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1.
Pan Afr Med J ; 40: 45, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34795826

RESUMO

INTRODUCTION: neffa, a form of air-dried smokeless tobacco used in North Africa, is spuriously perceived as a lower risk alternative to smoking. The objective of this study was to provide information on some harmful constituents of neffa and to use them for cancer risk assessment. METHODS: a high-performance liquid chromatography method coupled with fluorescence detector was used to determine polycyclic aromatic hydrocarbons (PAHs) in one sample of neffa. An atomic absorption spectrometry was performed to determine the concentrations of lead and cadmium in three samples of neffa. The levels of toxicants found in neffa were used to assess for lifetime cancer risk as advocated by the US Environment Protection Agency. RESULTS: the determination of PAHs in neffa allowed the identification of phenanthrene and anthracene. However, the higher molecular weight PAHs such as Benzo(a)Pyrene B(a)P were not detected. The concentrations of cadmium and lead varied between 1.3 to 2.8µg/g and 1.7 to 4.6µg/g respectively. Cancer risk for cadmium and lead varied between 4.2E-03 to 9.3E-03 and 2.5E-06 to 6.4E-06 respectively. Cancer risk for Cd exceeded the range of 10E-04 to 10E-06 of an acceptable risk. CONCLUSION: neffa is not a healthy alternative for overcoming smoking addiction. It contains mineral and organic pulmonary toxicants. This study could serve as a scientific basis to inform consumers about the products´ toxicity and help them to quit smokeless tobacco (SLT) use.


Assuntos
Neoplasias/etiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Tabaco sem Fumaça/análise , Cádmio/análise , Carcinógenos/análise , Carcinógenos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Humanos , Chumbo/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Medição de Risco , Espectrofotometria Atômica , Uso de Tabaco/efeitos adversos , Tabaco sem Fumaça/efeitos adversos , Tunísia
2.
Chemosphere ; 244: 125523, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31812054

RESUMO

Schwertmannite, jarosite or goethite are commonly used to remove metals and/or metalloids from contaminated water via adsorption processes, but it is still unclear whether they can be used as adsorbents to remove hydrophobic organic pollutants (HOCs), such as polycyclic aromatic hydrocarbons (PAHs), from groundwater or wastewater. Here, the feasibility of using these iron (oxyhydr) oxide minerals as adsorbents for phenanthrene (a model PAH) adsorption and regenerating the spent adsorbents via heterogeneous Fenton-like reaction was investigated. Results showed that they exhibited rapid adsorption rates and considerable adsorption capacities for phenanthrene. The maximum Langmuir capacities (Qmax) for phenanthrene adsorption at 28 °C were in an ascending order of goethite (567 µg·g-1) < schwertmannite (727 µg·g-1) < jarosite (2088 µg·g-1). The adsorption process was a spontaneous and exothermic process along with the decrease of randomness at the solid/liquid interfaces, which was influenced by temperature, adsorbent dosage, and the coexistence of inorganic anions. Both schwertmannite and jarosite were superior to goethite in light of their easy separation from the bulk solution after the adsorption processes. A multi-cycle experiment demonstrated that the regeneration efficiency of schwertmannite (97.9-99.7%) was much higher than that of jarosite (80.1-87.2%), and the mineral structure, morphology and functional groups of schwertmannite were not changed during the successive adsorption-regeneration processes. Therefore, among the investigated three iron (oxyhydr) oxide minerals, schwertmannite was an attractive and regenerable adsorbent for the removal of phenanthrene from water owing to its high adsorption capacity, good separation ability, and excellent reusability.


