Search Results (237)

Ultrafine particles (UFPs) containing polycyclic aromatic hydrocarbons (PAHs) benzo[a]pyrene (BaP), are linked to pollution-induced health concerns, with skin being highly susceptible to contamination. Understanding the metabolic fate of these environmental pollutants in the skin is crucial. Moreover, traditional in vitro models often lack metabolic competency, while animal testing raises ethical concerns. This study introduces a novel approach combining stable isotope labeling (SIL) and liquid chromatography–high-resolution mass spectrometry (LC-HRMS) to investigate BaP metabolism. The physiologically relevant 3D reconstructed human epidermis (RHE) model was used. RHE models were exposed to BaP and deuterium-labeled BaP (BaP-d12). These analyses, followed by data analysis incorporating stable isotope filtering, revealed the presence of five distinct BaP phase I metabolites, including mono-hydroxylated, dihydroxylated, and quinone derivatives. This study demonstrates the power of coupling stable isotope labeling with LC-HRMS for the comprehensive characterization of BaP metabolic pathways in human skin. The identification of specific metabolites enhances our understanding of BaP detoxification mechanisms and their potential adverse effects. This analytical approach holds promise for investigating the metabolic fate of various other environmental pollutants. Full article

The present investigation provides a comparative six-month analysis of atmospheric pollution by polycyclic aromatic hydrocarbons (PAHs) in the urban region of Opole, Poland. The study employs dual monitoring methods: traditional quartz filter-based active air sampling and active moss biomonitoring using Pleurozium schreberi, Sphagnum fallax, and Dicranum polysetum mosses. The experimental campaign took place from August 2021 to February 2022, spanning the autumn and winter seasons. PAH concentrations were measured using gas chromatography–mass spectrometry (GC-MS) following methodical sample extraction protocols. Filters documented transient air changes in PAHs, particularly high-molecular-weight (HMW) components such as benzo[a]pyrene (BaP), which exhibited considerable increases during the colder months due to heightened heating activities and less dispersion. The size of particles deposited on the filters varied from 0.16 to 73.6 μm, with an average size of 0.71 μm. Mosses exhibited cumulative uptake trends, with D. polysetum showing the greatest bioaccumulation efficiency, particularly for low- and medium-molecular-weight PAHs, followed by P. schreberi and S. fallax. Meteorological indices, including sun radiation and air temperature, demonstrated significant negative relationships with PAH buildup in mosses. Diagnostic ratio analysis verified primarily pyrogenic sources (e.g., fossil fuel burning), although petrogenic contributions were detected in D. polysetum, indicating its increased sensitivity to evaporative emissions. The study shows that the integration of moss biomonitoring with traditional filter samples provides a strong, complementary framework for assessing air quality, particularly in fluctuating meteorological settings. The results advocate for the integration of moss-based methodologies into environmental monitoring initiatives and provide significant insights into contaminant dynamics influenced by seasonal and meteorological factors. Full article

Currently, the potential environmental concerns around the world for polycyclic aromatic hydrocarbon carcinogenic (PAHCs) contamination as carcinogenic compounds in industrial soils (automobile industry) are rising day by day. At present, the technology of treating contaminated soils using photocatalysts is commonly used; however, this study tested photolysis and photocatalysis through ultraviolet light (306 nm) due to its high treatment efficiency. FeCl₃ (0.3, 0.4 M) was used as an iron catalyst for each treatment in the presence of H₂O₂ (10%, 20%) as an oxidizing agent. The impact of light treatment on soils that contained various concentrations of PAHCs like naphthalene (NAP), chrysene (CRY), benzo(a) pyrene (BaP), indeno (1,2,3-cd) pyrene (IND) was investigated. The QuEChERS method was used to extract PAHCs, and a gas chromatograph mass spectrometer (GCMSMS) was used to determine concentration. The concentrations of PAHCs were measured for soils at intervals of every 2 h after exposure to ultraviolet rays. The results showed a decrease in PAHCs concentrations with increased exposure to UV irradiation, as the initial values were 26.8 ng/g (NAP), 97 ng/g (CRY), 9.1 ng/g (BaP) and 9.7 ng/g (IND), which decreased to 2.17 ng/g (NAP), 3.14 ng/g (CRY), 0.33 ng/g (BaP) and 0.46 ng/g (IND) at 20, 40, 30 and 40 h of UV exposure; moreover, with an increase in concentration of the catalyst (0.4 M FeCl₃ with 20% H₂O₂), NAP, CRY, BaP and IND became undetectable at 8, 26, 14 and 20 h, respectively. It was concluded that a significant effect of ultraviolet rays on the photolysis of PAHCs, along with Photovoltaic at 306 nm wavelength, was observed while using FeCl₃ (0.4 M) combined with H₂O₂ (20%) produced better results in a shorter time compared to FeCl₃ (0.3 M) with H₂O₂ (10%). Full article

