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1.
N Engl J Med ; 390(10): 900-910, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38446676

RESUMO

BACKGROUND: Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. METHODS: We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. RESULTS: A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 µg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 µg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). CONCLUSIONS: In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).


Assuntos
Doenças das Artérias Carótidas , Microplásticos , Placa Aterosclerótica , Humanos , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/etiologia , Estenose das Carótidas/patologia , Microplásticos/efeitos adversos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Placa Aterosclerótica/química , Placa Aterosclerótica/etiologia , Placa Aterosclerótica/mortalidade , Placa Aterosclerótica/patologia , Plásticos/efeitos adversos , Estudos Prospectivos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/mortalidade , Fatores de Risco de Doenças Cardíacas , Endarterectomia das Carótidas , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/patologia , Doenças das Artérias Carótidas/cirurgia , Seguimentos
2.
Molecules ; 28(10)2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-37241948

RESUMO

In recent years, the discharge of various emerging pollutants, chemicals, and dyes in water and wastewater has represented one of the prominent human problems. Since water pollution is directly related to human health, highly resistant and emerging compounds in aquatic environments will pose many potential risks to the health of all living beings. Therefore, water pollution is a very acute problem that has constantly increased in recent years with the expansion of various industries. Consequently, choosing efficient and innovative wastewater treatment methods to remove contaminants is crucial. Among advanced oxidation processes, electrochemical oxidation (EO) is the most common and effective method for removing persistent pollutants from municipal and industrial wastewater. However, despite the great progress in using EO to treat real wastewater, there are still many gaps. This is due to the lack of comprehensive information on the operating parameters which affect the process and its operating costs. In this paper, among various scientific articles, the impact of operational parameters on the EO performances, a comparison between different electrochemical reactor configurations, and a report on general mechanisms of electrochemical oxidation of organic pollutants have been reported. Moreover, an evaluation of cost analysis and energy consumption requirements have also been discussed. Finally, the combination process between EO and photocatalysis (PC), called photoelectrocatalysis (PEC), has been discussed and reviewed briefly. This article shows that there is a direct relationship between important operating parameters with the amount of costs and the final removal efficiency of emerging pollutants. Optimal operating conditions can be achieved by paying special attention to reactor design, which can lead to higher efficiency and more efficient treatment. The rapid development of EO for removing emerging pollutants from impacted water and its combination with other green methods can result in more efficient approaches to face the pressing water pollution challenge. PEC proved to be a promising pollutants degradation technology, in which renewable energy sources can be adopted as a primer to perform an environmentally friendly water treatment.

3.
J Clin Med ; 12(8)2023 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-37109111

RESUMO

Atopy is an exaggerated IgE-mediated immune response to foreign antigens in which metabolic abnormalities of the leukotrienes (LTs) pathway play a crucial role. Recent studies have described sex as a key variable in LT biosynthesis, partly explaining why treatment with anti-LT drugs in atopic subjects leads to better control of symptoms in women. In addition, variability in LT production is often associated with single nucleotide polymorphisms (SNPs) in the arachidonate 5-lipoxygenase (ALOX5) gene, which encodes the leukotriene-synthesizing enzyme machinery, 5-lipoxygenase (5-LO). This study aimed to investigate whether two SNPs of ALOX5 are implicated in sex differences in allergic diseases in a prospective cohort of 150 age- and sex-matched atopic and healthy subjects. Rs2029253 and rs2115819 were genotyped using allele-specific RT-PCR, and serum levels of 5-LO and LTB4 were measured by ELISA. Both polymorphisms are significantly more common in women than in men, and their influences on LT production vary as a function of sex, leading to a decrease in men's and an increase in women's serum levels of 5-LO and LTB4. These data represent a new resource for understanding sex-related differences in lung inflammatory diseases, partly explaining why women are more likely to develop allergic disorders than men.