Assuntos
Adsorção , Compostos de Ferro/química , Fenantrenos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Compostos Férricos/química , Peróxido de Hidrogênio/química , Minerais/química , Compostos Orgânicos/isolamento & purificação , Sulfatos/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos
3.
Chemosphere ; 229: 227-235, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31078879

RESUMO

Endpoint assessment using biological systems in combination with the chemical analysis is important for evaluating the residual effect of contaminants following remediation. In this study, the level of residual toxicity of polycyclic aromatic hydrocarbons (PAHs) after 120 days of phytoremediation with five different plant species:- maize (Zea mays), Sudan grass (Sorghum sudanense), vetiver (Vetiveria zizanioides), sunflower (Helianthus annuus) and wallaby grass (Austrodanthonia sp.) has been evaluated by ecotoxicological tests such as root nodulation and leghaemoglobin assay using garden pea (Pisum sativum) and acute, chronic and genotoxicity assays using earthworm (Eisenia fetida). The phytoremediated soil exhibited lesser toxicity supporting improved root nodulation and leghaemoglobin content in P. sativum and reducing DNA damage in E. fetida when compared to contaminated soil before remediation. Also, the results of the ecotoxicological assays with the legume and earthworm performed in this study complemented the results obtained by the chemical analysis of PAHs in phytoremediated soil. Therefore, these findings provide a basis for a framework in which remediation efficacy of PAHs-contaminated sites can be evaluated effectively with simple ecotoxicological bioassays using legumes and earthworms.


Assuntos
Oligoquetos/metabolismo , Pisum sativum/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/isolamento & purificação , Poluentes do Solo/metabolismo , Animais , Biodegradação Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Poluentes do Solo/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-30104500

RESUMO

Co-contaminated soils containing heavy metals and polycyclic aromatic hydrocarbons (PAHs) are an environmental and human health risk. Research into the remediation of these soils is imperative. In this paper, a novel investigation utilizing calcination technique to stabilize heavy metals and simultaneously remove PAHs in soil was conducted. Calcination temperature (300⁻700 °C) was observed to play a dominant role in heavy metal stabilization and PAH removal in soils. However, calcination time (0.5⁻8 h) had no significant effect on these contaminants during calcination at different temperatures. Considering the remediation cycle requirements and economic costs of engineering, we suggested that the optimal calcination condition for Zn, Cu, naphthalene, and fluoranthene was at 700 °C for 0.5 h, and the corresponding stabilization or removal efficiency values were 96.95%, 98.41%, 98.49%, and 98.04%, respectively. Results indicate that calcination as a remedial strategy exhibits a bright future for practical applications in the simultaneous stabilization of heavy metals and PAH removal from co-contaminated sites.


Assuntos
Recuperação e Remediação Ambiental/métodos , Temperatura Alta , Metais Pesados/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Custos e Análise de Custo , Recuperação e Remediação Ambiental/economia , Solo/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-29764288

RESUMO

Sixteen polycyclic aromatic hydrocarbons (PAHs) and some typical substituted polycyclic aromatic hydrocarbons (SPAHs) were investigated in wastewater treatment plants (WWTPs) and effluent effluent-receiving rivers in order to indentify the elimination of these compounds in WWTPs, as well as the potantial potential risk in the effluent-receiving rivers. The concentrations of ΣPAHs in the total phase (combined dissolved and adsorbed phases) in influent were between 944.1 and 1246.5 ng·L-1, and ΣSPAHs, including methyl PAHs (MPAHs) and oxygenated PAHs (OPAHs), between 684.9 and 844.9 ng·L-1. Regarding the SPAHs, the concentrations of ΣOPAHs (312.3 ng·L-1) were higher than those of ΣMPAHs (271.8 ng·L-1). The total removal efficiencies of PAHs in the biological treatment processes were between 59% and 68%, and those of SPAHs were a little lower (58-65%). The removal efficiency in the adsorbed phase was higher than in the dissolved phase. The concentrations of PAHs and SPAHs in the effluent were a little higher than in the receiving river. According to a PAH risk assessment of the effluent, 7 carcinogenic PAHs accounted for a relatively high proportion. Benzo[a]pyrene (BaP) and Dibenz[a,h]anthracene (DBA) were major contributors to the TEQs in the effluent of WWTPs, which should be taken into consideration.


