Analysis Of Polycyclic Aromatic Hydrocarbons Research Articles

Contamination of Scots pine forests with polycyclic aromatic hydrocarbons on the territory of industrial city of Siberia, Russia.

Anthropogenic contamination with polycyclic aromatic hydrocarbons (PAH) coming from a powerful aluminum smelter has been estimated by the accumulation of these substances (17 substances: phenanthrene, fluoranthene, pyrene, chrysene, acenaphthylene, acenaphthene, anthracene, fluorene, benz[а]anthracene, benz[b]fluoranthene, benz[k]fluoranthene, benz[а]pyrene, benz[е]pyrene, perylene, indeno[1,2,3-c,d]pyrene, benz[g,h,i]perylene, dibenz[a,h]anthracene) in needles of Scots pine (Pinus sylvestris L.) in the residential areas of Bratsk, East Siberia, Russia. It has been found that the total PAH amount reaches the maximum values (982ng/g) in the needles of trees growing in a residential zone, remote from the smelter up to 10km (Central Urban District), where more than half of the city's population lives. On the territory remote up to 25km (Padunsky District), PAH needle levels decline, but are still 14.5-17.5 times higher than the background ones and at a distance of 45km (Pravoberezhny District), they still exceed background levels (30ng/g) by 4.7-8.1 times. Qualitative analysis of PAH showed the prevalence (up to 90% of the total amount) of 3-4 ring PAHs in pine needles on the entire studied territory. PAH concentrations increase when approaching the smelter with the highest values in the Central City District. Within the urban area, the content of PAHs with 5-6 rings (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene (B[a]P), benz[a]anthracene, dibenz[a,h]anthracene, indeno[1,2,3-c,d]pyrene, benzo[g,h,i]perylene) is also significantly increased. In the Central District, needle concentration of B[a]P, which is a class 1 carcinogen, exceeds the background one by 22 times, the Padunsky District-by 7 times, and the Pravoberezhny District-by 3 times. In the territories of the Central Districts, needle level of perylene, which is a marker of territory pollution by aluminum smelter emissions, is 18 times, the Padunsky District-by 10 times, Pravoberezhny District-by 2.5-3 times higher than in the background, where the perylene level is below the detection limit (< 0.2ng/g).

Polycyclic aromatic hydrocarbons (PAHs) in urban soils of Ahvaz metropolis; contamination, composition, distribution, potential sources, and cancer risk

ABSTRACTSixteen polycyclic aromatic hydrocarbons (PAHs) were investigated in urban soils of Ahvaz metropolis to assess the contamination, distribution, potential sources, and related health risks for local residents. For this purpose, a total of 39 topsoil samples from different parts of the city were collected and analyzed for PAHs using gas chromatography–mass spectrometry. PAHs analysis revealed that 4 -rings PAHs are the dominant compounds. Distribution maps revealed that outlet roads of the city and an area in city center, particularly an industrial area at Southwest of the city, West Saheli street, Pasdaran Blvd, Ahvaz-Ramhormoz Police Station, Khorramshahr bus terminal, and Daneshgah Square, are the contamination hotspots. PAHs diagnostic ratios and principal component analysis (PCA) showed both petrogenic and pyrogenic sources for these compounds, although, the results indicated the dominance of pyrogenic (combustion) origin, particularly traffic emission, incomplete combustion of fossil fuels and gasoline emissions. Furthermore, calculation of toxic equivalents and cancer risk showed a high carcinogenic risk especially through dermal contact and ingestion pathways; however, compared with adults, children faced more cancer risk in their daily life through their unconscious ingestion and dermal contact pathway.