4.
Molecules ; 28(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36770973

RESUMO

In the last few years, many industrial sectors have generated and discharged large volumes of saline wastewater into the environment. In the present work, the electrochemical removal of nitrogen compounds from synthetic saline wastewater was investigated through a lab-scale experimental reactor. Experiments were carried out to examine the impacts of the operational parameters, such as electrolyte composition and concentration, applied current intensity, and initial ammoniacal nitrogen concentration, on the total nitrogen removal efficiency. Using NaCl as an electrolyte, the NTOT removal was higher than Na2SO4 and NaClO4; however, increasing the initial NaCl concentration over 250 mg·L-1 resulted in no benefits for the NTOT removal efficiency. A rise in the current intensity from 0.05 A to 0.15 A resulted in an improvement in NTOT removal. Nevertheless, a further increase to 0.25 A led to basically no enhancement of the efficiency. A lower initial ammoniacal nitrogen concentration resulted in higher removal efficiency. The highest NTOT removal (about 75%) was achieved after 90 min of treatment operating with a NaCl concentration of 250 mg·L-1 at an applied current intensity of 0.15 A and with an initial ammoniacal nitrogen concentration of 13 mg·L-1. The nitrogen degradation mechanism proposed assumes a series-parallel reaction system, with a first step in which NH4+ is in equilibrium with NH3. Moreover, the nitrogen molar balance showed that the main product of nitrogen oxidation was N2, but NO3- was also detected. Collectively, electrochemical treatment is a promising approach for the removal of nitrogen compounds from impacted saline wastewater.

5.
Pharmaceuticals (Basel) ; 15(10)2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36297323

RESUMO

Asthma is characterized by chronic inflammation and a variable degree of airway hyperresponsiveness (AHR). Our previous papers documented a role for Nociceptin/Orphanin FQ (N/OFQ) and its receptor N/OFQ peptide (NOP) in AHR. Therefore, the aim of this study was to improve the bioavailability of N/OFQ by developing solid lipid nanoparticles (SLNs). N/OFQ-loaded SLNs were prepared by the Quasi Emulsion Solvent Diffusion (QESD) technique and then characterized. Brown Norway rats were sensitized to ovalbumin (OVA) and treated with an intratracheal administration of saline solution or N/OFQ-SLN. Then, 24 h after the last challenge, functional histological and molecular evaluations were performed. SLNs showed a mean diameter of 233 ± 0.03 nm, a polydispersity index (PDI) value around 0.28 ± 0.02 and a drug release percentage of 84.3. The in vitro release of N/OFQ from SLNs showed that the release of the peptide starts already after two hours of incubation. Animals receiving N/OFQ-SLN showed a significative decrease in allergen-induced AHR compared to the control group. These results showed the positive effects of N/OFQ-SLNs on the inflammatory process and on the mechanical properties of the airways, suggesting that the innovative nanotechnological approach may be therapeutically beneficial for asthmatic patients.

6.
J Clin Med ; 11(18)2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36143090

RESUMO

BACKGROUND: Bronchial asthma is an inflammatory airway disease with an ever-increasing incidence. Therefore, innovative management strategies are urgently needed. MicroRNAs are small molecules that play a key role in lungs cellular functions and are involved in chronic inflammatory diseases, such as bronchial asthma. This study aims to compare microRNA serum expression between subjects with asthma, obesity, the most common co-morbidity in asthma, and healthy controls to obtain a specific expression profile specifically related to lung inflammation. METHODS: We collected serum samples from a prospective cohort of 25 sex-matched subjects to determine circulating miRNAs through a quantitative RT-PCR. Moreover, we performed an in silico prediction of microRNA target genes linked to lung inflammation. RESULTS: Asthmatic patients had a significant lower expression of hsa-miR-34a-5p, 181a-5p and 146a-5p compared to both obese and healthy ones suggesting microRNAs' specific involvement in the regulation of lungs inflammatory response. Indeed, using in silico analysis, we identified microRNAs novel target genes as GATA family, linked to the inflammatory-related pathway. CONCLUSIONS: This study identifies a novel circulating miRNAs expression profile with promising potentials for asthma clinical evaluations and management. Further and larger investigations will be needed to confirm the potential role of microRNA as a clinical marker of bronchial asthma and eventually of pharmacological treatment response.

