Polycyclic Hydrocarbons Research Articles

Atmospheric Transport of Semivolatile Organic Contaminants across an Urban-Alpine Boundary.

Current understanding of atmospheric transport of semivolatile organic contaminants (SVOCs) in alpine areas is limited due to complex meteorology and topography. Salt Lake City, Utah borders protected wilderness areas in the Wasatch Mountains, exhibiting a useful model system in which an urban source of SVOCs, including polyaromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), is located directly adjacent to an alpine sink. Our objective was to investigate the impacts of topographical features on the transport and deposition of SVOCs across an urban-alpine boundary. To do so, we measured PAHs and PCBs in soils along a transect starting at the urban-mountain interface and extending into an alpine wilderness, crossing several prominent ridgelines. Concentrations of PAHs and PCBs in soils were heavily influenced by soil organic carbon content, air temperature, and proximity to the urban boundary. However, the role of source proximity was only revealed after normalizing concentrations in soil to organic carbon content and air temperature. Further, we present evidence of SVOC emission/deposition cycles driven by diurnal alpine winds that do not extend past topographical features. Our results illustrate the roles of multiple competing processes on SVOC transport in alpine systems and their importance at an urban-alpine boundary.

Emission Factors, Chemical Composition and Ecotoxicity of PM10 from Road Dust Resuspension in a Small Inland City

Road dust resuspension in urban environments can contribute to high human exposure to metal(loid)s, polycyclic aromatic hydrocarbons, and other potentially toxic organic compounds. However, for many regions, information on loadings, emission factors and chemical profiles is lacking to accurately apply emission inventories and source apportionment models. In the present study, PM10 samples were collected with an in situ road dust sampler from eleven representative streets of Bragança, an inland city of the Iberian Peninsula, and were analysed for organic and elemental carbon by a thermal-optical technique, elemental composition by ICP-MS and ICP-OES, and ecotoxicity by a luminescence inhibition bioassay with Allivibrio fischeri. A global emission factor of 5.36 ± 2.35 mg veh−1 km−1 was obtained but in suburban areas the values reached twice the average. Total carbon accounted for 14.9 ± 6.8% of the PM10 mass, while element oxides represented the largest share (28.6 ± 18.7%). Very high enrichments were found for typical traffic-related elements such as Cu, Zn, S, Pb and Ni. The geochemical index Igeo further confirmed that road dust of the study region is extremely contaminated by elements mainly originated from tyre and brake wear. Although the total non-carcinogenic and carcinogenic risks associated with metal exposure were found to be low for both children and adults, the bioluminescence inhibition assay showed (eco)toxic responses for all samples, indicating that road dust resuspension may pose a significant human health and ecological threat.

Decoding Adverse Effects of Organic Contaminants in the Aquatic Environment: A Meta-analysis of Species Sensitivity, Hazard Prediction, and Ecological Risk Assessment.

Aquatic organisms in the environment are frequently exposed to a variety of organic chemicals, while these biological species may show different sensitivities to different chemical groups present in the environment. This study evaluated species sensitivity, hazards, and risks of six classes of organic chemicals in the aquatic environment. None of the taxonomic groups were the most sensitive or tolerant to all chemicals, as one group sensitive to one class of chemicals might possess adaptations to other chemical groups. Polychlorinated biphenyls were generally the most toxic chemical group, followed by polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, and pharmaceuticals and personal care products, while per- and polyfluoroalkyl substances and phthalate esters were the less toxic chemical groups. The hazard of organic chemicals was closely related to their physicochemical properties, including hydrophobicity and molecular weight. It was shown that 20% of the evaluated chemicals exhibited medium or high ecological risks with the worst-case scenario in the Pearl River Estuary. This novel work represented a comprehensive comparison of chemical hazards and species sensitivity among different classes of organic chemicals, and the reported results herein have provided scientific evidence for ecological risk assessment and water quality management to protect aquatic ecosystems against organic chemicals.

