Polycyclic aromatic hydrocarbons (PAHs) in marine organisms from two fishing grounds, South Yellow Sea, China: Bioaccumulation and human health risk assessment

Phenanthrene perturbs hematopoietic development and causes hematopoietic defects in zebrafish

Phenanthrene (Phe) is one of the common polycyclic aromatic hydrocarbons in the environment, and recent studies show that it can cause cardiac developmental toxicity and immunotoxicity. However, it is still unknown whether it can affect the hematopoietic development in aquatic organisms. To address this question, zebrafish (Danio rerio) were chronically exposed to Phe at different concentrations. We found that Phe caused structural damage to the renal tubules in the kidney, induced malformed erythrocytes in peripheral blood, and decreased the proportion of myeloid cells in adult zebrafish, suggesting possible negative impacts that Phe posed to hematopoietic development. Then, using in situ hybridization technology, we found that Phe decreased the expression of primitive hematopoietic marker genes, specifically gata1 and pu.1, accompanied by an obstruction of primitive erythrocyte circulation. Furthermore, Phe impaired definitive hematopoiesis, increased aberrations of the transient hematopoietic site (PBI), and reduced the generation of hematopoietic stem cells, ultimately influencing the number of erythrocytes and myeloid cells. The findings suggested that Phe could induce hematopoietic toxicity in zebrafish embryos and pose unknown ecological risks.

Transformations of crude oil into tar: a case study from a plastitar-contaminated site in NE Sicily, Italy (Western Mediterranean)

This study examines the aging of industrial crude oil to simulate the chemical transformations that occur when it is exposed to environmental conditions over time. It was triggered by the finding of plastitar - a mixture of tar and plastic waste - on the coast of Milazzo, Sicily. Research began with a chemical characterization of the tar component of plastitar, followed by aging experiments designed to simulate environmental conditions such as seawater, UV light and sunlight. Fourier transform infrared spectroscopy (FTIR) was used to analyze the chemical changes during the aging process and compare the results with local tar samples. The results showed significant chemical changes in the aged crude oil, including oxidation, degradation of hydrocarbons and the formation of oxygenated compounds. In particular, the FTIR spectra of the aged crude oil closely matched those of the local tar and provided valuable insights that could help address similar coastal pollution issues in other regions.

Vertical distribution and influencing factors of soil PAHs under different ecosystem habitats in the Liaohe River Estuary Wetlands, Northeastern China

The vertical distribution, sources and influencing factors of polycyclic aromatic hydrocarbons (PAHs) in soil across ecosystem habitats were investigated around the Liaohe River Estuary (LRE) Wetland. The concentration of Ʃ16PAHs ranged from 41.0 to 435.4 ng g-1 dw, with a predominance of low molecular weight PAHs. Overall, PAHs and physicochemical properties of soil decreased with depth. Vegetation was found to increase soil PAHs. Additionally, soil physicochemical properties also regulated PAHs concentration, particularly for PAHs with high molecular weight. Among the habitats, total organic carbon was the key influencing factor for Suaeda heteroptera, while specific surface area was crucial for Phragmites australis. Results of characteristic ratio method and principal component analysis revealed that PAHs in LRE primarily originate petroleum, coal and biomass combustion. In summary, vegetation colonization significantly affected the distribution, sources, and controlling factors of PAHs. These findings are meaningful for management of soil PAHs across various ecosystem habitats.

Development of new PDMS in tube extraction microdevice for enhanced monitoring of polycyclic aromatic hydrocarbons and their derivatives in water

Contamination by polycyclic aromatic hydrocarbons (PAHs) is an urgent environmental concern, given its atmospheric dispersion and deposition in water bodies and soils. These compounds and their nitrated and oxygenated derivatives, which can exhibit high toxicities, are prioritized in environmental analysis contexts. Amid the demand for precise analytical techniques, comprehensive two-dimensional chromatography coupled with mass spectrometry (GCxGC/Q-TOFMS) has emerged as a promising tool, especially in the face of challenges like co-elution. This study introduces an innovation in the pre-concentration and detection of PAHs using an extraction fiber based on polydimethylsiloxane (PDMS), offering greater robustness and versatility. The proposed technique, termed in-tube extraction, was developed and optimized to effectively retain PAHs and their derivatives in aqueous media, followed by GCxGC/Q-TOFMS determination. Fiber characterization, using techniques such as TG, DTG, FTIR, and SEM, confirmed the hydrophobic compounds retention properties of the PDMS. The determination method was validated, pointing to a significant advancement in the detection and analysis of PAHs in the environment, and proved effective even for traces of these compounds. The results showed that the detection limits (LOD) and quantification limits (LOQ) ranged from 0.07 ng L-1 to 1.50 ng L-1 and 0.33 ng L-1 to 6.65 ng L-1, respectively; recovery ranged between 72 % and 117 %; and the precision intraday and interday ranged from 1 % to 20 %. The fibers were calibrated in the laboratory, with exposure times for analysis in the equilibrium region ranging from 3 to 10 days. The partition coefficients between PDMS and water were also evaluated, showing logarithm values ranging from 2.78 to 5.98. The fibers were applied to the analysis of real water samples, demonstrating high capacity. Additionally, given the growing demand for sustainable methods, the approach presented here incorporates green chemistry principles, providing an efficient and eco-friendly solution to the current chemical analysis scenario.

Bioaccumulation and potential human health risks of PAHs in marine food webs: A trophic transfer perspective

Polycyclic aromatic hydrocarbons (PAHs) are persistent pollutants in aquatic environments that can accumulate in marine organisms and pose potential health risks to humans through trophic transfer in the food webs. However, the accumulation and health risks of PAHs in organisms at different trophic levels remain unclear. This study investigated the accumulation and trophic transfer of PAHs in 40 marine organisms from Beibu Gulf (China), and assessed their health risks. Utilizing the trophic level spectrum constructed with stable isotope methods, the organisms were categorized into three trophic levels: Omnivorous (15.00 %), low-level carnivorous (67.50 %), and mid-level carnivorous (17.50 %). The contamination levels of total PAHs in these organisms ranged from "mild pollution" to "moderate pollution", with all organisms exhibiting significant PAH accumulation (Bioconcentration factor value > 2000). Total PAH concentrations increased with higher trophic levels, following the trend of mid-level carnivores > low-level carnivores > omnivores. Notably, only three PAH compounds (Nap, Fla and Phe) showed biomagnification effects, while the others exhibited trophic dilution. Carcinogenic risk assessment indicated an "Unacceptable risk" level for all populations, with the highest risk due to consumption of mid-level carnivorous. These findings offer new insights into the accumulation and health risks of PAHs from a trophic transfer perspective.

Polycyclic aromatic hydrocarbons in surface sediments of the western Bay of Bengal: Distribution, sources, and ecological risk assessment

This study investigated the distribution, sources, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the Western Bay of Bengal (WBoB). Coastal, shelf and slope sediments from the WBoB, collected from different research cruises, were analysed for 16 priority PAH pollutants. Total PAHs (TPAHs) were in the range of 1.87-918.79 ng/g and exhibited a significant association with organic matter and silt content with a predominance of high molecular weight (HMW) PAHs congeners. The preferential degradation of the labile low-molecular-weight (LMW) PAHs resulted in the sedimentary accumulation of HMW congeners. A comparison with reported values from other oceanic areas revealed a relatively low concentration of PAHs in WBoB. The isomeric ratios of PAHs could suggest a pyrogenic or petrogenic (crude oil) origin of PAHs. Principal component analysis indicated the dominance of HMW PAHs (petrogenic or combustion) over the LMW fraction. Based on sediment quality guidelines, four congeners [Pyrene (Py), Benzo[a]anthracene (BaA), Chrysene (Ch), and Dibenzo[a,h]anthracene (DbA)] exceeded the threshold effect levels, indicating an adverse impact of these PAHs on the benthic fauna occasionally. The corresponding risk quotients further indicated a moderate risk caused by Py, BaA, and Benzo[b]fluoranthene (BbF) to the biota. This study underscores the importance of proactive management and mitigation strategies to safeguard these vital oceanic ecosystems from the adverse effects of PAHs and other hazardous materials.

