Nitropolycyclic Aromatic Hydrocarbons Research Articles

Antimutagenic potential of harpagoside and Harpagophytum procumbens against 1-nitropyrene.

Background:1-nitropyrene (1-NPy) is one of the most abundant nitro-polycyclic aromatic hydrocarbons particularly in diesel exhausts. It is a mutagenic and carcinogenic pollutant very widespread in the environment. So the discovery of antimutagenic agents is essential. Harpagophytum procumbens (HP) is traditionally used as anti-inflammatory and analgesic particularly against painful osteoarthritis. Harpagoside (HS), its major iridoid glycoside, is considered as the main active component.Objective:The aim of the present study was to evaluate the antimutagenic activity of HS and HP extracts against mutagenic activity of 1-NPy.Materials and Methods:The antimutagenic activity was investigated using the in vitro cytokinesis-block micronucleus assay in cultured human lymphocytes. Cells were exposed to HS or HP extracts before (pretreatment), during (co-treatment), and after (posttreatment) treatment with 1-NPy.Results:Results showed that HS significantly reduced the mutagenicity of 1-NPy in pretreatment and particularly in co-treatment, whereas all HP extracts significantly reduced the genotoxicity in the three protocols.Conclusion:These results suggested that HS was strongly involved in antimutagenic activity of HP extracts in co-treatment, but other components in HP extracts participated in this activity in pre- and post-treatment.

Concentrations and origins of nitro-polycyclic aromatic hydrocarbons and oxy-polycyclic aromatic hydrocarbons in ambient air in urban and rural areas in northern China

Twelve nitro-PAHs (nPAHs) and four oxy-PAHs (oPAHs) were measured in air samples for 12 months at 18 sites in urban settings, rural villages, or rural fields in northern China. The nPAH concentrations were higher in urban areas (1.3 ± 1.3 ng/m3), and nPAH/parent PAH ratios were higher (suggesting important contributions from motor vehicles and secondary formation) in urban sites than in rural villages. oPAHs are primarily emitted from solid fuel combustion and motor vehicles, and similar oPAH concentrations were found in urban areas (23 ± 20 ng/m3) and rural villages (29 ± 24 ng/m3). The high numbers of motor vehicles in Beijing and intensive industrial activity in Taiyuan and Dezhou caused higher nPAH concentrations. No spatial trend in oPAH concentrations was found in the rural villages, because similar oPAH mixtures are emitted from solild fuel combustion. The nPAH and oPAH concentrations were higher in the winter, and correlated with residential energy consumption and precipitation.

Effects of humidity and [NO3]/[N2O5] ratio on the heterogeneous reaction of fluoranthene and pyrene with N2O5/NO3/NO2.

Atmospheric 2-nitrofluoranthene (2-NFL) and 2-nitropyrene (2-NPY) were two important nitro-polycyclic aromatic hydrocarbons (NPAHs). Especially, 2-NFL was recognized to be the most abundant particle-associated NPAH (Ramdahl et al., 1986). In previous studies, these two products were observed in the gas-phase reaction between N2O5/NO3/NO2 and their parent polycyclic aromatic hydrocarbons (PAHs), while the heterogeneous reaction generated other nitro-PAH isomers (1, 3, 7, 8-NFL and 1-NPY) (Atkinson et al. 1990). To clarify the possible reasons for this difference, the heterogeneous reactions of suspended fluoranthene (FL) and pyrene (PY) particles under different relative humidity (RH; 0.5%-43%) and [NO3]/[N2O5] ratios were carried out. Under low humidity (0.5% RH) or a relatively high ratio of [NO3]/[N2O5], 2-NFL and 2-NPY were observed as the major nitro-FL isomers for the first time in the heterogeneous reaction. Decreasing the humidity or increasing the [NO3]/[N2O5] ratio in the reaction essentially increases the concentration radio of [NO3(g)]/[NO2(+)(aq)] on the particle surface (NO2(+) is derived from the ionization of N2O5). Thus, it can be concluded that under different atmospheric conditions, the change of [NO3(g)]/[NO2(+)(aq)] in the particle surface has an influence on the product distribution of FL and PY in the atmosphere. The experimental results provide evidence for the heterogeneous formations of particle-bound 2-NFL and 2-NPY. However, relative to the gas-phase formation, they will be negligible in the real atmosphere. 2-NFL and 2-NPY observed in the ambient particles should mainly derive from deposition of gas-phase reactions. Additionally, this study also clarifies the reason for different nitro-PAHs isomers observed between gas and particulate reactions.