The Impact of Fat Contents and Different Cooking Processes on the Potential Health Concerns of Polycyclic Aromatic Hydrocarbons in Chicken Doner Kebabs

This study investigated the effects of different fat contents and cooking techniques on the presence of PAHs in chicken doner kebabs, as well as the dietary exposure and potential health risks for the Turkish population. The methodology for the detection and quantification of 16 PAH compounds in chicken doner samples using high-performance liquid chromatography (HPLC-UV) was validated. The limit of detection (LOD), quantification (LOQ), recovery, and relative standard deviation (RSD) were found to be 0.44%–1.14%, 1.45%–3.56%, 63.12%–101.50%, and 0.14%–3.16%, respectively. Our findings revealed that, among the analyzed compounds, BaA was the most dominant PAH compound, and that the charcoal cooking technique resulted in the highest accumulation of both BaP and PAH4 concentrations in chicken doner kebabs. Additionally, a significant increase in PAH levels was observed in relation to higher fat content. Moreover, it was found that the estimated daily intake (EDI) of BaP and PAH4 was higher in charcoal-grilled, well-done, high-fat chicken doner samples. As a result, the fact that the Margin of Exposure (MOE) values calculated for chicken doner samples across the Turkish population are above 10,000 indicates a low level of concern.

Adjustable Regioselectivity for the Diels-Alder Reactions of Sulfolenodipyrrins upon Molecular Engineering on H-Bonds.

The Diels-Alder reactions of sulfolenodipyrrins prove to be an efficient way to construct aromatic ring-fused dipyrrins. However, adjustable annulation is still hard to achieve. To address this, molecular engineering on the H-bond has been employed. The α-position aryl group-modified sulfolenodipyrrins have been synthesized to react with various dienophiles in Diels-Alder reactions, affording the monoannulation products with different regioselectivity in good yields (45-76%). The remaining sulfolenopyrrole in monoadducts can undergo further fusion in the presence of dienophiles and TEMPO, giving the bisadducts with a lactam subunit in an appropriate yield. According to the crystal structures and theoretical calculations, the intramolecular H-bonds between the α-substituent and the nearby pyrrole confine the conjugation pathway of the dipyrrin core. With respect to the normal NH-sulfolenopyrrole, the imino-type one features low aromaticity, from which SO2 extrusion generates more stable dipyrrin-diene, achieving regioselectivity. In addition, aromatic ring fusion results in red-shifted absorption and emission spectra, and the annulation units regulate the emission intensity. This work shows the versatility of intramolecular H-bonds in regulating the reaction through confinement of the conjugation system.

From flames to lab: A robust non-destructive sampling method for evaluating PAH exposure in firefighters’ personal protection equipment

Polycyclic aromatic hydrocarbons (PAHs) are compounds with high carcinogenic potential, produced during incomplete combustion. Certain professions, such as firefighting, expose workers to significant levels of PAHs during their operations, making it essential to investigate sampling protocols to evaluate their exposure in the work environment.This study presents a non-destructive and cost-effective sampling method for monitoring PAHs in firefighters’ personal protective equipment (PPE) and intervention vehicles. Sampling was conducted using three isopropanol wipes per collection zone, with comprehensive validation trials ensuring the method’s effectivenes. The method was tested under both natural contamination and spiking scenarios, showing similar results in both protocols.Analysis of contaminated PPE revealed significant PAH contamination in specific zones, such as gloves, lower back sleeves, and knees, due to direct exposure to flames and smoke during firefighting, with the highest concentrations in the outer and moisture layers. The cleaning efficacy of PPE was also evaluated employing specific washing machines, showing substantial reductions in PAH levels of approximately 76%. Additionally, non-targeted analysis detected organophosphate flame retardants (OPFRs) and furans, suggesting broader utility for environmental monitoring. This comprehensive approach improves the accessibility of chemical exposure studies in high-risk professions, contributing to better protective measures and occupational health and safety.

