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1.
Sci Total Environ ; 927: 172317, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38588749

RESUMO

This paper presents an evaluation of hexabromocyclododecane (HBCD), polybrominated dibenzo-p-dioxins/furans (PBDD/Fs) and polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) outflows during the destruction of HBCD waste stockpiles in IZAYDAS Hazardous Waste Incinerator (HWI) in Kocaeli, Türkiye. HBCD wastes containing 100 % pure HBCD were in 25 kg packages with 63 % Br content were co-incinerated in a 3-day test burn with average feed rate of 26 kg/h. HBCD, PBDD/Fs and PCDD/Fs were measured in the outlet streams to quantify the amount of unintended POPs releases associated with the processing of HBCD waste and to observe the POP removal performance of air pollution control equipment (APCE) of the incinerator. Total mass outflow rate of HBCDs is calculated as 2.6 g/day, corresponding to destruction efficiency of 99.9996 %. Total toxicity of the brominated dioxins was measured as 0.00044 ng TEQ/Nm3 on average, while highly brominated congeners are dominant. PCDD/F concentrations in the outflow streams during HBCD test burns are produced similar congener distributions with those given in the previous studies, with the dominance of 7,8-chlorinated congeners. Mass flows in the outlet streams indicated that the efficiency of ESP and wet scrubbers for the removal of PCDD/Fs and HBCDs. Flue gas concentrations of PCDD/Fs, HBCDs and PBDD/Fs obtained in HBCD burn test indicated that burning HBCD wastes cause no significant emissions as operational parameters and total halogen content in the menu are kept within the incinerator limits.

2.
Mar Pollut Bull ; 202: 116339, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38598932

RESUMO

The main objectives of this study are to measure permanent organic and inorganic pollutants in detail in an area that hosts historical structures underneath and feeds the huge ecosystem with water, to reveal risk values. Total PAH concentrations in the samples ranged from 43.41 to 202.7 ng/g. Total OCP concentration ranged from 5.15 to 17.98 ng/g, while total PCB concentration ranged from 0.179 to 0.921 ng/g. PCB 28/31, 138, and 153 are the highest detected PCBs. It was found that the lake sediment reached toxic equivalent quotient (TEQ) values of 29.21 for total PAHs and 28.90 for carcinogenic PAHs. Negligible concentration risk quotient had a low to moderate ecological and toxicological risk between 12.91 and 64.42. Highest pollution index value was found 3.81 and the risk index value reached 417.4. It has been revealed that toxicologically risky components accumulate over many years even in the best-protected water resources.

3.
Plants (Basel) ; 12(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36987079

RESUMO

The aim of this work was to investigate the microwave-assisted extraction (MAE) kinetics of polyphenolic compounds from organic peppermint leaves. The phytochemicals of peppermint (Mentha piperita L.) are increasingly used in food technology due to their numerous biological activities. The processing of various plant materials by MAE and the production of high-quality extracts is becoming increasingly important. Therefore, the influence of microwave irradiation power (90, 180, 360, 600, and 800 W) on total extraction yield (Y), total polyphenols yield (TP), and flavonoid yield (TF) were investigated. Common empirical models (first-order, Peleg's hyperbolic, Elovich's logarithmic, and power-law model) were applied to the extraction process. The first-order kinetics model provided the best agreement with the experimental results in terms of statistical parameters (SSer, R2, and AARD). Therefore, the influences of irradiation power on the adjustable model parameters (k and Ceq) were investigated. It was found that irradiation power exerted a significant influence on k, while its influence on the asymptotic value of the response was negligible. The highest experimentally determined k (2.28 min-1) was obtained at an irradiation power of 600 W, while the optimal irradiation power determined by the maximum fitting curve determination predicted the highest k (2.36 min-1) at 665 W.

