Determination Of PAHs Research Articles

Fast and Reliable Extraction of Polycyclic Aromatic Hydrocarbons from Grilled and Smoked Muscle Foods

A fast and simple method for analysis of 14 PAHs in grilled and smoked muscle foods using acetonitrile based-extraction was validated. The optimum amounts of magnesium sulfate and sodium chloride that promoted phase separation of acetonitrile extract containing PAHs from water phase were selected by Central Composite Design. Matrix-matched calibration curves were constructed by adding different concentrations of PAHs and then subjected to extraction followed by HPLC with fluorescent detection. An excellent linearity for all compounds applying weighed least squares linear regression procedure was achieved. LODs and LOQs were lower than 0.12 and 0.39 ng g−1 respectively. Validation was done according to International Conference on Harmonization recommendations for 14 PAHs. The criteria for 4 EU marker PAHs (benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) established by European Comission Regulation No. 836/2011 was also accomplished. Repeatability and reproducibility were lower than 8 and 13.3%, and the most of recoveries fall in the range of 80–110% in different grilled and smoked muscle foods. The proposed method is a robust tool for determination of PAHs in grilled and smoked muscle foods, being easy to perform in short time.

Exposure assessment of particulate and gaseous pollutants emitted during surgery in operating rooms of different specialties

The objective of this study was to identify hazards that occur due to surgical practices and assess exposure to surgical smoke. We investigated nine surgical specialties in their corresponding operating rooms (ORs) for on-line measurements of pollutants and off-line determination of PAHs. Surgery for the face and dentistry generated the smallest particle size with a GMD of 23.3 nm. Also, the highest levels of the lung deposition surface area (5.8 ± 6.8 μm2/cm3), particulate matter of < 10 μm (PM10; 6.46 ± 5.34 μg/m3), PM2.5 (1.82 ± 1.01 μg/m3), and black carbon (0.10 ± 0.05 μg/m3) were seen with surgery of the face and dentistry. For gaseous pollutants, we observed that gastroenterology had the highest levels of CO2 (869 ± 112 ppm) and total volatile organic compounds (3.70 ± 1.00 ppm) compared to the other operating rooms. Levels of CO (3.40 ± 1.20 ppm) and formaldehyde (0.90 ± 0.51 ppm) were highest in the urology OR. Average total PAHs were mainly present in the gaseous phase with the highest concentrations of 746.6~1045.8 ng/m3 for gynecology. Our results showed that most pollutant levels were relatively low. However, gaseous PAHs emitted from surgical practices can reach levels that may pose important cancer risks in terms of occupational health.

Reduction of polycyclic aromatic hydrocarbons in common carp meat smoked in traditional conditions

ABSTRACTCommon carp meat was smoked in traditional conditions without filter and with zeolite, granular activated carbon, and gravel filters. The aim of this study was to determine the influence of using different filters in traditional smoking conditions on 16 polycyclic aromatic hydrocarbons from the Environmental Protection Agency list (16 US-EPA PAHs). Determination and quantification of PAHs were performed by gas chromatography–mass spectrometry (GC-MS). According to the obtained results, all examined samples of common carp meat smoked in traditional conditions were safe for consumers regarding to the European Commission Regulation on PAH content. After statistical analysis, the zeolite filter appeared to be the best one based on food safety of traditional production of smoked common carp meat. Application of any of these filters to produce smoked common carp meat in traditional conditions resulted in a safer product, as lower levels of PAHs were obtained.