Peroxiredoxin 6 (Prx6) of Penaeus vannamei and effect of phenanthrene on Prx6 and glutathione peroxidase 4 expression, glutathione-dependent peroxidase activity and lipid peroxidation

Polycyclic aromatic hydrocarbons (PAHs), such as phenanthrene (PHE), are common pollutants found in coastal areas where shrimp farming is developed. Even though PAHs can have adverse effects on physiology, shrimp can detoxify and metabolize toxic compounds and neutralize the reactive oxygen species (ROS) produced during this process. This requires the activation of multiple antioxidant enzymes, including peroxiredoxin 6 (Prx6). Prx6 uses glutathione (GSH) to reduce phospholipid hydroperoxides, a function shared with GSH peroxidase 4 (GPx4). Prx6 has been scarcely studied in crustaceans exposed to pollutants. Herein, we report a novel Prx6 from the shrimp Penaeus vannamei that is abundantly expressed in gills and hepatopancreas. To elucidate the involvement of Prx6 in response to PAHs, we analyzed its expression in the hepatopancreas of shrimp sub-lethally exposed to PHE (3.3 μg/L) and acetone (control) for 24, 48, 72, and 96 h, along with GPx4 expression, GSH-dependent peroxidase activity, and lipid peroxidation (indicated by TBARS). We found that GPx4 expression is not affected by PHE, but Prx6 expression and peroxidase activity decreased during the trial. This might contribute to the rise of TBARS found at 48 h of exposure. However, maintaining GPx4 expression could aid to minimize lipid damage during longer periods of exposure to PHE.

Global geographical redistribution and source dynamics of selected semi-volatile organic compounds in the marine air boundary layer

The semi-volatile organic compounds (SVOCs), various priority pollutants of the marine air boundary layer (MABL), continue to elude full comprehension, creating substantial uncertainties about their global transport dynamics. We investigated 39 individual SVOCs during 3 large-scale Arctic and Antarctic expedition cruises. Our findings illuminate a discernable global gradient in their concentrations, with low molecular weight polycyclic aromatic hydrocarbons (PAHs) dominating. Interestingly, currently used pesticides (CUPs) have surpassed legacy organochlorine pesticides (OCPs) as primary pollutants. Despite international efforts to reduce emissions, SVOC mass inventories in polar regions have risen and are now identified as a significant source. The Westerlies disrupt SVOCs' global transport pathways, resulting in the "Westerly Wind Wall Block" effect, substantially influencing their redistribution in the Southern Hemisphere (SH). Our analysis ultimately underscores the pivotal roles of air-seawater exchange mechanisms and oceanic currents in the global transport dynamics of SVOCs within the MABL.

A vortex-assisted MSPD method for the extraction of Polycyclic Aromatic Hydrocarbons from shrimp with determination by GC-MS/MS

Polycyclic Aromatic Hydrocarbons (PAHs) are organic compounds with two or more condensed aromatic rings, formed from incomplete organic matter combustion. PAHs pose potential health risks due to their carcinogenic and mutagenic properties, accumulating in edible tissues of aquatic organisms, such as shrimp, which is extensively produced in the southern region of Rio Grande do Sul state (Brazil) and it is the most consumed seafood globally. Therefore, this study aimed to optimize and validate an analytical method for extracting 16 priority PAHs from shrimp samples using Vortex-Assisted Matrix Solid-Phase Dispersion (VA-MSPD) with determination by Gas Chromatography Tandem Mass Spectrometry (GC-MS/MS). The optimized method, which uses a reused solid support, was validated according to INMETRO and SANTE guidelines. PAHs demonstrated adequate linearity with correlation coefficients > 0.99. The matrix effect was assessed, and 12 out of the 16 PAHs showed a matrix effect of less than ±20%. The method's quantification limits ranged from 6.67 to 33.35 ng g-1. Accuracy and precision showed recovery values ranging from 55 to 115% with relative standard deviation (RSD) lower than 17% for all PAHs. In the applicability, 11 PAHs were detected, such as benzo[a]pyrene and benzo[b]fluoranthene, and the ∑PAHs ranged from 25.14 to 79.52 ng g-1, confirming the environmental contamination in the region and the need for monitoring these contaminants in shrimp destined for human consumption.

Distinct strategies of the habitat generalists and specialists in the Arctic sediments: Assembly processes, co-occurrence patterns, and environmental implications

Microorganisms could be classified as habitat generalists and specialists according to their niche breadth, uncovering their survival strategy is a crucial topic in ecology. Here, differences in environmental adaptation, community assemblies, co-occurrence patterns, and ecological functions between generalists and specialists were explored in the Arctic marine sediments. Compared to specialists, generalists showed lower alpha diversity but stronger environmental adaption, and dispersal limitation contributed more to the community assembly of specialists (74 %) than generalists (46 %). Furthermore, the neutral theory model demonstrated that generalists (m = 0.20) had a higher immigration rate than specialists (m = 0.02), but specialists exhibited more complex co-occurrence patterns than generalists. Our results also found that generalists may play more important roles in C, N, S metabolism but are weaker in carbon fixation and xenobiotic biodegradation and metabolism. This study would broaden our understanding of bacterial generalists' and specialists' survival strategies, and further reveal their ecological functions in marine sediments.

Bioaccumulation of polycyclic aromatic hydrocarbons and their human health risks depend on the characteristics of microplastics in marine organisms of Sanggou Bay, China

Microplastics pose a threat to marine environments through their physical presence and as vectors of chemical pollutants. However, the impact of microplastics on the accumulation and human health risk of chemical pollutants in marine organisms remains largely unknown. In this study, we investigated the microplastics and polycyclic aromatic hydrocarbons (PAHs) pollution in marine organisms from Sanggou Bay and analyzed their correlations. Results showed that microplastic and PAHs concentration ranged from 1.23 ± 0.23 to 5.77 ± 1.10 items/g, from 6.98 ± 0.45 to 15.07 ± 1.25 μg/kg, respectively. The microplastic abundance, particularly of fibers, transparent and color plastic debris, correlates strongly with PAH contents, indicating that microplastics increase the bioaccumulation of PAHs and microplastics with these characteristics have a significant vector effect on PAHs. Although consuming seafood from Sanggou Bay induce no carcinogenic risk from PAHs, the presence of microplastics in organisms can significantly increases incremental lifetime cancer risk of PAHs. Thus, microplastics can serve as transport vectors for PAHs with implications for the potential health risks to human through consumption. This study provides new insight into the risks of microplastics in marine environments.

Emerging and legacy contaminants on the Brazilian southern coast (Santa Catarina): A multi-biomarker approach in oysters Crassostrea gasar (Adanson, 1757)

Coastal environments, such as those in the Santa Catarina State (SC, Brazil), are considered the primary receptors of anthropogenic pollutants. In this study, our objective was to evaluate the levels of emerging contaminants (ECs) and persistent organic pollutants (POPs) in indigenous Crassostrea gasar oysters from different regions of SC coast in the summer season (March 2022). Field collections were conducted in the São Francisco do Sul, Itajaí, Florianópolis and Laguna coastal zones. We analyzed the bioaccumulation levels of 75 compounds, including antibiotics (AB), endocrine disruptors (ED), non-steroidal anti-inflammatory drugs (NSAIDs), polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and pesticides. Furthermore, we assessed biomarker responses related to biotransformation, antioxidant defense, heat shock protection and oxidative damage in oysters' gills. Prevalence of ECs was observed in the central and southern regions, while the highest concentrations of POPs were detected in the central-northern regions of SC. Oysters exhibited an induction in biotransformation systems (cyp2au1 and cyp356a1, sult and GST activity) and antioxidant enzymes activities (SOD, CAT and GPx). Higher susceptibility to lipid peroxidation was observed in the animals from Florianópolis compared to other regions. Correlation analyses indicated possible associations between contaminants and environmental variables in the biomarker responses, serving as a warning related to climate change. Our results highlight the influence of anthropogenic activities on SC, serving as baseline of ECs and POPs levels in the coastal areas of Santa Catarina, indicating more critical zones for extensive monitoring, aiming to conserve coastal regions.