Assuntos
Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Pequim , China , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Medição de Risco , Eliminação de Resíduos Líquidos/normas
6.
Food Chem ; 257: 44-52, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622229

RESUMO

A sensitive GC-MS method is reported for the determination of twelve polycyclic aromatic hydrocarbons (PAHs) in baby food. The sample preparation involves QuEChERS extraction combined with low-density solvent dispersive liquid-liquid microextraction (LDS-DLLME) and ultra-low temperature (-80 °C). Plackett-Burman screening design was employed to identify the main sample preparation variables that affect the extraction efficiency, such as the volume of toluene used in LDS-DLLME. The suitability of proposed method was verified by analytical selectivity, linearity in solvent and matrix-matched calibration curves and adequate recoveries (72-112%) and precision (RSD values ≤11%), under repeatability and within-laboratory reproducibility conditions. High analytical sensitivity was achieved for the monitoring of PAHs at the strict limit of 1 µg kg-1 fixed by the European Commission for baby foods. The validated method was applied to thirty-two commercial baby food samples, and the investigated PAHs were not detected in any sample.


Assuntos
Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Alimentos Infantis/análise , Microextração em Fase Líquida/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Solventes/química , Métodos Analíticos de Preparação de Amostras , Análise de Alimentos/economia , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/economia , Hidrocarbonetos Policíclicos Aromáticos/química , Reprodutibilidade dos Testes
7.
Anal Bioanal Chem ; 410(13): 3059-3071, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29607448

RESUMO

Currently there is a lack of inexpensive, easy-to-use technology to evaluate human exposure to environmental chemicals, including polycyclic aromatic hydrocarbons (PAHs). This is the first study in which silicone wristbands were deployed alongside two traditional personal PAH exposure assessment methods: active air monitoring with samplers (i.e., polyurethane foam (PUF) and filter) housed in backpacks, and biological sampling with urine. We demonstrate that wristbands worn for 48 h in a non-occupational setting recover semivolatile PAHs, and we compare levels of PAHs in wristbands to PAHs in PUFs-filters and to hydroxy-PAH (OH-PAH) biomarkers in urine. We deployed all samplers simultaneously for 48 h on 22 pregnant women in an established urban birth cohort. Each woman provided one spot urine sample at the end of the 48-h period. Wristbands recovered PAHs with similar detection frequencies to PUFs-filters. Of the 62 PAHs tested for in the 22 wristbands, 51 PAHs were detected in at least one wristband. In this cohort of pregnant women, we found more significant correlations between OH-PAHs and PAHs in wristbands than between OH-PAHs and PAHs in PUFs-filters. Only two comparisons between PAHs in PUFs-filters and OH-PAHs correlated significantly (rs = 0.53 and p = 0.01; rs = 0.44 and p = 0.04), whereas six comparisons between PAHs in wristbands and OH-PAHs correlated significantly (rs = 0.44 to 0.76 and p = 0.04 to <0.0001). These results support the utility of wristbands as a biologically relevant exposure assessment tool which can be easily integrated into environmental health studies. Graphical abstract PAHs detected in samples collected from urban pregnant women.


Assuntos
Poluentes Ocupacionais do Ar/análise , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Silicones/química , Poluentes Ocupacionais do Ar/isolamento & purificação , Poluentes Ocupacionais do Ar/urina , Biomarcadores/análise , Biomarcadores/urina , Estudos de Coortes , Monitoramento Ambiental/instrumentação , Feminino , Humanos , Limite de Detecção , Exposição Materna , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/urina , Gravidez
8.
Food Addit Contam Part B Surveill ; 11(2): 138-145, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29486658