Direct immersion solid-phase microextraction analysis of multi-class contaminants in edible seaweeds by gas chromatography-mass spectrometry

The present work aimed at the development of a simple and accurate direct immersion-solidphase microextraction-gas-chromatography-mass spectrometry (DI-SPME-GC-MS) method for simultaneous determination of PAHs, PCBs, and pesticide residues in edible seaweeds. As the target contaminants possess a wide range of physical-chemical properties, multivariate experimental design was used for method optimization. In particular, two different methods were optimized and validated: one that allows for simultaneous determination of all targets, and an ad hoc method for determination of hydrophobic analytes, a class that often poses a challenge for extraction from food matrices. Optimum conditions suitable for simultaneous quantitation of all targeted compounds, namely buffer at pH = 7.0, 20% acetone (v/v), 10% NaCl (w/w), 0.02% NaN3, 60 min DI extraction at 55 °C, and 20 min desorption at 270 °C, afforded limits of quantitation (LOQs) in the range of 1–30 μg kg−1, a wide linear range of 5–2000 μg kg−1, the attainment of satisfactory determination coefficients (R2˃0.99) with no significant lack of fit (p > 0.05) at the 5% level, and satisfactory accuracy and precision values. By modifying the extraction conditions to favor extraction of the most hydrophobic analytes (e.g. higher amount of organic modifier and pH, and lower salt content) lower LOQs were obtained for these compounds ranging from 0.2 to 13.3 μg kg−1. The established methods were then used for screening of commercial, edible dry seaweeds, with PCBs (≤16.0 ng g−1) and PAHs (≤15.5 ng g−1) detected in some samples. This method overcomes most challenges commonly encountered in dry sample analysis applications, and represents the first report of a DI-SPME method employing the matrix-compatible fiber for simultaneous multiclass and multiresidue analysis of seaweeds.

Chemically Deposited Sol–Gel Film on Porous TiO2 Nanotube Arrays as an Efficient and Unbreakable Solid-Phase Microextraction Fiber

In the present study, a novel technique was proposed to improve the performance of solid-phase microextraction fibers through the chemical deposition of polydimethylsiloxane/divinylbenzene film on modified TiO2 nanotube arrays substrate. Two different techniques, including the self-assembled monolayer of 3-mercaptopropyl trimethoxysilane and NaOH treatment, were examined to modify the surface of TiO2 nanotube arrays. The morphology of the prepared fibers was studied by scanning electron microscopy. The applicability of the novel fiber was evaluated through the headspace solid-phase microextraction of some polycyclic aromatic hydrocarbons as the model compounds followed by GC–MS determination. Influencing parameters on the extraction efficiency such as extraction time, temperature and salt content were studied and optimized. The thermal stability experiments demonstrated that the novel fiber was stable at 280 °C and reusable for more than 80 times without an obvious decrease in the extraction performance. The proposed method was successfully applied to the determination of PAHs in river water samples with good relative recoveries from 75.8 to 104.5% and the relative standard deviation values for all analytes were below 12%. Finally, the extraction performance of the prepared fiber was compared with those of commercially available fibers and similar previously reported fibers.

A novel method for PAHs in aqueous samples based on ultrasound-assisted solidified floating organic drop microextraction

A novel method for determining PAHs in river samples has been developed based on ultrasound-assisted solidified floating organic drop microextraction. The effect of several factors, such as volume of extracting solvent, volume of aqueous sample, sample temperature and extraction time, were evaluated and optimized. Best enrichment efficiency was obtained under the following experimental conditions: 60 μL of 1-undecanol added into a 30 mL sample solution at 40°C, and then extracted for 10 min in an ultrasonic bath. It showed a good performance for determining the PAHs in river samples and will be a promising method for the reliable determination of PAHs at a very low level in river.

Evaluation of Uncertainty Associated with Determination of Particle-bound PAHs in Ambient Area by TD-GC/MS and Soxhlet-GC/MS

Knowing the uncertainty associated with an analytical method is necessary to evaluating the quality of the results. In this work, the uncertainty associated with the analytical measurement of polycyclic aromatic compounds (PAHs) in ambient air using thermal desorption coupled with gas chromatography-mass spectrometry (TD-GC/MS) was evaluated. The study focused on analyses of the particulate phase (PM10), and the results were compared to those obtained with a conventional solvent extraction (Soxhlet-GC/MS). The main sources of the combined uncertainty were the calibration curve, recovery of the extraction stage, area or volume of the sample and volume of air. TD-GC/MS reported a lower combined uncertainty (< 10%) than Soxhlet-GC/MS (values between 11% and 18%) for the measurement of particle-bound PAHs in the air, which was primarily contributed by the recovery of the analyzed PAHs and the calibration curves.