Three-dimensional multi-walled carbon nanotubes@g-C3N4@Fe3O4nanocomposites-based magnetic solid phase extraction for the determination of polycyclic aromatic hydrocarbons in water samples

In this study, three-dimensional multi-walled carbon nanotubes@g-C3N4@Fe3O4 nanocomposites (3D MWNTs@g-C3N4@Fe3O4 nanocomposites) were prepared and used as a novel magnetic solid phase extraction (MSPE) sorbent for the analysis of 16 polycyclic aromatic hydrocarbons (PAHs). The novel nanocomposites were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), and vibrating sample magnetometer (VSM) methods. To achieve the best extraction efficiency, several experimental parameters, including sorbent amount, extraction time, stirring rate, ionic strength, desorption solvent, desorption volume and desorption time, were optimized. Under the optimized preparation and extraction conditions, the proposed method showed the limits of detection (LODs) for polycyclic aromatic hydrocarbons (PAHs) were found to be in the range of 0.001–0.5 μg L−1, limits of quantification (LOQs) were in the range of 0.005–0.8 μg L−1 and their relative standard deviations (RSDs) were lower than 5.0%. The proposed MSPE method was applied successfully in the analysis of PAHs in rainwater, river water and industrial wastewater samples. The recovery of the PAHs in all samples spiked with 5 g L−1 ranged from 82.4 to 116.9% with RSDs below 9.7%.

Polycyclic aromatic hydrocarbon exposure in seaside sparrows (Ammodramus maritimus) following the 2010 Deepwater Horizon oil spill

The seaside sparrow (Ammodramus maritimus) is an abundant and permanent resident of coastal salt marshes impacted by the 2010 BP Deepwater Horizon oil spill. Such terrestrial species are often overlooked in the aftermath of marine spills, despite the potential for long-term oil exposure. We sampled the livers of seaside sparrows residing in oiled and unoiled sites from 2011 to 2014 and quantified expression of cytochrome p450 1A (CYP1A), a gene involved in the metabolism of polycyclic aromatic hydrocarbons (PAHs). In August 2011, CYP1A expression was markedly higher in birds from an oiled site compared to an unoiled site, but differences had disappeared by June 2012. In June 2013, CYP1A expression was elevated compared to 2012 levels on all sites, including those collected from sites that had not been directly oiled during the spill. This rise in CYP1A expression was possibly due to Hurricane Isaac, which made landfall near our sites between the 2012 and 2013 sampling periods. CYP1A expression was significantly attenuated again in June 2014. We also collected sediment samples from the same marshes for a total concentration analysis of PAHs. The PAH concentrations in sediment samples exhibited a similar pattern to the CYP1A data, supporting the link between marsh PAHs and bird CYP1A expression. These results indicate that contamination from marine oil spills can immediately extend to terrestrial ecosystems, and that storms, weather, or other factors may influence subsequent spatial and temporal oil exposure for several additional years.

Ionization of Gas-Phase Polycyclic Aromatic Hydrocarbons in Electrospray Ionization Coupled with Gas Chromatography.

Herein, gas-phase polycyclic aromatic hydrocarbons (PAHs) as nonpolar compounds were ionized to protonated molecular ions [M + H]+ without radical cations and simultaneously analyzed using gas chromatography (GC)/electrospray ionization (ESI)-tandem mass spectrometry (MS/MS). The ionization profile, dissociation, and sensitivity were first investigated to understand the significant behavior of gas-phase PAHs under ESI. The formation of protonated molecular ions of PAHs was distinguished according to the analyte phase and ESI spray solvents. The protonated PAHs exhibited characteristic dissociations, such as H-loss, H2-loss, and acetylene-loss, via competition of internal energy. In addition, GC/ESI-MS/MS resulted in relatively lower concentration levels (better sensitivity) for the limits-of-detection (LODs) of PAHs than liquid chromatography (LC)/ESI-MS/MS, and it seems to result from the characteristic ionization mechanism of the gas-phase analyte under ESI. Furthermore, the LODs of gas-phase PAHs depended on molecular weight and proton affinity (PA). Consequently, we demonstrated the relationship among the analyte phases, sensitivities, and structural characteristics (molecular weight and PA) under ESI. The gas-phase PAHs provided enhanced protonation efficiency and sensitivity using GC/ESI-MS/MS, as their molecular weight and PA increased. Based on these results, we offered important information regarding the behavior of gas-phase analytes under ESI. Therefore, the present GC/ESI-MS/MS method has potential as an alternative method for simultaneous analysis of PAHs.