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.

Sourcing aliphatic and polycyclic aromatic hydrocarbons (PAHs) in Jinga shrimp (Metapenaeus affinis) muscle tissues and surface sediments (study case: Northwest Persian Gulf)

This study addresses the sources of aliphatic hydrocarbons (AHs) and polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the northwestern Persian Gulf and the muscle tissues of Jinga shrimp (Metapenaeus affinis), a commercially important aquatic species. In November 2018, 28 Jinga shrimp samples were systematically collected from four key fishing areas in Behrgan and Khormusi: Imam Khomeini Port (S1), Mahshahr Port (S2), Sejafi (S3), and Behrgan Wharf (S4). Additionally, sediment samples were collected from these locations, and AHs and PAHs concentrations were analyzed using gas chromatography-mass spectrometry (GC-MS). The average aliphatic concentration in Jinga shrimp was 4800.32 (μg g-1 DW), exceeding the sediment samples' 2496.69 (μg g-1 DW) estimate. Hydrocarbon component analysis revealed EPA priority list (PAH-16) and measured PAHs (PAH-29) concentrations in Jinga shrimp ranging from 1095.8 to 2698.3 (ng g-1 DW) and in sediments from 653.6 to 1019.5 (ng g-1 DW). Elevated AHs and PAHs in Jinga shrimp, compared to sediments, suggest a petrogenic source, notably at station S4 near Behrgansar and Nowruz oil fields. Low molecular weight (LMW) compounds dominated in both shrimp and sediment PAHs. Aliphatic composition profiles in shrimps closely mirrored sediment profiles, illustrating an even-to-odd carbon dominance gradient. Diagnostic ratio examinations of hydrocarbons indicated pervasive petroleum derivatives in the environment. This study establishes a direct correlation between hydrocarbon concentrations in shrimp and sediment samples and the corresponding aliphatic groups, PAH-16, and PAH-29. The findings underscore the potential of Jinga shrimp as a reliable indicator of hydrocarbon pollution in the northwestern Persian Gulf.

Polycyclic aromatic hydrocarbons in coastal rivers in Jiangsu Province, China: Spatial distribution, source apportionment and human impacts

The ocean is the ultimate sink for all pollutants, rivers are important channels for land-based pollutants to enter the oceans. Riverine transport of polycyclic aromatic hydrocarbons (PAHs) to coastal seas in China poses environmental threats. This study examined the spatial and temporal distribution of PAHs in coastal rivers in Yancheng City in Jiangsu Province of China, with the aim of identifying their likely sources, concentrations, and influencing factors. Surface sediments were taken from the Xinyanggang River (XYR) and the Sheyang River (SYR). The concentrations of Ʃ16PAHs in river sediments were measured on average 477.05 ng/g dry weight (dw), with values varying from 2.18 to 6351.42 ng/g, indicating a moderate pollution level, with a dominance of high molecular weight (HMW) PAHs. The XYR exhibited significantly higher PAHs concentrations compared to the SYR. The key sources of PAHs were vehicle emissions (47.87%), coal and natural gas combustion (35.07%). Geographically weighted regression and redundancy analysis linked PAHs pollution to distinct land use patterns and socioeconomic indicators, highlighting urban land as the major contributor, driven by high urbanization and industrialization (70.91%). In XYR, industrial activities and transport emissions were major contributors, while in SYR, agricultural activities predominantly influenced PAHs pollution. Urgent mitigation strategies are needed to reduce PAHs pollution in river sediments, mitigating ecological and human risks associated with these contaminants.

Occurrence, sources and risk assessment of polycyclic aromatic hydrocarbons in the coral reef waters of the Lakshadweep Archipelago, Arabian Sea

The compound effects of anthropogenic disturbances on global and local scales threaten coral reef ecosystems of the Arabian Sea. The impacts of organic pollutants on the coral reefs and associated organisms have received less attention and are consequently less understood. This study examines the background levels, sources, and ecological implications of polycyclic aromatic hydrocarbons (PAHs) in the coral reef ecosystems of Lakshadweep Archipelago. Water and particulate matter were collected from four coral Islands (Kavaratti, Agatti, Bangaram and Perumal Par) of Lakshadweep Archipelago during January and December 2022 and analysed for 15 PAHs priority pollutants. The 15 PAHs congeners generally ranged from 2.77 to 250.47 ng/L in the dissolved form and 0.44 to 6469.86 ng/g in the particulate form. A comparison of available data among the coral reef ecosystems worldwide revealed relatively lower PAHs concentrations in the Lakshadweep coral ecosystems. The isomeric ratios of individual PAH congeners and principal component analysis (PCA) indicate mixed sources of PAHs in the water column derived from pyrogenic, low-temperature combustion and petrogenic. The risk quotient (RQ) values in the dissolved form indicate moderate risk to the aquatic organisms, while they indicate moderate to severe risk in the particulate form.

Persistent organic pollutants (POPs) in marine crustaceans: Bioaccumulation, physiological and cellular responses

Persistent organic pollutants (POPs) are ubiquitous in marine ecosystems. These compounds can be accumulated in water, sediments and organisms, persist in time, and have toxic effects in human and wildlife. POPs can be uptaken and bioaccumulated by crustaceans, affecting different physiological processes, including energy metabolism, immunity, osmoregulation, excretion, growth, and reproduction. Nonetheless, animals have evolved sub-cellular mechanisms for detoxification and protection from chemical stress. POPs induce the activity of enzymes involved in xenobiotic metabolism and antioxidant systems, that in vertebrates are importantly regulated at gene expression (transcriptional) level. However, the activation and control of these enzyme systems upon the exposure to POPs have been scarcely studied in invertebrate species, including crustaceans. Herein, we summarize various aspects of the bioaccumulation of POPs in marine crustaceans and their physiological effects. We specially focus on the regulation of xenobiotics metabolism and antioxidant enzymes as key sub-cellular mechanisms for detoxification and protection from chemical stress.

Residue character of polycyclic aromatic hydrocarbons in river aquatic organisms coupled with geographic distribution, feeding behavior, and human edible risk

Polycyclic aromatic hydrocarbons (PAHs) residues in fish, shrimp and shellfish have attracted attention because they are major species in the aquatic food chain and an important food source for humans. These organisms have various feeding habits and different living environments, and through the food chain, they can directly or indirectly connect particulate organic matter and human consumption. However, little attention has been paid to the bioaccumulation of PAHs in aquatic organism groups representing varied conditions and feeding habits in the food chain. In this study, 17 species of aquatic organisms, comprising fish, shrimp, and shellfish, were captured from 15 locations distributed within the river network of the Pearl River Delta. The concentration of 16 PAHs was measured in the aquatic organisms. The sum of the 16 measured PAHs ranged from 57.39 to 696.07 ng/g, dry weight, while phenanthrene had the highest individual content. The linear mixed effect model was applied to estimate the random effects of PAH accumulation in aquatic organisms. The result showed that the contributed proportion of variance to feeding habits (58.1 %) was higher than that of geographic distribution (11.8 %). In addition, one-way analysis of variance (ANOVA) demonstrated that the concentrations of PAHs depended on the water layer inhabited by the organism and its species status. Specifically, shellfish and carnivorous bottom-dwelling fish showed significantly higher levels than other aquatic organisms.

Occurrence and distribution of polycyclic aromatic hydrocarbons (PAHs) in marine organisms from Shenzhen coastal waters and human health risk assessment

This study investigated the levels and composition of 16 priority polycyclic aromatic hydrocarbons (PAHs) in marine organisms from South China Sea and assessed their potential health risks. The results revealed that the pollution levels of total PAHs ranged from 3.56 to 392.21 ng/g dw. Notably, 4-ring PAHs constituted the predominant fraction (58.02 %) of the total PAHs, with pyrene being the most abundant congener across all species. Intriguingly, our findings suggested that consuming these organisms might pose a low non-cancer hazard. Nonetheless, benzo[a]pyrene was detected in most species, with levels ranging from non-detectable to 11.24 ng/g dw. The individual lifetime cancer risk levels associated with seafood consumption in studied regions ranged from 1.10 × 10-5 to 1.52 × 10-5, highlighting a potential cancer risk that warrants special attention. These findings emphasize the need to prioritize carcinogenic compounds over total PAHs and underscore the importance of continuous monitoring of PAH pollution in seafood.