Passive sampling of polycyclic aromatic hydrocarbons with low-density polyethylene: Equilibration limitations in aqueous suspensions

Polyethylene (PE) and other polymers are widely and successfully used as passive samplers for organic pollutants in the environment. This study provides high-resolution experimental data from batch shaking tests on the uptake, reversibility, and linear equilibrium partitioning of polycyclic aromatic hydrocarbons (PAHs) using two different PE sheets of 30 µm and 80 µm thickness. Kinetics for phenanthrene are well described by a mechanistic first-order model with mass transfer limited by an aqueous boundary layer (with a mean thickness of 170 µm). Equilibration in laboratory batch systems during uptake and desorption is very rapid with characteristic times of 1–2 h but this depends on the boundary condition, e.g., the ratio of PE mass to water volume. Therefore, equilibration of PE in other setups, e.g., in soil slurries or sediment suspensions, may take orders of magnitude longer because the boundary condition for PE changes from finite to infinite bath conditions (soil or sediment particles may keep the concentration in water almost constant). Solid precipitates for high molecular weight PAHs explain partition coefficients below expected values because of kinetic limitations in such a system. Nevertheless, passive sampling can be employed safely if such limitations are considered; furthermore, partition coefficients can be estimated accurately by empirical relationships (e.g., within 0.1 log unit) based on molecular weight, octanol/water partition coefficients, or subcooled liquid solubilities.

Research on the types and toxicity of VOCs released from solvent-based inks in high temperature environment

ABSTRACT During the utilization, blending, transportation, and storage, a significant amount of volatile organic compounds (VOCs) are released from inks, posing risks to both human health and the ecological environment. This study sought to identify the types and structures of VOCs released from four types of solvent-based inks (referred to as CAB, PVB, AKR, and Rs inks) in high-temperature settings and to assess the bioaccumulation factors, developmental toxicity, and acute toxicity of these released VOCs. The findings revealed that all tested inks released substantial amounts of VOCs in high-temperature environments. CAB and PVB inks released fewer types of VOCs with relatively smaller molecular weights, primarily with carboxylic acid groups and hydroxyl groups, while AKR and Rs inks released more types of VOCs with larger molecular weights, including polycyclic aromatic hydrocarbons. Toxicity analysis indicated that although the primary VOCs released from CAB and PVB ink displayed some developmental toxicity, their bioaccumulation factors were below 100. The principal VOCs from AKR ink did not exhibit developmental toxicity. Conversely, the predominant VOCs from Rs ink not only demonstrated developmental toxicity but also had bioaccumulation factors exceeding 100. Additionally, the VOCs released from CAB, PVB, and AKR inks exhibited stronger acute toxicity to luminescent bacteria, while those from Rs ink showed greater acute toxicity to fish. These results offer a scientific foundation for the safe usage of inks and environmental conservation.

Post-Extractivism and Bioeconomy: An Experimental Analysis of Combustion and Pyrolysis Processes as Alternatives to Add Value to Agro-Residues (Coffee Husks) Generated in Farmer Cooperatives of the Ecuadorian Amazon

A post-extractivist development model for communities in the Amazon that is not based on non-renewable resource extraction demands the study and demonstration, in the field, of alternative economic activities that add value to currently generated residual biomass. Following the principles of bioeconomy, this study presents an experimental analysis of a retort burner and a pilot-scale auger-type pyrolysis reactor used to convert coffee husks generated in a collection and post-harvesting center of a farmer’s cooperative into thermal energy and biochar, respectively. This study shows that coffee husks, whether used as feedstock for combustion or pyrolysis processes, can supply the thermal energy required by the post-harvesting processes. The combustion or pyrolysis of coffee husks avoids its accumulation and decomposition while replacing fossil fuels used in post-harvesting operations, reducing costs and making farmers independent of fossil fuel subsidies. Unlike combustion (11,029.4 mg/Nm3), the CO concentration in the flue gas during the pyrolysis process was 458.3 mg/Nm3, which is below the eco-design standard of 500 mg/Nm3. According to the European Biochar Certificate, carbon content (67.4 wt%) and H/Corg, O/Corg (0.6 and 0.1, respectively) are within the typical values of biochars used for soil amendment and carbon sequestration. Nonetheless, the concentration of polycyclic aromatic hydrocarbons must be assessed to fully regard this material as biochar. Finally, further studies are required to assess the ability of cooperatives to generate and trade carbon credits linked with the application of biochar in their cropping systems.