Polycyclic aromatic hydrocarbons (PAHs) associated with PM2.5 within boundary layer: Cloud/fog and regional transport

A study of PM2.5-associated PAHs analysis at Mount Lushan (1165m) was conducted to investigate the distributions of PAHs in PM2.5 and influences of cloud/fog. The main purpose was to quantify the main emission sources of PAHs and estimate regional transport effects within the boundary layer. Mount Lushan is located between the boundary layer and troposphere, which is an ideal site for atmosphere transport investigation. The concentrations of PAHs in PM2.5 were analyzed with GC–MS. The results showed that the volume concentration was 6.98ng/m3 with a range from 1.47 to 25.17ng/m3 and PAHs mass were 160.24μg/g (from 63.86 to 427.97μg/g) during the sampling time at Mount Lushan. The dominant compounds are BbF, Pyr and BP. In terms of aromatic-ring PAHs distributions, 4–6-ring PAHs are predominant, indicating that the high-ring PAHs tend to contribute more than low-ring PAHs in particulates. Due to frequent cloud/fog days at Mount Lushan, PAHs concentrations in the PM2.5 were determined before and after cloud/fog weather. The results demonstrated that the cloud/fog and rain conditions cause lower PAHs levels. Regression analysis was used for studying the relationship of PAHs distributions with meteorological conditions like temperature, humidity and wind. The results showed that the temperature and wind speed were inversely related with PAHs concentration but humidity had no significant relationship. Furthermore, backward trajectories and PCA combined with DR (diagnostic ratio analysis) were employed to identify the influences of regional transport and main emission sources. The results revealed that PAHs in PM2.5 were mainly affected by regional transport with the main emissions by mobile vehicle and steel industry, which contributed about 56.0% to the total PAHs in the area of Mount Lushan. In addition, backward trajectories revealed that the dominant air masses were from the northwest accounting for about one third of total PAHs.

Antibody Development and Immunoassays for Polycyclic Aromatic Hydrocarbons (PAHs)

Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous contaminants produced by natural or anthropogenic processes and found in various environment and food samples. A number of PAHs are carcinogenic and listed as priority pollutants in a variety of regulations. For a long time, much public attention has been drawn on PAHs due to the sensitive issue of environmental risks and food safety. In recent years, immunoassay methods have been applied in environmental and food analysis of PAHs and employed as highly sensitive, selective and cost-effective alternative to complement traditional chromatographic analysis. In this article, the rapid progress in the immunoassays for analysis of PAHs in food and environmental samples, such as selecting haptens, producing antibodies and developing immunoanalytical methods, has been reviewed. Since there was a comprehensive review published in 2002, this article is mainly focusing on the achievements since 2002 in this field. Some significant works before 2002 are also included. Although there have been quite a few antibodies and immunoassays for PAHs available, more novel antibodies and immunoanalytical methods are still welcome. Moreover, class-selective determinations and quantitative structure-activity relationship (QSAR) techniques are likely to play an important role in PAHs immunoassays in the future. Keywords: Immunoassay, ELISA, PAHs, benzo[a]pyrene, hapten, antibody.

Evaluating porewater polycyclic aromatic hydrocarbon-related toxicity at a contaminated sediment site using a spiked field-sediment approach.

