Explore the vast range of titles available.

This study determined the PAH contamination variations in the subtidal surface sediment with oil fingerprinting in the Wu Yi San oil spill in Yeosu, Korea, in January 2014. The ∑16 PAHs and ∑alkyl PAHs were investigated in surface sediment and seawater 1 month after the oil spill for 1 year at 3-month intervals in the accident (St. A-F) and adjacent areas (St. 1-20). The averaged ∑16 PAHs and ∑alkyl PAH concentration in the five samplings were 42.2–171.7 ng/g and 211.5–221.8 ng/g, respectively. Comparing the PAH levels in St.E and St.17 indicated a decreased tendency, from 357.9 to 31.1 ng/g dw. in ∑16 PAHs, and from 1900.9 to 211.5 ng/g dw. in ∑alkyl PAHs. The PAHs were not statically correlated between surface sediment and seawater (p > 0.05), implying that the fate of PAHs was rapidly dispersed toward adjacent coasts and beaches. Pyrogenic origin was predominant in 16 PAHs, and petrogenic origin in alkylated PAHs. Notably, C2-D/C2-P and C3-D/C3-P ratios in the accident area during the first sampling were similar to accident oil, but the similarity was not shown in other samplings. Only the C2-naphthalene (St.A), C1-phenanthrene (St.A and St.B), and C2-phenanthrene (the entire accident area points) concentrations were higher than the ERL SQG.

Introduction. Signs of pulmonary veno-occlusive disease (PVOD) may be found in patients with pulmonary arterial hypertension (PAH), particularly in systemic sclerosis (SSc)¹. This association (PVOD/PAH) remains poorly characterized in SSc. We aimed to compare the clinical, echocardiographic and hemodynamic profile of patients with SSc-PAH with and without a concomitant diagnosis of PVOD, and their potential response to vasodilators. Materials and Methods. We retrospectively analyzed 23 patients with SSc-PAH diagnosed by right heart catheterization, followed at our center between 2017 and 2023. Data collected at diagnosis and after 12 months included clinical, laboratory, functional and imaging parameters. Multidisciplinary assessment allowed the identification of cases with clinical and radiological features suggestive of PVOD/PAH¹. Patients were divided into two groups (PVOD/PAH and non-PVOD/PAH) and data were compared at baseline and 12-month follow-up. Results. Twenty-three patients with SSc-PAH were enrolled in the study, of whom 6 (26%) had signs of PVOD/PAH. At PAH diagnosis, PVOD/PAH patients had higher values of mean pulmonary arterial pressure compared to non-PVOD/PAH (47.5±5.3 vs. 36.7±8.8 mmHg, p=0.011), but similar pulmonary vascular resistance. Age, sex, cardiovascular risk factors, SSc features, echo findings as well as cardiac biomarker values were similar between the two groups (Table 1). At follow-up, most PVOD/PAH patients (67%) were on monotherapy with endothelin receptor antagonists (ERA), and 33% on dual therapy (ERA + phosphodiesterase inhibitors). Only one case of pulmonary edema was recorded. In the non-PVOD/PAH group, most patients (53%) were on dual vasodilator therapy. On echocardiography, PVOD/PAH patients showed higher tricuspid regurgitation velocity (4.10±0.68 vs. 3.07±0.91 m/s; p=0.035) and worse right ventricular function (FAC 25.6±8.4% vs. 33.9±6.8%; p=0.046). Changes in NT-proBNP levels from baseline differed between groups (p=0.012), showing a trend toward increase in PVOD/PAH (p=0.076) and reduction in non-PVOD/PAH (p=0.069). At 12 months, 5 hospitalizations for heart failure in each group, and a total of 5 deaths (2 PVOD/PAH and 3 non-PVOD/PAH) were recorded, with similar event-free survival (p=0.101). Conclusions. PVOD is frequently associated with PAH in SSc and does not seem to be associated with specific SSc features. Vasodilators, at least on monotherapy, should be considered in PVOD/PAH, as they seem to be well tolerated. Nevertheless, at follow-up these patients exhibit unfavorable laboratory and echo profiles compared to those with SSc-PAH alone, highlighting the importance of early referral for lung transplantation.

The Sugen 5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension (PAH) demonstrates most of the distinguishing features of PAH in humans, including increased wall thickness and obstruction of the small pulmonary arteries along with plexiform lesion formation. Recently, significant advancement has been made describing the epidemiology, genomics, biochemistry, physiology, and pharmacology in Su/Hx challenge in rats. For example, there are differences in the overall reactivity to Su/Hx challenge in different rat strains and only female rats respond to estrogen treatments. These conditions are also encountered in human subjects with PAH. Also, there is a good translation in both the biochemical and metabolic pathways in the pulmonary vasculature and right heart between Su/Hx rats and humans, particularly during the transition from the adaptive to the nonadaptive phase of right heart failure. Noninvasive techniques such as echocardiography and magnetic resonance imaging have recently been used to evaluate the progression of the pulmonary vascular and cardiac hemodynamics, which are important parameters to monitor the efficacy of drug treatment over time. From a pharmacological perspective, most of the compounds approved clinically for the treatment of PAH are efficacious in Su/Hx rats. Several compounds that show efficacy in Su/Hx rats have advanced into phase II/phase III studies in humans with positive results. Results from these drug trials, if successful, will provide additional treatment options for patients with PAH and will also further validate the excellent translation that currently exists between Su/Hx rats and the human PAH condition.

