intertidal ecosystems we found limited evidence of biomagnification or biodilution of metals and OCPs across species. This was attributed to different dietary sources in the same food web and similar trophic levels being occupied by the same species in different food chains. We found that food web composition rather than temperature-based biogeographical distribution influenced trophic transfer of metals and OCPs.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água/análise , Ecossistema , Monitoramento Ambiental , Peixes , Cadeia Alimentar , África do Sul
10.
Mar Pollut Bull ; 157: 111316, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32658681

RESUMO

Marine ecosystems are structured by an array of natural and anthropogenic drivers, their diverse influences varying between different community types and across space. We assessed consistency in variation in composition and richness for three communities (macro- and meio-faunal communities associated with macroalgae, and soft-sediment infaunal communities) across natural and pollution gradients at the subcontinental scale of southeastern Australia. Community structure varied with natural environmental factors (temperature, wave exposure) and, to a lesser extent, pollutant loads (catchment effects, heavy metals, hydrocarbons and nutrients) across 43 sites spanning 2700 km. The community types showed differing sensitivities to pollutants: algal macrofauna was most strongly associated with hydrocarbon pollution and nutrient loading; algal meiofauna with heavy metals and nutrients; and infauna with catchment effects and nutrients. Different taxonomic resolutions were needed to detect significant pollution relationships for the three community types, indicating that monitoring programmes are most effective if pollutant- and fauna-specific.


Assuntos
Poluentes Ambientais , Metais Pesados/análise , Poluentes Químicos da Água/análise , Animais , Austrália , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Invertebrados
11.
J Environ Manage ; 268: 110661, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510430

RESUMO

Nitrogen contamination of groundwater has become a global issue and has aroused considerable concern among authorities. However, it is difficult to trace nitrogen sources in settings where a municipal solid waste (MSW) landfill site co-exists with intensive agriculture and other human activities. Therefore, a field investigation that combined a statistical analysis (factor analysis: FA) and hydrochemical analysis was designed and undertaken to identify nitrogen-pollutant sources in the shallow groundwater beneath an MSW landfill near to an agricultural area and human settlement. The results of the case study showed that nitrate was the specific pollutant produced by agricultural non-point-sources (Pbi = 15.5) and domestic pollution sources (Pbi = 41.0). The total phosphorus (Pbi = 37.2) and organic matter (Pbi = 16.6) were the specific pollutants released by the aquaculture and animal husbandry point-sources, and chloride (Pbi = 75.4) and organic matter (Pbi = 16.1) were the specific pollutants produced by the landfill. In the investigated area, the domestic pollution sources and agricultural non-point-sources were the most likely sources of nitrate contamination in the shallow aquifer. However, the landfill source and the aquaculture and animal husbandry point sources were the most likely sources of ammonium contamination. The combined method used in this study could successfully identify the nitrogen pollution sources in the shallow groundwater beneath an MSW landfill located in the vicinity of multiple pollutant sources. The method could be used to improve the control of nitrogen contamination and the management of groundwater quality.


Assuntos
Poluentes Ambientais , Água Subterrânea , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Humanos , Nitrogênio , Resíduos Sólidos , Instalações de Eliminação de Resíduos
12.
Chemosphere ; 256: 127159, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32559890

RESUMO

Although epidemiological and animal studies suggest a possible correlation between bisphenol A (BPA) exposure and atherosclerosis, very few in vitro mechanistic and functional studies regarding the effect of BPA on vascular cells have been conducted. Here, we applied a "real-life" exposure scenario by continuously exposing human endothelial cell (EC) line EA.hy926 to environmentally relevant concentrations of BPA (10-9, 10-8, and 10-7 M) during 14 weeks. We also exposed EA.hy926 cells to higher concentrations of BPA (10-7, 10-6, and 10-5 M) for up to 48 h to gain mechanistic insight into the BPA's action in ECs. Chronic exposure to BPA produced some unexpected effects in EA.hy926 cells including a transient decrease in the adhesion of monocytes to the EC monolayer and decrease in the expression of cellular adhesion molecules, improvement in endothelial barrier function and elevated expression of tight junction proteins occludin and zonula occludens-1 (ZO-1), increased adhesion of ECs, and increased nitric oxide (NO) production. Some of these effects, such as diminished adhesion of monocytes to the EC monolayer and elevated NO production have also been replicated during acute exposure experiments. Using Western blotting and specific pharmacological inhibitors in the acute study, we have shown that direct BPA's action in EA.hy926 cells involves activation of estrogen receptor (ER), phosphorylation of protein kinase B (PKB/Akt) and endothelial nitric oxide synthase (eNOS)-mediated production of NO. Collectively, these data indicate that BPA induces functional and molecular changes in EA.hy926 cells associated with the promotion of endothelial integrity through activation of the ER/Akt/eNOS pathway.


