Occurrence Of Polycyclic Aromatic Hydrocarbons Research Articles

Occurrence of Polycyclic Aromatic Hydrocarbons and Polychlorinated Biphenyls in Fogwater at Urban, Suburban, and Rural Sites in Northeast France between 2015 and 2021

Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) exist in the atmosphere in the vapor and particulate phases, as well as in solubilized form in fog/rain/cloud waters. In the current paper, fogwater samples are collected during 42 events between 2015 and 2021 at four different sites (Strasbourg, Geispolsheim, Erstein, Cronenbourg) in the Alsace region. Organics are extracted using liquid–liquid extraction (LLE) supported on a solid cartridge (XTR Chromabond), and then analyzed by gas chromatography–tandem mass spectrometry (GC-MS/MS). The total PAHs and PCBs concentrations in fog samples vary between 0.58 and 6.7 µg L−1 (average of 2.70 µg L−1), and 0.14 and 15.5 µg L−1 (average of 2.75 µg L−1). Low-molecular-weight (LMW) PAHs are predominant and highly detectable compared to high-molecular-weight (HMW) PAHs, while pentachloro-biphenyls are the dominant PCB congener. The PAHs and PCBs concentrations have increased over the sampling years at all sites, except for a slight decrease in PCBs level at Geispolsheim. A diagnostic ratio (DR) and principal component analysis (PCA) are applied to suggest potential contamination sources at Strasbourg metropolitan. Their results reveal that PAHs derive from a mixture of pyrogenic activities, while PCBs mainly come from industrial activities. The results also reveal, in some cases, inter-site variability for simultaneous and successive fog events.

Air‐Sea Gas Exchange and Its Potential Influence on the Regional Fate of Polycyclic Aromatic Hydrocarbons in the East China Marginal Sea

AbstractTo investigate the air‐sea gas exchange and its potential influence on the regional fate of polycyclic aromatic hydrocarbons (PAHs) in the East China Marginal Seas (ECMS), which consist of the East China Sea (ECS) and Yellow Sea (YS), we collected air and surface seawater samples of this area in the summer 2018 and winter 2019, respectively. Generally, PAHs underwent a strong volatilization process in the ECMS in both summer and winter. Good correlations between wind speed and the magnitude of air‐sea gas exchange were found for low molecular weight PAHs, suggesting the rate of their air‐sea gas exchange was influenced by the static stability of overlying atmosphere. However, such an influence for high molecular weight PAHs was constrained by their low Henry's law constant. Dissolved concentration of PAHs in surface seawater was another key factor regulating their air‐sea gas exchange, which not only influenced the rate of air‐sea gas exchange but also was involved in the exchange direction. Higher air‐sea gas exchange fluxes of PAHs in winter were attributed to their increasing dissolved concentrations in seawater during this season. A mass conservation analysis revealed a huge volatilization loss of PAHs from seawater to atmosphere, suggesting air‐sea gas exchange might be a key process to modulate the distribution and occurrence of PAHs in the ECS and YS. Such a loss of PAHs in seawater might be compensated by the sediment resuspension, which implied that the sedimentary deposit could serve as a secondary source of PAHs in seawater and overlying atmosphere.

The Occurrence of Polycyclic Aromatic Hydrocarbons in Fish Meat and Their Impact on Food Quality

Polycyclic Aromatic Hydrocarbons (PAHs) are organic compounds known to be potentially toxic for human health. Humans are exposed mostly through ingestion, but also through inhalation and skin contact. Thus, their concentrations in foods should be as low as possible. Fish products are appreciated as functional food, with high nutritional properties and organoleptic attributes. Despite these qualities, fish products may also contain PAHs. Humans are exposed to PAHs by eating fish meat, which can be contaminated from environmental sources, from industrial food processing methods, and from some home cooking practices. The main aspects concerning PAHs contamination of fish meat are briefly discussed: analysis and occurrence in some fish products, main factors and sources of contaminations, methodology of the determination of PAHs and current legislation on PAHs. The contamination of fish meat with PAHs has an impact on food quality. Mainly, topical studies from the last 20 years were taken into account, and also some studies that were the basis of the research in PAHs. The following platforms were used in the search: Web of Science and Scopus.