7.
Molecules ; 25(4)2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32092867

RESUMO

Humic acids (HA) are promising green materials for water and wastewater treatment. They show a strong ability to sorb cationic and hydrophobic organic pollutants. Cationic compounds interact mainly by electrostatic interaction with the deprotonated carboxylic groups of HA. Other functional groups of HA such as quinones, may form covalent bonds with aromatic ammines or similar organic compounds. Computational and experimental works show that the interaction of HA with hydrophobic organics is mainly due to π-π interactions, hydrophobic effect and hydrogen bonding. Several works report that sorbing efficiency is related to the hydrophobicity of the sorbate. Papers about the interaction between organic pollutants and humic acids dissolved in solution, in the solid state and adsorbed onto solid particles, like aluminosilicates and magnetic materials, are reviewed and discussed. A short discussion of the thermodynamics and kinetics of the sorption process, with indication of the main mistakes reported in literature, is also given.


Assuntos
Substâncias Húmicas , Poluentes do Solo/química , Adsorção , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas
8.
Environ Sci Pollut Res Int ; 25(27): 26831-26836, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29468388

RESUMO

The sorption of some benzene derivatives: o-xylene, toluene, phenol, benzyl alcohol, resorcinol and hydroquinone onto a zeolitic tuff-humic acid adduct (PCT-ImHA) was analysed by batch technique at 25 °C and neutral pH. PCT-ImHA was prepared by binding leonardite-extracted humic acids (HA) to a zeolitic tuff sample rich in phillipsite and chabazite and enriched with Ca2+ by cation exchange (Ca-PCT). The HA calcium salts were gently mixed with wet Ca-PCT; then, the mixture was heated at 330 °C for 1.5 h. An adduct with almost 2% of HA was obtained. The experimental data were well fitted by the Langmuir adsorption isotherm and showed that saturation capacity (qMax) increased with the octanol-water repartition coefficient (KO-W). The comparison with previous data on sorption onto immobilised HA highlights that qMax values for PCT-ImHA are far higher than the sum of the contributions of the two separate components.


Assuntos
Derivados de Benzeno/química , Substâncias Húmicas , Purificação da Água/métodos , Zeolitas/química , Adsorção , Concentração de Íons de Hidrogênio , Minerais , Fenol , Fenóis , Tolueno , Xilenos
9.
Environ Sci Pollut Res Int ; 23(22): 22993-23004, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27581046

RESUMO

The advanced treatment of polluted liquid streams containing traces of pharmaceutical compounds is a major issue, since more and more effluents from pharma labs and wastewaters containing the excretions of medically treated humans and animals are discharged in the conventional wastewater treatment plants without previous effective treatments. Ibuprofen is a widely used non-steroidal anti-inflammatory drug (NSAID), which explains why it is found in wastewaters so often. In this paper, the removal of IBP from simulated water streams was investigated by using a lab-scale experimental device, consisting of a batch reactor equipped with a lamp emitting monochromatic UV light at a fixed wavelength (254 nm) and various intensities. Three sets of experiments were carried out: the first to study IBP concentration as a function of time, at different volumes of treated solutions (V = 10-30 mL); the second to explore the effect of pH on IBP degradation as a function of time (pH = 2.25-8.25) and the third to evaluate the effect of different UV light intensities on IBP degradation (E = 100-400 mJ m-2). The IBP initial concentration (IBP 0) was varied in the range 30-60 mg L-1. The results obtained show that the concentration of IBP decreases along with treatment time, with a negative effect of the treated volume, i.e. smaller volumes, such as lower liquid heights, are more easily degraded. Moreover, the higher the pH, the better the IBP degradation; actually, when pH increases from 2.25 to 6.6 and 8.25, the IBP concentration, after an hour of treatment, decreases respectively to 45, 34 and 27 % of its initial value. In addition, as the intensity of light increases from 100 to 400 mJ m-2, the IBP concentration decreases to 34 % of its initial value. A reaction scheme is put forward in the paper, which well describes the effects of volume, pH and light intensity on the IBP degradation measured experimentally. Moreover, the IBP degradation by-products have been identified.