Machine Learning Models for Predicting Bioavailability of Traditional and Emerging Aromatic Contaminants in Plant Roots.

To predict the behavior of aromatic contaminants (ACs) in complex soil-plant systems, this study developed machine learning (ML) models to estimate the root concentration factor (RCF) of both traditional (e.g., polycyclic aromatic hydrocarbons, polychlorinated biphenyls) and emerging ACs (e.g., phthalate acid esters, aryl organophosphate esters). Four ML algorithms were employed, trained on a unified RCF dataset comprising 878 data points, covering 6 features of soil-plant cultivation systems and 98 molecular descriptors of 55 chemicals, including 29 emerging ACs. The gradient-boosted regression tree (GBRT) model demonstrated strong predictive performance, with a coefficient of determination (R2) of 0.75, a mean absolute error (MAE) of 0.11, and a root mean square error (RMSE) of 0.22, as validated by five-fold cross-validation. Multiple explanatory analyses highlighted the significance of soil organic matter (SOM), plant protein and lipid content, exposure time, and molecular descriptors related to electronegativity distribution pattern (GATS8e) and double-ring structure (fr_bicyclic). An increase in SOM was found to decrease the overall RCF, while other variables showed strong correlations within specific ranges. This GBRT model provides an important tool for assessing the environmental behaviors of ACs in soil-plant systems, thereby supporting further investigations into their ecological and human exposure risks.

Associations of co-exposure to polycyclic aromatic hydrocarbons and heavy metals with sex steroid hormones among children aged 6-19 years.

Introduction Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are endocrine-disrupting chemicals (EDCs) that may have a combined effect on sex hormone levels in children. This study investigated the correlations between co-exposure to PAHs and HMs and levels of sex steroid hormones in children. Methods We employed the data from the National Health and Nutrition Examination Survey (NHANES) from 2013 to 2016, including 1,167 participants aged 6-19 years. Sex hormone indicators include testosterone (TT), estradiol (E2), sex hormone-binding globulin (SHBG), free androgen index (FAI), and the TT/E2 ratio. Weighted multivariate linear regression, weighted quantile sum (WQS) regression, and Bayesian kernel machine regression (BKMR) were used to analyze the associations between co-exposure to PAHs and HMs and sex steroid hormone levels. Results Co-exposure to PAHs and HMs was associated with a 16.2% reduction [95%CI (-0.321, -0.004)] in SHBG level among prepubertal males and a 16% reduction [95%CI (-0.30, -0.03)] in E2 level among pubertal males by the weighted quantile sum (WQS) regression, and cadmium (Cd) and mercury (Hg) contributed the highest weight respectively. In the Bayesian kernel machine regression (BKMR) model, co-exposure to PAHs and HMs was positively associated with TT/ E2 in pubertal males and negatively correlated with FAI in pubertal females, and 1-hydroxypyrene (1-PYR) and Cd were the most important components respectively. Conclusions Co-exposure to PAHs and HMs was associated with sex hormone levels in children. These findings highlight the necessity for preventing the effects of these chemicals on sex hormones.

Personal exposure of women to PM2.5-bound PAH derivatives from cooking emissions in varied rural kitchen setups