Plants from the Brassicaceae family are characterized by their high content of glucosinolates (GSLs), whose hydrolysis products, isothiocyanates (ITC) or indole compounds, have been found to have anti-inflammatory, antioxidant and metabolic regulatory functions. In this work, we used a model of transformation using the MCF10A cell line, a non-tumorigenic breast fibrocystic disease cell line, treated with benzo(a)pyrene (B(a)P), a potent carcinogen known to induce the production of reactive oxygen species (ROS) and DNA damage. Broccoli sprout (BSE) or red cabbage aqueous (RCA) extracts were rich in ITC and indole compounds. Their use decreased B(a)P induced cellular proliferation and ROS production. in addition, RCA extract induced autophagy in MCF10A cells. Our results indicate a potential use of BSE or RCA for the prevention of carcinogen-induced transformation and of RCA as a method for autophagy, a tumor suppressor pathway, induction. Full article

DNA methylation holds promise for the early detection of tissue damage, making it crucial for identifying polycyclic aromatic hydrocarbon (PAH)-associated epigenetic biomarkers in childhood asthma. Sulforaphane (SFN), as a potential epigenetic modulator, can alleviate the adverse effects of environmental pollutants. This study quantified serum PAHs in 370 children via gas chromatography–mass spectrometry, assessed the methylation of target genes using bisulfite sequencing PCR (BSP), and performed mediation analysis to estimate the mediating effects of methylation levels between PAHs and childhood asthma. Murine models exposed to PAHs prenatally or postnatally, with offspring challenged with ovalbumin (OVA), were analyzed for lung DNA methylation. In vitro, HBE cells and HBSMCs treated with benzo(a)pyrene (BaP) and/or SFN were tested for inflammatory cytokines, methylation-related enzymes, and matrix metallopeptidase 9 (MMP9) modifications. The results showed total PAHs were associated with childhood asthma, with mediating effects of long interspersed nuclear element-1 (LINE-1) methylation. Prenatal PAH exposure enriched differentially methylated genes in the extracellular matrix (ECM)-receptor interaction pathway, while postnatal exposure enriched those in purine metabolism, and postnatal exposure also elevated Mmp9 expression via hypomethylation. BaP increased the expression of interferon gamma (IFN-γ), interleukin-4 (IL-4), interleukin-17A (IL-17A), transforming growth factor beta 1 (TGF-β), and ten-eleven translocation methylcytosine dioxygenases (TETs), and it upregulated MMP9 via enhancer hypomethylation and H3K27ac enrichment, while SFN reversed these effects by downregulating histone methyltransferase (HMT), leading to reduced H3K4me1 and subsequent H3K27ac depletion, thus suppressing MMP9 transcription. This study demonstrates that DNA methylation mediates PAH–childhood asthma associations, with distinct patterns in different exposure windows; MMP9 could serve as a crucial target for epigenetic modification during lung inflammation induced by PAH exposure, and SFN reverses PAH-induced epigenetic changes, aiding prevention strategies. Full article

Asphalt concrete (ascon) manufacturing facilities in South Korea are located near urban areas and emit various air pollutants, including polycyclic aromatic hydrocarbons (PAHs) such as benzo(a)pyrene (BaP), a Group 1 carcinogen. However, few measurement-based studies exist in Korea, and no domestic BaP emission factor has been established, making its effective management difficult. In this study, PAH concentrations emitted from stacks were measured using gas chromatography/mass spectrometry at 29 facilities located near densely populated areas. BaP was detected at all facilities, and emission factors were calculated based on the ascon materials and dryer fuel types. The calculated emission factors were found to be 31 to 6230 times higher than the AP-42 standards provided by the US Environmental Protection Agency. This discrepancy likely arises from differences between processes and fuel characteristics. Using the California Puff model, BaP concentrations in the near area were predicted, corresponding to as much as 30% of the US National Ambient Air Quality Standards. These findings indicate a potentially significant environmental health risk in nearby communities. The findings of this study can serve as foundational data for formulating policies and providing institutional support aimed at managing emissions from ascon manufacturing facilities in Korea. Full article