Assuntos
Anti-Inflamatórios não Esteroides/química , Ibuprofeno/química , Fotólise , Soluções , Raios Ultravioleta , Água/química
10.
Environ Monit Assess ; 188(9): 499, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27485615

RESUMO

The Second-order Closure Integrated Puff (SCIPUFF) model was used to study the impact on urban air quality caused by two cement plants emissions located near the city of Caserta, Italy, during the entire year of 2015. The simulated and observed PM10 concentrations were compared using three monitoring stations located in urban and sub-urban area of Caserta city. Both simulated and observed concentrations are shown to be highest in winter, lower in autumn and spring and lowest in summer. Model results generally follow the pattern of the observed concentrations but have a systematic under-prediction of the concentration values. Measures of the bias, NMSE and RMSE indicate a good correlation between observed and estimated values. The SCIPUFF model data analysis suggest that the cement plants are major sources for the measured PM10 values and are responsible for the deterioration of the urban air quality in the city of Caserta.


Assuntos
Poluentes Atmosféricos/análise , Materiais de Construção , Monitoramento Ambiental/métodos , Modelos Teóricos , Material Particulado/análise , Ar/análise , Ar/normas , Cidades , Itália , Estações do Ano
11.
Ultrason Sonochem ; 29: 76-83, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26584987

RESUMO

Ibuprofen (IBP) is an anti-inflammatory drug whose residues can be found worldwide in natural water bodies resulting in harmful effects to aquatic species even at low concentrations. This paper deals with the degradation of IBP in water by hydrodynamic cavitation in a convergent-divergent nozzle. Over 60% of ibuprofen was degraded in 60 min with an electrical energy per order (EEO) of 10.77 kWh m(-3) at an initial concentration of 200 µg L(-1) and a relative inlet pressure pin=0.35 MPa. Five intermediates generated from different hydroxylation reactions were identified; the potential mechanisms of degradation were sketched and discussed. The reaction pathways recognized are in line with the relevant literature, both experimental and theoretical. By varying the pressure upstream the constriction, different degradation rates were observed. This effect was discussed according to a numerical simulation of the hydroxyl radical production identifying a clear correspondence between the maximum kinetic constant kOH and the maximum calculated OH production. Furthermore, in the investigated experimental conditions, the pH parameter was found not to affect the extent of degradation; this peculiar feature agrees with a recently published kinetic insight and has been explained in the light of the intermediates of the different reaction pathways.


Assuntos
Hidrodinâmica , Ibuprofeno/química , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Ibuprofeno/isolamento & purificação , Cinética , Pressão , Termodinâmica , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água
12.
J Environ Sci Health B ; 49(8): 578-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24901961

RESUMO

The sorption kinetics of simazine (6-chloro-N,N'-diethyl-1,3,5-triazine-2,4-diamine), imidacloprid (1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine), and boscalid (2-chloro-N-(4'-chlorobiphenyl-2-yl)nicotinamide), three pesticides of wide use in agriculture, was determined in five different water/soil systems over a time interval from the initial few seconds to about 1 month. In all the experiments, sorption kinetics showed a biphasic pattern characterized by an initial, relatively short phase with a high sorption rate and a later phase with much a lower sorption rate. Initial sorption capacity increased with soil organic carbon content and with sorbate hydrophobicity. We postulate that the first phase of the process involves a fast second-order sorption reaction on superficial sites of soil particles, whereas the second phase depends on diffusion-controlled migration to internal binding sites. A kinetic equation based on this hybrid model accurately fitted all data sets. Less satisfactory results were obtained employing the pseudo-first order, pseudo-second order, Elovich, two site non-equilibrium, or Weber-Morris equation. The superior performance of the hybrid model for describing boscalid sorption probably reflects the high hydrophobic character and consequent low diffusion rates of this compound. The accuracy of modelling was in any case strongly dependent on the time interval considered.