The present study investigates the personal exposure of women to PM2.5 and associated chemical constituents such as Elemental Carbon, Organic Carbon and 63 Poly Aromatic Hydrocarbons (PAH) compounds in varied kitchen setups viz. Indoor kitchen without partition (IKWO); Indoor kitchen with partition (IKWP); Separate enclosed kitchen outside the home (SEKO); Open kitchen (OK); and Open kitchen under stairway (OK_S) of south India. The exposure to PM2.5 was found to be highest in OK_S followed by IKWP, SEKO, IKWO and OK with average concentrations of 8943.54 ± 699, 6117.80 ± 1732, 4257.85 ± 2215, 2118.07 ± 524 and 1505.89 ± 431 μg/m3, respectively. Similarly, OK_S had the greatest levels of PM2.5-bounded PAHs (∑PAH63, ∑PAH16, and BaP) due to their small size and poor ventilation. The lifetime Excess Cancer Risk (ECR) indicated the highest lifetime exposure risk per million population (400) in OK_S type of kitchens followed by IKWO (307), SEKO (151), IKWP (149), and then OK (7) using the relative potency factor (RPF) which includes nitro-PAHs as well as methyl-PAHs apart from PAHs with high molecular weight. Additionally, it was shown that the lifetime ECR of biomass fuel was six times greater than that of LPG. The current analysis recommends a complete transition to LPG and strictly avoiding open kitchens under the staircase. Thus, the findings of this study will provide valuable information to improve the quality of the indoor environment of rural houses in India.

Effects of single and combined urinary polycyclic aromatic hydrocarbon effects on lung function in the U.S. adult population

BackgroundThe impact of polycyclic aromatic hydrocarbons (PAHs) on lung function has garnered attention, but studies mostly focus on individual effect. This study investigates urinary PAH metabolites as biomarkers of exposure and assesses the relationships between single and combined exposures to nine urinary PAH metabolites and lung function in adults.MethodsData from 4040 adults in the 2007–2012 National Health and Nutrition Examination Survey (NHANES) were analyzed. Weighted generalized linear models estimated the effects of individual PAH metabolites on lung function. Additionally, weighted quantile sum (WQS) regression, quantile g-computation (qgcomp), and Bayesian kernel machine regression (BKMR) were employed to evaluate the combined impacts of multiple PAH metabolites.ResultsAnalyses of individual PAH metabolites revealed negative associations with lung function, excluding forced vital capacity (FVC). The WQS, qgcomp, and BKMR models consistently showed that exposure to multiple PAH metabolites was associated with lung function decrease. WQS indicated that 2-hydroxynaphthalene (2-NAP) was the largest contributor to the reductions in forced expiratory volume in 1 s (FEV1), FVC, peak expiratory flow (PEF), and forced expiratory flow from 25 to 75% of FVC (PEF25-75%). Additionally, 1-hydroxypyrene (1-PYR) was the primary PAH metabolite contributing to the decreases in FEV1/FVC and fractional exhaled nitric oxide (FeNO). The combined effect of urinary PAH metabolites did not affect FVC in the current smokers or FeNO in nonsmokers, but decreased FEV1/FVC in current smokers.ConclusionThis study strengthens the negative relationships between multiple PAH metabolites exposure and lung function in adults. Given the limitations of this study, including the lack of knowledge of other exposure pathways and the uncertainty of urinary metabolites, further research is necessary to explore the mechanisms underlying these associations and to address the limitations in exposure assessment.

Influence of Contaminants Mercury and PAHs on Somatic Indexes of the European Hake (Merluccius merluccius, L. 1758).

This research investigates the dynamics of contaminant exposure in European hake (Merluccius merluccius, L. 1758) from the Adriatic Sea (Central Mediterranean Sea) by examining the levels of total mercury (THg) and polycyclic aromatic hydrocarbons (PAHs) in the muscle fish tissues. The study explores the correlations between these pollutants and somatic indexes to identify the early warning signals of pollution and ecological effects. The levels of pollutants are influenced by season and sex. Lipids appear to have a minimal effect on the PAH levels, whereas they exhibit a positive correlation with mercury levels in the muscle. No significant relationships between the pollutants and condition indexes were observed, except for a positive correlation between THg and the gonadosomatic index, indicating a potential impact on the reproductive health of fish. In contrast, PAHs showed no meaningful correlation with condition indexes. Differences in contaminant accumulations and lipid levels between sexes reflect variations in metabolic activity, reproductive costs, and adaptive strategies to seasonal changes and energy demands. This study highlights the importance of long-term monitoring to improve pollution management, environmental conservation, and the protection of marine organisms' health.

Decoupling Sources of Anthropogenic Influences on Sediments of the Visovac Lake (Krka National Park, Croatia) Using Multiparametric Approach.