Microwave-assisted-demulsification–dispersive liquid–liquid microextraction coupled with gas chromatography–mass spectrometry for the determination of PAHs in water

The MAD–DLLME method introduces microwave irradiation to achieve phase extraction, using a homemade glass flask as the extraction vessel.

PAHs in toasted bread: determination using microwave-assisted extraction and dispersive liquid–liquid microextraction followed by high-performance liquid chromatography

In the present study, a fast, simple, and efficient method for the determination of PAHs in toasted bread was developed using microwave-assisted extraction (MAE) and dispersive liquid–liquid microextraction (DLLME) followed by high-performance liquid chromatography (HPLC).

Facile in situ fabrication of oriented titania submicrorods embedded into a superelastic nickel–titanium alloy fiber substrate and their application in solid-phase microextraction

A novel NiTi@TiO2SR fiber was fabricated on a NiTi fiber substrate after annealing for the determination of PAHs in water.

Validation and sensitivity evaluation of the ID-GC-TOF-MS method for determination of PAHs in biogas

Validation and sensitivity evaluation of the ID-GC-TOF-MS method for determination of PAHs in biogas

Volatilization and oxidative artifacts of PM bound PAHs at low volume sampling (2): Evaluation and comparison of mitigation strategies effects

The artifacts induced by oxidative degradation and volatilization were assessed with regards to determination of particulate atmospheric PAHs collected at low volume conditions (2.3 m3 h−1) according to the EU Reference Method EN 12341:2014. In order to evaluate the oxidative degradation, PAH measures carried out through collecting airborne particulate with and without ozone denuders were examined. Simultaneously, the influence of volatilization was investigated by comparing concentrations of PAHs in particulate samples collected over 24-h and 12-h using conventional instruments. Summer and winter/spring campaigns were carried out in order to assess the influence of environmental contour on the artifact processes. Oxidative degradation led to a general decrease of PAH concentrations in both periods; in particular, the highest losses were observed for benzo[a]pyrene and perylene reaching, in average, ca. 20%. In the summer, the effect of volatilization exceeded that of oxidative degradation for light PAHs up to benzo[e]pyrene. In the winter/spring time, the influence of both artifact typologies could be mitigated by splitting the normal 24-h collection interval starting at midnight into two 12-h intervals. A mitigation of the losses could even be obtained by fixing the start time sampling fixed at noon or in the first hours of the day. Finally, the feasibility of collecting PAHs through prolonged sampling (>1 month) at the flow rate of 1.1 L min−1 was preliminarily investigated. Results indicated that this approach is unsuitable for minimizing the oxidative artifacts.

Amino-silica/graphene oxide nanocomposite coated cotton as an efficient sorbent for needle trap device

Cotton and silica are easily available and plentiful natural materials, with significant sorptive properties, which can be provided easily at low prices. In this research, a novel and effective sorbent was synthesized by covalent attachment of amino-silica/graphene oxide nanocomposite to the cotton (Cot/GO/Si) and packed into a stainless steel needle for preparation a needle trap device (NTD). The nanocomposite sorbent was characterized by SEM and FT-IR. The Cot/GO/Si packed NTD was used for direct extraction of PAHs from polluted soil samples, followed by GC-FID measurement. Different affecting experimental variables, including extraction temperature, flow rate, desorption time and temperature were studied and optimized. Under the optimal conditions, good linearity of the calibration curves (R2 > 0.99) was obtained over the concentration range of 0.01–1.0 μg g−1. The limits of detection, limits of quantification and relative standard deviations were found to be in the ranges of 0.05–0.17 ng g−1, 0.2–0.6 ng g−1 and 9.7–15.4% (n = 6), respectively. Finally, the proposed NTD-GC-FID method was successfully applied for the extraction and determination of PAHs in contaminated soil samples.