Although the complexity of contaminant mixtures in sediments can confound the identification of causative agents of adverse biological response, understanding the contaminant(s) of primary concern at impacted sites is critical to sound environmental management and remediation. In the present study, a stock mixture of 18 polycyclic aromatic hydrocarbon (PAH) compounds was prepared to reflect the variety and relative proportions of PAHs measured in surface sediment samples collected from discrete areas of a historically contaminated industrial estuary. This site-specific PAH stock mixture was spiked into nontoxic in-system and out-of-system field-collected reference sediments in dilution series spanning the range of previously measured total PAH concentrations from the region. Spiked sediments were evaluated in 10-d Leptocheirus plumulosus tests to determine whether toxicity in laboratory-created PAH concentrations was similar to the toxicity found in field-collected samples with equivalent PAH concentrations. The results show that toxicity of contaminated sediments was not explained by PAH exposure, while indicating that toxicity in spiked in-system (fine grain, high total organic carbon [TOC]) and out-of-system (course grain, low TOC) sediments was better explained by porewater PAH concentrations, measured using an antibody-based biosensor that quantified 3- to 5-ring PAHs, than total sediment PAH concentrations. The study demonstrates the application of site-specific spiking experiments to evaluate sediment toxicity at sites with complex mixtures of multiple contaminant classes and the utility of the PAH biosensor for rapid sediment-independent porewater PAH analysis. Environ Toxicol Chem 2018;37:893-902. © 2017 SETAC.

Spatiotemporal Variation, Source Analysis, and Health Risk Assessment of Particle-bound PAHs in Urumqi, China

The purpose of the present study was to evaluate the polycyclic aromatic hydrocarbons (PAHs) in fine (PM2.5) and coarse (PM10) particles in five functional areas, namely, the traffic, industrial, residential, commercial, and educational areas, in Urumqi, a megacity in northwest China. Airborne PM10 and PM2.5 samples were collected from the five areas during heating (November 2015–March 2016) and non-heating (July–September 2016) periods, and 16 priority PAHs (Ʃ16‎PAHs) in the samples were quantified and analyzed. Over the study period, the average Ʃ16PAHs in the PM10 and PM2.5 were 116.97 ± 41.44 ng m–3 and 88.57 ± 31.22 ng m–3, respectively. During the heating period, Ʃ16PAHs in both of the fractions were more than 2.5 times those during the non-heating period, with the highest values found in the industrial area during the heating period and in the traffic area during the non-heating period. The northern part of the city had more PAH pollution than the southern part. The compositions of the particle-bound PAHs varied temporally and spatially, with 4-ring PAHs contributing more during the heating period than during the non-heating period and with 5- and 6-ring PAHs exhibiting the opposite trend. In addition, 4-ring PAHs contributed more in the industrial area, whereas 5- and 6-ring PAHs contributed more in the traffic area, reflecting the variety of emission sources. Principal component analysis and diagnostic molecular ratios showed that vehicular exhaust was the major source of PAHs during both periods at the traffic and central urban sites, while heavy-duty vehicular emissions and natural gas/biomass/coal combustion emissions dominated in the industrial area. The average Benzo[a]pyrene equivalent toxicity (BaPeq) ranged from 4.4 to 37.9 ng m–3, showing a generally similar spatiotemporal distribution with the Ʃ16PAHs.‎ The results showed that the lifetime excess cancer risk (LCR) during the heating period was higher than during the non-heating period and that people who lived around the industrial and traffic areas had a higher likelihood of getting lung cancer than residents in other parts of the city.

Determination of polycyclic aromatic hydrocarbons with molecular mass 302 in Standard Reference Material 1597a by reversed-phase liquid chromatography and stop-flow fluorescence detection.

The identification of isomeric polycyclic aromatic hydrocarbons (PAHs) in complex samples via reversed-phase liquid chromatography (RPLC) with fluorescence detection (FL) is normally based on matching the chromatographic retention times of suspected peaks of interest with reference standards. Since no spectral information is obtained during the chromatographic run, the accurate identification of co-eluting PAHs with similar chromatographic behaviors requires confirmation with additional chromatographic methods. This is particularly true for the analysis of PAH isomers with the relative molecular mass (MM, g/mol) 302. The work presented here explores the information content of room-temperature fluorescence spectra for the analysis of PAHs with MM 302 in the Standard Reference Material (SRM) 1597a. Fluorescence spectra were recorded under stop-flow conditions with the aid of a commercial HPLC system. Of the 21 MM 302 PAHs known to be present in the SRM 1597a, 20 were tentatively identified based on retention times and the presence of 18 was confirmed based on excitation and emission spectral profiles.

