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1.
Environ Monit Assess ; 195(1): 180, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36480108

RESUMO

A simple, versatile, and economical method development with matrix elimination to determine the elements As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn in seawater by using the technique of inductively coupled plasma mass spectrometry is reported. Real seawater was used as a matrix for the standard adding calibration and other validation parameters. The samples were open digested at 80 °C with 2 mL HNO3 and 0.25 mL HF under the hood. A two-step digestion procedure was applied, and the volume was completed to 10 mL with deionized water. Chloride removal was accomplished by using this procedure. The concentrations of Ca and Mg ions were lessened by 15% and 20%, respectively. These results were verified with ion chromatography, SEM-EDS, and mass difference analyses. It was observed that there was a 40% loss in the average mass of particulate matter on the filter media after applying the two-step digestion procedure. Recovery and trueness values were in the range of 86 and 109%. The average precision amounts for elements were determined as RSD (%) in the range of 1.0% and 3.4%. The concentrations of elements determined in the 18 samples collected from the Konyaalti Beach located in Antalya were higher than the maximum allowable concentrations of the Directive 2013/39/EU.


Assuntos
Monitoramento Ambiental
2.
Environ Sci Pollut Res Int ; 29(35): 53569-53583, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35288854

RESUMO

Atmospheric pollutants including ozone, nitrogen dioxide, sulfur dioxide, and BTEX (benzene, toluene, ethylbenzene, and xylenes) compounds were evaluated concerning their spatial distribution, temporal variation, and health risk factor. Bolu plateau where sampling was performed has a densely populated city center, semi-rural areas, and forested areas. Additionally, the ozone formation potentials of BTEXs were calculated, and toluene was found to be the most important compound in ground level ozone formation. The spatial distribution of BTEXs and nitrogen dioxide pollution maps showed that their concentrations were higher around the major roads and city center, while rural-forested areas were found to be rich in ozone. BTEXs and nitrogen dioxide were found to have higher atmospheric concentrations in winter. That was mostly related to the source strength and low mixing height during that season. The average toluene to benzene ratios demonstrated that there was a significant influence of traffic emissions in the region. Although there was no significant change in sulfur dioxide concentrations in the summer and winter seasons of 2017, the differences in the spatial distribution showed that seasonal sources such as domestic heating and intensive outdoor barbecue cooking were effective in the atmospheric presence of this pollutant. The lifetime cancer risk through inhalation of benzene was found to be comparable with the limit value (1 × 10-6) recommended by USEPA. On the other hand, hazard ratios for BTEXs were found at an acceptable level for different outdoor environments (villages, roadside, and city center) for both seasons.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , Benzeno/análise , Derivados de Benzeno/análise , Monitoramento Ambiental , Dióxido de Nitrogênio , Ozônio/análise , Dióxido de Enxofre , Tolueno/análise , Turquia , Xilenos/análise
3.
Environ Res ; 204(Pt D): 112399, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34800531

RESUMO

Our study implies the importance of exhaust and non-exhaust emissions in a highway road tunnel, which is crucial to assess their impacts on air quality, human health, climate and developing functional methods for controlling. The total suspended particulates (TSP) and road dust (RD) samples were collected by PUF samplers and manually sweeping, respectively. Campaigns were performed in the summer and winter of 2014 in a highway road tunnel in Bolu, Turkey. Chemical analyses were presented to characterize the contents of organic carbon (OC) fractions (OC1,2,3,4), elemental carbon (EC) fractions (EC1,2,3,4,5,6), polycyclic aromatic hydrocarbons (PAHs) and metals (Al, Ba, Ca, Cu, Mg, Mn, Pb, Sr, Cr and Fe) in the collected TSP and RD samples. Positive matrix factorization (PMF) and orthogonal (Deming) regression analysis were applied to find out the exhaust and non-exhaust vehicle emissions of metal and carbonaceous species in the tunnel. The results showed that the identified source profiles included resuspended road dust (43%), non-exhaust emissions (37%), diesel exhaust emissions (13%), and gasoline exhaust emissions (7%). The relationship between emission markers of metal species and EC carbon fractions was supported by correlation studies. Among these EC fractions, EC4 and EC2 were the most abundant fractions in aerosol and RD samples, respectively and so they highly represented the diesel and non-exhaust emissions. Besides, the EC1 fraction was the indicator of gasoline-fueled emissions. Lower EC1 and higher soot-EC contribution obtained in tunnel aerosol (AS) samples showed the dominance of diesel-fueled vehicles in the tunnel. The data represented herein would help to identify the characteristic of vehicle emissions.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , Carbono/análise , Monitoramento Ambiental/métodos , Humanos , Material Particulado/análise , Emissões de Veículos/análise
4.
Sci Total Environ ; 731: 139201, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32402909