Polycyclic aromatic hydrocarbon (PAH) derivatives, specifically azaarenes and nitrated and oxygenated PAHs, are emerging contaminants of concern due to their increased toxicity and persistence compared to the parent PAHs. Despite their toxicity, their simultaneous analysis in complex matrices, such as in fumes emitted from bituminous mixtures, remains challenging due to limitations of conventional analytical techniques. To address this, an advanced methodology was developed using Ultra-High-Performance Liquid Chromatography coupled with High-Resolution Mass Spectrometry (UHPLC-HRMS Orbitrap Eclipse) equipped with an APCI source for the simultaneous identification and quantification of 14 PAH derivatives. Chromatographic and ionization parameters were optimized to ensure maximum sensitivity and selectivity. Following ICH Q2(R2) guidelines, the method was validated, demonstrating excellent linearity (R2 > 0.99), high mass accuracy (≤5 ppm), strong precision (<15%), and excellent sensitivity. Limits of detection (LODs) ranged from 0.1 µg L−1 to 0.6 µg L−1 and limits of quantification (LOQs) ranged from 0.26 µg L−1 to 1.87 µg L−1. The validated method was successfully applied to emissions from asphalt pavement materials collected on quartz filters under controlled conditions, enabling the identification and quantification of all 14 targeted compounds. These results confirm the method’s robustness and suitability for trace-level analysis of PAH derivatives in complex environmental matrices.

The aim of this paper is the presentation of the current state-of-the-art about the determination of polycyclic aromatic hydrocarbons (PAHs) and their oxidized forms originating from Suspended Particulate Matter (SPM) samples. The influence of SPM on health is twofold. SPM, as composed of small particles, is dangerous for the respiratory system. Additionally, SPM is a carrier of many hazardous compounds, particularly PAHs. Recently, several researches focus on the derivatives of PAHs, particularly nitro-, oxy- and hydroxy-PAHs, which are more dangerous than the parent PAHs. Both gas and high-performance liquid chromatography with various detection techniques are used to analyze both PAHs and their oxidized forms. Due to the appearance of these compounds in the environment, at a very low level, an analyte concentration step has to be applied prior to analysis. If GC and HPLC techniques are chiefly used as analytical tools for these analyses, the spectrum of analyte concentration procedures is very broad. Many analyte concentration techniques are proposed: from classic liquid-solid extractions, including Soxhlet technique, pressurized liquid extraction (ASE) or microwave oven (MWE) and sonic supported extraction to SPE techniques applications. However, one should remember that PAH determination methods are tools for solving the main problem, i.e., the evaluation the health hazard connected to the presence of SPM in air. Thus, the main drawback of several papers found in this review, i.e., the lack of information concerning limit of detection (LOD) of these methods makes their applicability very limited.

Polycyclic Aromatic hydrocarbons (PAHs) are ubiquitous hydrocarbon compounds consisting of more than two benzene rings. Petrogenic, pyrogenic, and biological processes are frequently reported sources of PAHs in the environment. In order to achieve the goal of reviewing the level of PAHs in fruits, vegetables, and fish species, as well as their health implications for humans in Africa, we vigorously searched through various databases, including Scopus, Science Direct, Google Scholar, and PubMed, and identified, collated, and summarized 41 articles published in these subject areas. PAH pollution have been found to possess high levels of toxicity, mutagenicity, carcinogenicity, teratogenicity, and immunotoxicity towards different organisms. Thus, this review succinctly outlined the formation process, distribution, mechanisms of exposure, and health effects of PAHs on human beings. The highest PAHs obtained in Africa in these samples were 510,000 μg/kg, 36,290 μg/kg and 19,003 μg/kg for fish, Pumkin leaf vegetable, and papaya fruit samples, respectively. Health risk assessment reports extracted from the numerous investigations done revealed low to extremely high levels of risks associated with their consumption by children and adults. To enhance public health, it is crucial to minimize the intake of dietary PAH and adopt practical and efficient risk management measures to decrease PAH levels in food. This review was done in an attempt to contribute to achieving good health and a sustainable environment as outlined by the Sustainable Development Goal (SDG). The investigation revealed an urgent need for the regulation of PAHs in Africa and recommended further research on fruits and vegetables from experts from different countries in Africa. Graphical Abstract