4.
J Food Sci Technol ; 60(1): 73-83, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36618055

RESUMO

In this study, antioxidant (DPPH and metal chelating), DNA cleavage, biofilm, and antimicrobial properties of extracted phenol from the walnut green husk (WGH) and its different concentrate and permeate samples were evaluated. For maximum phenolic compound extraction from the WGH first, the effects of solvent type (deionized water, methanol, n-hexane, acetone, and ethanol), solvent temperature (25-75 °C), and extraction time (0.5-24 h) were optimized. Then to concentrate phenolic compounds a pressure-driven membrane process was used with four different membrane types. The phenol contents of the concentrate samples were found to be microfiltration (MF) concentrate 4400 mg/L, ultrafiltration (UF) concentrate 4175 mg/L, nanofiltration (NF) concentrate 8155 mg/L, and reverse osmosis (RO) concentrate 8100 mg/L. LC-MSMS was used to determine the quantification of phenolic compounds in permeate and concentrate streams. In addition, all of the concentrate samples with high phenol content showed a high antioxidant activity as 100% with MF concentrate, UF concentrate, NF concentrated and RO concentrated. Likewise, concentrate samples were found to have very high antibiofilm activity as 82.86% for NF concentrate againts S. aureus, 85.80% for NF concentrate against P. aureginosa, 80.95% for RO concentrate against S. aureus, and 83.61% for RO-concentrate against P. aureginosa. When the antimicrobial activity of the extracted phenol from WGH and its different concentrate and permeate samples were evaluated by micro dilution and disk diffusion methods, it was found that the ability of the concentrate samples to inhibit bacterial growth was much higher than permeate ones. In addition, extracted phenol from WGH and its different concentrate and permeate samples showed significant DNA nuclease activity. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-022-05588-w.

5.
Environ Geochem Health ; 45(6): 3985-4006, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36631577

RESUMO

This study presents the distribution of persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) in the sediments from four dams and two ponds in the Çanakkale city, Türkiye. The total concentration varied from 41.47 to 145.45 ng/g d.w. for PAHs; 1.40-14.96 ng/g d.w. for organochlorine pesticides (OCPs) and 0.13-3.31 ng/g d.w. for polychlorinated biphenyls (PCBs). The total polychlorinated dibenzo-p-dioxins/furans (∑PCDD/Fs) concentrations varied between 7.35 and 63.46 pg/g d.w. The HM distribution in sediments ranged from 9.41 to 21.13 mg/kg d.w. for As; 0.20-0.39 mg/kg d.w. for Cd; 19.4-281.68 mg/kg d.w. for Cr; 23.50-118.25 mg/kg d.w. for Pb and 118.9-374.82 mg/kg d.w. for Zn. This paper also elucidates possible sources of POP and HMs in sediment by using diagnostic ratios. The calculated ratios were shown that anthropogenic input is the source of these pollutants in sediments. Principal component analysis showed that the low molecular weight of POPs is considerably related and correlated, while high molecular weight pollutants have made another group and highly correlated with each other. The results indicated that anthropogenic pollution is mainly related to atmospheric input. Anthropogenic pollutants are more apparent at Atikhisar and Bakacak dams close to urbanized locations. Rather than the anthropogenic impact, based on the measured data interpretation, the global climate change effect was seen in Bakacak dam. The overall concentration of all pollutants revealed that Atikhisar and Bakacak sediments are high-level polluted areas according to several types of sediment guidelines.


Assuntos
Poluentes Ambientais , Metais Pesados , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Poluentes Orgânicos Persistentes , Lagos/análise , Poluentes Químicos da Água/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental/métodos , Metais Pesados/análise , Bifenilos Policlorados/análise , Poluentes Ambientais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
6.
Environ Sci Pollut Res Int ; 29(60): 90923-90935, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35881293

RESUMO

The current situation of the water resources of Istanbul, which is one of the important metropolises of Europe, should be known and constantly monitored by the reasons of the rapid increase in the city population, the acceleration of production-related industrial activities, the expansion of the city with construction activities, and the decrease in precipitation. The purpose of this study was to reveal the situations of surface sediments collected from Istanbul water reservoirs in terms of PCDD/Fs and DL-PCBs, to identify possible sources, and to conduct their ecological risk assessment. Total PCDD/Fs and DL-PCBs concentrations varied between 28.13 and 457.4 pg/g (average 136.8 pg/g) and 12.19-340.1 pg/g (average 72.09 pg/g). The corresponding TEQ values of PCDD/Fs and DL-PCBs were between 0.53 and 5.37 pg TEQ/g (average 2.23 pg TEQ/g) and 0.02-0.44 pg TEQ/g (average 0.12 pg TEQ/g), respectively. Octachlorodibenzo-p-dioxin (OCDD) is the dominant congener by constituting about 75% of the total PCDD/Fs on average, while congener distributions of DL-PCBs showed the dominance of PCB-118 and PCB-105. The sediments taken from Kazandere dam have the lowest pollution levels for both PCDD/Fs and DL-PCBs. The highest PCDD/F and DL-PCB amounts were measured in sediments of Alibey and Elmali dams (closest to highly populated settlements of Istanbul), which are most affected by the air pollution caused by the traffic, commercial/industrial combustion (like waste incineration facility) and combustion for residential heating. Almost all the sediments have total dioxin-like toxicity levels higher than the safe threshold level (with two exceptions) of 0.85 pg TEQ/g dw, proposed for ecological risk. Health risk assessment shows that levels of dioxin-like compounds would result in a total intake of 0.33 pg TEQ/kg bw/day even in the worst-case scenario, not exceeding the tolerable daily intake value of 1 pg TEQ/kg bw/day. Among exposure pathways, consumption of fish constitutes almost all the total intake, while contributions of other pathways are minimal.