Assuntos
Compostos Benzidrílicos/toxicidade , Poluentes Ambientais/toxicidade , Fenóis/toxicidade , Linhagem Celular , Células Endoteliais/metabolismo , Humanos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Estrogênicos/metabolismo , Testes de Toxicidade
13.
Mar Pollut Bull ; 152: 110881, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32479273

RESUMO

In this study, we characterized plastic debris (PD) found on beaches from Concepción Bay in central Chile during spring 2017 and summer 2018. The identification of polymers was carried out using FT-IR. Persistent organic pollutants (POPs) were extracted with hexane using an ultrasonic bath and further quantified through GC-MS. The highest abundance of PD was obtained during the summer (4.1 ±â€¯3.7 items/m2), with the most common size range between 2.5 and 10 cm (42%) and the most frequent shape were plastic fragments (44%). FT-IR analysis showed that polypropylene was the most recurrent plastic polymer found. The ∑10PBDEs ranged from 2.1 to 1300 ng/g in spring 2017 and 392 to 3177 ng/g in summer 2018. ∑7PCBs ranged from 0.9 to 93 ng/g during the spring 2017 and 0.3 to 4.5 ng/g for summer 2018. This study is the first with information on POPs occurrence in the plastic debris of central Chile.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água/análise , Praias , Chile , Monitoramento Ambiental , Plásticos , Espectroscopia de Infravermelho com Transformada de Fourier , Resíduos/análise
14.
Sci Total Environ ; 736: 139444, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32485368

RESUMO

This work presents the optimization, validation, and verification of a miniaturized method for the determination of 360 environmental pollutants that are of toxicological concern for wildlife. The method implies a one-step QuEChERS-based extraction of 250 µl whole blood using acidified acetonitrile, followed by two complementary analyses by LC-MS/MS and GC-MS/MS. The optimized conditions allow the simultaneous determination of the major persistent organic pollutants, a wide range of plant protection products, rodenticides, pharmaceuticals, and a suite of metabolites that can be used as biomarkers of exposure. The method is very sensitive, and 95% of the pollutants can be detected at concentrations below 1.5 ng/ml. The method was applied to a series of 148 samples of nocturnal and diurnal wild raptors collected during field ecological studies in 2018 and 2019. Fifty-one different contaminants were found in these samples, with a median value of 7 contaminants per sample. As expected, five of the six contaminants that were detected in >50% of the samples were persistent or semi-persistent organic pollutants. However, it is striking the high frequency of detection of some non-persistent pollutants, such as 2-phenylphenol, benalaxyl, metaflumizone, diphenylamine, brodifacoum or levamisole, indicating the penetration of these chemicals into the food chains. The toxicological significance of all these findings should be studied in depth in future research. However, the results clearly demonstrated that the approach developed provides reliable, simple, and rapid determination of a wide range of pollutants in wildlife and makes it very useful to obtain valuable data in biomonitoring studies with only small amounts of sample.


Assuntos
Poluentes Ambientais/análise , Monitoramento Biológico , Cromatografia Gasosa , Cromatografia Líquida , Espectrometria de Massas em Tandem
16.
Environ Pollut ; 264: 114709, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32559862