RESUMO

Total of 69 volatile organic compounds (VOCs) including both biogenic (isoprene, monoterpenes and oxygenated compounds) and anthropogenic ones were investigated in Bolu plateau by passive sampling technique. The main objective of this study was to determine spatial distributions, seasonal variations and possible sources for a wide variety of VOCs. Two-week passive sampling campaigns were performed in the winter and summer of 2017. Anthropogenic VOCs were predominant with a high percentage of contribution, 91% and 69% for winter and summer, respectively. Relatively higher concentrations of biogenic VOCs during the summer campaign were found to be related to higher solar intensity, temperature and amount of broad-leaved tree species. Benzaldehyde, toluene, phenol, benzene, hexane, decanal, benzothiazole, dodecane and acetophenone were anthropogenic VOCs with higher concentrations. Among biogenic VOCs, hexanal, alpha-pinene and limonene were found to be in higher concentrations. Spatial distribution maps were drawn for each VOC. Elevated concentrations of VOCs around the city center and major roads indicate that emissions from domestic heating activities and vehicular emissions can be significant sources of VOCs. The results were also supported by Positive Matrix Factorization (PMF) analyses and G-score distribution maps. Solvent evaporation, wood-coal combustion, biogenic emissions (pine, grain, grass), city atmosphere (styrene emissions from plastic production), biogenic (hornbeam, pine, juniper) and vehicle emissions were the identified as the primary VOC sources in Bolu plateau, contributing 31%, 22%, 8.0%, 8.0%, 13%, and 18%, respectively to the total VOC concentrations.

5.
Sci Total Environ ; 723: 138028, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32229382

RESUMO

To study the intraday and interday patterns and possible sources of volatile organic compounds (VOCs), 6-h active sampling was performed in April, May, June, July, and August 2017 and in January 2018 in a semi-urban site in Bolu, Turkey. Totally 69 VOCs having biogenic (BVOCs, i.e., isoprene, monoterpenes and oxygenated VOCs) and anthropogenic origins (AVOCs) were examined. Fifty-four of sixty-nine analyzed VOCs could be detected. Decanal followed by benzaldehyde, benzene, phenol, and toluene were detected as the leading anthropogenic VOCs whereas alpha-pinene and hexanal were the dominant biogenic VOCs. There was a decrease in concentrations of most of the VOCs in January and April when light intensity and temperature were relatively low. Atmospheric levels of total biogenic VOCs exceeded that of anthropogenic VOCs in all months except for January and April. Dependence of biogenic VOC emissions on the light intensity, temperature and the increase in leaves were considered to be effective in their higher levels in summer and daytime periods. The daytime anthropogenic VOCs concentrations were higher than the nighttime anthropogenic VOCs probably due to intense vehicle traffic during working hours and/or increased volatilization from their sources at elevated temperatures. The VOCs that significantly and negatively correlated with ozone were evaluated as effective BVOCs in the ozone formation while the maximum incremental reactivity (MIR) method gave the contribution of AVOCs. Positive Matrix Factorization (PMF) was applied for the source apportionment. G score graphs and G score pollution roses were also used to identify possible sources of investigated VOCs. Solvent evaporation, gasoline-powered vehicle emissions, fossil fuel (residential heating), biogenic (hornbeam, grass, oak, beech) emissions, diesel/domestic activities and forested city atmosphere were identified as the possible VOC sources in the study area.