Assuntos
Compostos de Bifenilo/química , Imidazóis/química , Niacinamida/análogos & derivados , Nitrocompostos/química , Praguicidas/química , Simazina/química , Adsorção , Agricultura , Cromatografia Líquida de Alta Pressão , Fungicidas Industriais/química , Herbicidas/química , Inseticidas/química , Modelos Teóricos , Neonicotinoides , Niacinamida/química , Fatores de Tempo
13.
Environ Sci Pollut Res Int ; 21(23): 13169-74, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24136577

RESUMO

PM10 levels have been recorded in the suburban area of Caserta (Italy) from February to October 2012. The daily limit was exceeded in 13 % of the determinations, with no significant difference between weekdays and weekends. Benzo[a]pyrene concentrations were in the range 0.01-0.46 ng/m(3), thus, never exceeding the National Standard. The B(a)P-eq was 0.20 ng/m(3). PM10 peaks were associated with wind from east-northeast. The same was observed for Ca concentrations, whereas no relation with wind direction was observed for organic pollutants. The results point to a local limestone quarry and cement factory as the likely major source of PM10 pollution in the area investigated.


Assuntos
Poluentes Atmosféricos/análise , Material Particulado/análise , Monitoramento Ambiental , Humanos , Itália , Estações do Ano , População Suburbana , Emissões de Veículos/análise
14.
Chemosphere ; 95: 75-80, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24206836

RESUMO

Sorption isotherms from water solutions for toluene, cyclohexane, o-xylene, benzyl alcohol, phenol and cyclohexanol onto a humic acid-zeolite adduct were determined at 4, 14, 24 and 34 °C and utilized to calculate the isosteric enthalpy (ΔadsHi) and isosteric entropy (ΔadsSi) of the process. For hydrocarbon compounds, toluene, cyclohexane and o-xylene, both ΔadsHi and ΔadsSi were negative, the process was exothermic. In contrast, for hydroxyl compounds, benzyl alcohol, phenol and cyclohexanol, ΔadsHi and ΔadsSi were positive, the increase in entropy possibly reflecting the release of water molecules during sorption. The results suggest that sorption/desorption of either class of compounds could be controlled by operating on the temperature.


Assuntos
Substâncias Perigosas/química , Substâncias Húmicas , Poluentes Químicos da Água/química , Zeolitas/química , Adsorção , Modelos Químicos , Termodinâmica
16.
Environ Monit Assess ; 150(1-4): 437-44, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18437518

RESUMO

Atmospheric BTEX [benzene, toluene, ethylbenzene, o-xylene and (m + p)-xylene] concentrations have been determined in the Naples metropolitan area (NMA) and in two suburban areas located on the north within about 25 km, during 2006. The pollutants were collected by passive samplers (24-h samplings), and analysed by GC-MS. In all the areas analysed the average atmospheric benzene concentrations were higher than the limit value fixed by the European Union for 2010 and in NMA the average concentration (9.8 microg m(-3)) also exceeded the limit fixed for 2006. High linear correlation coefficients between the average daily concentrations of the different BTEX are indicative of a single major source, most likely the vehicular traffic. The temporal and spatial distribution of BTEX relative concentrations suggest that massive emissions in NMA negatively affect the quality of the air in northern suburban areas, prevalently during the hottest months of the year, probably due to transport by local seasonal winds. The ratios between BTEX daily concentrations showed a clear dependence on the intensity of solar actinic flow, indicating a major role of photochemical processes in the air cleaning from these volatile organic pollutants.


