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1.
J Environ Sci (China) ; 133: 118-137, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37451782

RESUMO

The chemical composition of PM2.5 at two sites in Lebanon, a country in the East Mediterranean - Middle East region, is investigated in the spring and summer seasons. The average PM2.5 concentrations were of (29 ± 16) µg/m3 for Beirut urban site and (32 ± 14) µg/m3 for Beirut suburban site. This study showed that the geographic location of the East Mediterranean region, such as its proximity to the Mediterranean Sea and the dust storm intrusion are a significant contributor to the high PM levels from natural sources, which cannot be mitigated, rendering the PM2.5 WHO annual Air Quality guideline unattainable due to high natural background, which also applies to the entire Middle East region. Turkey and Eastern Europe are the dominant origin of air masses throughout our sampling days, suggesting the long-range transport as an important potential contributor to the high observed concentrations of V, Ni, and sulfate in this region most probably in other East Mediterranean countries than Lebanon too. Main local sources determined through the chemical speciation including organics are road transport, resuspension of dust and diesel private generators. A health risk assessment of airborne metals was performed and the carcinogenic risk for all the metals exceeded by 42 (adults) and 14 (children) times the acceptable risk level (10-6) at both sites. Vanadium was the predominant carcinogenic metal, emphasizing the need to replace energy production with cleaner energy on a regional level and highlighting the severe impact of air pollution on the health of inhabitants in this region's main cities.


Assuntos
Poluentes Atmosféricos , Adulto , Criança , Humanos , Poluentes Atmosféricos/análise , Cidades , Emissões de Veículos/análise , Líbano , Monitoramento Ambiental , Poeira/análise , Estações do Ano , Material Particulado/análise
2.
Chemosphere ; 183: 69-79, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28535463

RESUMO

Dilovasi is one of the heavily industrialized areas in Turkey with serious environmental problems. In this study, the atmospheric concentration of PAHs and PCBs were measured for a whole year at 23 sites. The average ambient air Σ15PAH and Σ41PCB concentrations were found as 285 ± 431 ng m-3 and 4152 ± 6072 pg m-3, respectively. PAH concentrations increased with decreasing temperature especially in urban areas, indicating the impact of residential heating. However, PCB concentrations mostly increased with temperature probably due to enhanced volatilization from their sources. The gradient obtained for PCBs, rural < suburban < urban < industrial/urban, is more clear than those obtained for PAHs. The average Σ15PAH and Σ41PCB soil concentrations were found as 992 ± 1323 and 18.8 ± 32.0 µg kg-1, respectively. PCB soil concentrations did not show significant temporal variations while PAH concentrations were variable especially for urban areas. The volatilization tendencies of low and medium molecular weight PAHs from soil to air were higher in industrial-urban areas than rural sites, showing that soil was a secondary source for PAHs. Fugacity ratios of PCBs were mostly <1.0 for the whole sampling period. Although the source/sink tendency of soil for some PCBs depends on their volatility, considering the whole data, PCBs were generally deposited to soil.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Indústrias , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Ar/análise , Solo/química , Turquia , Urbanização , Volatilização
3.
Environ Sci Pollut Res Int ; 24(10): 9515-9529, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28238182

RESUMO

Particulate matter (PM) measurements were conducted during heating corn oil, heating corn oil mixed with the table salt and heating low fat ground beef meat using a PTFE-coated aluminum pan on an electric stove with low ventilation. The main objectives of this study were to measure the size segregated mass concentrations, emission rates, and fluxes of 24 trace elements emitted during heating cooking oil or oil with salt and cooking meat. Health risk assessments were performed based on the resulting exposure to trace elements from such cooking activities. The most abundant elements (significantly different from zero) were Ba (24.4 ug m-3) during grilling meat and Ti during heating oil with salt (24.4 ug m-3). The health assessment indicates that the cooking with an electric stove with poor ventilation leading to chronic exposures may pose the risk of significant adverse health effects. Carcinogenic risk exceeded the acceptable level (target cancer risk 1 × 10-6, US EPA 2015) by four orders of magnitude, while non-carcinogenic risk exceeded the safe level (target HQ = 1, US EPA 2015) by a factor of 5-20. Cr and Co were the primary contributors to the highest carcinogenic and non-carcinogenic risks, respectively.


Assuntos
Material Particulado , Oligoelementos , Poluição do Ar em Ambientes Fechados , Culinária , Humanos , Medição de Risco
4.
Environ Res ; 154: 101-108, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28056405

RESUMO

Characterization of the airborne particulate matter (PM) emitted from cooking components including cooking oil, and additives like salt has not been carefully investigated. This study provides new data on the concentration, composition, and emission rates/fluxes of PM (less than 3.3µm) generated during heating corn oil and corn oil with added table salt. The concept of emission flux was employed to estimate the emission rates in this study. A statistically significant reduction of 47.6% (P<0.05) in the total PM emission rate and emission flux were observed when salt was added to the heated corn oil (5.15×101mgmin-1) compared to the pure oil (9.83×101mgmin-1). The OC emission rate decreased 61.3% (P<0.05) when salt was added to the corn oil (2.35×101mgmin-1) compared to the pure corn oil (5.83×101mgmin-1). With the salt, the total EC emission rate was 6.99×10-1mgmin-1, a 62.7% reduction in EC emission compared to pure corn oil (1.88mgmin-1). These results suggest that table salt can be added to the corn oil prior to frying to reduce exposure to cooking generated PM.