PM2.5 exposure promotes asthma in aged Brown-Norway rats: Implication of multiomics analysis

Children are disproportionately represented among those who suffer asthma, which is a kind of chronic airway inflammation. Asthma symptoms might worsen when exposed to the air pollutant particulate matter 2.5 (PM2.5). However, it is becoming more prevalent among older adults, with more asthma-related deaths occurring in this pollution than in any other age group, and symptoms caused by asthma can reduce the quality of life of the elderly, whose asthma is underdiagnosed due to physiological factors. Therefore, in an effort to discover a therapy for older asthma during exposure to air pollution, we sought to ascertain the effects of pre-exposure (PA) and persistent exposure (PAP) to PM2.5 in aged asthma rats. In this study, we exposed aged rats to PM2.5 at different times (PA and PAP) and established an ovalbumin-mediated allergic asthma model. The basic process of elderly asthma caused by PM2.5 exposure was investigated by lung function detection, enzyme-linked immunosorbent assay (ELISA), histopathology, cytology, cytokine microarray, untargeted metabolomics, and gut microbiota analysis. Our findings demonstrated that in the PA and PAP groups, exposure to PM2.5 reduced lung function and exacerbated lung tissue damage, with varying degrees of effect on immunoglobulin levels, the findings of a cytological analysis, cytokines, and chemokines. The PA and PAP rats had higher amounts of polycyclic aromatic hydrocarbons (PAHs), such as naphthalene, 2-methylNaphthalene, 1-methylNaphthalene and flourene. Moreover, exposure to PM2.5 at different times showed different effects on plasma metabolism and gut microbiota. Bioinformatics analysis showed a strong correlation between PAHs, cytokines, and gut microbiota, and PAHs may cause metabolic disorders through the gut microbiota. These findings point to a possible mechanism for the development of asthma in older people exposure to PM2.5 that may be related to past interactions between PAHs, cytokines, gut microbiota, and plasma metabolites.

Trophodynamics and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in marine food web from Laizhou Bay, China

Here, we collected 16 species (n = 298) from Laizhou Bay, China to investigate the trophodynamics, bioaccumulation and cancer risks of polycyclic aromatic hydrocarbons (PAHs). Results demonstrated that naphthalene was the most abundant PAH, followed by phenanthrene and fluorene in the marine organisms. The sum of 16 PAHs concentrations (Ʃ16PAHs) ranked with algae (19,435 ng·g-1 lipid weight, lw) > benthonic animals (6599 ng·g-1 lw) > fish (1760 ng·g-1 lw). Combustion and oil spill are two primary sources, contributing 60.3 % and 39.7 % of Ʃ16PAHs, respectively. High values of log BAF were found for 4-6 rings PAHs. Algae and benthonic animals showed a high ability to accumulate 2-4 rings PAHs and 5-6 rings PAHs, respectively. A biodilution pattern for PAHs was found in the marine food web. The carcinogenic risks of some benthos and fish were higher than 1 × 10-6, threatening resident health by consumption of these seafoods.

Source apportionment and human health risk of PAHs accumulated in edible marine organisms: A perspective of "source-organism-human"

Most PAHs produced by human activities can be absorbed and accumulated by edible organisms and pose a potential hazard to human health. However, the source apportionment and human health risk of PAHs accumulated in edible organisms remains largely unknown. Therefore, we conducted source analysis and health risk assessment based on the PAH concentrations in ten marine fish from coastal areas of Guangdong, China. Results showed that the pollution of PAHs in fish organisms was at "Minimally polluted" level, and that all marine fish had the ability to accumulate PAHs. Risk assessment indicated Carcinogenic risk of PAHs in four populations was at a "Cautionary risk" level, with urban children suffered the highest risk. Petroleum pollution, Coal and biomass combustion, and Marine transport emissions were identified as the main anthropogenic sources for PAHs in organisms, and Marine transport emissions accounted for the highest Carcinogenic risk. The Acceptable daily intake for all populations were far below their actual daily intake without causing "Cautionary risk". Our findings provide new insights into the source apportionment and health risk of PAHs from a "source-organism-human" perspective, and suggested that joint management of three anthropogenic sources would be an effective way to prevent the health risks of PAHs.

Trophic transfer of polycyclic aromatic hydrocarbons in marine mammals based on isotopic determination

The tissue distribution (liver, kidney, heart, lung, and muscle), source, and trophic transfer of 15 polycyclic aromatic hydrocarbons (PAHs) were studied on 14 stranded East Asian finless porpoises (Neophocaena asiaeorientalis sunameri), 14 spotted seals (Phoca largha), and 9 stranded minke whales (Balaenoptera acutorostrata) from Yellow Sea and Liaodong Bay. The PAHs levels ranged from below the limit of detection to 459.22 ng g^-1 dry weight in the tissues of the three marine mammals, and light molecular weight PAHs were the primary pollutants. Although the PAHs levels were relatively higher in internal organs of the three marine mammals, generally no tissue-specific distribution of the PAHs congeners was found, either for gender-specific distribution of PAHs in the East Asian finless porpoises. However, species specific PAHs concentration distribution were obtained. The PAHs were mainly originated from petroleum and biomass combustion in the East Asian finless porpoises, while those for the spotted seals and minke whales were complex. Trophic level associated biomagnification was found for phenanthrene, fluoranthene, and pyrene in the minke whale. Benzo(b)fluoranthene exhibited a significant biodilution with increasing trophic levels in the spotted seals, but the total concentration of the PAHs showed a significant biomagnification with increasing trophic levels. Trophic level-associated biomagnification of acenaphthene, phenanthrene, anthracene, and ∑PAHs were found in the East Asian finless porpoise, while pyrene exhibited obvious biodilution with increasing trophic levels. Our current study filled knowledge gaps on tissue distribution and trophic transfer of the PAHs in the investigated three marine mammals.

First study of bromophenols and hexabromocyclododecanes in seafood from North Africa (case of Bizerte Lagoon, Tunisia): occurrence and human health risk

In spite of the fact that bromophenols (BPs) and hexabromocyclododecanes (HBCDs) are widely used as flame retardants, no data was available until now on the levels of these two chemicals in North Africa biota. Seafood products might represent one of the main sources of dietary exposure to persistent organic pollutants such as non-dioxin-like polychlorinated biphenyls (ndl-PCBs), brominated flame retardants (BFRs), and polycyclic aromatic hydrocarbons (PAHs). In this study, the concentrations of the ndl-PCBs, PAH₄, and BFRs were determined in seafood products from a North African lagoon (Bizerte lagoon). Almost all the compounds were detected (15 out of 18) in the analyzed marine organisms. The accumulation of the contaminants followed the order BFRs > ndl-PCB > PAH₄. Mean contaminants concentrations ranged from 0.35 to 28.7 ng g^-1 ww for ∑ndl-PCBs; from below limit of quantification to 476 ng g^-1 ww for ∑BFRs and from below limit of quantification to 5.30 ng g^-1 ww for ∑PAH₄. PCB 138, 153, and 180 were the most frequently detected ndl-PCB congeners due to their high resistance to metabolic degradation. 2,4-dibromophenol (2,4-DBP) was the predominant BFR. Chrysene (Chr) was found to be the main contributor to the total PAH₄ concentration. Contaminant profiles varied significantly among seafood which may be due to the difference in lipid content, trophic level, feeding behavior, and metabolism. To assess the human health risks, the average daily dose exposure of ndl-PCBs, the dietary daily intake of PAHs and the estimated dietary intake of 3,3-,5,5-tetrabromobisphenol A (TBBPA) and HBCD from seafood were estimated. Findings indicated no adverse effects for human health from any of the analyzed contaminants, except for ndl-PCBs in eel.