RESUMO

A total of 77 traditionally smoked meat samples produced in Latvia, Lithuania, and Estonia were tested for the occurrence of four EU regulated polycyclic aromatic hydrocarbons (PAHs). Levels of PAHs exceeding the EU maximum levels for benzo[a]pyrene and for the sum of four PAHs (PAH4) were detected in 46% and 48% of the samples originating from Latvia. The detected BaP levels in smoked meats ranged from 0.05 to 166 µg kg-1, while the PAH4 content ranged from 0.42 to 628 µg kg-1. The mean dietary exposure to PAHs was estimated at the levels of 5.4 ng BaP/kg bw/day and 36 ng PAH4/kg bw/day. The margin of exposure (MOE) approach was utilised to assess the risks to Latvian consumers due to PAHs and the obtained MOEs were in a range of 7205-24,434, thus indicating a potential concern for consumer health for specific population groups.


Assuntos
Carcinógenos Ambientais/análise , Dieta/efeitos adversos , Contaminação de Alimentos , Alimentos em Conserva/análise , Produtos da Carne/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Métodos Analíticos de Preparação de Amostras , Países Bálticos , Calibragem , Carcinógenos Ambientais/isolamento & purificação , Carcinógenos Ambientais/toxicidade , Cromatografia Gasosa , Dieta/etnologia , União Europeia , Inspeção de Alimentos , Preferências Alimentares/etnologia , Conservação de Alimentos , Alimentos em Conserva/efeitos adversos , Alimentos em Conserva/economia , Alimentos em Conserva/normas , Humanos , Limite de Detecção , Produtos da Carne/efeitos adversos , Produtos da Carne/economia , Produtos da Carne/normas , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Reprodutibilidade dos Testes , Medição de Risco , Fumaça , Propriedades de Superfície , Espectrometria de Massas em Tandem
9.
Food Addit Contam Part B Surveill ; 11(2): 146-152, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29486662

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are food-processing contaminants considered to be carcinogenic and genotoxic. Due to its drying process stage, teas may be contaminated with PAHs. The aim of the study was to validate an analytical method involving QuEChERS and HPLC-FLD for the determination of PAH4 in teas and evaluate the contamination levels in 10 different types of teas from Brazil. Recoveries varied from 54% to 99% and relative standard deviations from 1% to 21%. Limits of detection and quantification were from 0.03 to 0.3 µg/kg and 0.1 to 0.5 µg/kg, respectively. Mate tea presented the highest PAH levels, with PAH4 varying from 194 to 1795 µg/kg; followed by black (1.8-186 µg/kg), white (24-119 µg/kg), and green teas (3.1-92 µg/kg). Teas with lowest PAH4 were strawberry, lemongrass, peppermint, and boldo. Only trace levels of PAHs were detected in tea infusions, so apparently it would not affect PAH intake by Brazilian population.


Assuntos
Carcinógenos Ambientais/análise , Contaminação de Alimentos , Hidrocarbonetos Policíclicos Aromáticos/análise , Chá/química , Chás de Ervas/análise , Métodos Analíticos de Preparação de Amostras , Benzo(a)Antracenos/análise , Benzo(a)Antracenos/isolamento & purificação , Benzo(a)pireno/análise , Benzo(a)pireno/isolamento & purificação , Brasil , Carcinógenos Ambientais/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Crisenos/análise , Crisenos/isolamento & purificação , Fluorenos/análise , Fluorenos/isolamento & purificação , Manipulação de Alimentos , Inspeção de Alimentos/métodos , Ilex paraguariensis/química , Limite de Detecção , Oxirredução , Folhas de Planta/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Reprodutibilidade dos Testes , Espectrometria de Fluorescência , Chá/economia , Chás de Ervas/economia
10.
Recent Pat Biotechnol ; 12(1): 3-20, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28474558