Association between PAH and plastic fragments on Brazilian coast beaches: a baseline assessment.

Plastic materials have many destinies on the environment, and one of them is its continuous fragmentation, originating microplastics (MP). MP act as an adsorption surface for organic pollutants like polycyclic aromatic hydrocarbons (PAH). Due to its toxic and harmful properties, 16 PAH are defined as priorities in studies. Several works have evaluated the occurrence of MP and PAH individually in environmental matrices, but just a few have investigated their association. The present study aims to investigate PAH occurrence, sources, and concentration in MP from beach sediments of eight Brazilian coastal states. Sixteen PAH were analyzed by gas chromatography, in which 14 PAH were detected, and PAH total concentration (ΣPAH) ranged from 0.25 to 71.60ngg-1. In the North and Northeast regions, the low PAH concentrations in MP appear to be related to the intense hydrodynamic processes. Naphthalene levels on the Styrofoam were above the threshold effect level in two samples and near it on one; therefore, effects in the organisms might occur due to these PAH. The Southeast and South regions are the only ones with previous studies relating PAH with MP, and ΣPAH ranged from 0.34 to 2.52ngg-1. According to the diagnostic ratios, the PAH sources were associated with industrial and port activities, untreated effluent disposal, and urban runoff by pluvial waters. The highest ΣPAH level was found in the Styrofoam samples, suggesting that this MP type might contribute considerable to PAH dispersion on Brazilian coast beaches.

Synchronous fluorescence spectra-based machine learning algorithm with quick and easy accessibility for simultaneous quantification of polycyclic aromatic hydrocarbons in edible oils

Polycyclic aromatic hydrocarbons (PAHs) are one of the leading causes of human cancer. Four typical PAHs (PAH4) including benzo(a)pyrene (BaP), benzo(b)fluoranthene (BbF), benzo(a)anthracene (BaA), and chrysene (Chr) have been regarded as reasonable indicators for the occurrence of PAHs in food. In this study, the constant wavelength synchronous fluorescence (CWSF) spectra of PAH4 mixtures were used as the data sets without preprocessing and directly combined with the back propagation neural network (BPNN) algorithm to establish a quantitative analysis method of PAH4. This method is capable of predicting the concentrations of PAH4 in edible oil samples without pre-separation. The detection limits for BaP, BbF, BaA, and Chr were 0.014, 0.068, 0.026, and 0.013 μg/kg, respectively. The recoveries in various oil samples for BaP, BbF, BaA, and Chr were 99.5 ± 2.1, 101.0 ± 4.6, 98.6 ± 3.2, and 98.5 ± 4.9 %, respectively. The proposed method has proved to be a powerful tool for the rapid detection of PAH4.

Polycyclic aromatic hydrocarbons (PAHs) in surface sediments from Greece: Occurrence, sources and risk assessment

This study examines the occurrence of Polycyclic aromatic hydrocarbons (PAHs) in sediment samples collected from three areas (Saronikos Gulf, Piraeus harbor, Heraklion) across the Hellenic coastline, while PAHs distribution, sources and ecotoxicological risk are evaluated. According to the detected concentrations of PAHs, the most contaminated area was Piraeus (ΣPAHs: 125 to 2720 ng/g dw), followed by Saronikos Gulf (ΣPAHs: 21.4–1820 ng/g dw) and Heraklion (4.10–230 ng/g dw). Most sampling sites clearly show evidence for “combustion” in the source, whereas the data from Piraeus harbor indicate petroleum contamination as well. The calculated Toxic Equivalence Quotient (TEQ) and Mutagenic Equivalence Quotient (MEQ) values for Saronikos Gulf and Heraklion reveal low, or no, adverse health effects to exposed biota, while the pollution picture in Piraeus port indicates that BaP is the main contributor to carcinogenic and mutagenic risk. Risk assessment regarding dermal uptake of PAHs corroborated a negligible risk.