Assuntos
Poluentes Atmosféricos/análise , Atmosfera , Derivados de Benzeno/análise , Benzeno/análise , Cidades , Tolueno/análise , Xilenos/análise , Monitoramento Ambiental , Humanos , Itália , Saúde da População Urbana , Vento
17.
Chemosphere ; 73(4): 614-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18640696

RESUMO

The atmospheric concentrations of benzene, toluene, ethylbenzene and isomeric xylenes (BTEX) in a medium-sized town (S. Maria Capua Vetere, about 32000 inhabitants, Southern Italy) have been determined during working days and weekends in 2006. The procedure used was 24h passive adsorption by samplers distributed throughout the town followed by GC/MS analysis. On a yearly base, the arithmetic mean benzene concentrations were above the limit required by the 2000/69/CE European Directive. The Pearson correlation coefficients of the 24h geometric mean BTEX concentrations were indicative of stationary sources of toluene located in a well circumscribed area of the urban territory, active only during the working days and not officially recognized. The results highlight the effectiveness of the statistical approach used in this study for the identification of pollutant sources.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Interpretação Estatística de Dados , Monitoramento Ambiental/estatística & dados numéricos , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Itália , Xilenos/análise
18.
Pest Manag Sci ; 64(7): 768-74, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18318456

RESUMO

BACKGROUND: Although biodegradation seems to be the main cause of herbicide degradation, abiotic degradation can also be important for chemicals such as phenylureas, which are subject to catalysed soil reactions. The aim of this work is to investigate the effect of dissolved humic acids (HAs), normally present in natural waters, on the hydrolysis of phenylurea herbicides, and it presents a kinetic model that takes into account the role of adsorption. RESULTS: The linearity of the adsorption isotherms indicates that phenylurea-humic acid interaction can be considered in terms of a repartition-like equilibrium of phenylurea between water and HAs. Kinetic experiments show that the degradation rates of phenylureas increase with HA concentration. CONCLUSION: The kinetic equation adopted adequately describes the experimental data trend, allowing the evaluation of the catalytic effect of HAs on the chemical degradation of phenylureas. Carboxyl groups of HAs seem to play a leading role in the catalysis. The kinetic equation derived in this work could be helpful in predicting the persistence of phenylureas and of related compounds in natural water.


Assuntos
Herbicidas/metabolismo , Substâncias Húmicas/análise , Compostos de Fenilureia/metabolismo , Biodegradação Ambiental , Herbicidas/química , Cinética , Compostos de Fenilureia/química , Poluentes do Solo/química , Poluentes do Solo/metabolismo
19.
Ann Chim ; 97(8): 597-604, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17899874

RESUMO

Background atmospheric levels of aldehydes, BTEX and PM10 pollutants were measured in the suburb of Caserta (Italy), 75 thousands inhabitants, 41degrees 04' N, on rainless weekdays and weekends during 2005. On weekdays the average daily concentrations (microg m(-3)) were 41.6 PM10, 8.6 benzene, 25.2 toluene, 6.3 ethylbenzene, 14.0 (m+p)-xylene, 11.7 o-xylene, 6.5 formaldehyde, 3.3 acetaldehyde. All the pollutant concentrations were strictly correlated (mean correlation coefficients = 0.90). At weekends the concentrations were lower by about 1.6 times. Both on weekdays and at weekends the PM10 and benzene levels exceeded the limits set by the EU Directive 30/1999 and 69/2000, respectively.


Assuntos
Poluentes Atmosféricos/análise , Aldeídos/análise , Derivados de Benzeno/análise , Material Particulado/análise , Benzeno/análise , Monitoramento Ambiental , Itália , Estações do Ano , Fatores de Tempo , Tolueno/análise , Emissões de Veículos , Xilenos/análise
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