Atmospheric pressure solid analysis probe coupled to quadrupole-time of flight mass spectrometry as a tool for screening and semi-quantitative approach of polycyclic aromatic hydrocarbons, nitro-polycyclic aromatic hydrocarbons and oxo-polycyclic aromatic hydrocarbons in complex matrices

A new screening and semi-quantitative approach has been developed for direct analysis of polycyclic aromatic hydrocarbons (PAHs) and their nitro and oxo derivatives in environmental and biological matrices using atmospheric pressure solid analysis probe (ASAP) quadrupole-time of flight mass spectrometry (Q-TOF-MS). The instrumental parameters were optimized for the analysis of all these compounds, without previous sample treatment, in soil, motor oil, atmospheric particles (ashes) and biological samples such as urine and saliva of smokers and non-smokers. Ion source parameters in the MS were found to be the key parameters, with little variation within PAHs families. The optimized corona current was 4µA, sample cone voltage 80V for PAHs, nitro-PAHs and oxo-PAHs, while the desolvation temperatures varied from 300°C to 500°C. The analytical method performance was checked using a certified reference material. Two deuterated compounds were used as internal standards for semi-quantitative purposes together with the pure individual standard for each compound and the corresponding calibration plot. The compounds nitro PAH 9-nitroanthracene and oxo-PAH 1,4-naphthalenedione, were found in saliva and urine in a range below 1µg/g while the range of PAHs in these samples was below 2µg/g. Environmental samples provided higher concentration of all pollutants than urine and saliva.

Calcium signaling and β2-adrenergic receptors regulate 1-nitropyrene induced CXCL8 responses in BEAS-2B cells

Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) are widespread environmental pollutants, generated from reactions between PAHs and nitrogen oxides during combustion processes. In the present study we have investigated the mechanisms of CXCL8 (IL-8) responses induced by 1-nitropyrene (1-NP) in human bronchial epithelial BEAS-2B cells, with focus on the possible importance of Ca2+-signaling and activation of β2-adrenergic receptors (β2AR). Ca2+-chelator treatment obliterated 1-NP-induced CXCL8 (IL-8) responses. 1-NP at 10μM (but not 1μM) induced a rapid and sustained increase in intracellular Ca2+-levels ([Ca2+]i). The early but not the later, sustained phase of 1-NP-induced [Ca2+]i was suppressed by beta-blocker treatment (carazolol). Moreover, inhibition of β2AR by blocking-antibody, beta-blocker treatment (ICI 118551) or siRNA transfection attenuated CXCL8 responses induced by 1-NP. The results confirm that PAHs may induce Ca2+-signaling also in BEAS-2B cells, at least partly through activation of β2AR, and suggest that both β2AR- and Ca2+-signaling may be involved in 1-NP-induced CXCL8 responses in bronchial epithelial cells.

Study of nitro-polycyclic aromatic hydrocarbons in particulate matter in Dongguan

Total suspended and size-segregated atmospheric particles were collected in four seasons at three representative points in different functional areas of Dongguan City. The detailed size distributions of six nitro-PAHs [2-nitrofluorene (2-NF), 9-nitroanthracene, 2-nitrofluoranthene (2-NFL), 3-nitrofluoranthene, 1-nitropyrene, and 2-nitropyrene (2-NP)] were determined by high-performance liquid chromatography (HPLC) with UV detection using a binary elution gradient (methanol and water). We used a toxicity assessment based on potency equivalency factors (PEFs) to estimate the inhalation risk of the particulate matter. The results showed that, aside from 2-NF and 2-NFL, the content of the other four nitro-PAHs in the microparticles (<0.4 μm) were more than 20%, a percentage significantly higher than other fractions of particulate matter. The seasonal distribution of nitro-PAHs shows that their concentrations were higher in the winter, while the PAH concentrations were higher in the summer. The study found that secondary formation (2-NFL and 2-NP) had a positive correlation with NO x and NO2, but a negative correlation with O3. The benzo[a]pyrene equivalent (BaPeq) toxicity of particulate matter in Dongguan City ranged from 0.04 to 2.63 ng m(-3), and the carcinogenic index ranged from 0.04 × 10(-6) to 2.39 × 10(-6). These values do not represent a serious threat to human health.