REMOVAL EFFICIENCY OF PAHs IN WASTEWATER: STATISTICAL EVALUATIONS WITH CHEMICAL-PHYSICAL INDICATORS

Polycyclic aromatic hydrocarbons (PAHs) are very hazardous compounds. This investigation is the third in a series of three experiments carried out in conventional wastewater treatment plants with regard to PAHs. The first experiment regarded the analysis of PAHs in a municipal wastewater sewage system and in the wastewater treatment plant (WWTP) effluent, followed by a comparison between the observed removal efficiency and FATE model (US-EPA) predictions. The second experiment was carried out in the same WWTPs and showed no evident degradation of PAHs after applying a mass balance estimation between the various types of sludge. The aim of the third experiment described in this paper, was to study PAHs in a more extensive area of wastewater, (with a higher population density and with higher PAH values in the wastewater). The evaluations were carried out in different periods of the in order to estimate the removal efficiency of PAHs. The concentrations measured were well below the legal limits, however in a few cases a statistical analysis was carried out in order to identify possible correlations between various chemical-physical indicators, such as logKow and logKH, and PAH removal yield, verified at different stages of the different treatment plants. A strong correlation resulted between the mechanical treatment removal yield and logKow and a very good correlation between yield measures after secondary sedimentation and logKH. This is because the process is strongly influenced by volatilization induced by air insufflation in the oxidation reactor.

Determination of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in some personal care products in Nigeria.

The study was carried out to determine the presence and concentration of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in some personal care products in Nigeria. Commonly used consumer care products grouped into four classes, namely: plastics, cosmetics, disinfectants and washing products, were purchased from some supermarkets in Ile-Ife, Nigeria. The solid samples were pulverized and the PAHs and OCPs were extracted with n-hexane and dichloromethane, respectively using Soxhlet extraction method, while the liquid samples were extracted using liquid-liquid extraction method. The quantitative and qualitative determinations were carried out using Gas Chromatography coupled with Flame Ionization Detector (GC-FID) for PAHs, and Gas Chromatography coupled with Electron Capture Detector (GC-ECD) for the OCPs. The results for PAHs analysis gave an overall mean concentration of 3259.10 ± 5223.16 μg g-1 for plastics and 8388.00 ± 7106.55 μg g-1 for cosmetics. Comparatively, the concentrations of PAHs in the cosmetic samples were higher than in plastics samples, while both values were greater than the recommended limits of PAHs in consumer care products as stipulated by the World Health Organization. For the OCPs, disinfectant samples had a total mean concentration of 10.65 ± 6.50 μg mL-1, while washing products had a total mean concentration of 35.31 ± 39.31 μg mL-1. The concentrations of OCPs in washing products were higher than their concentrations in disinfectant samples. The results of the OCPs in some samples were greater than Maximum Residual Limit (MRL) recommended by the European Commission. The study concluded that consumer care products used in this study contained PAHs and OCPs at levels that could be risky to human health if the consumer care products are not used with caution.

Controllable Growth of Nanoporous Metal Oxide Composites on Nickel-Titanium Alloy Fibers for Solid-Phase Microextraction of Polycyclic Aromatic Hydrocarbons