Metallic nanoparticles affect uptake of polycyclic aromatic hydrocarbons and impacts in the Mediterranean mussels Mytilus galloprovincialis

The impact of metallic nanoparticles (NPs) on the uptake and toxicity of persistent organic pollutants by marine bivalves was assessed through a comparative laboratory study by exposing mussels to polycyclic aromatic hydrocarbon (PAHs), in the presence and absence of ZnO and TiO₂ NPs. PAHs and NPs concentration was analyzed after 14 days of exposure in mussels by GC/MS and ICP/AES. Furthermore, impact on the physiology and neurotoxicity of PAHs and NPs acting alone or in mixtures were also determined. Our results confirmed the bio-uptake of PAHs and NPs by mussels. In addition, the exposure NPs-PAHs resulted in different bio-uptake profile to that of PAHs alone. The NPs and accumulation of PAHs led to disturbance of essential metals concentration and to different impact profiles in the filtration and respiration capacities as well as in the acetylcholinesterase activity. Antagonist interactions between NPs and PAHs could occur after exposure.

Potential of microplastics participate in selective bioaccumulation of low-ring polycyclic aromatic hydrocarbons depending on the biological habits of fishes

Currently, although the cumulative effects of microplastics (MPs) and organic pollutants (OPs) in the environment and within organisms are being investigated, whether and how MPs participate in bioaccumulation of OPs based on a carrier effect is still unclear. In the present study, water and aquatic organisms were collected from the Pearl River. Polycyclic aromatic hydrocarbons (PAHs) and MPs were separated by solid phase extraction and were measured by gas chromatography mass spectrometry and Fourier transform infrared spectroscopy, respectively. Higher PAH concentrations at the river outlet and higher MPs abundance in the inner river were observed, indicating a mismatched distribution between PAHs and MPs. No correlation between MP abundance and PAH concentration in fishes was detected, implying that MPs exerted limited influence on PAH concentrations. Interestingly, bioconcentration factors of one major low-ring PAH (phenanthrene) in fishes showed a significant correlation with MPs abundance, implying that although MPs did not affect the variation in PAH concentrations, they potentially participated in selective bioaccumulation of PAHs. Moreover, significant correlations between MPs abundance and PAHs in fishes with different feeding and living habits were found, indicating that MPs' participation in PAH bioaccumulation was dependent on fish biology and life history. Furthermore, the health risk posed by PAHs in fishes at the river outlet surpassed the line of potential high risk, while the ecological risk posed by MPs at the inner river was in the danger category, indicating the ecological risks posed by PAHs and MPs are uneven along the Pearl River. These findings deepen our understanding of the underlying mechanism of MPs participating in selective bioaccumulation of low-ring PAHs in fishes based on fish biology and point out the present risks posed by these two pollutants in the Pearl River and its estuary, which contribute to aquatic environmental protection and fishery production in this region.

Significance of the great protection of the Yangtze River: Riverine input contributes primarily to the presence of PAHs and HMs in its estuary and the adjacent sea

The Yangtze River protection strategies are expected to improve the water quality and ecological function of the Yangtze River Estuary (YRE). The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) and 6 heavy metals (HMs) in the YRE were measured and the riverine fluxes were calculated subsequently. In particular, the concentrations of low molecular weight PAHs (LMW-PAHs), arsenic (As) and mercury (Hg) in seawater decreased over time, while those of other studied pollutants did not change a lot. In sediments, the concentration changes for all the pollutants were insignificant. For the present pollutants, the river input is the dominant source, and the flux decreased after the protection. The contribution of the discharge from wastewater treatment plants (WWTPs) was quantified. Its influence cannot be ignored. The seafood quality remained stable and the risk via diet was insignificant. Long-term monitoring is necessary, and the positive impact of the Protection Strategy is gradually emerging.

Occurrence of mercury in polychaete species (Annelida) and their associated sediments from an important Southern Atlantic Ocean Bay

In the present study, the Hg levels in freshly collected polychaete species and their associated sediments were evaluated from Todos os Santos Bay, Northeastern Brazil. Additionally, it was also measured the Hg distribution along the annelids' body parts (anterior region, abdomen, and posterior region). Total Hg concentration was as follows: 13.6-144 μg kg^-1 (Scolelepis chilensis, deposit feeder), 8.2-122 μg kg^-1 (Laeonereis acuta, deposit feeder), 95-612 μg kg^-1 (Armandia agilis, deposit feeder); 96.6-206 μg kg^-1 (Lumbrineris sp., carnivorous), 75.3-112 μg kg^-1 (Goniada echinulate, carnivorous), and 115-198 μg kg^-1 (Branchiomma sp., suspension feeder). In turn, Hg levels in sediments ranged from 2.77 ± 0.24 to 6.38 ± 0.15 μg kg^-1. Hg concentrations found in polychaete soft tissues were higher than those found in the sediments. Specific habits, feeding behavior, trophic level, and stressful environmental conditions are the main factors affecting the Hg levels in the species studied. The bioaccumulation factor (BAF), contamination factor (CF), and ecological risk assessment (Er) were calculated. The BAF values were higher than 1 for all studied species, indicating Hg bioaccumulation in the annelids, but the low levels of CF e Er showed those Hg levels present low to no significant ecological risk for the biota and benthonic organisms living in the sediments. Finally, no statistically significant difference was observed for Hg concentration levels along the polychaete body parts.

Horizontal and vertical segregation of polycyclic aromatic hydrocarbons in the Egyptian Mediterranean coast

Egyptian Mediterranean coast receives significant amounts of polycyclic aromatic hydrocarbons (PAHs) from industrial exhausts, riverine inputs, maritime shipping and fishers, and oil and natural gas production and exploration. The present study considers the first exhaustive assessment for the dissolved PAHs along the Egyptian Mediterranean coast (Alexandria to Manzallah) to monitor their spatial distribution and investigate the effect of the marine currents and the role of microorganisms in their distribution. Surface water levels ranged between 124.97 and 301.02 ng L^-1 with an average 223.68 ± 41.11 ng L^-1. The distribution increases from west to east based on the water circulation in the Mediterranean Sea. The levels in near shore stations were lower than those of middle and onshore stations. The intensive existence of micro-organisms near shore stations consumes great part of PAHs, while this bio-remediation process decreases gradually away from the shoreline leaving relative high concentrations of dissolved PAHs in the middle and onshore stations. Middle and deep-water levels ranged between 312.75 and 1042.95 ng L^-1 with an average 633.47 ± 225.53 ng L^-1. Deeper waters showed higher PAHs concentrations where the average concentrations of 50 m stations (868.12 ± 138.35 ng L^-1) ˃ 30 m stations (629.49 ± 143.85 ng L^-1) ˃ 10 m stations (402.79 ± 59.46 ng L^-1). The wind-induced waves re-suspend rich PAHs sediment particles to increase its concentration in the water column. Carcinogenic toxic equivalent quotient (TEQ) for total detected PAHs in the middle and deep water represented more than double (75.46 ng TEQ L^-1) the value in the surface water (34.76 ng TEQ L^-1). The diagnostic ratios and principal component analysis indicated mainly pyrogenic origin in surface, middle, and deep waters.

The response of meiobenthinc sediment-dwelling nematodes to pyrene: Results from open microcosms, toxicokinetics and in silico molecular interactions

An experiment conducted with 'open microcosm' made by connected sedimentary compartments with different qualities was for 30 days to evaluate the migratory behaviour of nematodes as induced by exposure to pyrene. The nematofauna was collected along with sediment from a reference site in Bizerte lagoon. Following one week acclimatization period, the populated sediments were topped with azoic sediments, with a pyrene concentration of 150 μg kg^-1. The concentration of pyrene from sediments was measured on a weekly basis. A stable status of nematode assemblages was reached between the upper and lower compartments in each microcosm, whatever the treatment type. An upward exploratory phase was observed during the first two weeks within the assemblages, possibly induced by the repellent chemodetection of pyrene. This observation was confirmed by the toxicokinetic properties and molecular interactions of pyrene with the germ-line development Protein 3 and sex-determining protein of Caenorhabditis elegans as nematode model.

