Assessment of parent and alkyl -PAHs in surface sediments of Iranian mangroves on the northern coast of the Persian Gulf: Spatial accumulation distribution, influence factors, and ecotoxicological risks.

Spatial patterns, potential origins, and ecotoxicological risk of alkylated (APAH) -and parent -(PPAH) polycyclic aromatic hydrocarbons (PAHs) were studied in mangrove surface sediments along the northern coasts of the Persian Gulf, Iran. The mean total concentrations (ngg-1dw) ∑32PAH, ∑PPAHs and ∑APAHs in sediments were 3482 (1689-61228), 2642 (1109-4849), and 840 (478-1273), respectively. The spatial variability was similar among these PAH groups, with the highest levels occurring in Nayband National Marine Park (NNMP). Physicochemical environmental factors, such as sediment grain size, and total organic carbon (TOC) contents, are significant factors of PAH distribution. These findings suggest that PAH pollution level is moderate-to-high, supporting the current view that mangrove ecosystems are under intensive anthropogenic impacts, such as petrochemical, oil and gas loads, port activities, and urbanization. Non-parametric multidimensional scaling (NPMDS) ordination demonstrated that NNMP mangrove is the critical site exhibiting high loading of PAH pollutants. Here, for the first time in this region, Soil quality guidelines (SQGs), Toxic equivalency quotient (TEQ), Mutagenic equivalency quotient (MEQ), and composition indices comprising Mean maximum permissible concentration quotient (m-MPC-Q), and Mean effect range median quotient (m-ERM-Q) methods were used to have a comprehensive risk assessment for PAH compounds and confirmed medium-to-high ecological risks of PAHs in the study area, particularly in the western part of the Gulf, highlighting the industrial impacts on the environment.

Presence of polycyclic aromatic hydrocarbons and persistent organochlorine pollutants in human Milk: Evaluating their levels, association with Total antioxidant capacity, and risk assessment.

Breastfeeding provides numerous health benefits for both infants and mothers, promoting optimal growth and development while offering protection against various illnesses and diseases. This study investigated the levels of polychlorinated biphenyls (PCB), organochlorine pesticides (OCP) and polycyclic aromatic hydrocarbons (PAH) in human milk sampled in Zadar (Croatia). The primary objectives were twofold: firstly, to evaluate the individual impact of each compound on the total antioxidant capacity (TAC) value, and secondly, to assess associated health risks. Notably, this study presents pioneering and preliminary insights into PAH levels in Croatian human milk, contributing to the limited research on PAH in breast milk worldwide. PCB and OCP levels in Croatian human milk were found to be relatively lower compared to worldwide data. Conversely, PAH levels were comparatively higher, albeit with lower detection frequencies. A negative correlation was established between organic contaminant levels and antioxidative capacity, suggesting a potential link between higher antioxidative potential and lower organic contaminant levels. Diagnostic ratio pointed towards traffic emissions as the primary source of the detected PAH. The presence of PAH suggests potential health risk, underscoring the need for further in-depth investigation.

An extensive investigation on human risk associated with PAHs in fish and sediment in Bushehr, Northern of Persian Gulf.

Here, a comprehensive study was designed to estimate the human risk assessment attributed to exposure of polycyclic aromatic hydrocarbons (PAHs)in sediment and fish in most polluted shore area in north of Persian Gulf. To this end, a total of 20 sediment and inhabitual Fish, as one of most commercial fish, samples were randomly collected from 20 different stations along Bushehr Province coastline. The 16 different components of PAHs were extracted from sediment and edible parts of inhabitual fish and measured with high-performance liquid chromatography (HPLC) and gas chromatography (GC), respectively. In addition, dietary daily intake (DDI) values of PAHs via ingestion Indian halibut and the incremental lifetime cancer risk (ILCR) attributed to human exposure to sediments PAHs via (a) inhalation, (b) ingestion, and (c) dermal contact for two groups of ages: children (1-11 years) and adults (18-70 years) were estimated. The results indicated that all individual PAHs except for Benzo(b)flouranthene (BbF) and Benzo(ghi) perylene (BgP) were detected in different sediment sample throughout the study area with average concentration between 2.275 ± 4.993 mg.kg-1 dw. Furthermore, Naphthalene (Nap) with highest average concentration of 3.906 ± 3.039 mg.kg-1 dw was measured at the Indian halibut. In addition, the human risk analysis indicated that excess cancer risk (ECR) attributed to PAHs in sediment and fish in Asaluyeh with high industrial activities on oil and derivatives were higher the value recommended by USEPA (10-6). Therefore, a comprehensive analysis on spatial distribution and human risk assessment of PAHs in sediment and fish can improve the awareness on environmental threat in order to aid authorities and decision maker to find a sustainable solution.