The concentration of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere has been continually monitored since their toxicity became known, whereas nitro-PAHs (NPAHs) and oxy-PAHs (OPAHs), which are derivatives of PAHs by primary emissions or secondary formations in the atmosphere, have gained attention more recently. In this study, a method for the quantification of 18 NPAH and OPAH congeners in the atmosphere based on combined applications of gas chromatography coupled with chemical ionization mass spectrometry is presented. A high sensitivity and selectivity for the quantification of individual NPAH and OPAH congeners without sample preparations from the extract of aerosol samples were achieved using negative chemical ionization (NCI/MS) or positive chemical ionization tandem mass spectrometry (PCI-MS/MS). This analytical method was validated and applied to the aerosol samples collected from three regions in Northeast Asia—namely, Noto, Seoul, and Ulaanbaatar—from 15 December 2020 to 17 January 2021. The ranges of the method detection limits (MDLs) of the NPAHs and OPAHs for the analytical method were from 0.272 to 3.494 pg/m3 and 0.977 to 13.345 pg/m3, respectively. Among the three regions, Ulaanbaatar had the highest total mean concentration of NPAHs and OPAHs at 313.803 ± 176.349 ng/m3. The contribution of individual NPAHs and OPAHs in the total concentration differed according to the regional emission characteristics. As a result of the aerosol samples when the developed method was applied, the concentrations of NPAHs and OPAHs were quantified in the ranges of 0.016~3.659 ng/m3 and 0.002~201.704 ng/m3, respectively. It was concluded that the method could be utilized for the quantification of NPAHs and OPAHs over a wide concentration range.

Polycyclic aromatic hydrocarbons (PAHs) are worldwide pollutants produced mainly during incomplete combustion and pyrolysis of organic substances. PAH derivatives are components with hydrogen on the aromatic ring substituted by carbonyl-, nitro- and hydroxyl-functional groups (N-PAH, O-PAH or OH-PAH), or a group of heterocyclic PAHs containing one sulfur atom in place of a carbon atom in the aromatic ring. PAHs and their derivatives can be either introduced in the atmosphere directly in this form as primary pollutants, or formed by homogenous and heterogeneous oxidation reactions. During the last decades, interest on studying PAH derivatives has increased because derivatives may be more harmful than parent compounds. PAH derivatives have been detected in the atmospheric particulate matter in numerous cities worldwide. PAH derivatives enter living organisms by inhalation, oral ingestion and dermal contact. In vivo and in vitro experiments together with epidemiological studies have shown the toxic effects of PAH derivatives, notably for compounds present in airborne and diesel exhaust particles. Here we review the sources, the mechanisms of formation, the physicochemical properties, the analytical methods, and the toxicological effects of PAHs and their derivatives in airborne particulate matter.

PAH ring-hydroxylating dioxygenases (PAH-RHDα) gene, a useful biomarker for PAH-degrading bacteria, has been widely used to examine PAH-degrading bacterial community in different contaminated sites. However, the distribution of PAH-RHDα genes in oilfield soils and mangrove sediments and their relationship with environmental factors still remain largely unclear. In this study, gene-targeted metagenomics was first used to investigate the diversity of PAH-degrading bacterial communities in oilfield soils and mangrove sediments. The results showed that higher diversity of PAH-degrading bacteria in the studied samples was revealed by gene-targeted metagenomics than traditional clone library analysis. Pseudomonas , Burkholderia , Ralstonia , Polymorphum gilvum , Mycobacterium , Sciscionella marina , Rhodococcus , and potential new degraders were prevailed in the oilfield area. For mangrove sediments, novel PAH degraders and Mycobacterium were predominated. The spatial distribution of PAH-RHDα gene was dependent on geographical location and regulated by local environmental variables. PAH content played a key role in shaping PAH-degrading bacterial communities in the studied samples, which would enrich PAH-degrading bacterial population and decrease PAH-degrading bacterial diversity. This work brings a more comprehensive and some new insights into the distribution and biodegradation potential of PAH-degrading bacteria in soil and sediments ecosystems.

Abstract Polycyclic aromatic hydrocarbon (PAH) contamination in marine environments range from low-diffusive inputs to high loads. The influence of PAH concentration on the expression of functional genes [e.g. those encoding ring-hydroxylating dioxygenases (RHDs)] has been overlooked in PAH biodegradation studies. However, understanding marker-gene expression under different PAH loads can help to monitor and predict bioremediation efficiency. Here, we followed the expression (via RNA sequencing) of Cycloclasticus pugetii strain PS-1 in cell suspension experiments under different naphthalene (100 and 30 mg L−1) concentrations. We identified genes encoding previously uncharacterized RHD subunits, termed rhdPS1α and rhdPS1β, that were highly transcribed in response to naphthalene-degradation activity. Additionally, we identified six RHD subunit-encoding genes that responded to naphthalene exposure. By contrast, four RHD subunit genes were PAH-independently expressed and three other RHD subunit genes responded to naphthalene starvation. Cycloclasticus spp. could, therefore, use genetic redundancy in key PAH-degradation genes to react to varying PAH loads. This genetic redundancy may restrict the monitoring of environmental hydrocarbon-degradation activity using single-gene expression. For Cycloclasticus pugetii strain PS-1, however, the newly identified rhdPS1α and rhdPS1β genes might be potential target genes to monitor its environmental naphthalene-degradation activity. This paper investigates how PAH-degrading bacteria may respond to varying levels of contamination through gene expression analysis for the first and most relevant step in naphthalene degradation.