Assuntos
Dioxinas , Dibenzodioxinas Policloradas , Dibenzofuranos , Europa (Continente) , Medição de Risco
7.
Mar Pollut Bull ; 175: 113172, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34844748

RESUMO

Istanbul needs to be protected and constantly monitored water resources due to its increasing population and the decrease in precipitation. This study aims to comprehensively reveal surface sediments collected from reservoirs that supply water to Istanbul concerning POPs (PAHs, PCBs, and OCPs) and heavy metals; to identify possible sources of PAHs, and conduct their ecological risk assessment. Pollution indices in this study were used as contamination degree (CD) contamination factor (CF), geoaccumulation index (Igeo), pollution load index (PLI) and Sediment Quality Guidelines (SQGs). Total PAH concentrations of surface sediments at the sampling points ranged from 46.29 ng/g (A7) to 403.9 ng/g (A15). Benzo(b)fluoranthene (5.647-59.42 ng/g), Pyrene (3.625-83.10 ng/g), Fluoranthene (3.363-66.48 ng/g), Phenanthrene (3.115-52.48 ng/g), Chrysene (3.532-43.98 ng/g), Naphthalene (6.606-36.20 ng/g), Benzo(g,h,i)perylene (3.316-41.73 ng/g) and Indeno(1,2,3-c,d)pyrene (3.453-38.84 ng/g) are the dominant PAH compounds. PAH pollution may be caused by the village-town settlements near the dam and the O7-D020 highway. Total OCP concentration ranged from 2.233 ng/g (A12) to 7.337 ng/g (A1), while total PCB concentration ranged from 0.246 ng/g (A13) to 3.708 ng/g (A1). The lowest total OCP and PCB concentrations were found in surface sediments taken from Kazandere, Papuçdere and Alibey Dam lakes. DDT p,p (0.072-5.177 ng/g) has the highest concentration among all sediment samples. While the most dominant OCP compounds in the samples were DDT p,p, DDE p,p and DDD p,p, HCH alpha, HCH beta, respectively, PCB 153, 138 and 180 were the highest detected PCB congeners in the same samples. Total heavy metal concentration varied from 77,812 mg/kg to 267,072 mg/kg. According to PAH diagnostic analysis, the surface sediments of Terkos, Büyükçekmece, Elmali, Darlik, Sazlidere, Alibey and Ömerli Dams were polluted by petrogenic sources, while the surface sediments of Kazandere and Papuçdere Dams were affected by pyrogenic sources. None of the levels of POPs in the samples exceeded the ERM values. Slight and moderate contamination of heavy metals, such as Pb and Zn, were present in most of the sampling points according to CD, CF, PLI and Igeo values. The quality criteria of heavy metals showed that almost all of the sampling points had Cd, Pb and Hg concentrations below the ERL values. The Ni concentrations at most of the sampling points significantly exceeded the ERM values. The concentrations of As, Cr, Cu and especially Ni and Zn exhibit a significant toxic risk to aquatic organisms to sediment quality criteria.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Lagos , Metais Pesados/análise , Medição de Risco , Turquia , Poluentes Químicos da Água/análise
8.
Mar Pollut Bull ; 172: 112884, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34454391

RESUMO

Surface sediments from the Yesilirmak River and the near coastal area in the Black Sea were collected using sediment traps to assess the spatial distributions of persistent organic pollutants and find their potential sources. Analyses were carried out to determine the concentrations of the persistent organic pollutants of seventeen polychlorinated dibenzo-p-dioxins and dibenzofurans, sixteen polycyclic aromatic hydrocarbons, seven polychlorinated biphenyls, and eight organochlorine pesticides using high-resolution gas chromatography-mass spectrometry and gas chromatography-tandem mass spectrometry systems. Analysis showed that the three main components of persistent organic pollutants (polychlorinated dibenzo-p-dioxins and dibenzofurans, polycyclic aromatic hydrocarbons, and organochlorine pesticides) primary sources are industrial activities. In addition, the widespread occurrence of persistent organic pollutants in the watershed surface sediments taken from the Yesilirmak River basin showed that agricultural and urban areas are also diffuse persistent organic pollutants sources.