Accumulation of Atmospheric PAHs in White Mustard - Can the Seeds Be Affected?

Traffic-related particulate matter emissions have been considerably reduced due to stringent regulations in Europe. However, emission of diesel-powered vehicles still poses a significant environmental threat, affecting rural ecosystems and agriculture. Several studies have reported that polycyclic aromatic hydrocarbons (PAHs), a group of potentially toxic organic compounds, can accumulate in crops and vegetables. In our study, white mustard (Sinapis alba L.) plants were experimentally treated with an extract of diesel exhaust. PAH concentrations were measured in the different plant compartments (stems, leaves and seeds), bioconcentration factors (BCFs) were also calculated. Significant accumulation was measured in the leaves and seeds, stems showed lower accumulation potential. All plant matrices showed high tendency to accumulate higher molecular weight PAHs, BCF was the highest in the 6-ring group. The fact that considerable accumulation was experienced in the seeds might show the risk of cultivating crops nearby roads highly impacted by traffic-related emissions.

MOF-derived porous carbon microspheres Ni@C-acid as solid-phase microextraction coating for extraction of polycyclic aromatic hydrocarbons from tea infusions.

The improvement of the stability and adsorption properties of materials on targets in sample pre-treatment has long been an objective. Extensive efforts have been made to achieve this goal. In this work, metal-organic framework Ni-MOF precursors were first synthesized by solvothermal method using polyvinylpyrrolidone (PVP) as an ideal templating agent, stabiliser and nanoparticle dispersant. After carbonization and acid washing, the nanoporous carbon microspheres material (Ni@C-acid) was obtained. Compared with the material without acid treatment (Ni@C), the specific surface area, pore volume, adsorption performance of Ni@C-acid were increased. Thanks to its excellent characteristics (high stability, abundant benzene rings), Ni@C-acid was used as fiber coatings in headspace solid-phase microextraction (HS-SPME) technology for extraction and preconcentration of polycyclic aromatic hydrocarbons (PAHs) prior to gas chromatography-flame ionization detector (GC-FID) analysis. The experimental parameters of extraction temperature, extraction time, agitation speed, desorption temperature, desorption time and sodium chloride (NaCl) concentration were studied. Under optimal experimental conditions, the wide linear range (0.01-30 ng mL-1), the good correlation coefficient (0.9916-0.9984), the low detection limit (0.003-0.011 ng mL-1), and the high enrichment factor (5273-13793) were obtained. The established method was successfully used for the detection of trace PAHs in actual tea infusions samples and satisfied recoveries ranging from 80.94-118.62 % were achieved. The present work provides a simple method for the preparation of highly stable and adsorbable porous carbon microsphere materials with potential applications in the extraction of environmental pollutants.

Multispecies and multibiomarker assessment of fish health from Iguaçu River reservoir, Southern Brazil.