RESUMO

Data on emission of atmospheric pollutants at local scale is essential for accurately modelling forest fire emission at regional scale. In this study, we quantified emission factor (EF) of gaseous pollutants (CO, CO2, NOx, hydrocarbons, organic carbon, and inorganic elements), fine particulate matter (PM2.5), water soluble inorganic ions, and non-methane hydrocarbons (NMHCs) from leaves, branches and barks of five dominant tree species in Chinese boreal region. Results demonstrate that the emission factors of different pollutants varied among tree species and fuel typology. The average total EF (leaves + branches + barks) of different species ranged from 922 ± 116 mg/g to 1383 ± 134 mg/g for CO2; 225 ± 109 mg/g to 277 ± 21 mg/g for CO; 0.6 ± 0.2 mg/g to 3 ± 0.7 mg/g for NOx; 32 ± 6 mg/g to 55 ± 7 mg/g for hydrocarbons; 3 ± 0.3 mg/g to 6 ± 0.7 mg/g for organic carbon; 0.6 ± 0.1 mg/g to 2 ± 0.1 mg/g for elemental carbon; and 4 ± 0.7 mg/g to 12 ± 1 mg/g for PM2.5. The total water soluble ions ranged from 5 ± 0.6 mg/kg to 12 ± 1.3 mg/g. For most of the pollutants, combustion of barks emitted more than that of leaves and branches. A total of 48 types of NMHCs (19 alkanes, 15 alkenes, and 14 aromatic compounds) were released during combustion of leaves, barks, and branches of tree species, with EF ranged from 982 mg/g to 1375 mg/g. Alkenes and i-butane, 1-butene, 1,3-butadiene, Isoprene, 4-Methyl-1-pentene, p-Xylene and benzene were the major ozone-forming compounds. Our results provide a comprehensive emission data by species and fuel typology that can be useful for modelling climate change, source apportionment and atmospheric photochemistry.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Ambientais , Incêndios Florestais , China , Monitoramento Ambiental , Material Particulado/análise
17.
Environ Monit Assess ; 192(7): 460, 2020 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-32594326

RESUMO

Various plant traits are widely utilised to assess environment health. However, non-monotonic responses in plants (hormesis and non-hormetic ones) can induce an incorrect assessment of contamination level because they have maximums and/or minimums. Hence, an increase in the pollution level will not always be accompanied by plant index deteriorations. The frequencies of non-monotonic responses, especially non-hormetic responses, have been insufficiently studied for plant traits. This study analysed the frequencies of non-monotonic changes in plants experiencing urban chemical pollution (B. pendula, T. cordata and T. officinale) and with different pollutant exposures (heavy metals, herbicide glyphosate, formaldehyde and sodium chloride) in experiments (T. aestivum and P. sativum). In the city, we evaluated the traits in plants with the same ontogenetic stages on plots near roads with various traffic and similar abiotic conditions. In urban areas, non-monotonic responses were found in both woody (B. pendula and T. cordata) and herbaceous (T. officinale) species for most traits. Their frequencies corresponded to the proportion of monotonic responses (B. pendula) or were even higher (T. cordata and T. officinale). In studied trees, non-monotonic responses were more common in biochemical traits compared with non-biochemical ones. With experimental pollutant exposure, non-monotonic responses were obtained for most traits of both dicotyledonous (P. sativum) and monocotyledonous (T. aestivum) plants, and their frequency was significantly higher than for monotonic ones. Non-hormetic responses significantly prevailed among non-monotonic changes of plant indexes in the city and experiments. Thus, it is necessary to consider both hormesis and non-hormetic responses to assess correctly environmental quality using plant indexes.


Assuntos
Poluentes Ambientais , Hormese , Cidades , Monitoramento Ambiental , Plantas , Poluição Relacionada com o Tráfego
18.
Chemosphere ; 257: 127137, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32480086

RESUMO

Polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are persistent organic pollutants that have detrimental health effects. As people are exposed to them mainly through the diet, EU has set maximum food dioxin and PCBs levels. EFSA CONTAM Panel made new risk assessment in 2018 that lowered the tolerable weekly intake (TWI) from 14 pg-TEQ/kg bw/week to 2 pg-TEQ/kg bw/week. Critical effect was decreased semen count at the age of 18-19 years if serum total TEQ at the age of 9 years exceeded the No Observed Adverse Effect Level (NOAEL) of 7 pg/g lipid. However, it is largely unknown to what extent NOAEL is exceed in European boys currently. We thus measured PCBs from small volume of serum in 184 Finnish children 7-10 years of age. To estimate the TEQ levels of children from measured PCB levels, we used our existing human milk PCDD/F and PCB concentrations to create a hierarchical Bayesian regression model that was used to estimate TEQs from measured PCBs. For quality control (QC), three pooled blood samples from 18 to 20 year old males were measured for PCDD/Fs and PCBs, and estimated for TEQs. In QC samples measured and estimated TEQs agreed within 84%-106%. In our estimate for 7-10 year old children, PCDD/F TEQ exceeded NOAEL only in 0.5% and total TEQ in 2.7% of subjects. Risk management following the decreased TWI proposed by the CONTAM Panel should be carefully considered if total TEQ in children is already largely below the NOAEL.