Assuntos
Bifenilos Policlorados , Poluentes Químicos da Água , Mar Negro , Dibenzofuranos Policlorados , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Sedimentos Geológicos , Poluentes Orgânicos Persistentes , Bifenilos Policlorados/análise , Rios , Poluentes Químicos da Água/análise
9.
Environ Sci Pollut Res Int ; 28(19): 24830-24846, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33651287

RESUMO

The European Water Framework Directive (WFD) (2000/60/EC) is the most visionary piece of European environmental legislation that aims to achieve good water status of both surface water and groundwater bodies. The Directive provides a fundamental basis for surface water monitoring activities in the European Member States. The objective of this study is to investigate the occurrence of micropollutants in the Yesilirmak River and to develop a cost-effective monitoring strategy based on spatiotemporal data. A 2-year seasonal monitoring program was conducted between 2016 and 2018, and the water samples were analyzed for 45 priority substances as defined by the WFD and 250 national river basin-specific pollutants. In the basin, 166 pollutants were quantified in at least one of the samples with individual concentrations ranging from 6 × 10-6µg/L to 100 mg/L. Fifty-four pollutants with a frequency of occurrence greater than 5% were selected for further evaluation. Based on statistical evaluation of the data, 20 pollutants were identified as the pollutants of primary concern. These 20 pollutants were grouped under three categories (metals, biocides, and industrial organic compounds) and their spatiotemporal distributions in the basin were assessed to establish a monitoring strategy specific to each pollutant category. The results of the study revealed that the common season for the monitoring of all pollutant categories was the spring. This study provides a generic methodology for the development of a cost-effective water quality monitoring strategy, which can be applicable for use in different basins and pollutant datasets.


Assuntos
Rios , Poluentes Químicos da Água , Monitoramento Ambiental , Turquia , Poluentes Químicos da Água/análise , Qualidade da Água
10.
J Mass Spectrom ; 55(12): e4672, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33215819

RESUMO

Nowadays, a wide variety of chemicals has emerged because of increasing industrial and human activities. Thus, environmental chemistry laboratories performing analytical measurements need rapid and sensitive methods more than ever to get reliable quantitative data. For this purpose, a purge and trap gas chromatography-mass spectrometry (GC-MS) method was developed and validated for the rapid, simple, and sensitive determination of the presence of naphthalene and its derivatives in waters. The method validation was based on specificity, calibration curve linearity, limit of detection (LOD) and limit of quantification (LOQ), accuracy (recovery), precision, matrix effects (MEs), and measurement uncertainty. This method showed excellent linearity from 1.00 to 40.00 µg/L except naphthalene (0.50-40.00 µg/L) because the correlation coefficients were higher than 0.997 for all analytes. The LOQ values varied from 0.312 to 0.746 µg/L, and the LOD values changed from 0.094 to 0.224 µg/L with relative standard deviations (RSDs) for all compounds below 10% (3.12-7.46), respectively. Recoveries ranged from 81.9% to 95.6%, and repeatability and reproducibility (in terms of RSD for six measurements) were lower than 10% in all cases. F test was subjected on the related data at 95% confidence level, and no statistically significant difference was observed. There was no critical ME (recovery varied from 80% to 110% in all matrices). In measurement uncertainty, the expanded uncertainties of each analyte were changed in the range of 0.39-0.52 µg/L, and the calibration curve and repeatability had dominant effects on the combined uncertainty. The application to real samples was successfully assessed by the developed method. These results indicate that the developed method is suitable for the determination of naphthalene and its derivatives in waters.

11.
J Fungi (Basel) ; 6(4)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105686

RESUMO

Food processing industry by-products (apple, pomegranate, black carrot, and red beet pulps) were evaluated as raw materials in pigment production by the filamentous fungi Aspergillus carbonarius. The effect of fermentation conditions (solid and submerged-state), incubation period (3, 6, 9, 12, and 15 d), initial substrate pH (4.5, 5.5, 6.5, 7.5, and 8.5), and pulp particle size (<1.4, 1.4-2.0, 2-4, and >4 mm) on fungal pigment production were tested to optimize the conditions. Pigment extraction analysis carried out under solid-state fermentation conditions showed that the maximum pigment production was determined as 9.21 ± 0.59 absorbance unit at the corresponding wavelength per gram (AU/g) dry fermented mass (dfm) for pomegranate pulp (PP) by A. carbonarius for 5 d. Moreover, the highest pigment production was obtained as 61.84 ± 2.16 AU/g dfm as yellowish brown at initial pH 6.5 with < 1.4 mm of substrate particle size for 15-d incubation period. GC×GC-TOFMS results indicate that melanin could be one of the main products as a pigment. SEM images showed that melanin could localize on the conidia of A. carbonarius.