This study investigated the impact of micropollutants on fish health from Segredo hydroelectric reservoir (HRS) along the Iguaçu River, Southern Brazil, contaminated by urban, industrial, and agricultural activities. This is the first comprehensive study assessment in the river after the severe drought in the 2020s in three fish species from different trophic levels Astyanax spp. (water column depth/omnivorous), Hypostomus commersoni (demersal/herbivorous), and Pimelodus maculatus (demersal/omnivorous). Animals, water, and sediment samples were collected from three distinct sites within the reservoir: Floresta (upstream), Iratim (middle), and Station (downstream). The chemical analysis revealed elevated concentrations of metals (Al, Cu, Fe) and the metalloid As in water, or Cu, Zn, and As in sediment, surpassing Brazilian regulatory limits, while the organic pollutants as DDT, PAHs, PCBs, and PBDEs were found under the Brazilian regulatory limits. The metal bioaccumulation was higher in gills with no significant differences among sites. The species Astyanax spp. and H. commersoni displayed variations in hepatosomatic index (HSI) and P. maculatus in the condition factor index (K) between sites, while adverse effects due to micropollutants bioaccumulation were observed by biochemical, genotoxic, and histopathological biomarkers. The principal component analysis and integrated biomarker response highlighted the upstream site Floresta as particularly inhospitable for biota, with distinctions based on trophic level. Consequently, this multifaceted approach, encompassing both fish biomarkers and chemical analyses, furnishes valuable insights into the potential toxic repercussions of micropollutant exposure. These findings offer crucial data for guiding management and conservation endeavors in the Iguaçu River.

Search for new green natural solid phases for sample preparation for PAHs determination in seafood samples followed by LC and GC-MS/MS analysis.

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic organic pollutants found in various environments, notably aquatic ecosystems and the food chain, posing significant health risks. Traditional methods for detecting PAHs in food involve complex processes and considerable reagent usage, raising environmental concerns. This study explores eco-friendly approaches suing solid phases derived from natural sources in matrix solid phase dispersion. We aimed to develop, optimize, and validate a sample preparation technique for seafood, employing natural materials for PAH analysis. Ten natural phases were compared with a commercial reference phase. The methodology involved matrix solid phase dispersion and pressurized liquid extraction, followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Three solid phases (perlite, sweet manioc starch, and barley) showed superior performance in LC-MS/MS and were further evaluated with gas chromatography-tandem mass spectrometry (GC-MS/MS), confirming perlite as the most effective phase. Validation followed Brazilian regulatory guidelines and European Community Regulation 2021/808/EC. The resulting method offered advantages in cost-effectiveness, reduced environmental impact, cleaner extracts, and enhanced analytical performance compared to the reference solid phase and LC-MS/MS. Proficiency analysis confirmed method reliability, with over 50% alignment with green analytical chemistry principles. In conclusion, this study developed an environmentally sustainable sample preparation technique for seafood analysis using natural solid phases, particularly perlite, for PAH determination.

Distribution of 35 Polycyclic Aromatic Hydrocarbons in Pine Needle Samples from Selected Locations in the Republic of Korea.

Polycyclic aromatic hydrocarbons (PAHs), dust, and wax were measured in pine needles, and PAHs were also measured in surface soil. Pearson correlation analysis was performed between the analytical values. The main compounds responsible for the increase in total PAHs were non-carcinogenic phenanthrene and fluoranthene. Therefore, the % content of carcinogenic PAHs decreased with a slope = -0.037 (r = 0.47, p < 0.01), as the total PAH concentration in pine needles increased. Correlations between individual PAHs in pine needles and surface soil were very high when only low-number ring PAHs (2R- and 3R-PAHs) were statistically analyzed and significant when only high-number ring PAHs were statistically analyzed. Low-number ring PAH mainly moves in the gas phase and diffuses into the wax layer, so it was found to be statistically significant with the wax content of pine needles. High-number ring PAHs showed a high correlation with the amount of dust in pine needles because they mainly attached to dust particles and accumulated on the surface of pine needles. The ratios of fluoranthene/pyrene and methylphenanthrene/phenanthrene for predicting the origin of atmospheric PAHs have also been proven valid for pine needles.

Flexible filament winding strategy to prepare COF@polyionic liquid-coated fibers for non-selective exclusion of macromolecules in electro-enhanced solid-phase microextraction.