Assessment of nitro-polycyclic aromatic hydrocarbons in PM1 near an area of heavy-duty traffic

The objective of this research was to evaluate nitro-polycyclic aromatic hydrocarbons (NPAHs) associated with ultrafine airborne particles (PM1) in areas affected by vehicles in the metropolitan area of Porto Alegre (MAPA), RS, Brazil. Extraction, isolation/derivatization, and subsequently gas chromatography with electron capture detection (GC/ECD) were the techniques used to extract and determine NPAHs (1-nitronaphthalene, 2-nitrofluorene,3-nitrofluoranthene,1-nitropyrene, and 6-nitrochrysene) associated with PM1 Airborne particles (PM1) were collected using PTFE filters in a PM162M automatic sampler. The analytical method was validated by the Standard Reference Material – SRM 1649b – from the National Institute of Standards and Technology (NIST, USA). The results were consistent with the certified values. 3-NFlt and 6-NChr reached highest concentrations of 0.047ng·m−3 and 0.0284ng·m−3, respectively, in Sapucaia do Sul and Canoas. Seasonal variation showed higher NPAH concentrations in cold days. The NPAHs associated with PM1 were correlated with the pollutants nitrogen oxides and NPAHs with meteorological variables: temperature and wind speed. The results indicated that vehicles with diesel engines were influential. This was confirmed by the study of the ratios NPAHs/PAHs, 1-NPyr/Pyr, and 6-NChr/Chr.

Influence of Biomass Burning on the Levels of Atmospheric Polycyclic Aromatic Hydrocarbons and Their Nitro Derivatives in Chiang Mai, Thailand

ABSTRACTChiang Mai and several other provinces in northern Thailand have been annually facing air pollution problems during the dry season. Ten polycyclic aromatic hydrocarbons (PAHs); 19 nitropolycyclic aromatic hydrocarbons (NPAHs); and levoglucosan (LG), a marker for biomass burning, were quantified in total suspended particulates (TSP) collected in Chiang Mai during the dry, transition, and wet seasons in 2010. The concentrations of PAHs and NPAHs in the dry season were significantly higher than in the wet season. The [Benzo[a]pyrene (BaP)] – [benzo[ghi]perylene (BghiPe)] ratio, as an indicator of traffic, and the correlations of PAHs and NPAHs with LG showed that biomass burning significantly contributes to air pollution in the dry season. 9-Nitroanthracene (9-NA) was the most abundant NPAH which suggests that 9-NA is generated from biomass burning. We proposed the [9-NA] – [1-nitropyrene (1-NP)] ratio as a new indicator for assessing the contribution of biomass burning. Biomass burning was a major source of PAHs and NPAHs in the dry season, whereas vehicle exhaust was the main contribution in the wet season. The high carcinogenic risks in the dry season correlate with more harmful air conditions during this season. Thus, it is important to control biomass burning to reduce air-pollution-related health risks during the dry season in northern Thailand.

Conformational Control in the Population of the Triplet State and Photoreactivity of Nitronaphthalene Derivatives

Nitronaphthalene derivatives (NNDs) are among the most abundant volatile nitro-polycyclic aromatic hydrocarbons found in the Earth's atmosphere. Investigations of the atmospheric degradation processes show that photolysis is the major degradation pathway under ambient conditions. In this contribution, we present photochemical measurements and quantum-chemical calculations of three major NNDs. It is shown that the magnitude of the photodegradation and triplet quantum yields in 1-nitronaphthalene (1NN), 2-methyl-1-nitronaphthalene (2M1NN), and 2-nitronaphthalene (2NN) are inversely related to each other. In accord with a recent time-resolved and computation study (J. Phys. Chem. A 2013, 117, 6580) and in order to explain this striking observation we propose that these photochemical yields are largely controlled by (1) the conformational heterogeneity of the nitro-aromatic torsion angle, (2) the energy gap (spin-orbit coupling interaction) between the excited singlet state and the receiver triplet state, and (3) the topology of the excited singlet state in the Franck-Condon region of configuration space sampled at the time of excitation. A distribution of torsion angles closer to 90° leads to a higher photoreactivity. Methylation of the ortho position in 1NN to give 2M1NN increases the photoreactivity by 97%, while 2NN is largely photoinert. Conversely, the triplet yield decreases as the distribution of torsion angles gets closer to 90°: 0.93 ± 0.15 in 2NN, 0.64 ± 0.12 in 1NN, and 0.33 ± 0.05 in 2M1NN. These results suggest an important relationship between conformational heterogeneity and the photochemical fate of these NNDs. This structure-photoreactivity relationship is of relevance to current efforts aimed at modeling and understanding the distribution patterns of NNDs in the atmosphere and their overall contribution to air quality.