While the cause of preterm birth (PTB) (i.e., delivery before 37 weeks of gestation) is likely multifactorial, ambient exposure to environmental chemicals has been postulated to play a role in its etiology. Our prior studies of exposure to polycyclic aromatic hydrocarbons (PAHs) in pregnancy have shown an increased level of placental PAH-induced bulky DNA adducts with increasing levels of PAH exposures. In this investigation, we hypothesized that higher levels of placental PAHs would be associated with an increased risk of PTB. Using gas chromatography and mass spectrometry (GC-MS/MS), we measured levels of benzo(a)pyrene (BaP), benzo(b)fluoranthene (BbF) and dibenz(a,h)anthracene (DBA) from n = 323 subjects. We found higher levels of BbF in placentae collected from preterm compared with term deliveries (mean 100.3 vs. 84.14 ng/mL, p = 0.038). Placental BbF levels negatively correlated with gestational age at delivery (r_s = −0.171, p = 0.002) and placental DBA levels were higher in placentae from spontaneous PTBs compared to those that were medically indicated (mean 743.7 vs. 599.9 ng/mL, p = 0.049), suggesting a potentially causal role in spontaneous preterm birth. Lastly, we analyzed placental levels of each PAH in male (n = 164) and female (n = 159) gestations and found that levels of BaP are significantly higher in males (mean 204.4 vs. 169.9 ng/mL, p = 0.049). These studies show a potential causal role of PAH exposure in the etiology of spontaneous preterm birth. Full article

Microbial detoxification, as an environmentally friendly strategy, has been widely applied for benzo[a]pyrene (BaP) degradation. Within this approach, food-derived microbial strains offer unique advantages in safety, specificity, and sustainability for detoxifying food-borne BaP. In this study, we aimed to explore the potential of such strains in BaP degradation. Bacillus mojavensis TC-5, a strain that degrades BaP, was isolated from kefir grains. Surprisingly, 12 genes encoding dehydrogenases, synthases, and oxygenases, including betB, fabHB, qdoI, cdoA, and bioI, which are related to BaP degradation, were up-regulated by 2.01-fold to 4.52-fold in TC-5. Two potential degradation pathways were deduced. In pathway I, dioxygenase, betaine aldehyde dehydrogenase, and beta-ketoacyl-ACP synthase III FabHB act sequentially on BaP to form 4H-pyran-4-one,2,3-dihydro-3,5-dihydroxy-6-methyl via the phthalic acid pathway. In the presence of the cytochrome P450 enzyme, BaP progressively mediates ring cleavage via the anthracene pathway, eventually forming 3-methyl-5-propylnonane in pathway II. Notably, TC-5 achieved an impressive BaP removal efficiency of up to 63.94%, with a degradation efficiency of 32.89%. These results suggest that TC-5 has significant potential for application in addressing food-borne BaP contamination. Moreover, our findings expand the application possibilities of Xinjiang fermented milk products and add to the available green strategies for BaP degradation in food systems. Full article

Sparse borehole sampling at contaminated sites results in sparse and unevenly distributed data on soil pollutants. Traditional interpolation methods may obscure local variations in soil contamination when applied to such sparse data, thus reducing the interpolation accuracy. We propose an adaptive graph convolutional network with spatial autocorrelation (ASI-GCN) model to overcome this challenge. The ASI-GCN model effectively constrains pollutant concentration transfer while capturing subtle spatial variations, improving soil pollution characterization accuracy. We tested our model at a coking plant using 215 soil samples from 15 boreholes, evaluating its robustness with three pollutants of varying volatility: arsenic (As, non-volatile), benzo(a)pyrene (BaP, semi-volatile), and benzene (Ben, volatile). Leave-one-out cross-validation demonstrates that the ASI-GCN_RC_G model (ASI-GCN with residual connections) achieves the highest prediction accuracy. Specifically, the R for As, BaP, and Ben are 0.728, 0.825, and 0.781, respectively, outperforming traditional models by 58.8% (vs. IDW), 45.82% (vs. OK), and 53.78% (vs. IDW). Meanwhile, their RMSE drop by 36.56% (vs. Bayesian_K), 38.02% (vs. Bayesian_K), and 35.96% (vs. IDW), further confirming the model’s superior precision. Beyond accuracy, Monte Carlo uncertainty analysis reveals that most predicted areas exhibit low uncertainty, with only a few high-pollution hotspots exhibiting relatively high uncertainty. Further analysis revealed the significant influence of pollutant volatility on vertical migration patterns. Non-volatile As was primarily distributed in the fill and silty sand layers, and semi-volatile BaP concentrated in the silty sand layer. At the same time, volatile Ben was predominantly found in the clay and fine sand layers. By integrating spatial autocorrelation with deep graph representation, ASI-GCN redefines sparse data 3D mapping, offering a transformative tool for precise environmental governance and human health assessment. Full article