BACKGROUND: Accurate quantitative analysis of small molecule metabolites in biological samples is of great significance. Hydroxypolycyclic aromatic hydrocarbons (OH-PAHs) are metabolic derivatives of emerging pollutants, reflecting exposure to polycyclic aromatic hydrocarbons (PAHs). Macromolecules such as proteins and enzymes in biological samples will interfere with the accurate quantification of OH-PAHs, making direct analysis impossible, requiring a series of complex treatments such as enzymatic hydrolysis. Therefore, the development of matrix-compatible fiber coatings that can exclude macromolecules is of great significance to improve the ability of solid-phase microextraction (SPME) technology to selectively quantify small molecules in complex matrices and achieve rapid and direct analysis. RESULTS: We have developed an innovative coating with a stable macromolecular barrier using electrospinning and flexible filament winding (FW) technologies. This coating, referred to as the hollow fibrous covalent organic framework@polyionic liquid (F-COF@polyILs), demonstrates outstanding conductivity and stability. It accelerates the adsorption equilibrium time (25 min) for polar OH-PAHs through electrically enhanced solid-phase microextraction (EE-SPME) technology. Compared to the powder form, F-COF@polyILs coating displays effective non-selective large-size molecular sieving. Combining gas chromatography-tandem triple quadrupole mass spectrometry (GC-MS/MS), we have established a simple, efficient quantitative analysis method for OH-PAHs with a low detection limit (0.008-0.05 ng L-1), wide linear range (0.02-1000 ng L-1), and good repeatability (1.0%-7.3 %). Experimental results show that the coated fiber exhibits good resistance to matrix interference (2.5%-16.7 %) in complex biological matrices, and has been successfully used for OH-PAHs analysis in human urine and plasma. SIGNIFICANCE: FW technology realizes the transformation of the traditional powder form of COF in SPME coating to a uniform non-powder coating, giving its ability to exclude large molecules in complex biological matrices. A method for quantitatively detecting OH-PAHs in real biological samples was also developed. Therefore, the filament winding preparation method for F-COF@polyILs coated fibers, along with fibrous COFs' morphology control, has substantial implications for efficiently extracting target compounds from complex matrices.

Spatial distribution of polycyclic aromatic hydrocarbons in water and sediment in the Ganga River: source diagnostics and health risk assessment on dietary exposure through a common carp fish Labeo rohita.

We evaluated spatial distribution and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in water and sediments at four selected sites of the Ganga River. Also, we measured PAHs in muscle tissues of Rohu (Labeo rohita), the most common edible carp fish of the Ganga River and potential human health risk was addressed. Total concentration of PAHs (∑PAHs) in water was highest at Manika Site (1470.5 ng/L) followed by Knuj (630.0 ng/L) and lowest at Adpr (219.0 ng/L). A similar trend was observed for sediments with highest concentration of ∑PAHs at Manika (461.8 ng/g) and lowest at Adpr Site (94.59 ng/g). Among PAHs, phenanthrene (Phe) showed highest concentration in both water and sediment. Of the eight major carcinogenic contributors (∑PAH8C), Indeno (1,2,3-C,D) pyrene (InP) did appear the most dominant component accounting for 42% to this group at Manika Site. Isomer ratios indicated vehicular emission and biomass combustion as major sources of PAHs. The ∑PAHs concentrations in fish tissue ranged from 117.8 to 758.0 ng/g (fresh weight basis) where low molecular weight PAHs assumed predominance (above 80%). The risk level in fish tissues appeared highest at Manika Site and site-wise differences were statistically significant (p < 0.05). The ILCR (> 10-4) indicated carcinogenic risk in adults and children associated with BaP and DBahA at Manika Site and with BaP at Knuj Site. Overall, the concentrations exceeding permissible limit, carcinogenic potential and BaP equivalent all indicated carcinogenic risks associated with some individual PAHs. This merits attention because the Ganga River is a reservoir of fisheries.

Atmospheric polycyclic aromatic hydrocarbons in India: geographical distribution, sources and associated health risk-a review.