6.
Heliyon ; 5(7): e02138, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31384684

RESUMO

As known, marine dredged materials (DMs) are highly nuisance wastes if they are not correctly reused or removed. In this work, the usability of DMs to the technical terms as manufactured topsoil (MT) in the urban landscaping works is discussed. Firstly, the leaching potentials of DMs were determined according to the related legislations to identify their hazardousness features. Secondly, DMs were subject to some treatment stages such as sieving, desalination, organic amelioration via peat and sheep manure, and pH adjustment to turn into an alternative natural soil pursuant to the British Standard in the scope of soil quality improvement studies as there is not any national standard in Turkey for the production of topsoil from different materials. Then, MT mixtures were prepared with washed and unwashed DM, peat and sheep manure in different mixing ratios (v/v); 33%, 50% and 67% DM, respectively. Consequently, high quality grass seed mixtures used for the landscaping applications were monitored for six months. The results demonstrate the availability of DM as alternative MT in the urban landscaping areas. Thus, important data were obtained as to the use of DM at alternative areas such as green city, green roof, shopping centers, organized industry, etc.

7.
Environ Monit Assess ; 187(3): 94, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25663404

RESUMO

In this study, a total of 75 water samples (38 groundwater and 37 surface water samples) and 54 surface soil samples were collected from the five districts of Bolu, which is located in the Western Black Sea Region of Turkey in the summer season of 2009. In the autumn season, 17 water samples (surface water and groundwater samples) and 17 soil samples were collected within the city center to observe the seasonal changes of organochlorine pesticides (OCPs). Groundwater and surface water samples were extracted using solid phase extraction. Soil samples were extracted ultrasonically. Sixteen OCP compounds in the standard solution were detected by a gas chromatography-electron capture detector (GC-ECD). Therefore, the method validation was performed for those 16 OCP compounds. However, 13 OCP compounds could be observed in the samples. The concentrations of most OCPs were higher in samples collected in the summer than those in the autumn. The most frequently observed pesticides were endosulfan sulfate and 4,4'-dichlorodiphenyltrichloroethane (DDT) in groundwater samples, α-HCH in surface water samples, and endosulfan sulfate in soil samples. The average concentration of endosulfan sulfate was the highest in water and soil samples. Compared to the literature values, the average concentrations in this study were lower values. Spatial distribution of OCPs was evaluated with the aid of contour maps for the five districts of Bolu. Generally, agricultural processes affected the water and soil quality in the region. However, non-agricultural areas were also affected by pesticides. The concentrations of pesticides were below the legal limits of European directives for each pesticide.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Agricultura , Mar Negro , Cidades , DDT/análise , Endossulfano/análogos & derivados , Endossulfano/análise , Água Subterrânea/química , Hexaclorocicloexano/análise , Estações do Ano , Solo/química , Turquia
8.
Environ Sci Pollut Res Int ; 22(4): 2515-25, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25339526

RESUMO

The aim of this study was to determine the extent of polycyclic aromatic hydrocarbon (PAH) pollution by measuring PAH levels and 7-ethoxyresorufin-O-deethylase (EROD) activities in flathead mullet (Mugil cephalus) samples caught from the West Black Sea coast of Turkey. The fish samples were caught in August 2008-2011. The levels of 13 PAHs were measured by high-performance liquid chromatography (HPLC) in the liver of fish. Most of the measured PAHs had three rings (low molecular weight). The frequencies of detection of PAHs were higher in fish samples caught from Zonguldak Harbour and Gülüç Stream Mouth than those from Sakarya River Mouth, Amasra and Kefken. EROD activities and cytochrome P4501A (CYP1A) protein level were also measured in the fish liver microsomes. Highly elevated EROD activities and CYP1A levels were measured in the mullet samples caught from Zonguldak Harbour and Gülüç Stream than those from Amasra and Kefken. The detection of PAHs in the liver of fish samples shows recent exposure to PAHs. The chemical analyses of PAHs and EROD activity results together reflected the extent of PAH pollution in the livers of fish caught from the West Black Sea coast of Turkey. The results indicate that Zonguldak Harbour is the most polluted site in the West Black Sea coast of Turkey.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Smegmamorpha/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Mar Negro , Citocromo P-450 CYP1A1/metabolismo , Monitoramento Ambiental/métodos , Feminino , Proteínas de Peixes/metabolismo , Fígado/metabolismo , Masculino , Microssomos Hepáticos/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Turquia , Poluentes Químicos da Água/análise
9.
Environ Monit Assess ; 186(12): 8151-60, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25142504