RESUMO

BACKGROUND: In today's world one of the major environmental problems is the contamination of aquatic or terrestrial ecosystem due to spillage of hydrocarbon compounds produced due to various activities related to the petrochemical industry. In recent years, bioremediation has emerged as a promising technology for the restoration of these contaminated sites in an ecofriendly way. OBJECTIVE: The aim of present review literature is the compilation of patent documents on bioremediation of petroleum hydrocarbon pollutants to know technological advancements in this field. METHODS: This analysis was based on various criteria i.e. patenting trend over time, country-wise and assignee-wise comparisons and types of technology used in various patents. Some publicly available patent databases were used to retrieve the patent information from the year 2000 to 2016. RESULTS: Patent applications were retrieved and it was observed that different types of technological approaches were used in developing the patents. United States accounted for maximum patent publications, followed by China, Korea, Japan, Russia, Great Britain, Mexico, India and Canada in developing bioremediation technologies. US based organization DU PONT is the leading group as patent assignee followed by Biosaint Co. Ltd in Korea. CONCLUSION: Patenting activity in the field of bioremediation of petroleum hydrocarbon was not much commendable in the early 20th century. However, an increased trend was observed in the past few years. Further contribution in this aspect would help in stabilizing various global environmental as well as economic issues.


Assuntos
Poluentes Ambientais/metabolismo , Invenções/estatística & dados numéricos , Consórcios Microbianos/fisiologia , Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Biodegradação Ambiental , Poluentes Ambientais/isolamento & purificação , Desenho de Equipamento , Humanos , Patentes como Assunto , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação
11.
Bioresour Technol ; 182: 353-363, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25690682

RESUMO

Specific organic pollutants (SOPs) such as phenolic compounds, PAHs, organic pesticides, and organic herbicides cause health and environmental problems due to their excessive toxic properties and poor biodegradability. Low-cost biosorbents are considered as a promising alternative for conventional adsorbents to remove SOPs from water. These materials have several advantages such as high sorption capacities, good modifiability and recoverability, insensitivity to toxic substances, simple operation in the treatment processes. However, previous reports on various types of biosorbents for removing SOPs are still moderately fragmented. Hence, this paper provides a comprehensive review on using typical low-cost biosorbents obtained from lignocellulose and chitin/chitosan for SOPs adsorption. Especially, their characteristics, biosorption mechanism together with utilization for eliminating SOPs are presented and discussed. The paper also gives a critical view regarding future applications of low-cost biosorbents in SOPs-contaminated water treatment.


Assuntos
Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/economia , Adsorção , Biodegradação Ambiental , Quitina/química , Quitosana/química , Custos e Análise de Custo , Lignina , Praguicidas/isolamento & purificação , Fenóis/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Purificação da Água/métodos
12.
Anal Bioanal Chem ; 406(26): 6599-606, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25168113

RESUMO

In this contribution we introduce phase-optimized columns for highly efficient liquid chromatographic separations in microfluidic glass chips. In phase-optimized liquid chromatography the selectivity and geometry of the stationary phase are precisely adjusted to provide an optimal separation of a mixture of interest. The separation of nine polycyclic aromatic hydrocarbons under reversed-phase conditions was investigated. Standard HPLC was utilized to explore the retention parameters of each analyte on a set of five commercially available stationary phases. From these experiments the properties of an optimal on-chip column were calculated assuming a zero-void-volume performance for the chip chromatography. A phase-optimized on-chip column only 30 mm long provided baseline resolution of all signals within 4 min. The separation performance of a chip column comprising various stationary phases can be precisely predicted by a set of traditional HPLC experiments. The approach has great potential for the directed development of tailor-made chromatography chips for specific applications.


Assuntos
Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia de Fase Reversa/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/economia , Cromatografia de Fase Reversa/economia , Desenho de Equipamento , Técnicas Analíticas Microfluídicas/economia , Hidrocarbonetos Policíclicos Aromáticos/análise , Fatores de Tempo
13.
J Agric Food Chem ; 62(32): 8051-9, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25025712