Atmospheric distribution of polycyclic aromatic hydrocarbons and associated human health risks have been studied in India. However, a comprehensive overview is not available in India, this review highlights the possible sources, and associated cancer risks in people living in different zones of India. Different databases were searched for the scientific literature on polycyclic aromatic hydrocarbons in ambient air in India. Database searches have revealed a total of 55 studies conducted at 139 locations in India in the last 14 years between 1996 and 2018. Based on varying climatic conditions in India, the available data was analysed and distributed with four zone including north, east, west/central and south zones. Comparatively higher concentrations were reported for locations in north zone, than east, west/central and south zones. The average concentrations of ∑PAHs is lower in east zone, and concentrations in north, west/central and south zones are higher by 1.67, 1.47, and 1.12 folds respectively than those in east zone. Certain molecular diagnostic ratios and correlation receptor models were used for identification of possible sources, which aided to the conclusion that both pyrogenic and petrogenic activities are the mixed sources of PAH emissions to the Indian environment. Benzo(a)pyrene toxicity equivalency for different zones is estimated and presented. Estimated Chronic daily intake (CDI) due to inhalation of PAHs and subsequently, cancer risk (CR) is found to be ranging from extremely low to low in various geographical zones of India.

Probing the occurrence, sources and cancer risk assessment of polycyclic aromatic hydrocarbons in PM2.5 in a humid metropolitan city in China.

Fifty-two consecutive PM2.5 samples from December 2021 to February 2022 (the whole winter) were collected in the center of Chongqing, a humid metropolitan city in China. These samples were analysed for the 16 USEPA priority polycyclic aromatic hydrocarbons (16 PAHs) to explore their composition and sources, and to assess their cancer risks to humans. The total concentrations of the 16 PAHs (ng m-3) ranged from 16.45 to 174.15, with an average of 59.35 ± 21.45. Positive matrix factorization (PMF) indicated that traffic emissions were the major source (42.4%), followed by coal combustion/industrial emission (31.3%) and petroleum leakage/evaporation (26.3%). The contribution from traffic emission to the 16 PAHs increased from 40.0% in the non-episode days to as high as 46.2% in the air quality episode during the sampling period. The population attributable fraction (PAF) indicates that when the unit relative risk (URR) is 4.49, the number of lung cancer cases per million individuals under PAH exposure is 27 for adults and 38 for seniors, respectively. It was 5 for adults and 7 for seniors, when the URR is 1.3. The average incremental lifetime cancer risk (ILCR) for children, adolescents, adults and seniors was 0.25 × 10-6, 0.23 × 10-6, 0.71 × 10-6, and 1.26 × 10-6, respectively. The results of these two models complemented each other well, and both implied acceptable PAH exposure levels. Individual genetic susceptibility and exposure time were identified as the most sensitive parameters. The selection and use of parameters in risk assessment should be further deepened in subsequent studies to enhance the reliability of the assessment results.

[Characteristics, Sources Apportionment, and Health Risks of PM2.5-bound PAHs and Their Derivatives Before and After Heating in Zibo City].

Atmospheric polycyclic aromatic hydrocarbons (PAHs) and their derivatives are a global problem that influences the environment and threatens human health. To investigate the characteristics, sources, and health risk assessment of PM2.5-bound PAHs and their derivatives, PM2.5 were collected at an urban site in Zibo from November 5 to December 26, 2020, and the concentrations of 16 conventional PAHs, nine NPAHs, and five OPAHs in PM2.5 were analyzed using gas chromatography-mass spectrometry. Source apportionment of PAHs and their derivatives was conducted using diagnostic ratios and a PMF model, and the health risks of PAHs and their derivatives to adult men and women were evaluated using the source-dependent incremental lifetime cancer risk (ILCR) model. The results showed that the average concentrations of ∑16pPAHs, ∑9NPAHs, and ∑5OPAHs in PM2.5 of Zibo City during the sampling period were (41.61 ± 13.40), (6.38 ± 5.70), and (53.20 ± 53.47) ng·m-3, respectively. The concentrations of the three PAHs increased significantly after heating, which were 1.31, 2.04, and 5.24 times larger than those before heating. During the sampling period, Chr, BaP, and BaA were the dominant components of pPAHs; 9N-Ant and 2N-Flt + 3N-Flt were the dominant components of NPAHs; and ATQ and BZO were the dominant components of OPAHs. Source apportionment results showed that motor vehicles were the main source of PAHs and their derivatives in PM2.5 before heating, whereas after heating, the main sources were the mixed source of coal and biomass combustion and secondary formation. The total BaP equivalent (TEQ) was 14.5 ng·m-3 during the sampling period, and the TEQ increased significantly after heating, which was approximately 1.2 times of that before heating. Assisted by the individual PAH source apportionment results, the ILCR of PM2.5-boundPAHs and NPAHs in Zibo City had a certain potential carcinogenic risk for adult males (1.06 × 10-5) and females (9.32 × 10-6). Among them, the health risks of PAHs from gasoline vehicles, diesel vehicles, and coal/biomass combustion were significantly higher than those from other emission sources.