Polycyclic aromatic hydrocarbons (PAHs) in the Bohai Sea: A review of their distribution, sources, and risks

The distribution, risks, and sources of polycyclic aromatic hydrocarbons (PAHs) observed in seawater and sediments in the Bohai Sea were reviewed. The ecological risk of total PAHs in seawater was low, but the ecological risks of several individual PAHs (Pyr, BbF, and IcdP) were high. Detected PAHs in sediments rarely had adverse biological effects. High PAH concentrations were identified in Bohai Bay, in the sea area near Qinhuangdao, in Jinzhou Bay, and in Bohai Strait. Low PAH concentrations were found in the central Bohai, in Laizhou Bay, and in the sea area with more intensive ocean currents near Caofeidian. PAH concentrations in the Bohai Sea present a seaward-decreasing trend. Their spatial distribution could be attributed to the influence of human activities (population, industrial activities, and shipping activities), which determined PAH emissions. The PAHs were characterized by local sources, indicating that coal consumption and vehicle emissions were important sources of PAHs. Integr Environ Assess Manag 2022;18:1705-1721. © 2022 SETAC.

Al-Dalain S, Al-Dmour R, Alahmad A, Batarseh MI. Accumulation, Source Identification, and Cancer Risk Assessment of Polycyclic Aromatic Hydrocarbons (PAHs) in Different Jordanian Vegetables

The accumulation of polyaromatic hydrocarbons in plants is considered one of the most serious threats faced by mankind because of their persistence in the environment and their carcinogenic and teratogenic effect on human health. The concentrations of sixteen priority polycyclic aromatic hydrocarbons (16 PAHs) were determined in four types of edible vegetables (tomatoes, zucchini, eggplants, and cucumbers), irrigation water, and agriculture soil, where samples were collected from the Jordan Valley, Jordan. The mean total concentration of 16 PAHs (∑16PAHs) ranged from 10.649 to 21.774 µg kg−1 in vegetables, 28.72 µg kg−1 in soil, and 0.218 µg L−1 in the water samples. The tomato samples posed the highest ∑16PAH concentration level in the vegetables, whereas the zucchini samples had the lowest. Generally, the PAHs with a high molecular weight and four or more benzene rings prevailed among the studied samples. The diagnostic ratios and the principal component analysis (PCA) revealed that the PAH contamination sources in soil and vegetables mainly originated from a pyrogenic origin, traffic emission sources, and biomass combustion. The bioconcentration factors (BCF) for ∑16PAHs have been observed in the order of tomatoes > cucumbers and eggplants > zucchini. A potential cancer risk related to lifetime consumption was revealed based on calculating the incremental lifetime cancer risk of PAHs (ILCR). Therefore, sustainable agricultural practices and avoiding biomass combusting would greatly help in minimizing the potential health risk from dietary exposure to PAHs.

Spatial dynamics of prokaryotic microbial communities in sediments of the Yellow Sea: Assembly process, co-occurrence relationships, and environmental implications

Marine sediment microorganisms play an important role in the biogeochemical cycle of elements and the transformation of exogenous pollutants; therefore, it is important to study the microbial assembly process and inter taxa associations. In this study, we investigated the profiles and assembly processes of microbial communities of sediments collected from 19 points in the Yellow Sea. As revealed by 16S rRNA sequencing, Proteobacteria (43.11%-65.54%) was the dominant phylum in marine sediment. Further, the physicochemical properties of sediments were significantly influenced by depth (P < 0.05), and the effects of homogeneous selection became greater with increasing depth. The microbial species located in marine sediment at 35°N had a significantly higher co-occurrence relationship (82.76%) than those at 34°N (57.99%) and 36°N (54.07%). Additionally, the microbial community structure of the sediments changed significantly at the genus level with strong fluctuations in the physicochemical properties. By contrast, the carbon, nitrogen, and sulfur associated functional gene diversity and abundance showed no clear variation among different locations, indicating the probable functional redundancy and a potential functional gene pool of the microbes in marine sediments. This study could provide new insights into the composition of microorganisms in sediments in the Yellow Sea, the driving force of microbial diversity, the assembly process, the modes of species' co-occurrence, and their ecological functions.

Development of seawater quality criteria for phenanthrene based on toxicity data of native species in the Bohai Sea

Phenanthrene (Phe), one of the most commonly detected polycyclic aromatic hydrocarbons, poses a potential threat to marine ecosystems due to its strong toxicity to aquatic organisms. Developing marine water quality criteria (WQC) is critical to effectively control Phe pollution. This study conducted 10 acute toxicity tests and 4 chronic toxicity tests using native species in the Bohai Sea, China and found that the half-lethal/effective concentrations (LC₅₀/EC₅₀) of Phe for all tested organisms were in the range of 0.198-50.142 mg/L. Among them, the mysid Neomysis awatschensis was the most sensitive species, and the rotifer Brachionus plicatilis was the least sensitive. In terms of chronic toxicity, the range of no-observed-effect concentrations (NOECs) for the four tested organisms was 0.0156-4.00 mg/L. Based on the toxicity data and other data collected from existing databases and literature, the established species sensitivity distribution (SSD) model revealed that the marine WQC for Phe was 39.55 μg/L. Furthermore, the reliability of the derived criteria was verified by measuring multiple endpoints of Skeletonema costatum and Brachionus plicatilis after chronic exposure to Phe. Finally, the environmental concentrations of Phe in the Bohai Sea were determined to be 8.0-318 ng/L, and the joint probability curve (JPC) results showed that the ecological risk of Phe was acceptable. This study provides a reference for developing seawater quality standards for Phe.

Simulation modelling the structure related bioaccumulation and biomagnification of per- and polyfluoroalkyl substances in aquatic food web

Until now, there is no bioaccumulation model to predict bioaccumulation of polyfluoroalkyl substances (PFASs) in aquatic organisms due to their unique amphiphilic properties. For the first time, protein contents instead of lipid contents of organisms were used in bioaccumulation models to predict the concentrations and reveal the accumulation mechanisms of PFASs in various aquatic organisms, based on the available data. Comparison between the modeled and measured results indicated the models were promising to predict the PFAS concentrations in the fishes at different trophic levels very well, as well as their bioaccumulation factors (BAF) and trophic magnification factors (TMF) of PFASs in fish. Both water and sediment are important exposure sources of PFASs in aquatic organisms. As the two main uptake pathways, the contribution of gill respiratory decreases while that of dietary intake increases with the chain length of PFASs increasing. Fecal excretion and gill respiration are the main pathways for fish to eliminate PFASs, and their relative contributions increase and decrease respectively with chain length. The short-chain (C6-C8) perfluoroalkyl acids (PFAAs) are greatly eliminated via gill respiratory quickly, leading to their very low BAFs. As the carbon chain length increases, dietary intake becomes dominant in the uptake, while elimination is mainly through fecal excretion with relatively low rates, especially in the fishes with high protein contents. For the very long chain (C12-C16) PFASs, they are very difficult to excrete with a low total elimination rate constant (k_e = 0.463-0.743 d^-1), thus leading to their high BAFs and TMFs. The high intake rate but low elimination rate, as well as the high water and sediment concentrations together contribute to the highest accumulated concentration perfluorooctane sulfonic acid in the fish of Taihu Lake.