Solvent bar micro-extraction (SBME) based determination of PAHs in seawater samples

Measuring the impact of PAHs in seawater samples is often difficult due to the low concentrations in which they appear and the complexity of the sample matrix. Traditional methods for sample preparation such as liquid-liquid extraction and solid phase extraction require the use of excessive amounts of solvents and reagents, and sample handling. In this work, hollow fiber liquid phase micro-extraction (HFLPME), in the configuration of solvent bar micro-extraction (SBME), was proposed as an environmentally friendly and more effective tool, for the extraction of the 16 priority PAHs from seawater samples. Extraction was conducted using hexane as a solvent. Enrichment factors from 45 to 163 were obtained after 60min at a stirring rate of 500rpm in the sample. Moreover, a negative linear relationship was observed between the enrichment factor and the molecular weight of the PAHs. Under optimized conditions, the limits of detection were in the range from 0.21 to 0.82ngL−1, the method showed a linear response up to 500μgL−1, and the average relative standard deviation for seawater samples spiked with 5ngL−1 was 11.6%. After calibration, the SBME was applied to extract PAHs in seawater samples from the Bay of Cadiz (SW Spain), showing an average recovery of 99%. In conclusion, the SBME is an environmentally friendly, one-step alternative for sample preparation in the determination of PAHs in seawater samples.

Determination of PAHs by ultra fast liquid chromatography using a core-shell technology – Application to their determination after using biochar as adsorbent

The C18 column (250mm×4.6mm) packed with 5μm core-shell particles was used in an effort to optimize the separation of 8 polycyclic aromatic hydrocarbons under very low pressure values (44–52bars), low temperature (16°C) and in 13min. Chromatogram and peaks of each polycyclic aromatic hydrocarbon studied, obtained using an ultra fast liquid chromatography fitted with this column and equipped with a diode array detector, were compared with those obtained using two other traditional C18 columns, packed with fully porous 5μm particles, usually used in our laboratory and specifically designed for the separation of polycyclic aromatic hydrocarbons. Thinnest peaks, highest sensitivity and efficiency are the main results related to the core-shell technology of the recent Kinetex column compared to more common C18 columns due to the bed uniformity and packing quality of the recent core-shell column. On the other hand, reduced retention time was highlighted for each polycyclic aromatic hydrocarbon using the column packed with core-shell particles resulting from the lower surface area of these particles compared to the totally porous particles of the both other columns used. Limits of detection and quantification, linearity range and repeatability were determined for the method developed with the core-shell column. A practical application was realized by evaluating the sorption capacity of the 8 polycyclic aromatic hydrocarbons studied in mixture using a biochar made from woody plants. To this end, the biochar was mixed with aqueous solution spiked with the mixture of polycyclic aromatic hydrocarbons and a kinetic study of their sorption was conducted. Sorption percentage was higher than 89% for each polycyclic aromatic hydrocarbon studied showing that the studied biochar could be good and low cost alternative products for the sorption of this type of pollutants.

Simultaneous determination of PAHS, nitro-PAHS and quinones in surface and groundwater samples using SDME/GC-MS