Development of a novel DGT passive sampler for measuring polycyclic aromatic hydrocarbons in aquatic systems.

Polycyclic aromatic hydrocarbons (PAHs) are priority pollutants and need to be measured reliably in waters and other media, to understand their sources, fate, behaviour and to meet regulatory monitoring requirements. Conventional water sampling requires large water volumes, time-consuming pre-concentration and clean-up and is prone to analyte loss or contamination. Here, for the first time, we developed and validated a novel diffusive gradients in thin-films (DGT) passive sampler for PAHs. Based on the well-known DGT principles, the sampler pre-concentrates PAHs with typical deployment times of days/weeks, with minimal sample handling. For the first time, DGT holding devices made of metal and suitable for sampling hydrophobic organic compounds were designed and tested. They minimize sorption and sampling lag times. Following tests on different binding layer resins, a MIP-DGT was preferred - the first time applying MIP for PAHs. It samples PAHs independent of pH (3.9 -8.1), ionic strength (0.01 -0.5 M) and dissolved organic matter < 20 mg L-1, making it suitable for applications across a wide range of environments. Field trials in river water and wastewater demonstrated that DGT is a convenient and reliable tool for monitoring labile PAHs, readily achieving quantitative detection of environmental levels (sub-ng and ng/L range) when coupled with conventional GC-MS or HPLC. ENVIRONMENTAL IMPLICATIONS: PAHs are carcinogenic and genotoxic compounds. They are environmentally ubiquitous and must be monitored in waters and other media. This study successfully developed a new DGT passive sampler for reliable in situ time-integrated measurements of PAHs in waters at the ng/L level. This is the first time to use passive samplers for accurate measurements of hydrophobic organic contaminants in aquatic systems without calibration, a big step forward in monitoring PAHs. The application of this new sampler will enhance our understanding of the sources, fate, behavior and ecotoxicology of PAHs, enabling improved environmental risk assessment and management of these compounds.

Atmospheric occurrences and bioavailability health risk of PAHs and their derivatives surrounding a non-ferrous metal smelting plant.

Non-ferrous metal smelting emits large amounts of organic compounds into the atmosphere. Herein, 20 parent polycyclic aromatic hydrocarbons (PPAHs), 9 nitrated PAHs (NPAHs), 14 chlorinated PAHs (ClPAHs), and 6 alkylated PAHs (APAHs) in atmospheric samples from a typical non-ferrous metal smelting plant (NMSP) and residential areas were detected. In NMSP, benzo[a]pyrene, dibenz[a,h]anthracene, 6-nitrochrysene, 9-chlorofluorene, and 1-methylfluorene were the predominant compounds in the particulate phase, while phenanthrene constituted 57.3% in the gaseous phase. The concentration of PAHs in residential areas around NMSP was 1.8 times higher than that in the control area. Additionally, there was a significant negative correlation between the concentration and the distance from the NMSP. In terms of health risks, although the skin penetration coefficient of PM2.5 is smaller than that of the gaseous phase, dermal absorption of PM2.5 posed a greater threat to the population, the incremental lifetime cancer risk (ILCR) of NMSP was 1.8 × 10-4. After considering bioavailability, BILCR decreased by 1-2 orders of magnitude in different regions, and dermal absorption decreased more than inhalation intake. Nevertheless, the dermal absorption of PM2.5 in NMSP still presents a probable carcinogenic risk. This study provides a necessary reference for the subsequent control of NMSP contamination.