Levels and risk assessment of polycyclic aromatic hydrocarbons, acrylamide and 5-hydroxymethylfurfural in yerba mate and its infusions

The occurrence and the risk of exposure to acrylamide (AA), 5-hydroxymethylfurfural (HMF) and polycyclic aromatic hydrocarbons (PAHs) in yerba mate leaves and infusions have been evaluated. The AA and HMF content have been examined for the first time, as most articles have focused only on PAHs occurrence or pro-healthy benefits of yerba mate. The results showed that acrylamide was detected in all samples, in the range 20–243 μg/kg, with the significantly lower amounts in the samples from Paraguay, and the highest from Argentina. HMF was found in 26 samples of 30, up to 466 mg/kg. The infusion transfers of acrylamide and HMF were higher than 21%, reaching even 77%. The total PAH amount in the leaves varied from 289 to 10643 μg/kg, and ƩPAH4 13-1871 μg/kg. The Brazilian samples contained significantly lower total PAH content than the Argentinian and Paraguayan samples. The transfer ratio from leaves to infusions was below 12 and 2.1% for total PAHs and PAH4. The results of multivariate method of analysis (Principal Component Analysis and Hierarchical Cluster Analysis) showed that yerba mate from Brazil and from Paraguay had their own specific features probably resulting from the method of thermal processing of the leaves. Finally, the calculated MOE values for all contaminants indicated a low level of concern for human health, which suggests that moderate consumption of yerba infusions should not pose a threat to human health.

Bacterial cell sensing and signaling pathway for external polycyclic aromatic hydrocarbons (PAHs)

The mechanism by which a bacterial cell senses external nutrients remains largely unknown. In this study, we identified a bacterial cell sensing system for polycyclic aromatic hydrocarbons (PAHs) in a common marine PAH-using bacterium, Cycloclasticus. It consists of an outer membrane receptor (PahS) and a periplasmic protein (PahP) in combination with a two-component sensing system (TCS) that ensures a rapid response to PAH occurrence by directly controlling serial reactions including chemotactic sensing and movement, PAH uptake and intracellular PAH metabolism. PahS protrudes from the cell and acts as a PAH sensor, transducing the PAH signal across the outer membrane to its periplasmic partner PahP, which in turn transduces the PAH signal across the periplasm to a specialized TCS. This sensing system plays a critical role in sensing and promoting the metabolism of PAHs, which can be scavenged by various hydrocarbon-degrading bacteria.

Black carbon, soil organic matter molecular signatures under different land uses in Shenyang, China and relationship with PAHs

The content, composition and molecular signatures of soil organic matter (SOM) have important influences on the cycle of soil organic carbon (SOC) and the partitioning of polycyclic aromatic hydrocarbons (PAHs) in soil. Seventy-nine soil samples from farmland, forest and urban areas were collected in Shenyang, China to investigate black carbon (BC) content, SOM molecular signatures varied with land use patterns, as well as the relationship with PAHs. The content of BC in urban soils was significantly higher than that of farmland and forest. BC was a key contributor of urban SOM which accounted for 0.35 ± 0.31 of SOC in urban soil. Based on BC/SOC ratio, the main sources of BC were identified as fossil fuel combustion for urban soils, while for farmland and forest soils, it is the mixed results of fossil fuel combustion and biomass burning. All categories of PAHs in urban soils showed the highest level compared to farmland and forest soils. Pearson's correlation analysis results showed there were significant positive correlations between BC and PAHs categories in urban soils, indicating the important role of BC in the accumulation of PAHs in soil. SOM from each of the two different land use patterns can be distinguished by molecular signatures. Urban SOM had abundant molecular markers derived from condensed organic carbon inputs, which was consistent with the BC/SOC value. Farmland SOM had abundant carbon from vegetation and microorganisms, and forest SOM was rich in organic carbon from fresh plant materials. The markers enriched in urban SOM showed significant correlations with most PAHs categories, highlighting the affinity of urban SOM for PAHs at the molecular level. This study contributed to understanding the impact of land management methods on SOM molecular composition signatures and its influence on PAHs occurrence in soil, providing a theoretical basis for regional soil pollution management.