RESUMO

A new solid-phase extraction (SPE) format was demonstrated, based on eggshell membrane (ESM) templating of the mixed hemimicelle/admicelle of linear alkylbenzenesulfonates (LAS) as an adsorbent for the enrichment of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in environmental aqueous samples. The LAS mixed hemimicelle/admicelle formation and SPE of the target PAHs were conducted simultaneously by adding the organic target and LAS through a column filled with 500 mg of ESM. The effect of various factors, including LAS concentration, solution pH, ionic strength, and humic acid concentration on the recoveries of PAHs were investigated and optimized. The results showed that LAS concentration and solution pH had obvious effect on extraction of PAHs, and the recoveries of PAHs compounds decreased in the presence of salt and humic acid. Under the optimized analytical conditions, the present method could respond down to 0.1-8.6 ng/L PAHs with a linear calibration ranging from 0.02 to 10 µg/L, showing a good PAHs enrichment ability with high sensitivity. The developed method was used satisfactorily for the detection of PAHs in environmental water samples. The mixed hemimicelle/admicelle adsorbent exhibited high extraction efficiency to PAHs and good selectivity with respect to natural organic matter and was advantageous over commercial C18 adsorbent, for example, high extraction yield, high breakthrough volume, and easy regeneration.


Assuntos
Carcinógenos Ambientais/isolamento & purificação , Casca de Ovo/química , Monitoramento Ambiental/métodos , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Ácidos Alcanossulfônicos/química , Animais , Carcinógenos Ambientais/análise , Carcinógenos Ambientais/química , Galinhas , China , Casca de Ovo/ultraestrutura , Monitoramento Ambiental/economia , Indústria de Processamento de Alimentos/economia , Substâncias Húmicas/análise , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Resíduos Industriais/economia , Limite de Detecção , Membranas/química , Membranas/ultraestrutura , Micelas , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Reprodutibilidade dos Testes , Extração em Fase Sólida , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
14.
Food Chem ; 146: 597-602, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24176386

RESUMO

This study aims at developing a method for the determination of 16 polycyclic aromatic hydrocarbons (PAHs) in rice grain samples by combining the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method and determination by gas chromatography-mass spectrometry (GC-EI-MS). Quantification limits ranging from 1 to 5µgkg(-1) were obtained. Recoveries ranged from 70% to 106% for most of the 16 PAHs under analysis. The optimised methodology was applied to assess safety concerning the content of PAHs in white and parboiled rice samples, dried by gas and wood burning. Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the samples, naphthalene and phenanthrene were detected in all of them. Since cereals have been shown to be an important source of PAHs in the diet, methods that perform the evaluation of the quality of this food group become relevant.


Assuntos
Contaminação de Alimentos/análise , Oryza/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Sementes/química , Extração em Fase Sólida/métodos , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida/economia
15.
Environ Technol ; 34(17-20): 2633-48, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24527625

RESUMO

Metallurgy is an industrial activity that is one of the largest contributors to soil contamination by metals. This contamination is often associated with organic compound contamination; however, little research has been aimed at the development of simultaneous processes for decontamination as opposed to treatments to heavy metals or organic compounds alone. This paper presents an efficient process to decontaminate the soils polluted with smelting by-products rich in Cu, Zn and polycyclic aromatic hydrocarbons (PAHs). A simultaneous treatment for metals and PAHs was also tested. The process is mainly based on physical techniques, such as crushing, gravimetric separation and attrition. For the finest particle size fractions, an acid extraction with H2SO4 was used to remove metals. The PAH removal was enhanced by adding surfactant during attrition. The total metal removals varied from 49% to 73% for Cu and from 43% to 63% for Zn, whereas a removal yield of 92% was measured for total PAHs. Finally, a technical-economic evaluation was done for the two processes tested.