Analytical applications of electron monochromator-mass spectrometry

An electron monochromator (EM) produces an electron beam with a narrow energy distribution that can be utilized with mass spectrometry (MS). The history and development of the EM from an initial research design to a commercial model are reviewed along with MS research applications. An EM incorporated with a mass spectrometer showed significant improvement in sensitivity over traditional methods for negative-ion generation and selectivity for compounds with electrophilic character. Sensitivity of EM-MS has been shown to be 25 fg for hexachlorobenzene in positive-ion mode and 10 fg for nitrobenzene in negative-ion mode. Reports regarding the analysis of chlorinated compounds, explosives, pesticides, phthalates, polychlorodibenzo-p-dioxins, polycyclic aromatic hydrocarbons (PAHs), nitro-polycyclic aromatic hydrocarbons (NPAHs), antioxidants, and bacterial biomarkers are discussed. Additionally, theoretical methods to predict electron-capture properties are presented.

Short-term personal traffic-related exposures and biomarkers of nitro-PAH exposure and oxidative DNA damage

Background: Traffic attributed exposures including diesel exhaust exposures have been associated with cardiac-related health outcomes, respiratory disease, lung cancer, and overall mortality. However, few biomarker indicators of exposure have been identified. Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) have been considered as diesel exhaust specific compounds. Their metabolites, amino-PAHs, may be used as biomarkers of diesel exhaust exposure. Aim: Assess relationships between urinary amino-PAHs and vehicle exhaust exposures to examine their efficacy as biomarkers of internal dose, and relationships with oxidative DNA damage. Methods: Urine samples were collected pre- and post-shift, at the beginning and end of a work week from 95 male U.S trucking industry workers. We used repeated-measures analysis to assess total 1- and 2-aminonaphthalene (1-AN &amp; 2-AN) and 1-aminopyrene (1-AP) urinary concentrations with concurrent microenvironment particulate matter (PM­2.5), elemental and organic carbon (EC &amp; OC), and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG). Results: There was a suggestive association between daily PM2.5 ­­­levels and post-shift urinary 1 &amp; 2-AN levels with a 115.0 pg/ml increase (95% CI:-0.5, 230.1) associated with every IQR increase in PM­2.5, but there were no other associations with daily or mean PM­2.5, EC, or OC . There were significant associations between pre-shift levels of 1 &amp; 2-AN and post-shift 8-OHdG levels and between concurrent 1-AP and 8-OHdG levels with 4.64 (95% CI: 0.81, 8.45) and 3.29 (95% CI: 0.05, 6.59) µg/g urine creatinine increases in 8-OHdG levels per IQR increase in exposure biomarkers, respectively. Conclusions: Our findings suggest only weak associations of the urinary amino-PAHs with PM2.5 in this trucking industry population. However, amino-PAHs were significantly associated with 8-OHdG, suggesting that the internal dose markers may be more relevant to oxidative DNA damage than external measures of vehicular exhaust.

PM10 source apportionment in a Swiss Alpine valley impacted by highway traffic

Although trans-Alpine highway traffic exhaust is one of the major sources of air pollution along the highway valleys of the Alpine regions, little is known about its contribution to residential exposure and impact on respiratory health. In this paper, source-specific contributions to particulate matter with an aerodynamic diameter < 10μm (PM10) and their spatio-temporal distribution were determined for later use in a pediatric asthma panel study in an Alpine village. PM10 sources were identified by positive matrix factorization using chemical trace elements, elemental, and organic carbon from daily PM10 filters collected between November 2007 and June 2009 at seven locations within the village. Of the nine sources identified, four were directly road traffic-related: traffic exhaust, road dust, tire and brake wear, and road salt contributing 16%, 8%, 1%, and 2% to annual PM10 concentrations, respectively. They showed a clear dependence with distance to highway. Additional contributions were identified from secondary particles (27%), biomass burning (18%), railway (11%), and mineral dust including a local construction site (13%). Comparing these source contributions with known source-specific biomarkers (e.g., levoglucosan, nitro-polycyclic aromatic hydrocarbons) showed high agreement with biomass burning, moderate with secondary particles (in winter), and lowest agreement with traffic exhaust.