Associations of polycyclic aromatic hydrocarbons mixtures with cardiovascular diseases mortality and all-cause mortality and the mediation role of phenotypic ageing: A time-to-event analysis.

The associations of polycyclic aromatic hydrocarbons (PAHs) with cardiovascular diseases (CVDs) and all-cause mortality are unclear, especially the joint effects of PAHs exposure. Meanwhile, no studies have examined the effect of phenotypic ageing on the relationship between PAHs and mortality. Therefore, this study aimed to investigate the independent and joint associations between PAHs and CVDs, all-cause mortality, and assess whether phenotypic age acceleration (PhenoAgeAccel) mediate this relationship. We retrospectively collected data of 11,983 adults from the National Health and Nutrition Examination Survey database. Firstly, Cox proportional hazards regression and restricted cubic splines were applied to evaluate the independent association of single PAH on mortality. Further, time-dependent Probit extension of Bayesian Kernel Machine Regression and quantile-based g-computation models were conducted to test the joint effect of PAHs on mortality. Then, difference method was used to calculate the mediation proportion of PhenoAgeAccel in the association between PAHs and mortality. Our results revealed that joint exposure to PAHs showed positive association with CVDs and all-cause mortality. By controlling potential confounders, 1-Hydroxynapthalene (1-NAP) (HR = 1.24, P = 0.035) and 2-Hydroxyfluorene (2-FLU) (HR = 1.25, P < 0.001) showed positive association with CVDs mortality, and they were the top 2 predictors (weight: 0.82 for 1-NAP, 0.14 for 2-FLU) of CVDs mortality. 1-NAP (HR = 1.15, P < 0.001) and 2-FLU (HR = 1.13, P < 0.001) also showed positive association with all-cause mortality, and they were also the top 2 predictors of all-cause mortality (weight: 0.66 for 1-NAP, 0.34 for 2-FLU). PhenoAgeAccel mediated the relationship between 1-NAP, 2-FLU and CVDs, all-cause mortality, with a mediation proportion of 10.00 % to 24.90 % (P < 0.05). Specifically, the components of PhenoAgeAccel including C-reactive protein, lymphocyte percent, white blood cell count, red cell distribution width, and mean cell volume were the main contributors of mediation effects. Our study highlights the hazards of joint exposure of PAHs and the importance of phenotypic ageing on the relationship between PAHs and mortality.

Effects of polystyrene nano- and microplastics and of microplastics with sorbed polycyclic aromatic hydrocarbons in adult zebrafish.

The presence of nanoplastics (NPs) and microplastics (MPs) in the environment is recognised as a global-scale problem. Due to their hydrophobic nature and large specific surface, NPs and MPs can adsorb other contaminants, as polycyclic aromatic hydrocarbons (PAHs), and modulate their bioavailability and hazard. Adult zebrafish were exposed for 3 and 21 days to: (1) 0.07 mg/L NPs (50 nm), (2) 0.05 mg/L MPs (4.5 µm), (3) MPs with sorbed oil compounds of the water accommodated fraction (WAF) of a naphthenic crude oil (MPs-WAF), (4) MPs with sorbed benzo(a)pyrene (MPs-B(a)P), (5) 5 % WAF and (6) 21 µg/L B(a)P. Electrodense particles resembling NPs were seen in the intestine lumen close to microvilli. MPs were abundantly found in the intestine lumen, but not internalised into the tissues. After 21 days, NPs caused a significant downregulation of cat, and upregulation of gpx1a and sod1, while MPs upregulated cyp1a and increased the prevalence of liver vacuolisation. No histopathological alteration was observed in gills. In this study, contaminated MPs did not increase PAH levels in zebrafish but results highlight the potential differential impact of plastic particles depending on their size, making it necessary to urgently address the ecotoxicological impact of real environmental NPs and MPs.

AhR agonists screening and identification in indoor dust based on non-target chemical analysis by GC-Q-TOFMS and biological effect evaluation referring to ToxCast/Tox21 database.