Analysis of polycyclic aromatic hydrocarbons (PAHs) in surface sediments and edible aquatic species in an oil-contaminated mangrove ecosystem in Bodo, Niger Delta, Nigeria: Bioaccumulation and human health risk assessment

This work investigated the occurrence and risks associated with polycyclic aromatic hydrocarbons (PAHs) in tissues from five commonly consumed aquatic species (swimming crabs, estuarine shrimp, tiger prawns, periwinkles, and tilapia) and sediment across six sites in the area around Bodo town, in the Niger Delta region of Nigeria. We aimed to establish a relationship between PAH concentrations in sediment and biota, and to derive biota-sediment accumulation factors (BSAFs). Risks to human health associated with consumption of impacted food sources were assessed based on measured biotic concentrations of PAHs. The average concentration of PAHs and the number of PAHs measured above the limit of quantification varied greatly between different biota, with the lowest average concentrations observed in tilapia, followed by tiger prawns, crabs, estuarine shrimp, and the highest concentrations were observed in periwinkles. Similar to biotic concentrations, BSAFs were found to vary greatly across species, sites, and PAHs, though BSAFs for all organisms except periwinkles were below a value of 1. In periwinkles, BSAFs exceeded a value of 1 for phenanthrene (BSAF = 1.7), pyrene (1.5) and benzo[k]fluoranthene (1.7). Risks to human health associated with consumption of these species were assessed using the BaP toxic-equivalent approach for cancer risks and the toxic unit approach which jointly considered carcinogenic but also non-cancer hazards. The BaP toxic-equivalent approach showed that the excess lifetime cancer risk resulting from daily consumption of 0.2 kg of seafood ranged between 1.3 × 10^-6 for tiger prawn and tilapia to 4.1 × 10^-6 for periwinkles, which is below the excess lifetime cancer risk of 10^-4 used by Dutch and Nigerian authorities for sediment intervention values. This finding is supported by the results obtained from the toxic unit approach which indicates that the ratios of the estimated dose and the maximal permissible risk level for summed PAHs never exceeded 1.

Phase partitioning effects on seasonal compositions and distributions of terrigenous polycyclic aromatic hydrocarbons along the South China Sea and East China Sea

Polycyclic aromatic hydrocarbons (PAHs) have posed serious risk to marine ecosystems due to their carcinogenic properties, and persistence in the environment and elevated bioaccumulation. It, therefore, becomes essential to examine spatial distribution, composition, and sources of PAHs. In this study, we have examined these PAH variations in the South China Sea (SCS) and East China Sea (ECS), that are experiencing rapid population and economic growth by the surrounding developing countries. It revealed high seasonal variations that significantly differ between dissolved and particulate PAHs concentrations. Spatial variations of PAHs across sites remain relatively insignificant. Persistently high particulate concentrations of the Naphthalene (Nap) were observed, whereas the dissolved concentrations of Fluorene (Flu) and Phenanthrene (Phen) remained prevalent across all the seasons. The result of non-metric multidimensional scaling (NMDS) strongly reflects the weak dispersions of PAHs across the seasons and the contrasting effects of the phase partitioning. Principal component analysis indicates that the primary source of PAH contamination is coal tar or petroleum distillation. However, estimated risk quotient (RQ) values of both the dissolved and particulate PAHs in all the seasons are far below the high-risk levels, while dissolved PAHs displayed relatively higher values. This study signifies the importance of phase petitioning for PAHs monitoring and potential risk assessments.

Atmospheric concentration, spatial variations, and source identification of persistent organic pollutants in urban and semi-urban areas using passive air samplers in Bursa, Turkey

In this study, the concentration of ambient persistent organic pollutants (POPs) such as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured for 12 months in urban and semi-urban areas using a passive air sampler. During the sampling period, a total of 14 PAH (∑₁₄PAH) concentrations measured in urban and semi-urban areas were found to be 54.4 ± 22.6 ng/m³ and 51.7 ± 34.3 ng/m³, respectively. Molecular diagnostic ratios (MDRs) were used to determine PAH sources. According to the MDR values, combustion sources were the most important PAH sources in both sampling areas. However, since the urban area is close to the industrial zone, the combustion sources occurred at high temperatures (> 800 °C), while the sources in the semi-urban area generally consisted of petrogenic fuel combustion. ∑₅₀PCB concentrations measured in the urban and semi-urban areas were found to be 522.5 ± 196.9 pg/m³ and 439.5 ± 166.6 pg/m³, respectively. Homologous group distributions were used to determine the source of PCBs. According to the homologous group distributions, tri-, tetra-, and penta-chlorinated PCBs were dominant in both sampling areas. ∑₁₀OCP concentrations measured in urban and semi-urban areas were found as 242.5 ± 104.6 pg/m³ and 275.9 ± 130.9 pg/m³, respectively. Also, α-HCH/γ-HCH and β-/(α + γ)-HCH ratios were used to determine the source of OCPs. Lindane was the predominant OCP in both sampling areas.

Occurrence and patterns of nutritional traits and polycyclic aromatic hydrocarbons (PAHs) in sea cucumber (Holothuria polii) tissues: benefits and risk for human health

Objectives

The paper evaluated the benefit and risk for human health associated with consumption of sea cucumber H. polii from Italian coasts (Central Mediterranean Sea).

Materials and Methods

body wall-BW, internal tunic-ITu, muscle bands-MB, alimentary canal-AC, gonad-Gd and respiratory tree-RT of H. polii were analyzed for proximate composition. Moreover, aminoacids, fatty acids and polycyclic aromatic hydrocarbons (PAHs) were determined with HPLC UV/Vis, GC-FID and GC-MS, respectively.

Results

Differences in the contents of Total Aminoacids (TAA) occurred based on tissue and sex, with AC and MB of female and Gd of male showing higher contents (range 47.8 -60.2 g/kg ww). Glycine and glutamic acid were the most abundant. Polyunsaturated (PUFA) was the major class of fatty acids and Arachidonic and Eicosapentaenoic (EPA) acids were the predominant PUFA. n-3 PUFA showed higher content in Gd, AC and RT indicating a higher quality. A favorable n-3/n-6 in the range 1.04-1.67 was observed. PAHs showed values ranged from 23 to 207 µg/kg ww with the highest levels in Gd-AC tissues and the lower in BW. Benzo[a]Pyrene, the most toxic compound, was detected in all tissues, of both sexes, at levels of 1.5-18 µg/Kg ww.

Conclusion

All tissues of H. polii, although with differences among them, are valuable food and can contribute for a healthy diet. Excess Cancer risk (CR) values for Gd and AC tissues, were above the considerable CR threshold of one in ten thousand established by USEPA, for high ingestion rate of these seafood.

An integrated approach using chemical ecological risk assessment and multi-integrated biomarker indexes approach to assess pollution: A case study of Ruditapes philippinarum in four bays on the Shandong Peninsula in China

Considering the ecological risks of polycyclic aromatic hydrocarbons (PAHs) to the marine environment, it is urgent to find scientific and effective monitoring methods. In this study, an integrated approach combining chemical ecological risk assessment and multi-integrated biomarker indexes approach was used to assess the marine environment. Samples included seawater, sediments, and clam Ruditapes philippinarum were collected from four bays on the Shandong Peninsula, China in the four seasons of 2019. The concentrations, composition, potential sources, and ecological risk of PAHs were investigated in seawater and sediments. Risk quotient (RQ) and sediment quality guidelines (SQGs) were calculated to assess the ecological risks of PAHs in seawater and sediment, respectively. And then, clam Ruditapes philippinarum's multi-level biological response, including its ethoxyresorufin-O-deethylase (EROD), glutathione S-transferase (GST), superoxide dismutase (SOD), lipid peroxidation (LPO), and acetylcholinesterase (AChE) were investigated in-depth, by which multi-integrated biomarker indexes approach were calculated to evaluate marine environmental quality. Taken together, the results showed that the concentration of PAHs was in good agreement with the response of biomarkers, and the usefulness of the combined use of chemical ecological risk assessment and integrated biomarker indexes to assess PAHs pollution was verified.