UVA Photoirradiation of Nitro-Polycyclic Aromatic Hydrocarbons—Induction of Reactive Oxygen Species and Formation of Lipid Peroxides †

Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) are a class of genotoxic environmental contaminants. We have long been interested in determining the mechanisms by which nitro-PAHs induce genotoxicity. Although the metabolic activation of nitro-PAHs leading to toxicological activities has been well studied, the photo-induced activation of nitro-PAHs has seldom been reported. In this paper, we report photo-induced lipid peroxidation by 19 nitro-PAHs. The results indicated that all but two of the nitro-PAHs can induce lipid peroxidation. Mechanistic studies suggest that lipid peroxidation by nitro-PAHs is mediated by free radicals generated in the reaction. There was no structural correlation between the nitro-PAHs and their ability to induce lipid peroxidation upon UVA irradiation, or between the HOMO-LUMO gap and the ability to cause lipid peroxidation. Most of the nitro-PAHs are less potent in terms of causing lipid peroxidation than their parent PAHs. The lack of correlation is attributed to the complex photophysics and photochemistry of the nitro-PAHs and the yield of reactive oxygen species (ROS) and other factors.

Polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in particulates emitted by motorcycles

We determined eleven PAHs and four NPAHs in particulates and regulated pollutants (CO, CO2, HC, NOx, PM) exhausted from motorcycles to figure out the characteristics of motorcycle exhausts. Fluoranthene and pyrene accounted for more than 50% of the total detected PAHs. Among four detected NPAHs, 6-nitrochrysene and 7-nitrobenz[a]anthracene were the predominant NPAHs and were highly correlated relationship with their parent PAHs (R = 0.93 and 0.97, respectively). The PM and HC emissions tended to be close to the PAH emissions. NOx and NPAHs were negatively correlated. Despite their small engine size, motorcycles emitted much more PM and PAHs, showed stronger PAH-related carcinogenicity and indirect-acting mutagenicity, but weaker NPAH-related direct-acting mutagenic potency than automobiles. This is the first study to analyze both PAHs and NPAHs emitted by motorcycles, which could provide useful information to design the emission regulations and standards for motorcycles such as PM.

Determination of Selected Nitropolycyclic Aromatic Hydrocarbons in Water Samples

A new method for the analysis of selected nitropolycyclic aromatic hydrocarbons (NPAHs) at ultra-trace levels in water samples is proposed. Particulate NPAHs were collected on a GC glass fiber filter. Soluble NPAHs were collected on a C18 Empore disk. After simple clean-up and concentration of NPAHs in both phases, the NPAHs were analyzed using HPLC equipped with clean-up, reducer, concentration and chemiluminescence detection units. The proposed method showed good linear calibration curves with correlation coefficients (r(2)) ranging from 0.9954 to 0.9998. The limits of detection ranged from 0.013 to 0.15 nmol/L (soluble NPAHs) and from 0.01 to 0.13 nmol/L (particulate NPAHs) for 5 NPAHs [(9-nitroanthracene, 1-nitropyrene, 6-nitrochrysene (6-NC), 7-nitrobenz[a]anthracene and 6-nitrobenzo[a]pyrene] having 3 to 5 rings analyzed, when 1.5 L of water sample was used. The repeatability for soluble NPAHs ranged between 4.2 and 6.8% (n=5), while for particulate NPAHs, it varied between 2.2 and 2.8% (n=5). The proposed method successfully determined the above NPAHs expect 6-NC in river water samples, suggesting that this method is suitable for the ultra-trace analysis of NPAHs in water samples.

基于密度泛函理论的多环芳烃硝基衍生物的生物毒性预测

The optimum molecular geometry of 16 kinds of polycyclic aromatic hydrocarbons( PAHs) and six kinds of PAHs nitro derivatives were calculated by the B3LYP method of Density Functional Theory( DFT). Under the basis of 6-311 + + G( d,p),40 parameters of vibration frequency,polarizability,dipole moment and thermo-dynamical parameters were calculated. Using the toxicity of 13 PAHs for photobacterium as the dependent variable,other 3 PAHs were used to test and verify,toxicity of PAHs quantitative structure-activity relationship( QSAR) model based on quantum chemical parameters has been constructed to forecast the toxicity of PAHs nitro derivatives. The QSAR model has been proved that the model coefficient of simulation is 0. 816. The seriation of the toxicity of PAHs nitro derivatives calculated by the model is same with the toxicity sorting reported in the literature indicates that the model can be used to predict the toxicity of PAHs nitro derivatives. It also illustrated that there are similarities between the toxic mechanism of PAHs nitro derivatives and PAHs,so as to provide a theoretical basis for the control and prediction the toxicity of PAHs and PAHs nitro derivatives.