Abstract Hydrothermal oxidation was used to prepare a nickel-titanium alloy (NiTi) wire as the solid-phase microextraction fiber. The experimental results demonstrated that a nanoporous nickel-titanium oxide composite coating was in situ grown on the surface of NiTi substrate by direct oxidation in aqueous H2O2 solution at 80 °C. The resulting oxide composite coating included more nickel and less titanium. The prepared NiTi fiber with Ni-rich oxide coating was used to extract typical aromatic compounds coupled with HPLC-UV and exhibited good extraction selectivity for polycyclic aromatic hydrocarbons (PAHs). The key factors affecting extraction efficiency of PAHs were examined. Under the optimized conditions, the calibration curves were linear in the range of 0.05–400 ng mL−1 with correlation coefficients over 0.999, and the limit detection of PAHs ranged from 0.026 ng mL−1 to 0.056 ng mL−1. Furthermore, the relative standard deviations (RSDs) for intra-day and inter-day repeatability of the single fiber ranged from 4.8% to 6.2% and 5.4% to 6.5% for five replicate analyses of PAHs at the spiking level of 50 ng mL−1, respectively. The RSDs for the fiber-to-fiber reproducibility of five fibers prepared in different batches ranged from 6.4% to 8.4%. The developed method was suitable for selective enrichment and detection of target PAHs in environmental water samples with relative recoveries from 89.9% to 108.5% and RSDs = 8.1%. Moreover, this novel NiTi fiber was mechanically strong and chemically stable, and its preparation was precisely controllable.

Laser diagnostics and chemical kinetic analysis of PAHs and soot in co-flow partially premixed flames using diesel surrogate and oxygenated additives of n-butanol and DMF

Effects of oxygenated fuels on soot reduction strongly depend on the base fuel. Interesting candidates from oxygenated fuels in this respect include both n-butanol and 2,5-dimethylfuran (DMF), because they have already been used in diesel engines recently. However, information is rather limited on n-butanol and DMF added into a diesel fuel surrogate in fundamental flames to investigate the mechanism of soot reduction. In the current work, both n-butanol and DMF was successively added into diesel surrogate (80% n-heptane and 20% toluene in volume, named as T20) in co-flow partially premixed flames. The effects of different oxygenated structures on polycyclic aromatic hydrocarbons (PAHs) and soot were investigated at the same oxygen weight fractions of 4% and the same volume fractions of 20%. The diagnostics on PAHs, soot volume fractions and soot sizes were conducted by using both laser-induced fluorescence (LIF) and two-color laser-induced incandescence (2C-LII). A combined detailed kinetic model (n-heptane/toluene/butanols/DMF/PAHs) has been obtained in order to clarify the chemical effects of the different oxygenated fuels on PAHs formation. Results show that the reduced toluene content due to the addition of oxygenated fuels is the dominant factor for the reduction of soot, as compared with the base fuel of T20. The oxygenated structure of n-butanol has a higher ability to reduce PAHs and soot as compared with the addition of DMF. This is due to the fact that the consumption of DMF leads to much formation of C5H5 which enhances the formation of PAHs and subsequent soot. However, the formation of PAHs can be inhibited remarkably as blending n-butanol because only small hydrocarbons like C2H2 and C3H3 etc. are formed. The formation rate of A4 is more similar to that of soot in comparison with the smaller ring aromatics. For the size of soot particles, the distribution range is shrunk from 19–70 nm for T20 to 20–40 nm for the addition of oxygenated fuels. As compared to the effects of oxygenated structures, DMF20 presents a little wider distribution on soot sizes than that of B16.8. Some larger soot particles are detected in DMF20 flame but cannot be found in B20 flame.

Development of novel magnetic solid-phase extraction sorbent based on Fe3O4/carbon nanosphere/polypyrrole composite and their application to the enrichment of polycyclic aromatic hydrocarbons from water samples prior to GC–FID analysis

We describe a magnetic nanocomposite that consists of Fe3O4/carbon nanosphere/polypyrrole (Fe3O4/CNS/PPy). The synthesized nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy, and Fourier transform infrared spectroscopy. The nanocomposite was successfully applied to extract of the polycyclic aromatic hydrocarbons (PAHs) from water samples. Compared to Fe3O4/PPy, the Fe3O4/CNS/PPy nanocomposite exhibits improved properties in terms of extraction. The amount of adsorbent, salt effect, extraction time, desorption time, type, and the volume of desorption solvent were optimized. Following the desorption of the extracted analytes, the PAHs (i.e., naphthalene, 2-methylnaphthalene, 2-bromonaphthalene, fluorene, and anthracene) were quantified by gas chromatography–flame ionization detector. The PAHs can be determined in 0.05–100.00 ng mL−1 concentration range, with limits of detection (at an S/N ratio of 3) ranging from 0.01 to 0.05 ng mL−1. The repeatability of the method was investigated with relative standard deviations of lower than 9.9% (n = 5). Also, the recoveries from spiked real water samples were in the range of 88.9–99.0%. The results indicate that the novel material can be successfully applied for the extraction and analysis of PAHs from water samples.