Preliminary data on the occurrence of PAH and Anisakis spp. in Moroccan anchovies: Environmental parasitology and human health risk

This survey focuses on an environmental parasitology study by investigating Polycyclic Aromatic Hydrocarbons (PAH) bioaccumulation and the occurrence of Anisakis spp. on common anchovies collected from Moroccan coasts over 9 months through chemical (PAH) and Biological (Biometrics and parasitic) analysis. Obtained results were statistically analyzed and human health risks from anchovies consumption were assessed.The results obtained highlighted the good biological and chemical status of this fish in all stations of Morocco's coasts. Anisakis spp. was present in only four stations in the Atlantic fringe (maximum prevalence 22.22 %). Results have shown non-significant differences for tissue nature (Muscle, viscera) or spatial variation and were within a low range of concentrations well below the European Commission standards.Results have shown no serious harmful risk for humans from this fish consumption (ILCR and HI), and statistical analysis had shown positive correlations between prevalence and Chr, prevalence and sex-ratio, and prevalence and weight.

Polycyclic Aromatic Hydrocarbons in Air and Dust Samples from Vietnamese End-of-life Vehicle Processing Workshops: Contamination Status, Sources, and Exposure Risks.

Concentrations of 18 unsubstituted polycyclic aromatic hydrocarbons (PAHs) and 11 methylated derivatives (Me-PAHs) were measured in polyurethane foam-based passive air (PUF-PAS) and settled dust samples collected from end-of-life vehicle (ELV) processing workshops in northern Vietnam. Concentrations of total 29 PAHs ranged from 42 to 95 (median 57) ng/m3 and from 860 to 18,000 (median 5700) ng/g in air and dust samples, respectively. PAH levels in ELV air and dust samples were 1.5 ± 0.4 and 9.4 ± 7.9 times higher than levels found in a control house, suggesting ELV processing as potential PAH emission sources. Concentrations and proportions of Me-PAHs in total PAHs of the ELV air (26% ± 7%) and dust (41% ± 14%) were higher than those found in control house (18% in both air and dust). The occurrence of PAHs and Me-PAHs in the ELV workshops are attributed to not only pyrogenic but also petrogenic sources (i.e., improper treatment and management of fuels, lubricants, and vehicle oils).

Effect of Temperature Range and Kilning Time on the Occurrence of Polycyclic Aromatic Hydrocarbons in Malt.

Kilning is an integral part of malt production; it ensures grain and enzyme preservation. Kilning temperatures can range between 80 and 220 °C, depending on the type of malt that is being produced. Polycyclic aromatic hydrocarbons (PAHs) are prone to appear at higher temperatures and are generally designated as undesirable in food and beverages. Sixteen PAHs are framed in legislation, but there is a lack of scientific data related to PAHs in malt, malt-related foods (bread, cookies) and beverages (whisky, malted non-alcoholic beverages). The aim of this paper was to assess and quantify the occurrence of different PAHs in malts exposed to different kilning temperatures (50-210°) over a variable time frame. The results indicate that some of the PAHs detected at lower temperatures disappear when malt is exposed to high temperatures (>100 °C). Phenanthrene was no longer detected at 100 °C and indeno [1,2,3-cd] pyrene at 130 °C, while fluorene, anthracene and benzo (a) anthracene were not quantified at 170 °C. The results of this research can be implemented in food safety legislation since foods available to children utilize malted flour (bread, cookies, bakery goods, etc.) due to its enzymatic activity or as a colour additive.