Assuntos
Recuperação e Remediação Ambiental/métodos , Metais/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Solo/química , Ácidos Sulfúricos/química , Tensoativos/química
16.
Talanta ; 100: 207-16, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23141329

RESUMO

A simple, fast, and cost effective sample preparation procedure has been developed and validated for the determination of 15+1 European Union Polycyclic Aromatic Hydrocarbons (15+1 EU PAHs) in dried tea leave samples. Based on a critical assessment of several sample extraction/clean-up approaches, the method based on the ethyl acetate extraction followed by the use of PAHs dedicated cartridges with molecularly imprinted polymers (MIPs) has been found as an optimal alternative in terms of time demands and obtained good extract purity. For the final identification/quantification of target PAHs, two dimensional gas chromatography coupled to a time-of-flight mass spectrometry (GC×GC-TOFMS) was used. The performance characteristics of the overall analytical method for individual PAHs determined at three spiking levels (0.5, 2.5 and 5 µg kg(-1)) were in following ranges: limits of quantitation (LOQs) 0.05-0.2 µg kg(-1), repeatabilities 2-9%, and recoveries 73-103%. The recoveries achieved by the newly developed sample preparation procedure when employed for naturally contaminated sample ("incurred" PAHs) were comparable to those obtained by other routinely used approaches employing sonication and/or pressurised liquid extraction for sample analytes isolation. The validated method was subsequently used for the determination of selected genotoxic PAHs in 36 samples of black and green tea obtained from the Czech retail market. The levels of ΣPAH4 (sum of benzo[a]anthracene (BaA), chrysene (CHR), benzo[b]fluoranthene (BbFA) and benzo[a]pyrene (BaP)) in black and green tea leaves ranged from 7.4 to 700 µg kg(-1) and from 4.5 to 102 µg kg(-1), respectively. Contamination of tested tea samples by BaP was in the range of 0.2-152 µg kg(-1).


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Chá/química , Análise Custo-Benefício , Análise de Alimentos/economia , Cromatografia Gasosa-Espectrometria de Massas/economia , Impressão Molecular , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Polímeros/síntese química , Segurança , Extração em Fase Sólida , Solventes/química , Fatores de Tempo
17.
Environ Pollut ; 162: 457-65, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22172938

RESUMO

A comprehensive, weight-of-evidence based ecological risk assessment approach integrating laboratory and in situ bioaccumulation and toxicity testing, passive sampler devices, hydrological characterization tools, continuous water quality sensing, and multi-phase chemical analyses was evaluated. The test site used to demonstrate the approach was a shallow estuarine wetland where groundwater seepage and elevated organic and inorganic contaminants were of potential concern. Although groundwater was discharging into the surficial sediments, little to no chemical contamination was associated with the infiltrating groundwater. Results from bulk chemistry analysis, toxicity testing, and bioaccumulation, however, suggested possible PAH toxicity at one station, which might have been enhanced by UV photoactivation, explaining the differences between in situ and laboratory amphipod survival. Concurrently deployed PAH bioaccumulation on solid-phase micro-extraction fibers positively correlated (r(2) ≥ 0.977) with in situ PAH bioaccumulation in amphipods, attesting to their utility as biomimetics, and contributing to the overall improved linkage between exposure and effects demonstrated by this approach.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Invertebrados/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Invertebrados/química , Invertebrados/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Extração em Fase Sólida , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/metabolismo
18.
Environ Technol ; 32(1-2): 183-95, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21473281

RESUMO

Reference materials play a key part in systems of inspection and quality control of results of analytical measurements. The main limitation in using certified reference materials (CRM) is their high price, which results from the long and costly process of producing the reference material. An alternative to costly CRM materials is the employment of laboratory reference materials, particularly for interlaboratory control of measurement results and procedures. Under the auspices of the Chair of Analytical Chemistry at the Chemical Department of Gdansk University of Technology, research on the development of new reference materials is being conducted. At present, the research is aimed at producing a new laboratory reference material (LRM): 'Soil 1. Baseline and Highly Elevated Concentrations of Metals and Polycyclic Aromatic Hydrocarbons' - LRM soil 1. This paper presents the production stages of the developed laboratory reference material: acquisition of raw material from soil samples taken from the environment of the Tri-city (in Polish, Trójmiasto Gdansk, Sopot, Gdynia) bypass road, homogenization and subsequent dosage into appropriate containers, tests of homogeneity of sampled material within one container and between containers, based on the results of the determination of selected parameters (total carbon, content of optional metals - Hg, Fe, Cu Zn, Mn, Mg, water content, content of PAH-group analytes). The obtained results of homogeneity tests of the proposed future laboratory reference material have confirmed the homogeneity of soil samples within a container and between containers. Currently, interlaboratory tests are being carried out to determine the reference value.