To date, few studies have been carried out on the influence of the mixing effects of soils and remediation agents on the remediation effects of benzo[a]pyrene (B[a]P) in contaminated soils. In this study, the mixing effects of soils and remediation agents and the degradation effects of B[a]P under different stirring conditions were investigated by combining stirring tests with discrete element method (DEM) simulation. The results from the stirring tests indicated that the mixing effects of two-stage (C_Drill) drill bits were better than first-stage one-line (A_Drill) and first-stage cruciform (B_Drill) drill bits. The mixing quality of C_Drill at the drilling/raising rates of 2, 2.5, 3, 4, and 7.5 cm/min were 42.13%, 43.20%, 43.98%, and 43.30%, respectively. In terms of the results from the B[a]P oxidation remediation tests, the contaminated soils mixed with C_Dril have better remediation effects for B[a]p than those mixed with A_Dril and B_Dril, since B[a]p in contaminated soils stirred and mixed using C_Drill could not be detected after oxidative degradation. The present study results have proved that the mixing effects of soils and remediation agents could significantly affect the remediation effects of contaminated soils with polycyclic aromatic hydrocarbons (PAHs). Full article

The study presents an analysis of the concentrations of polycyclic aromatic hydrocarbons (PAHs) and particulate matter with a diameter of less than 10 µm (PM₁₀) in the air across various locations, as well as their impact on human health. Research in this area was conducted at eight stations as part of the national environmental monitoring system run in Poland by the Chief Inspectorate for Environmental Protection. Daily measurement data of PM₁₀ and the concentrations of PAHs associated with these particles were analyzed for the period from January to December 2023. The results showed that pollutant concentrations in the atmosphere vary depending on location, season, and meteorological conditions. The highest concentrations were observed during the winter season, when the combustion of solid fuels increases, while the lowest concentrations were recorded in the summer. The total concentration of PAHs ranged from 0.35 to 34.50 ng/m³. The annual average concentration of PM₁₀ at the analyzed stations was 19.29 ± 3.01 µg/m³. Principal component analysis indicated that PAHs in the air primarily originate from emissions related to transportation, biomass combustion, and industry. Furthermore, the estimated health risk, considering the Incremental Lifetime Cancer Risk (ILCR) index, showed that the risk of cancer associated with inhaling PAHs by children and adults did not exceed the permissible limits. The main contributor to the total carcinogenic activity of the PAH mixture was benzo(b)fluorantene (BbF) (31.5%), followed by benzo(a)pyrene (BaP) (5.5%), indeno(1,2,3-cd)pyrene (IP) (18.2%), benzo(j)fluorantene (BjF) (12.9%), benzo(k)fluorantene (BkF) (8.5%), benzo(a)anthracene (BaA) (2.5%), and dibenzo(a,h)anthracene (DBahA) (1.0%). Full article

This study investigates the concentrations, health risks, and potential sources of heavy metal elements and polycyclic aromatic hydrocarbons (PAHs) in PM_1.1 particles in Zhuji, a major copper-processing city in China. The ratios of heavy metals (summer: 0.906; winter: 0.619) and PAHs (>0.750 in both seasons) in PM_1.1/PM_2.0 suggest significant accumulation in ultrafine particles. In winter, heavy metal concentrations in PM_1.1 reached up to 448 ng/m³, and PAH concentrations were 13.4 ng/m³—over ten times higher than in summer. Health risk assessments revealed that hazard index (HI) values exceeded 1.00 for five age groups (excluding infants) during winter, indicating chronic exposure risks. Incremental lifetime cancer risk (ILCR) values surpassed the upper acceptable limit (1.0 × 10⁻⁴) for four age groups, with Cr, As, Cd, and Pb as major contributors. PAH-related ILCRs were also elevated in winter, with benzo[a]pyrene (BaP) identified as the most potent carcinogen. Enrichment factor (EF) and principal component analysis (PCA) indicated that industrial activities and traffic emissions were the dominant anthropogenic sources of heavy metals. Diagnostic ratio analysis further showed that PAHs mainly originated from vehicle and coal combustion. These findings provide critical insights into pollution patterns in industrial cities and underscore the importance of targeted mitigation strategies. Full article