Assuntos
Culinária/métodos , Óleo de Milho/química , Material Particulado/química , Metais/análise , Tamanho da Partícula , Material Particulado/análise , Cloreto de Sódio/química
5.
Environ Pollut ; 220(Pt B): 1322-1332, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27825846

RESUMO

Istanbul, one of the mega cities in the world located between Asia and Europe, has suffered from severe air pollution problems due to rapid population growth, traffic and industry. Atmospheric levels of PAHs and PCBs were investigated in Istanbul at 22 sampling sites during four different sampling periods using PUF disk passive air samplers and spatial and temporal variations of these chemicals were determined. Soil samples were also taken at the air sampling sites. At all sites, the average ambient air Σ15PAH and Σ41PCB concentrations were found as 85.6 ± 68.3 ng m-3 and 246 ± 122 pg m-3, respectively. Phenanthrene and anthracene were the predominant PAHs and low molecular weight congeners dominated the PCBs. The PAH concentrations were higher especially at urban sites close to highways. However, the PCBs showed moderately uniform spatial variations. Except four sites, the PAH concentrations were increased with decreasing temperatures during the sampling period, indicating the contributions of combustion sources for residential heating, while PCB concentrations were mostly increased with the temperature, probably due to enhanced volatilization at higher temperatures from their sources. The results of the Factor Analysis represented the impact of traffic, petroleum, coal/biomass and natural gas combustion and medical waste incineration plants on ambient air concentrations. A similar spatial distribution trend was observed in the soil samples. Fugacity ratio results indicated that the source/sink tendency of soil for PAHs and PCBs depends on their volatility and temperature; soil generally acts as a source for lighter PAHs and PCBs particularly in higher temperatures while atmospheric deposition is a main source for higher molecular weight compounds in local soils. Toxicological effect studies also revealed the severity of air and soil pollution especially in terms of PAHs in Istanbul.


Assuntos
Poluentes Atmosféricos/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Poluentes Atmosféricos/química , Cidades , Monitoramento Ambiental , Combustíveis Fósseis , Calefação , Humanos , Incineração , Resíduos de Serviços de Saúde , Bifenilos Policlorados/química , Hidrocarbonetos Policíclicos Aromáticos/química , Medição de Risco , Solo/química , Poluentes do Solo/química , Turquia , Emissões de Veículos , Volatilização
6.
Environ Sci Pollut Res Int ; 23(14): 14157-72, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27048328

RESUMO

Coarse (particulate matter (PM)2.5-10) and fine (PM2.5) fraction of PM samples were collected between December 2014 and February 2015 at an urban sampling site located at the Bolu plain, of the western Black Sea region of Turkey. The collected samples were analyzed in terms of metals (Al, As, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, Pb, S, Si, Ti, V, and Zn); elemental carbon (EC); and organic carbon (OC). Elevated concentrations measured in this wintertime study were ∼7.8 µg/m(3) in sum of PM2.5-10 and PM2.5 for SO4 (2-) and ∼59.9 µg/m(3) in PM2.5 for OC. The contributions of primary and secondary OC (POC and SOC, respectively) to total OC mass were 60 and 40 %, respectively, while contribution of SOC to OC increased by up to 74 % in stable atmospheric conditions. The significantly high OC/EC ratio (∼10.1) found in this study relative to other wintertime studies was attributed to increased emissions from residential heating and lower mixing height observed during the study. Two and three factors were resolved by factor analysis for PM2.5-10 and PM2.5, respectively. Two Saharan dust episodes were observed on 31 January and 1 February, during which crustal PM components such as Mg, Si, and Al increased as much as three times their background concentrations.


Assuntos
Carbono/química , Cidades/estatística & dados numéricos , Material Particulado/química , Tempo (Meteorologia) , África do Norte , Poluentes Atmosféricos/análise , Mar Negro , Carbono/análise , Poeira/análise , Monitoramento Ambiental , Análise Fatorial , Metais/análise , Tamanho da Partícula , Material Particulado/análise , Turquia
7.
Clin Biochem ; 38(9): 792-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16005452

RESUMO

OBJECTIVES: To evaluate the diagnostic significance of serum cystatin C levels in clinical practice. DESIGN AND METHODS: Serum (99m)Tc-DTPA clearance was compared with serum cystatin C, creatinine, beta(2)-microglobulin levels and creatinine clearance in a group of patients aged 42.61 +/- 7.55 years with glomerular filtration rates of 10-60 mL/min/1.73 m(2) (n = 52) and healthy controls aged 43.90 +/- 12.06 years (n = 52). RESULTS: No effect of sex on serum cystatin C levels was observed, but average levels increased with age. No significant difference was evident between the mean cystatin C levels of three blood samples taken at 1 month intervals from healthy subjects. Reference clearance was correlated with creatinine clearance (r = 0.957), cystatin C (r = 0.828), beta(2)-microglobulin (r = 0.767) and creatinine (r = 0.682). 60 mL/min/1.73 m(2) was chosen as the borderline for receiver-operating characteristics analysis. The values for the cut-off point, sensitivity, specificity and the area under curve were determined for cystatin C as 1.36 mg/L, 98%, 99% and 0.99 +/- 00.1, respectively; for creatinine, the values were 103 micromol/L, 80%, 100% and 0.97 +/- 0.01, respectively, and for beta(2)-microglobulin, the values were 2.51 mg/L, 86%, 92% and 0.94 +/- 0.02, respectively. CONCLUSION: Serum cystatin C level can be used as a marker for renal damage.


Assuntos
Cistatinas/sangue , Nefropatias/sangue , Nefropatias/fisiopatologia , Rim/fisiopatologia , Adulto , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Creatinina/sangue , Cistatina C , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Estatísticas não Paramétricas , Pentetato de Tecnécio Tc 99m
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