Assuntos
Reagentes de Laboratório/normas , Metais Pesados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Cromatografia Gasosa-Espectrometria de Massas , Reagentes de Laboratório/economia , Metais Pesados/química , Metais Pesados/isolamento & purificação , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Padrões de Referência , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Espectrofotometria Atômica/métodos , Espectrofotometria Atômica/normas
19.
J Hazard Mater ; 178(1-3): 906-16, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20211519

RESUMO

Screening-level ecological and human health assessments were performed for polycyclic aromatic hydrocarbon (PAH) contamination in the sediments of 19 stormwater detention ponds located in coastal South Carolina. For ecological screening benchmarks, we used threshold and probable effect concentrations (TEC and PEC) derived from consensus-based sediment quality guidelines for individual PAH analytes and equilibrium partitioning sediment benchmarks-toxic units (SigmaESB-TU) derived for PAH mixtures. For human health benchmarks, we used preliminary remediation goals (PRGs). Sediments of five stormwater ponds (four commercial ponds and one residential pond with a large drainage area) exceeded PEC values for several PAH analytes and the SigmaESB-TU safe value of 1 for PAH mixtures. These same five stormwater ponds also exceeded the PRG values for five carcinogenic PAH analytes. These results suggest that the PAH levels in sediments from certain commercial and residential ponds have the potential to pose moderate to high risks for adverse, chronic effects to benthic organisms in situ and an increased risk of cancer to humans ex situ following excavation and on-site disposal. We recommend that sediment from these stormwater ponds be tested prior to excavation to determine the appropriate method of disposal. We also recommend that regulatory agencies enforce guidelines for periodic sediment removal as this should reduce both in situ and ex situ risks resulting from sediment PAH exposure.


Assuntos
Poluição Ambiental/análise , Sedimentos Geológicos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Carcinógenos/análise , Carcinógenos/toxicidade , Cromatografia Líquida de Alta Pressão , Humanos , Indicadores e Reagentes , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Medição de Risco , South Carolina , Espectrofotometria Ultravioleta , Microbiologia da Água , Poluentes Químicos da Água/isolamento & purificação
20.
Water Res ; 44(3): 681-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19822345

RESUMO

A molecularly imprinted polymer (MIP) adsorbent for carcinogenic polycyclic aromatic hydrocarbons (PAHs) was prepared using a non-covalent templating technique. MIP particles sized from 2 to 5 microm were synthesized in acetonitrile by using six PAHs mix as a template, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. When compared with the non-imprinted polymer (NIP), the MIP showed an excellent affinity towards PAHs in aqueous solution with binding capacity (B(max)) of 687 microg g(-1)MIP, imprinting effect of 6, and a dissociation constant of 24 microM. The MIP exhibited significant binding affinity towards PAHs even in the presence of environmental parameters such as dissolved organic matter (COD) and total dissolved inorganic solids (TDS), suggesting that this material may be appropriate for removal of carcinogenic PAHs. The feasibility of removing PAHs from water by the MIP demonstrated using groundwater spiked with PAHs. In addition, the MIP reusability without any deterioration in performance was demonstrated at least ten repeated cycles.


Assuntos
Carcinógenos/isolamento & purificação , Impressão Molecular/métodos , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Polímeros/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Conservação dos Recursos Naturais , Meio Ambiente , Humanos , Microscopia Eletrônica de Varredura , Impressão Molecular/economia , Solo/análise , Propriedades de Superfície , Temperatura , Fatores de Tempo , Abastecimento de Água/análise
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