Polycyclic aromatic hydrocarbons (PAHs), prevalent aquatic contaminants, arise from burning fossil fuels, a major source of greenhouse gases driving global warming. PAHs and warmer temperatures individually exert diverse negative effects on aquatic organisms. However, the effects of PAH exposure and/or rising temperature remain largely unknown. Liver in vitro models, like the rainbow trout (Oncorhynchus mykiss) RTL-W1 liver cell line, have been employed to unravel PAH-exposure effects, primarily on cell viability and enzymatic activity. Here, monolayer-cultured (2D) RTL-W1 cells were used to assess the co-exposure effects of temperature (18 and 21 °C) and two PAHs, benzo[a]pyrene (B[a]P) and benzo[k]fluoranthene (B[k]F), at 10 and 100 nM. After a 72 h exposure, the cell density and viability were evaluated using the trypan blue and LDH assays. The mRNA levels of the detoxification-associated genes aryl hydrocarbon receptor (AhR), cytochrome P450 (CYP)1A, CYP3A27, glutathione S-transferase omega 1 (GSTO1), uridine diphosphate–glucuronosyltransferase (UGT), catalase (CAT), and multidrug resistance-associated protein 2 (MRP2) were measured by RT-qPCR. Temperature influenced cell viability and LDH leakage. Both PAHs reduced the cell density and upregulated the mRNA levels of AhR, CYP1A, CYP3A27, and UGT, while GSTO1 and MRP2 were only augmented after the higher B[k]F concentration. Temperature influenced CAT and UGT expression. There was no interaction between temperature and the PAHs. Overall, the results show that B[k]F has more effects on detoxification targets than B[a]P, whereas a temperature increase mildly affects gene expression. The RTL-W1 in 2D seems useful for unravelling not only the liver effects of PAH but also the impact of temperature stress. Full article

Biological degradation effectively removes benzo(a)pyrene (BaP) from contaminated soil; however, knowledge regarding the contributions of plant absorption, microbial degradation, and volatilization to BaP removal remains limited. In this study, the BaP removal pathway in contaminated soil was investigated. The structural evolution of the microbial community in contaminated soil was revealed using a comparative experimental study. BaP, as a representative of high-molecular-weight polycyclic aromatic hydrocarbons, was removed from freshly contaminated soil by microbial degradation, plant absorption, and volatilization in proportions of 20.955%, 12.771%, and 0.005%, respectively. The proportions of BaP removed by microbial degradation, plant absorption, and volatilization in aged contaminated soil were 29.471%, 16.453%, and 0.004%. Microbial degradation was the most responsible mechanism for BaP removal. Moreover, a higher number of BaP degrading bacteria occurred in the aged contaminated soil. At the genus level, Pseudomonas and Sphingomonas were detected in both types of soils, being the key bacterial species involved in BaP degradation. Full article

Benzo[a]pyrene is an important indicator of polycyclic aromatic hydrocarbons pollution that exhibits complex atmospheric dynamics influenced by meteorological factors and suspended particulate matter (SPM). Herein, the factors influencing B(a)P concentration were elucidated by analyzing the monthly environmental data for Kyoto, Japan, from 2001 to 2021 using an improved association rule algorithm. Results revealed that B(a)P concentrations were 1.3–3 times higher in cold seasons than in warm seasons and SPM concentrations were lower in cold seasons. The clustering performance was enhanced by optimizing the K-means method using the sum of squared error. The efficiency and reliability of the traditional Apriori algorithm were enhanced by restructuring its candidate itemset generation process, specifically by (1) generating C₂ exclusively from frequent itemset L₁ to avoid redundant database scans and (2) implementing the iterative pruning of nonfrequent subsets during L_k → C_k+1 transitions, adding the lift parameter, and eliminating invalid rules. Strong association rules revealed that B(a)P concentrations ≤ 0.185 ng/m³ were associated with specific meteorological conditions, including humidity ≤ 58%, wind speed ≥ 2 m/s, temperature ≥ 12.3 °C, and pressure ≤ 1009.2 hPa. Among these, changes in pressure had the most substantial impact on the confidence of the association rules, followed by humidity, wind speed, and temperature. Under the influence of high SPM concentrations, favorable meteorological conditions further accelerated pollutant dispersion. B(a)P concentration increased with increasing pressure, decreasing temperature, and decreasing wind speed. Principal component analysis confirmed the robustness and accuracy of our optimized association rule approach in quantifying complex, nonlinear relationships, while providing granular, interpretable insights beyond the traditional methods. Full article