Determination of Polycyclic Aromatic Hydrocarbons in Mate Tea Microencapsulated with Maltodextrin and Lasiodiplodan ((1→6) β–D-Glucan)

The occurrence of polycyclic aromatic hydrocarbons (PAH) in organic mate tea (Ilex paraguariensis) was investigated to evaluate whether the roasting and drying processes under milder temperatures would promote lower PAH levels in the product. Gas Chromatography with Flame Ionization Detector (GC-FID) was used to quantify PAH contents. Different concentrations of PAH were found in all samples of mate tea analyzed, such as acenaphthylene varied between 1.209 and 1.524 µg·g−1; acenaphthene varied between 2.504 and 4.375 µg·g−1; fluorene varied between 1.488 and 1.843 µg·g−1; chrysene ranged between 0.093 and 0.263 µg·g−1; benzo[a]pyrene varied between 0.988 and 3,398 µg·g−1; dibenzo(a,h) anthracene was identified in all the samples, but at concentrations below the limit of quantification. Naphthalene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene were identified in the sample used for the extraction of soluble solids that have been encapsulated. The PAH concentration in mate tea samples was above the recommended by European Union legislation for dried herbs and powders of food of plant origin for the preparation of beverages. New yerba mate processing strategies should be studied to minimize PAH contamination and promote healthier products, in addition to government policies for quality control and regulation specifying limit values for the PAHs.

Occurrence, sources, and spatial variation of POPs in a mountainous tropical drinking water supply basin by passive sampling

Persistent organic pollutants (POPs) are widely distributed along the world and their levels in surface waters may pose a risk to human health due to consumption of contaminated water or fish long-term exposure to contaminated water. The occurrence of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in the Piedras river (Colombia) is a problem of serious concern since freshwater is conducted to a drinking water supply system that provides more than 3 million users. In this research, we deployed silicone rubber membranes as passive samplers in two sampling campaigns at seven sampling stations selected along the river, to assess sources and spatial variation of POPs. The measurements confirmed freely dissolved concentration of the EPA prioritized PAHs (excluding naphthalene), PCBs, heptachlor isomers, dieldrin, endosulfan isomers, among other POPs at trace levels in the water source. The Risk Quotient (RQ) method was applied to prioritize POPs with the highest potential toxicity over aquatic ecosystems. The OCP Heptachlor overcome RQ, while Dieldrin and Endosulfan, and some PAHs congeners such as Perylene, Pyrene, Benzo[a]pyrene, and Fluoranthene displayed medium-risk RQ. Significant differences between sampling stations assessed by One-way ANOVA suggested that the main PAHs and PCBs sources to the river were the punctual discharge from the WWTP and a leachate discharge form a landfill located in the study area. Additionally, nonpoint sources of OCPs were identified. Our results showed that the origin of PAHs and PCBs are associated with urban activities, while the contribution of OCPs is related to the presence of legacy pesticides from past usage in agricultural activities in the basin.

Important But Overlooked Potential Risks of Substituted Polycyclic Aromatic Hydrocarbon: Looking Below the Tip of the Iceberg

Substituted polycyclic aromatic hydrocarbons (PAHs) are PAH derivatives in which substituents replace hydrogen atoms on the aromatic benzene ring, or N/S/O atoms replace carbon atoms in aromatic rings. Compared to unsubstituted PAHs, some substituted PAHs have higher pollution levels and more significant toxicity than their parent PAHs (p-PAHs), and the International Agency for Research on Cancer (IARC) lists them as possible human carcinogens, which harm human health but lack sufficient examination. This paper summarizes and discusses the environmental occurrence and distribution, toxicity, and impacts of substituted PAHs on human health and compares with the 16 representative priority-controlled PAHs (PAHs16). According to occurrence of PAHs in various environmental media, it is shown that the mean concentration of individual substituted PAH in the air is higher than that of individual PAH16. The mean concentration of individual substituted PAH in the soil varies widely among different countries, with a difference of 100,000 times between the lowest level (Italy) and the highest level (USA). The mean individual alkylated PAH (APAHs) and oxygenated PAH (OPAHs) are the most abundant in surface water and sediments. In the aspect of toxicity effects, some substituted PAHs have been proved to have similar or identical toxicity as PAHs16. We summarize existing problems and propose future priority research areas through the analysis of the occurrence and toxicity of substituted PAHs in the environment, which is important for further research and regulation of substituted PAHs.Graphical Abstract