12.
Anal Bioanal Chem ; 412(21): 5169-5178, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32173792

RESUMO

The aim of this work is the highly sensitive determination of 117 contaminants in surface waters at very low concentrations. Gas chromatography-amenable priority compounds from the European Water Framework Directive (EWFD, 45 priority substances) and substances from the Turkish Regulation on the Management of Surface Water Quality (TRMSWQ, 250 substances) were analyzed. Almost a third to one half of the compounds in the TRMSWQ list were successfully detected in a single gas chromatography-tandem mass spectrometry (GC-MS/MS) injection. Analyzing these pollutants in water samples is difficult with conventional extraction methods. An efficient, easy and fast method for both extraction and analysis is thus important. Here, the stir bar sorptive extraction (SBSE) approach employing Twister® was used for analyte enrichment from 100 mL water samples. The Twister apparatus was used for thermal desorption. Compounds were separated via gas chromatography (GC) and detected by tandem mass spectrometry (MS/MS) utilizing an Agilent 7000D MS instrument. The analysis method was comprehensively validated, and complied with the requirements of the EWFD and Turkish regulation for surface water quality for inland surface water. The method includes various endocrine disruptor compounds listed in the EWFD, such as polychlorinated biphenyls, polycyclic aromatics hydrocarbons, polybrominated diphenyl ethers, phenols, phthalates and pesticides. The method is also applicable for the analysis of similar contaminants that are not on this list. The analyzed pollutants have varying polarities based on octanol-water coefficients and are extracted by SBSE. This method may be preferred for the analysis of pollutants with an octanol-water partition coefficient (log Ko/w) higher than 2. The SBSE method, which is easy, lab-friendly and quick, taking a total of only 2 h for parameter analysis, was optimized to reduce time and chemical usage. The entire extraction and analysis was completed in virtually 3 h. The limits of quantification (LOQs) ranged from 0.12 to 50 ng/L and complied with the requirements for analytical methods to be used in the analysis of the compounds included in the directives. Several quality parameters including linearity, trueness and precision were studied, with good results, and uncertainty was also estimated. Precision (in terms of relative standard deviation [RSD]) was lower than 40%, recoveries ranged from 60 to 120%, and determination coefficients were higher than 0.990 for all analytes. Graphical abstract.


Assuntos
Disruptores Endócrinos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Calibragem , Europa (Continente) , Água Doce/química , Limite de Detecção , Reprodutibilidade dos Testes
13.
Environ Sci Pollut Res Int ; 27(12): 13902-13914, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32036522

RESUMO

The study includes the determination of the general background PCDD/F and dl-PCB levels in environmental (ambient air and soil) and food (meat, milk, egg, leafy vegetable, root vegetable and fruit samples) samples collected in four sampling sites in the vicinity of IZAYDAS WIP and its possible health risks. The local and meteorological conditions (prevailing wind direction, season, raining, and soil structure) were taken into account in the selection of sampling sites. The concentrations of PCDD/F and dl-PCB in ambient air ranged from 0.00841 to 0.05881 pg I-TEQ/m3. These results are quite low and it showed that there is no significant PCDD/F pollution in the vicinity of the plant. The results of PCDD/F and dl-PCB in eight soil samples (four in the range of 0-1.2 km, four in the range of 1.2-5 km) taken from the vicinity of IZAYDAS varied between 0.12681 and 0.4353 pg TEQ/g. The levels of PCDD/F and dl-PCBs measured in food samples were found to be significantly lower than both the limit values given by the Turkish Food Codex and the levels measured in the previous studies (between 2008 and 2009). In the health risk assessment, carcinogenic risk was calculated for PCDD/F and dl-PCBs made according to the exposure scenarios established for the study. The total intake values for the sum of PCDD/F and dl-PCB were found between 0.08 and 0.37 pg TEQ/kg.day for adults. These values are well below the limit value, which is considered as 2 pg WHO-TEQ/kg body weight.day. In this context, it was concluded that carcinogenic risk due to PCDD/F and dl-PCB intake is significantly low in the vicinity of the plant.


Assuntos
Benzofuranos , Dioxinas , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas , Dibenzofuranos Policlorados , Turquia
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