Numerous studies reported the concentration of agonists of aryl hydrocarbon receptor (AhR) in indoor dust by target chemical analysis or the biological effects of activating the AhR by indoor extracts, but the major AhR agonists identification in indoor dust were rarely researched. In the present study, the indoor dust samples were collected for 7-ethoxyresorufin O-deethylase (EROD) assay and both non-targeted and targeted chemical analysis for AhR agonists by gas chromatography quadrupole time-of-flight mass spectrometry and gas chromatography-mass spectrometry analysis. Coupled with non-targeted analysis and toxicity Forecaster (ToxCast)/Tox21 database, 104 ToxCast chemicals were screened to be able to induce EROD response. The combination of targeted chemical analyses and biological effects evaluation indicated that PAHs, dibutyl phthalate (DBP) and Cypermethrin might be the important AhR-agonists in different indoor dust and mainly contributed in 1.84%-97.56 % (median: 26.62%) of total observed biological effects through comparing toxic equivalency quotient derived from chemical analysis with biological equivalences derived from bioassay. DBP and cypermethrin seldom reported in the analysis of AhR agonists should raise great concern. In addition, the present results in experiment of synthetic solution of 4 selected AhR-agonists pointed out that some unidentified AhR agonists existed in indoor dust.

Mechanism of soot and particulate matter formation during high temperature pyrolysis and gasification of waste derived from MSW.

This research investigates the formation mechanism of soot and particulate matter during the pyrolysis and gasification of waste derived from Municipal Solid Waste (MSW) in a laboratory scale drop tube furnace. Compared with CO2 gasification atmosphere, more ultrafine particles (PM0.2, aerodynamic diameter less than 0.2 µm) were generated in N2 atmosphere at 1200℃, which were mainly composed of polycyclic aromatic hydrocarbons (PAHs), graphitic carbonaceous soot and volatile alkali salts. High reaction temperatures promote the formation of hydrocarbon gaseous products and their conversion to PAHs, which ultimately leads to the formation of soot particles. The soot particles generated by waste derived from MSW pyrolysis and gasification both have high specific surface area and well-developed pore structure. Compared with pyrolysis, the soot generated by gasification of waste derived from MSW had smaller size and higher proportion of inorganic components. The higher pyrolysis temperature led to the collapse of the mesoporous structure of submicron particles, resulting in a decrease in total pore volume and an increase in specific surface area. Innovatively, this research provides an explanation for the effect of reaction temperature/ CO2 on the formation pathways and physicochemical properties of soot and fine particulate matter.

Metals and polycyclic aromatic hydrocarbons pollutants in industrial parks under valley landforms in Tibetan Plateau: Spatial pattern, ecological risk and interaction with soil microorganisms.

The spatial patterns of pollutants produced by industrial parks are affected by many factors, but the interactions among polycyclic aromatic hydrocarbons (PAHs), metals, and soil microorganisms in the valley landforms of the Tibetan Plateau are poorly understood. Thus, this study systematically investigated the distribution and pollution of metals and PAHs in soil around an industrial park in the typical valley landform of the Tibetan Plateau and analyzed and clarified the interaction among metals, PAHs, and microorganisms. The results were as follows: metal and PAH concentrations were affected by wind direction, especially WN-ES and S-N winds; Cd (2.86-54.64 mg·kg-1) had the highest soil concentrations of the metals screened, followed by variable concentrations of Cu, Pb, and Zn; the pollution levels of metals and PAHs in the S-N wind direction were lower than those in the WN-ES wind direction; the Cd content of Avena sativa in the agricultural soil around the factory exceeded its enrichment ability and food safety standards; the closer to the center of the park, the higher the ecological risk of PAHs; and the TEQ and MEQ values of the PAHs were consistent with their concentration distributions. The results of the soil microbial diversity and co-occurrence network in the dominant wind direction showed that metal and PAH pollution weakened the robustness of soil microbial communities. Additionally, the diversity and robustness of soil microbial communities at the S wind site were higher than those at the ES wind site, which might be attributed to the lower metal content of the former than the latter, which plays a negative role in the biodegradation of PAHs. The results of this study provide insights into the site selection, pollutant supervision, and environmental remediation of industrial parks in typical landforms.