SPATIO-TEMPORAL OCCURRENCE, SOURCES, AND HUMAN HEALTH RISK OF 16-POLYCYCLIC AROMATIC HYDROCARBONS IN ANTHROPOGENIC VECTORED SOILS

This study determined the spatiotemporal distribution, sources, and human health hazards of sixteen polycyclic aromatic hydrocarbons (PAHs) in land-use soils. PAHs were determined by a gas chromatography-mass spectrometer (GC-MS). Total PAHs concentrations ranged from 125.3 to 2587.16 µgkg-1 showing concentrations in the order of topsoil < subsoil and wet season > dry season. PAHs occurrence exceeded the DPR-EGAPSIN target and intervention value in 33.3% and 11% of the samples. This study established variable concentrations of HPAHs relative to LPAHs with a predominance of carcinogenic 5-ring PAHs. The highest concentrations of total PAHs were at Warri military checkpoint. The cancer risk for infants was higher than for adults, and permissible target values, thus signifying human on-spot exposure risk. The results established that the source of PAHs is pyrogenic and petrogenic low-temperature combustion of petroleum fractions and high-temperature combustion of wood, grass, biomass, diesel, and vehicular traffic particulate emissions. The results demonstrated considerable concentration variation and potential for ecological and human health exposure risks. The results show PAHs exposures risk in military checkpoints and related catchments elsewhere.

Occurrence of polycyclic aromatic hydrocarbons, microplastics and biofilms in Alqueva surface water at touristic spots

Freshwater pollution is a huge concern. A study aiming to evaluate physico-chemical characteristics, microbiota, occurrence of two groups of persistent environmental pollutants with similar chemical properties (polycyclic aromatic hydrocarbons- PAHs and microplastics - MPs) in Alqueva's surface water was performed during 2021. Water samples were collected at three spots related to touristic activities (two beaches and one marina) during the Winter, Spring, Summer and Autumn seasons. In addition, the presence of biofilms on plastic and natural materials (stone, wood/ vegetal materials) were assessed and compared.Water quality based on physicochemical parameters was acceptable with a low eutrophication level. PAHs concentration levels were lower than the standard limits established for surface waters by international organizations. However, carcinogenic compounds were detected in two sampling locations, which can pose a problem for aquatic ecosystems. PAHs profiles showed significant differences when comparing the dry seasons with the rainy seasons, with a higher number of different compounds detected in Spring. Low molecular weigh compounds, usually associated with the atmospheric deposition and petroleum contamination, were more prevalent.MPs were detected in all samples except one during the Winter season. The polymers detected were poly(methyl-2-methylpropenoate), polystyrene, polyethylene terephthalate, polyamide, polypropylene, styrene butadiene, polyvinyl chloride and low /high density polyethylene with the last being the most frequent. Biofilms were more often detected on plastics than on natural materials. In addition, biofilms detected on plastics were more complex with higher microbial diversity (e.g., bacteria, fungi/yeast and phytoplancton organisms) and richer in extrapolymeric material. Based on morphological analysis a good agreement between microbiota and microorganism present in the biofilms was found. Among microbiota were identified microorganisms previously linked to plastic and PAHs detoxification suggesting the need for further studies to evaluate the viability of using biofilms as part of a green bioremediation strategy to mitigate water pollution.