Application of molecularly imprinted polymers for the analysis of polycyclic aromatic hydrocarbons in lipid matrix-based biological samples.

High-accuracy analyses of polycyclic aromatic hydrocarbons (PAHs) in lipid matrix-based biological samples are highly necessary. We investigated the cleanup performance of the commercially available molecularly imprinted polymers (MIPs) to analyze PAHs in various biological samples (i.e., butter, peanut oil, pork belly, and human umbilical cord), and compared this method with the commonly used gel permeation chromatography (GPC). After primary cleanup with a MIP or GPC column, the extracts were further cleaned with a neutral aluminum oxide column. Then, we measured 16 PAH congeners using gas chromatography-mass spectrometry. The MIP method allowed PAH recovery levels as high as those measured with the GPC methodto be obtained. More than 95% of the crude fats of butter, peanut oil, and pork belly were removed, although only ~50% were removed for human umbilical cord. The scan-mode ion chromatograms of the final extracts cleaned withthe MIP method had responses similar to solvent blank for the four types of samples, which were slightly better than those cleaned with GPC. Moreover, the PAH concentrations in the MIP operation blank were generally lower than those of GPC operation blanks. These results indicated that MIP could be applied to the analysis of PAHs in various lipid matrix-based biological samples. Graphical abstract The schematic diagram ofa molecularly imprinted polymer column and the elution curves of polycyclic aromatic hydrocarbons and crude fats of various biological samples.

Monitoring of pesticide residues in apples from the Greek market

In this study, a novel hollow mesoporous carbon spheres-based fiber (HMCSs-F) was fabricated to immobilize HMCSs onto a stainless steel wire for solid-phase microextraction (SPME). Characterization results showed that the HMCSs-F possessed a large specific surface area, high porosity and uniform pore size. To demonstrate the extraction performance, a series of polycyclic aromatic hydrocarbons (PAHs) was chosen as target analytes. The experimental parameters including extraction and desorption conditions were optimized. Compared to commercial fibers, the HMCSs-F exhibited better extraction efficiency for PAHs. More interestingly, a good extraction selectivity for PAHs from the complex matrix was observed in these HMCSs-F. The enhanced SPME performance was attributed to the unique pore structure and special surface properties of the HMCSs. Furthermore, under the optimum conditions, the limits of detection (LODs) for the HMCSs-F were in the range of 0.20–1.15 ng L−1 with a corresponding relative standard deviation that was below 8.6%. The method was successfully applied for the analysis of PAHs in actual environmental water samples with recoveries ranging from 85.9% to 112.2%. These results imply that the novel HMCSs-F have potential application in environmental water analysis.

Polyaniline-dicationic ionic liquid coated with magnetic nanoparticles composite for magnetic solid phase extraction of polycyclic aromatic hydrocarbons in environmental samples