Assuntos
Dibenzofuranos Policlorados/sangue , Exposição Ambiental/análise , Poluentes Ambientais/sangue , Dibenzodioxinas Policloradas/sangue , Adolescente , Adulto , Teorema de Bayes , Benzofuranos/análise , Criança , Dibenzofuranos , Dibenzofuranos Policlorados/análise , Dieta , Dioxinas/análise , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Finlândia , Contaminação de Alimentos/análise , Humanos , Leite Humano/química , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análise , Medição de Risco , Adulto Jovem
19.
Chemosphere ; 257: 127199, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32480092

RESUMO

The ever-increasing use of domestic washing machine by urban population is playing a major role in synthetic microfibers (SMFs) pollution via entering the ecosystem. Although many of the sources of fragmented plastic pollution in oceanic environments have been well known, urban areas are playing a major contributor due to huge populations. Thousands of scientific investigations are now reporting the adverse effect of these micro pollutants on aquatic and terrestrial environment, food chain and human health. Microfiber particles along with washing machine grey waters are emitted into urban drainage adjoining the lakes and river which ultimately mix in ocean water and after emission these tiny particles dispersed though out the ocean water by currents due to their low density. Environmental pollution cause by domestic laundering processes of synthetic clothes has been reported as the major cause of primary microplastics in the marine system. While community awareness and improved education will be successful in making public conscious of this problem, there needs to be more research on global scale to mitigate the ecological consequences of microfiber pollution by urban habitats through environmental friendly approach. This paper focuses to improve the understanding of urban population influence on microfiber pollution, their ecological toxicity to aquatic organism and humans, detection and characterization techniques with an emphasis on future research for prevention and control of microfiber pollution.


Assuntos
Monitoramento Ambiental/métodos , Plásticos/toxicidade , Poluentes Químicos da Água/toxicidade , Organismos Aquáticos , Ecossistema , Poluentes Ambientais , Poluição Ambiental , Cadeia Alimentar , Humanos , Lagos , Oceanos e Mares , Rios , Têxteis , Água , Poluentes Químicos da Água/análise
20.
Chemosphere ; 257: 127272, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32534299

RESUMO

A hybrid biofilter was established on Fe-C supported carriers aimed to enhance nitrogen removal from polluted water of low Carbon/Nitrogen (C/N) ratio. Effects of organic loadings, hydraulic retention time (HRT), additional electron donor (Fe2+) supplementation and operation mode on the performance of the biofilter were investigated. Results showed that up-flow operation mode was better than down-flow mode in terms of nitrate and total nitrogen (TN) removal at low COD/N. The average removal of NO3--N, NH4+ -N and TN attained 83.1%, 84.7% and 81.2%, respectively, under the conditions of influent COD/NO3--N = 1.5-3.6, HRT = 10 h and up-flow operation. When the biofilter was operated under autotrophic conditions without organic compounds in influent as electron donors, the biofilter achieved a NO3--N removal of 46% and TN removal of 56% depending on the innate electron donors provided by the Fe-C carriers. Supplementation of Fe2+ in influent further promoted autotrophic denitrifying process, and the removal of NO3--N and TN increased to 96.3% and 84.7%, respectively, at the mol ratio of Fe2+/NO3- = 10 and HRT = 10 h. The microbial community was analyzed for the biofilm samples enriched under heterotrophic and autotrophic conditions. The Fe-C biofilter boosted the growth of a large population of mixotrophic denitrifying bacteria including Gallionella, heterotrophic denitrifying bacteria Denitratisoma, and autotrophic denitrifying bacteria Thiobacillus and Thioalkalispira. On the whole, the biofilter coupled with Fe-C micro-electrolysis provides a novel strategy to treat polluted water of low C/N under both heterotrophic and autotrophic conditions.


Assuntos
Reatores Biológicos/microbiologia , Nitrogênio/metabolismo , Processos Autotróficos , Bactérias , Carbono , Desnitrificação , Poluentes Ambientais , Processos Heterotróficos , Nitratos , Águas Residuárias , Água
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