Spatial and temporal variations of nitro-polycyclic aromatic hydrocarbons in P2.5 aerosols in Yangtze River Delta Region, China

Nitrated polycyclic aromatic hydrocarbons (nitro-PAHs) are of great interest because of their high potential mutagenicity and carcinogenicity. PM2.5 aerosol campaigns were carried out for four seasons from December 2007 to January 2009 in Xujiahui, Baoshan and Lin’an in Yangtze River Delta Region, China. Nine nitro-PAHs were detected, the average seasonal concentrations for three sampling sites ranging between 0.17–879 pg m−3. 2-Nitrofluoranthene was the most abundant nitro-PAH, accounting for 54% of the total nitro-PAH concentration, followed by 9-nitroanthracene, 3-nitrophenanthrene and 7-nitrobenz(a)anthracene, about 15%, 16% and 10%, respectively. There were good correlation between mass concentrations of PM2.5 and the total concentrations of nitro-PAHs from samples in Xujiahui, R2 = 0.76, and Baoshan, R2 = 0.60; yet, a poor correlation in Lin’an, R2 = 0.44.

On the Primary Reaction Pathways in the Photochemistry of Nitro-Polycyclic Aromatic Hydrocarbons

The primary reaction pathways in the photochemistry of nitro-polycyclic aromatic hydrocarbons under specific laboratory conditions are briefly summarized. In addition, photochemical data is presented for 2-nitronaphthalene, 1-nitronaphthalene, and 2-methyl-1-nitronaphthalene in cyclohexane and acetonitrile solutions under aerobic and anaerobic conditions. It is shown that molecular oxygen significantly reduces the photodegradation quantum yield of 1-nitronaphthalene and 2-methyl-1-nitronaphthalene by 63% and 81%, respectively, whereas 2-nitronaphthalene is photoinert in both solvents under aerobic and anaerobic conditions. In addition, it is proposed that recombination of the aryl and nitrogen (IV) dioxide geminate radical pair within the solvent cage or internal conversion of an initially formed intramolecular charge transfer state may play an important role in the fraction of excited molecules that returns to the ground state in 1-nitronaphthalene and 2-methyl-1-nitronaphthalene. Scavenging of radical species by molecular oxygen and the generation of singlet oxygen in high yield are proposed to contribute to the photochemistry of these nitro-naphthalene derivatives in solution.

An Analytical Method to Determine Selected Nitro-PAHs in Soil Samples by HPLC With Fluorescence Detection

A simple analytical procedure was optimized for the analysis of selected nitro polycyclic aromatic hydrocarbons in soil samples. The procedure involved the sonication of analytes with dichloromethane and derivatization through sodium borohydride reduction. 3-Nitrophenanthrene, 9-Nitrophenanthrene, 1-Nitropyrene, and 3-Nitrofluoranthene were selected based on toxicity, abundance, and reference material availability. Analytical determinations were carried out by high-performance liquid chromatography with fluorescence detection, applying 254/410, 254/444, 244/438, and 244/528 nm for 3-Nitrophenanthrene, 9-Nitrophenanthrene, 1-Nitropyrene, and 3-Nitrofluoranthene detection, respectively. Quantification limits obtained for all of these compounds were between 16 and 60 ng kg−1 dry mass. Overall recoveries ranged from 89–106% at three fortification levels, and no significant bias was detected. Robustness of the method was demonstrated. Analyses over time were carried out for three types of soil samples and intermediate precision was estimated between 16 and 32%.

An evaluation of uncertainty associated to analytical measurements of selected polycyclic aromatic compounds in ambient air

This paper presents an evaluation of uncertainty associated to analytical measurement of 18 polycyclic aromatic compounds (PACs) in ambient air by liquid chromatography with fluorescence detection (HPLC/FD). The study was focused on analyses of PM10, PM2.5 and gas phase fractions. Main analytical uncertainty was estimated for 11 polycyclic aromatic hydrocarbons (PAHs), four nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) and two hydroxy-polycyclic aromatic hydrocarbons (OH-PAHs) based on the analytical determination, reference material analysis and extraction step. Main contributions reached 15–30% and came from extraction process of real ambient samples, being those for nitro-PAHs the highest (20–30%). Range and mean concentration of selected PACs measured in gas phase and PM10/PM2.5 particle fractions during a full year are also presented. Concentrations of OH-PAHs were about 2–4 orders of magnitude lower than their parent PAHs and comparable to those sparsely reported in literature.