Historical changes of sediment characteristics and levels of inorganic and organic contaminants were studied in dated sediment cores from the Visovac Lake, situated in the Krka National Park, Croatia, to identify the main sources of anthropogenic pressures on this highly protected system. Depth distributions of lithogenic elements showed a steady decrease of terrigenous inputs due to the reduction in agricultural activities in the area, which was particularly pronounced during the 1991-1995 war in Croatia. Vertical and longitudinal distributions of Cd and Zn indicated that they are predominately of anthropogenic origin. The historical profiles of these toxic metals coincide well with the recorded production of metal industry in the upper reach of the Krka River with a sharp decrease reflecting the interruption by the war and slow recovery afterwards. By contrast, the recovery of the tourist industry in Krka NP after the war was accompanied by increasing contamination by elements characteristic of boat and car traffic (Sn, Cu, Pb) as well as oil pollution. The contamination with polycyclic aromatic hydrocarbons and polychlorinated biphenyls was only moderate. Although levels of metallic and organic contamination can be considered relatively low, the observed shift from industrial to tourism-related sources indicated that touristic activities should also be regarded as a possible threat for this vulnerable karst aquatic ecosystem.

Chrysene contribution to bronchial asthma: Activation of TRPA1 disrupts bronchial epithelial barrier via ERK pathway

BackgroundElevated polycyclic aromatic hydrocarbon (PAH) levels are associated with exacerbation of asthma. Chrysene is one of the most prevalent unsubstituted PAHs in the environment. Transient receptor potential ankyrin 1 (TRPA1) can be used as a chemoreceptor to detect inhaled stimuli and plays an important role in the occurrence and deterioration of asthma. Whether exposure to a high concentration of chrysene in the environment can activate TRPA1 and contribute to the development of asthma, potentially through the dysfunction of the bronchial epithelial barrier, remains unclear. MethodsA cell-based assay was performed to verify the downregulation of the expression of E-cadherin and tight junction (TJ) proteins by chrysene in bronchial epithelial cells to explore the role of chrysene-mediated TRPA1 activation in the regulation of TJ protein expression through the extracellular signal-regulated protein kinase (ERK) pathway. Animal tests were conducted to determine whether chrysene could enhance airway hyperresponsiveness (AHR) induced by house dust mites (HDMs) and disrupt barrier function, thereby contributing to asthma. ResultsThe cell-based assay revealed that chrysene could disrupt the function of the bronchial epithelial barrier and decrease the expression levels of E-cadherin, zonula occludens-1 (ZO-1), occludin, and claudin-5 through the ERK pathway. Chrysene induced airway epithelial barrier dysfunction primarily through TRPA1 instead of transient receptor potential vanilloid 1. TRPA1 knockdown was able to attenuate chrysene-induced downregulation of TJ protein expression and downregulate ERK activation (p-ERK). Compared with exposure to HDM alone, coexposure to chrysene and HDM resulted in an increased incidence of AHR, disruption of barrier function, and eosinophilic inflammatory responses in a mouse model of asthma. Coexposure to chrysene and HDM increased TRPA1 expression. The animal test verified that the TRPA1 inhibitor HC030031 could suppress chrysene and HDM-induced asthma in mice. ConclusionsOur findings showed that chrysene contributed to the breakdown of the function of the bronchial epithelial barrier through the TRPA1–ERK axis and therefore acted as an adjuvant to contribute to asthma.

Enhanced Remediation of Phenanthrene and Naphthalene by Corn-Bacterial Consortium in Contaminated Soil.