In this present study, magnetic nanoparticles (MNPs) nanocomposites modified with polyaniline (PANI) coated newly synthesised dicationic ionic liquid (DICAT) forming MNP-PANI-DICAT were successfully synthesised as new generation material for magnetic solid phase extraction (MSPE). MNP-PANI-DICAT was characterised by FT-IR NMR, CHN, BET, SEM, TEM, and VSM techniques and the results were compared with MNP-PANI and native MNP. This new material was applied as a magnetic adsorbent for the pre-concentration and separation of polycyclic aromatic hydrocarbons (PAHs) due to the π–π interaction between polyaniline shell and dicationic ionic liquid (DICAT) with PAHs compounds. Under the optimal conditions, the proposed method was evaluated and applied for the analysis of PAHs in environmental samples using gas chromatography-mass spectrometry (GC-MS). The validation method showed good linearity (0.005–500µgL−1) with the coefficient of determination (R2) > 0.999. The limits of detection (LOD) and quantification (LOQ) of the developed method (MNP-PANI-DICAT-MSPE) were in the range of 0.0008–0.2086µgL−1 and 0.0024–0.6320µgL−1, respectively. The enrichment factor (EF) of PAHs on MNP-PANI-DICAT-MSPE were in the range of 7.546–29.632. The extraction recoveries of natural water, sludge, and soil samples were ranged from 80.2% to 111.9% with relative standard deviation (RSD) less than 5.6%. The newly synthesised MNP-PANI-DICAT possess good sensitivity, reusability, and fast extraction of PAHs under the MSPE procedure in various environmental samples.

Hollow mesoporous carbon spheres-based fiber coating for solid-phase microextraction of polycyclic aromatic hydrocarbons

In this study, a novel hollow mesoporous carbon spheres-based fiber (HMCSs-F) was fabricated to immobilize HMCSs onto a stainless steel wire for solid-phase microextraction (SPME). Characterization results showed that the HMCSs-F possessed a large specific surface area, high porosity and uniform pore size. To demonstrate the extraction performance, a series of polycyclic aromatic hydrocarbons (PAHs) was chosen as target analytes. The experimental parameters including extraction and desorption conditions were optimized. Compared to commercial fibers, the HMCSs-F exhibited better extraction efficiency for PAHs. More interestingly, a good extraction selectivity for PAHs from the complex matrix was observed in these HMCSs-F. The enhanced SPME performance was attributed to the unique pore structure and special surface properties of the HMCSs. Furthermore, under the optimum conditions, the limits of detection (LODs) for the HMCSs-F were in the range of 0.20–1.15ngL−1 with a corresponding relative standard deviation that was below 8.6%. The method was successfully applied for the analysis of PAHs in actual environmental water samples with recoveries ranging from 85.9% to 112.2%. These results imply that the novel HMCSs-F have potential application in environmental water analysis.

PAHs and DDTs in soil and sediment of inland water bodies of Warsaw city and its surroundings

Concentrations of polycyclic aromatic hydrocarbons (PAHs) and dichlorodiphenyltrichloroethane (DDT) in soil and sediment of inland water bodies in Warsaw and its surroundings, covering an area of 1200km2, were obtained during the work on the ‘Geochemical atlas of Warsaw and Εnvirons, 1:100,000’. Soil samples from a depth of 0–30cm were collected on a regular grid of 1×1km in Warsaw, and 2×2km outside its administrative boundaries. Sediment samples were collected from rivers, streams, ditches, canals, lakes and ponds. The distance between sampling sites in watercourses was 1,5km (within the borders of Warsaw) and 2km (outside the city). Analyses of PAHs and DDT compounds were made by gas chromatography–mass spectrometry (GC-MS), and gas chromatography with electron capture detection (GC-ECD), respectively.Within the borders of Warsaw the soil is characterised by elevated or high levels of PAHs and DDTs. Outside the city, especially to the east, large areas are differentiated by their low concentrations in soil. The highest PAH concentrations (>20,000mg/kg) were found in soil located near railway lines and in industrial and post-industrial areas. The highest contamination by p,p′-DDT and its metabolites is observed in soil of cultivated fields and gardens. The highest concentration of total DDTs (5400mg/kg) was found in allotment gardens in the eastern part of Warsaw. At some places, high predominance of p,p′-DDT concentration over the concentrations of its metabolites was observed, which indicates recent introduction of these compounds into soil. The PAH and DDT concentrations in sediment samples were lower than in soil. High PAH levels were observed mainly in the sediment of ponds and canals, and high DDTs concentrations were found in the sediment of ditches and canals.