Environmental contamination by PAHs and their derivatives can cause damage to human health due to the carcinogenic and mutagenic potential of these compounds. This work proposes a new method for simultaneous determination of PAHs, nitro-PAHs and quinones in surface and groundwater samples employing gas chromatography coupled to mass spectrometry (GC–MS) after single-drop microextraction (SDME). The extraction step using SDME was optimized and it was found that the best experimental conditions for 10mL samples are: drop volume of 1.0μL, toluene as extraction solvent, and stirring time of 30min at 200rpm. The limits of detection obtained were from 0.01 to 0.03μgL−1 for PAHs, from 0.26 to 1.07μgL−1 for nitro-PAHs and from 6.96 to 468μgL−1 for quinones. The limits of quantification obtained were from 0.05 to 0.09μgL−1 for PAHs, from 1.24 to 4.31μgL−1 for nitro-PAHs and from 23.2 to 1559μgL−1 for quinones. For intraday precision, the maximum value obtained for RSD was 19% and for interday precision was 18.7%. The accuracy was verified using addition/recovery tests and the recoveries achieved varied from 36% to 152% for PAHs, from 23% to 103% for nitro-PAHs and from 48% to 134% for quinones. Eight PAHs, six nitro-PAHs and two quinones were detected and quantified in surface and groundwater samples. The average concentrations obtained were 0.70μgL−1 (naphthalene) for PAHs, 1605μgL−1 (1,2-naphthoquinone) for quinones and 5.61μgL−1 (1-nitropyrene) for nitro-PAHs. Indeed, the proposed method showed good sensitivity, linearity, precision and accuracy for the determination of PAHs, nitro-PAHs and quinones in water samples.

Determination of airborne PAHs using passive sampling with 2,6 diphenyl-p-phenylenoxide as adsorbant

The Journal of the National Science Foundation of Sri Lanka publishes the results of research in all aspects of Science and Technology. The journal also has a website at http://www.nsf.gov.lk/. 2021 Impact Factor: 0.682The JNSF provides immediate open access to its content on the principle that making research freely available to the public supports a greater global exchange of knowledge.Cover :Leatherback (a), green (b - adult &amp; f - hatchling), hawksbill (c) and olive ridley (d) turtles who nest in Sri Lankan beaches, green turtle crawl marks (e) and by-catch of sea turtles in fisheries (c &amp; d)Photo credits: SJ Perera (a &amp; c), WPN Perera (b &amp; e), K Ekaratne (d &amp; f)

PAHs in animal tissues – the analytics of PAHs in new reference materials and their homogeneity

Extraction and determination of PAHs in biological matrices of new reference materials, and determination of certified values and homogeneity of these materials are described.

Binary mixed solvent-based solvent demulsification-dispersive liquid-liquid microextraction coupled with gas chromatography-tandem mass spectrometry in determination of polycyclic aromatic hydrocarbons in water samples

A method of binary mixed solvent-SD-DLLME with GC-MS/MS was developed for the determination of PAHs in water samples.

Vehicular Tire as Potential Adsorbent for the Removal of Polycyclic Aromatic Hydrocarbons

ABSTRACTPolycyclic aromatic hydrocarbons (PAHs) are environmental pollutants, entering into various water and wastewater systems through various natural and anthropogenic activities. The aim of the work is to convert vehicular tires, a highly available waste material, into potential adsorbent for the removal of PAHs from aqueous solutions. The BET surface area of the prepared vehicular tire activated carbon is 643.86 m2/g. Removal of PAHs using activated carbons and the effect of various parameters such as contact time, adsorbent dose, temperature, and pH on the adsorption have been evaluated. The data were fitted to Freundlich and Langmuir isotherms and values of various constants were evaluated. In all the cases, Freundlich model was found to be better fitted. The equilibrium time for adsorption of PAHs was 120 min. The values of thermodynamic parameters, such as Gibb's free energy change ΔG°, enthalpy change ΔH°, and entropy change ΔS°, were calculated using adsorption equilibrium constants obtained from Langmuir isotherm. The thermodynamic data for adsorption of PAHs revealed spontaneity and endothermic nature of the adsorption process. The samples were analyzed using a UV–vis spectrophotometer for PAH determination. Mixture of sodium hydroxide and ethanol in different proportions was tried for desorption of PAHs and 50% ethanolic NaOH solution was most effective. The developed activated carbon demonstrates good adsorption and desorption capabilities for PAHs, indicating towards its suitability for use in the treatment processes of various industrial effluents or water streams containing PAHs.