Occurrence of polycyclic aromatic hydrocarbons (PAHs) in the seafood from an important fishing area in the East China Sea and a comparison between seafood from different origins.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed in a variety of coastal marine seafood from the Wentai fishing area, which is in proximity to highly urbanized areas and provides a significant portion of the marine aquatic products in Eastern China. Specifically, total PAHs ranged from 320 to 2500ng/g d.w., whereas carcinogenic PAHs ranged from 21 to 92ng/g d.w. According to the source diagnosis, the PAHs in the seafood were generally from sources highly related to fossil fuel. Thus, it is necessary to control the unintentional use of fossil fuels and optimize the energy structure in the terrestrial area nearby. Moreover, the food chain structure and the environmental behavior of PAHs through the food chain, which are relevant to dietary risk, were assessed. The δ15N values fell in a narrow range, which indicates a relatively short food chain, which is due to overfishing in this area. Furthermore, in this shortened food chain, the trophic magnification factors (TMFs) ranged from 0.23 to 6.6, which were generally higher than those in more complex food chains. The cancer risk (ILCR) ranged from 2.2 × 10-8 to 2.2 × 10-6. It is noted that the carcinogenic risk of consuming yellow croaker, which is one of the most popular seafood among people on the east coast of China, was the highest. In conclusion, trophic magnification implied a possible elevated risk through this marine food chain, and overfishing may have increased the uncertainty associated with TMF estimations.

Occurrence of polycyclic aromatic hydrocarbons in the estuarine sediments of the Taihu Lake and their associated toxic effects on aquatic organisms

Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous toxic organic pollutants in the natural environment that are strongly associated with socioeconomic activities. Exploring the distribution, sources, and ecological toxicity of PAHs is essential to abate their pollution and biological risks. Sixteen priority PAHs in different lakeside city estuarine sediments in northern Taihu Lake in China were determined by gas chromatography-mass spectrometry. Results showed that total concentrations of PAHs (ΣPAHs) ranged from 672.07 to 5 858.34 ng g -1 , with a mean value of 2 121.37 ng g -1 . High-molecular-weight PAHs (4–6 rings) were dominant, accounting for 85% of the ΣPAHs detected. Due to the barrier of gate/dam in the estuarine area, the concentrations of PAHs in the sediments were significantly different between the river mouth and lake side. Changes in total organic carbon (TOC) content and the spatial distribution of PAHs in the sediments were consistent. Sediment pollution assessment explored using the fuzzy evaluation model indicated 75% of slight PAH pollution. Some estuarine sediments (22%) concentrated in the east of Wuli Lake were moderately or heavily polluted. The PAHs may lead to occasional detrimental biological consequences in the area. Diagnostic ratios and principal component analysis-multiple linear regression suggested vehicle emission and natural gas combustion as the primary PAH contributors (81%).

Influence of Source Apportionment of PAHs Occurrence in Aquatic Suspended Particulate Matter at a Typical Post-Industrial City: A Case Study of Freiberger Mulde River

Polycyclic aromatic hydrocarbons (PAHs) have received extensive attention because of their widespread presence in various environmental media and their high environmental toxicity. Thus, figuring out the long-term variances of their occurrence and driving force in the environment is helpful for environmental pollution control. This study investigates the concentration levels, spatial variance, and source apportionment of PAHs in suspended particulate matter of Freiberger Mulde river, Germany. Results show that the concentrations of the 16 priority PAHs suggested by USEPA (Σ16PAHs) were in the range of 707.0–17,243.0 μg kg−1 with a mean value of 5258.0 ± 2569.2 μg kg−1 from 2002 to 2016. The relatively high average concentrations of Σ16PAHs were found in the midstream and upstream stations of the given river (7297.5 and 6096.9 μg kg−1 in Halsbrucke and Hilbersdorf, respectively). In addition, the annual average concentration of Σ16PAHs showed an obvious decreasing pattern with time. Positive Matrix Factorization (PMF) receptor model identified three potential sources: coke ovens (7.6–23.0%), vehicle emissions (35.9–47.7%), and coal and wood combustion (34.5–47.3%). The source intensity variation and wavelet coherence analysis indicated that the use of clean energy played a key role in reducing PAHs pollution levels in suspended sediments. The risk assessment of ecosystem and human health suggested that the Σ16PAHs in the given area posed a non-negligible threat to aquatic organisms and humans. The data provided herein could assist the subsequent management of PAHs in the aquatic environment.