The persistent and hazardous nature of polycyclic aromatic hydrocarbons (PAHs) released into the soil has become a critical global concern, contributing to environmental pollution. In this study, the removal efficiency of phenanthrene and naphthalene degradation by complex flora or pure bacteria combined with corn and their effects on the growth of corn, pH, and the number of soil bacteria were investigated using a pot experiment. The results indicate that the corn remediation method (P) outperformed degrading bacteria remediation (B) for phenanthrene, yet the combination (PB) exhibited significantly higher removal efficiency. The degradation efficiency of PB methods increased over time, ranging from 58.40% to 75.13% after 30 days. Naphthalene removal showed a similar trend. Soil pH, influenced by remediation methods, experienced slight but non-significant increases. The number of degrading bacteria increased with combined methods, notably with PB-W1 and PB-W2 treatments. Corn accumulated phenanthrene and naphthalene, with higher concentrations in roots. Remediation by the combined corn and degrading bacteria slightly increased PAH accumulation, indicating potential root protection. Biomass yield analysis revealed the inhibitory effects of PAHs on corn growth, decreased by degrading bacteria. PB-W1 and PB-EF3 demonstrated the highest fresh weight and moisture content for stem and leaf biomass, while PB-F2-6 excelled in root biomass. Overall, combined remediation methods proved more effective, which underscores the potential of the corn and degrading bacteria consortium for efficient PAH remediation in contaminated soil.

Benzo[b]fluoranthene damages coronary artery and affects atherosclerosis markers in mice and umbilical vein endothelial cells

Polycyclic aromatic hydrocarbons (PAHs) exposure is associated with cardiovascular diseases. Toxic effects of PAHs are diverse, while cardiovascular consequences of benzo[b]fluoranthene (B[b]F) are unclear. Here, we reported the impacts of B[b]F on coronary artery and atherosclerosis markers both in mice and umbilical vein endothelial EAhy.926 cells. In mice, we found that B[b]F decreases heart-to-body weight ratio, affects aortic physiology, elevates serum low-density lipoprotein and total cholesterol, increases aortic levels of collagen fiber and atherosclerotic marker vascular cell adhesion molecule-1 (VCAM-1), and downregulates oxidative stress related nuclear factor erythroid 2-related factor 2 (Nrf2). In EAhy.926 cells, we showed that B[b]F inhibits cell proliferation and migration in a dose-dependent manner, induces cell cycle arrest and apoptosis, increases reactive oxygen species, upregulates VCAM-1 level, and suppresses expression of Nrf2. Taken together, our findings reveal that B[b]F exposure may contribute to coronary artery damage and potentially induce atherosclerosis, possibly via the Nrf2-related signaling pathways.

Chemical speciation and oxidative potential of PM10 in different residential microenvironments: Bedroom, living room and kitchen

Exposure to particulate matter (PM) and its chemical constituents in residential microenvironments has become a major health concern worldwide. The oxidative potential (OP) has been proposed as a metric for estimating the PM capacity to induce oxidative stress and, consequently, health effects. In the present study, PM10 was daily monitored simultaneously in the bedroom, living room and kitchen of three dwellings for one week in a small town of Portugal, to perform a detailed characterisation of its organic and inorganic constituents and the determination of the OP. Bedrooms (B) were found to be a hotspot of PM10 concentrations (B1 = 22.7 μg m−3; B2 = 19.5 μg m−3; B3 = 68.1 μg m−3). PM10-bound elements varied significantly between microenvironments in all dwellings. Lower molecular weight polycyclic aromatic hydrocarbons (PAHs) were found to be between 14 and 72 times higher than high molecular weight PAHs in bedrooms. The mean volume-normalised OP determined by the dithiothreitol and ascorbic acid assays varied within the 0.01–0.38 nmol min−1 m−3 and 0.03–0.53 nmol min−1 m−3 ranges, respectively. Quinones, oxy-aromatic, aromatic and alkyl-aromatic compounds stood out in bedrooms. Strong and significantly positive relationship between OP and black carbon, Cu and Br were observed, indicating common redox active species mainly associated with traffic emissions. Sr, Fe, Zn and Zr presented higher concentrations in dwelling 3, exhibiting excellent positive correlation with OP, indicating that the Sahara dust intrusion recorded in that house may have contributed to the formation of more redox active species thought to drive antioxidant depletion responses.

Removal and mechanism investigation of polycyclic aromatic hydrocarbons in coconut oils by ionic liquids

Removal and mechanism investigation of polycyclic aromatic hydrocarbons in coconut oils by ionic liquids