RESUMO

The objective of this study was to determine the levels of 14 organochlorine pesticides (OCPs) in flathead mullet (Mugil cephalus) caught from the western Black Sea coast of Turkey. The fish samples were caught from five different locations of the western Black Sea coast of Turkey in August 2009. Organochlorine pesticides were extracted from the liver tissues, and then the levels of OCPs were measured using gas chromatography with an electron capture detector. Organochlorine pesticides were detected in all locations. The levels of total OCPs in fish samples ranged between 0.224 and 1.103 µg g(-1) dry weight in the western Black Sea coast of Turkey. DDT, beta-HCH, and endosulfan I were the dominant OCPs in the fish samples. The levels of DDT in fish samples ranged between 0.081 and 0.186 µg g(-1) dry weight. The levels of total HCH in fish samples ranged between 0.007 and 0.376 µg g(-1) dry weight in the western Black Sea coast of Turkey. Although the usage of OCPs was banned in Turkey, the results of this study clearly indicated the presence of OCPs in the western Black Sea coast of Turkey and exposure of living organisms to these chemicals.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Clorados/metabolismo , Praguicidas/metabolismo , Smegmamorpha/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Mar Negro , Cromatografia Gasosa , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Alimentos Marinhos/análise , Alimentos Marinhos/estatística & dados numéricos , Turquia , Poluentes Químicos da Água/análise
10.
J Biochem Mol Toxicol ; 28(6): 271-80, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24756956

RESUMO

The primary objective of this study was to determine specific cytochrome P450 isozyme(s) involved in the metabolism of aldrin to its toxic metabolite dieldrin in flathead mullet (Mugil cephalus) liver microsomes. To identify the cytochrome P450 isozyme responsible for the aldrin metabolism in mullet liver, the effects of mammalian-specific cytochrome P450 inhibitors and substrates were determined in the epoxidation reaction of aldrin. CYP3A-related inhibitors, ketoconazole, SKF-525A, and cimetidine, inhibited the metabolism of aldrin. The contribution of CYP1A to the aldrin metabolism was shown by the inhibition of 7-ethoxyresorufin-O-deethylase activity in the presence of aldrin. The results indicate that CY1A and CYP3A are the cytochrome P450s involved in aldrin epoxidase activity in mullet. In addition, the suitability of aldrin epoxidase activity for monitoring of environmental pollution was also assessed in the fish samples caught from four different locations of the West Black Sea coast of Turkey.


Assuntos
Aldrina/metabolismo , Citocromo P-450 CYP1A1/fisiologia , Citocromo P-450 CYP3A/fisiologia , Proteínas de Peixes/fisiologia , Inseticidas/metabolismo , Smegmamorpha/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Benzoflavonas/farmacologia , Citocromo P-450 CYP1A1/antagonistas & inibidores , Inibidores do Citocromo P-450 CYP3A/farmacologia , Compostos de Epóxi/metabolismo , Inativação Metabólica , Microssomos Hepáticos/enzimologia , Rios
11.
Environ Sci Pollut Res Int ; 21(4): 2907-17, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24154853

RESUMO

A wet-dry deposition sampler was located at The Scientific and Technological Research Council of Turkey-National Metrology Institute (TUBITAK-UME) station, and a bulk deposition sampler was placed at the Kadilli village to determine the atmospheric deposition flux of polycyclic aromatic hydrocarbons (PAHs) and pesticides (organochlorine and organophosphorus) in soluble fraction of samples in Kocaeli, Turkey. The 28 samples for each wet, dry, and total deposition were collected weekly from March 2006 to March 2007. Gas chromatography-tandem mass spectrometry was used to analyze the samples which were prepared by using solid-phase extraction (SPE) method. The sum of volume weighted mean of deposition fluxes was obtained as 7.43 µg m(-2) day(-1) for wet deposition, 0.28 µg m(-2) day(-1) for dry deposition and 0.54 µg m(-2) day(-1) for bulk deposition samples for PAHs and 9.88 µg m(-2) day(-1) for wet deposition, 4.49 µg m(-2) day(-1) for dry deposition, and 3.29 µg m(-2) day(-1) for bulk deposition samples for pesticides. While benzo(a)anthracene had the highest fluxes among PAH compounds for all types of depositions, guthion and phosphamidon had the highest deposition flux compared with the other pesticides. Benzo(ghi)perylene, dibenz(a,h)anthracene, indeno(1,2,3-c,d)pyrene, benzo(a)pyrene, and acenaphthene were not detected in any of the samples. Beta-HCH, gamma-HCH, and endrin aldehyde were the only compounds among 18 organochlorine pesticides to be detected in all deposition samples. The main sources of pesticides were the high number of greenhouses around the sampling stations. However, all of the organophosphorus pesticides were detected in all deposition samples. The pollution sources were identified as coal and natural gas combustion, petrogenic sources, and traffic for TUBITAK-UME station whereas coal and natural gas combustion and traffic were the main sources for Kadilli station by considering the results of factor analysis, ratios, and wind sector analysis.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Agricultura , Poluentes Atmosféricos/química , Carvão Mineral , Monitoramento Ambiental , Análise Fatorial , Hidrocarbonetos Clorados/química , Gás Natural , Praguicidas/química , Hidrocarbonetos Policíclicos Aromáticos/química , Estações do Ano , Solubilidade , Turquia , Emissões de Veículos , Vento
12.
J Chromatogr A ; 1325: 40-8, 2014 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-24369999

RESUMO

Estimation of uncertainty of measurement is a crucial issue to achieve accurate measurement results. When the target has adverse environmental and health effects, accuracy of the results become more important. POPs are the pollutants that have toxic effects and unfortunately, there is a lack of information about uncertainty of the method for determining POPs in air samples. In this work, uncertainty calculations were carried out for PCBs, OCPs, and PAHs in air samples analyzed by using GC-MS and GC-ECD. The main dominant sources for combined uncertainty were calibration curve, recovery and repeatability. The relative uncertainties were found to be in the range of 23-52% for PCBs, 24-59% for OCPs and 23-90% for PAHs.


Assuntos
Poluentes Atmosféricos/análise , Cromatografia Gasosa/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Elétrons , Incerteza
13.
Talanta ; 115: 150-8, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054572

RESUMO

A one-step cleanup method is described for the determination of PAHs, PCBs and OCPs in air (gas and particulate phase) samples. Analytes were extracted from ambient air samples using soxhlet extraction with a solvent mixture of dichloromethane and petroleum ether (1:4) for 24h. They were concentrated, separated and fractionated on a florisil and alumina column. The amounts of florisil (1g or 2g) with/without alumina were tested in the cleanup column. The study systematically investigated the effects of solvent types, and the amounts of florisil and alumina, on the performance of the cleanup process. The first fraction was eluted with 25 mL hexane, and analyzed for PCBs. The second fraction was collected via 40 mL hexane-ethyl acetate (1:1) solvent mixture, and analyzed for OCPs and PAHs. The optimized method yielded average recoveries between 88% and 99% for PCBs; 56% and 118% for PAHs; and 51% and 128% for OCPs. Other validation parameters were also investigated, such as MDL, LOQ, linear range, sensitivity (r(2)). An oven-program optimization and adjustment of GC-MS were performed. For internal quality control, surrogate recoveries and field blanks values were calculated. External calibration curves were prepared for PAHs, and internal calibration curves were preferred for OCP and PCBs.


Assuntos
Poluentes Atmosféricos/isolamento & purificação , Ar/análise , Cromatografia Gasosa-Espectrometria de Massas/normas , Praguicidas/isolamento & purificação , Bifenilos Policlorados/isolamento & purificação , Alcanos , Óxido de Alumínio/química , Calibragem , Silicatos de Magnésio/química , Cloreto de Metileno , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes
14.
J Environ Monit ; 14(5): 1365-74, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22441172

RESUMO

Daily gas and particle phase samples were collected during winter and summer seasons in Bolu, which is located in the high altitude Western Black Sea Region of Turkey. Samples were analyzed to determine the concentrations of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). Concentrations of endosulfan sulfate and methoxychlor were found to be highest in the summer and winter periods, respectively. The measured average concentration of endrin was considerably higher (10-50 fold) than the values reported in the literature for similar sites. The agricultural areas located to the south, south-east and south-west of the sampling point were identified as source regions. PCBs were found predominantly in the gas phase in both seasons and 3-chlorinated biphenyls were found to be abundant in the winter period, due to pollutants transported from the city centre and a waste incineration plant by southerly and easterly winds. The concentrations of PCB-180 and PCB-194 were found to be higher than values reported in the literature. The correlation between atmospheric concentrations and temperature was obtained by using Clausius-Clapeyron (CC) plots. The CC plots for most of the OCPs showed shallow negative slopes with low r(2) values, which might be due to the presence of local sources, i.e., agricultural areas around the sampling site and the dominance of evaporation. The CC plots showed steep positive slopes for most of the PCB compounds. Most of the PCB compounds were carried from the ongoing local sources.


Assuntos
Poluentes Atmosféricos/análise , Hidrocarbonetos Clorados/análise , Material Particulado/análise , Praguicidas/análise , Bifenilos Policlorados/análise , Poluição do Ar/estatística & dados numéricos , Altitude , Atmosfera/química , Mar Negro , Monitoramento Ambiental , Estações do Ano , Turquia
15.
Food Chem ; 132(3): 1555-1561, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29243649

RESUMO

Cadmium, copper, iron, lead, tin and zinc were determined in tomato paste samples by using high resolution inductively coupled plasma mass spectrometry. This study was a part of Proficiency Testing scheme conducted by National Metrology Institute (UME) of Turkey. The method was validated. The percentage relative errors obtained for each element ranged between 1.4% and 9.0% for NIST SRM 1573a, tomato leaves. Measurement uncertainties of all elements were calculated by applying bottom-up approach. The calculated percentage relative uncertainties for the elements were between 8.2% and 16.4%. The major contributions to the uncertainty budget came from the calibration curves, repeatability and recovery. Tomato paste samples gathered from the supermarkets in Turkey were analysed by using the validated method. Their levels were compared both with the literature values and European Commission Regulations.

16.
Talanta ; 79(5): 1298-305, 2009 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-19635363

RESUMO

Simultaneous and multi-elemental method was optimized to determine 35 elements in 274 coarse and fine aerosol samples by using HR-ICP-MS. The procedures were validated. Measurement uncertainties of all elements including sampling uncertainties were calculated by applying bottom-up approach. The average recoveries obtained for each element ranged between 79% and 129% using NIST SRM 1648, urban dust. The calculated uncertainties of the analytical methods were between 2.9% and 18% for both sample types. The major contributions to the uncertainty budget come from the calibration curves, repeatability and volume of air.


Assuntos
Aerossóis/análise , Espectrometria de Massas/normas , Calibragem , Cidades , Poeira/análise
17.
Anal Chim Acta ; 571(2): 298-307, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-17723451

RESUMO

Rapid and practical extraction methods were developed using dichloromethane and ethyl acetate for the routine determination of 16 organochlorine pesticide residues and applied to approximately 30 fresh vegetables (tomato, cucumber and pepper) by using GC-ECD. The procedures were validated. Measurement uncertainties were calculated by applying bottom-up approach. The average recoveries obtained for each pesticide ranged between 65 and 102% at three fortification levels. The uncertainties of the analytical methods were lower than 21 and 16% with and without recovery correction, respectively. The calculated limits of detection and quantification were typically less than 1 ng g(-1) that were much lower than the maximum residue levels.

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