Polycyclic aromatic hydrocarbons in seawater, surface sediment, and marine organisms of Haizhou Bay in Yellow Sea, China: Distribution, source apportionment, and health risk assessment

The pollution status of polycyclic aromatic hydrocarbons (PAHs) in seawater, surface sediment, and marine organisms was investigated in Haizhou Bay, which is a traditional marine fish farming region in China. The total concentrations of PAHs in seawater, surface sediment, and marine organisms were 12.4-40.3 ng/L (average 24.8 ng/L), 183.2-496.6 ng/g (average 293.5 ng/g), and 228.1-679.9 ng/g (average 392.6 ng/g), respectively. Source analysis results showed that the PAH sources for seawater and marine organisms were coal and biomass combustion (66.53%), petroleum (28.94%), and traffic (4.52%), while those for the surface sediment were traffic (48.14%), coal and biomass combustion (40.56%). The lifetime cancer risk increment (ILCR) values of marine organisms in the Haizhou Bay were less than 10^-6, indicating no carcinogenic risk. In the future, this study can be used as a reference to understand the distribution and interrelation of PAHs in other semi-enclosed bays in the world.

Gene expression and functional analysis of different heat shock protein (HSPs) in Ruditapes philippinarum under BaP stress

Heat shock proteins (HSPs) are a class of highly conserved proteins which can protect cells against various types of stress. However, little information on the mechanism involved in the organic contaminants stress response of HSPs is available, especially in marine invertebrates. The present study was conducted to evaluate the responses of HSPs in clams (Ruditapes philippinarum) under Benzo[a] pyrene (BaP) exposure. The clams were exposed to BaP (concentrations: 0, 0.1, 1, 10 μg/L) for 15 days. 6 HSPs mRNA were classified, and the results of tissue distribution indicated that 4 HSPs gene expressed most in the digestive glands. The transcription level of 6 HSPs (HSP22-1, HSP22-2, HSP40A, HSP60, HSP70, HSP90) genes and the aryl hydrocarbon receptor signaling pathway-related genes, and detoxification system-related enzymes activities were analyzed at 0, 1, 3, 6, 10 and 15 days. The activities of phase II detoxification metabolic enzymes and signaling pathway related genes in clams were severely affected by BaP stress and presented significant difference. Our result suggested that HSPs were produced in the presence of BaP and participated in the process of detoxification metabolism to a certain extent. Additionally, the transcription of HSP40A gene may be used as a potential biomarker of BaP exposure due to its evident concentration- and time-dependent expression pattern. Overall, the study investigated the classification of HSPs in R. philippinarum, provided information about the expression profiles of various HSPs after BaP exposure and broadened the understanding mechanism of HSPs in detoxification defense system under PAHs stress in mollusks.

Polycyclic aromatic hydrocarbons in sediments and shellfish from Todos os Santos bay, Brazil

The present study evaluated the occurrence of 24 Polycyclic Aromatic Hydrocarbons (PAHs) in sediments and shellfish (Anomalocardia flexuosa, Crassostrea rhizophorae, and Mytella guyanensis) of Todos os Santos bay (BTS, Brazil). Total PAHs levels ranged from 89 to 921 ng g^-1 dry weight (d.w.) in sediments, and from 66 to 505 ng g^-1 d.w. in shellfish, signalizing that BTS was moderately contaminated by PAHs, mostly from pyrogenic activities. The bioaccumulation factor (BAF) of total PAHs ranged from 0.20 to 2.9 and did not show a clear trend among the studied species. BAFs of high molecular weight compounds were higher for A. flexuosa (specie found buried in fine sediment), while those of low molecular weight compounds were higher for C. rhizophorae (specie found in the roots of mangrove trees). High concentrations of PAHs, especially benzo[a]pyrene and dibenzo[a,h]anthracene, suggest that contamination compromises shellfish quality and raise concern about seafood consumption safety.

Spatiotemporal occurrence, sources and risk assessment of polycyclic aromatic hydrocarbons in a typical mariculture ecosystem

The spatiotemporal variations, influencing factors and potential sources, as well as the ecological/health risks of polycyclic aromatic hydrocarbons (PAHs) were systematically investigated in seawater, sediment, and fish from Xiangshan Bay, China, one of the most important and oldest domestic marine aquaculture bases. The average concentrations of Σ_PAHs in seawater, sediment and fish were 150 ± 70.0 ng/L, 276 ± 271 μg/kg (dry weight, dw), and 434 ± 151 μg/kg (dw), respectively. Naphthalene, phenanthrene, fluoranthene, benzo(b)fluoranthene and pyrene were the dominant contaminants in all samples. The highest PAH concentrations in the seawater and sediment samples occurred in the inner bay where the mariculture and industry are clustered. Seasonal differences were observed in the seawater samples but not in the sediment samples. Among all 15 fish species, large yellow croaker (Larimichthys crocea) (775 μg/kg (dw)), red drum (Sciaenops ocellatus) (749 μg/kg (dw)), and flathead grey mullet (Mugil cephalus) (637 μg/kg (dw)) had relatively high PAH accumulation concentrations in muscle tissue. According to the molecular diagnostic ratio method, the PAHs in seawater mainly originated from a mixed source of petroleum and combustion, whereas biomass/coal combustion sources were identified for sediment. The results obtained from the risk quotient (for seawater), sediment quality guidelines and toxic equivalence quotients (for seawater and sediment) methods showed that the ecological risks posed by PAHs were generally at a low to moderate level. Potentially toxic effects existed from PAH-contaminated fish consumption, and the resulting potential carcinogenic risk was also slightly higher than the recommended guidelines (10^-6).

PAH residue and consumption risk assessment in four commonly consumed wild marine fishes from Zhoushan Archipelago, East China Sea

The concentration, constitution, distribution, possible sources, and associated consumption risks of polycyclic aromatic hydrocarbons (PAHs) in four marine fishes in the Zhoushan Archipelago were investigated. The concentrations of PAHs in the edible muscle of these four fishes ranged from 34.7 to 108 ng/g wet weight. Four-ring and six-ring PAH congeners constitute the most and least percentages of the total PAHs, respectively. The highest PAH concentrations were found in Mugil cephalus, followed by Sebastiscus marmoratus, Lateolabrax maculatus, and Collichthys lucidus. The highest PAH concentrations were found at the sampling island Liuheng, followed by Gouqi, Qushan, Dongji, and Zhujiajian. PAH concentrations in wet weight were remarkably different among these four fish species but not among different locations. High-molecular-weight congeners predominated the PAH composition pattern in most of the samples. Results showed that the consumption of M. cephalus might have potential carcinogenic risk. This study provided baseline data on PAH concentrations in seafood and consequent human consumption risk.

Polycyclic aromatic hydrocarbons (PAHs), arsenic, chromium and lead in warty crab (Eriphia verrucosa): occurrence and risk assessment

This study assesses the PAH and heavy metal levels in muscle of warty crabs (Eriphia verrucosa), from the northern coast of the Campania region improving the data on toxic contaminants in this crustacean. The results showed a minimal PAH contamination; the mean concentrations were as follows: 0.2, 1.6 and 1.7 μg kg-1 wet weight (ww) for BaP, PAH4 and PAH6, respectively. Regarding the levels of the two PAHs not included in the European regulations, the BkF mean concentration was 0.1 μg kg-1 ww, while DahA was detected only in 10.7% of samples. Pb and Cr were also detected at low levels with mean values of 0.068 and 0.468 mg kg-1 ww, respectively; instead, high As levels, with a mean value of 5.021 mg kg-1 ww, were found. Considering the EWIs and the ILCRs calculated in this study, the PAH, Pb and Cr contamination levels found in the edible part of the crabs resulted safe for human consumption. Contrariwise, the ILCR calculated for the As exceeded the acceptable level of cancer risk, although the calculation did not refer to the inorganic form which is the only one recognized as carcinogenic. Hence, this study shows that warty crabs can accumulate environmental contaminants in their muscle tissue representing an important route of exposure to these toxics for the local population that regularly consumes them. This finding highlights the importance of monitoring the presence of these pollutants in crabs and in general in all fish and seafood in order to ensure food safety for consumers.

Pollution level and health risk assessment of polycyclic aromatic hydrocarbons in marine fish from two coastal regions, the South China Sea

Marine fishes are consumed in large quantities by humans as nutritious food. However, the intake of fish polluted by chemicals may pose a severe threat to human health. This study measured the concentrations of 16 priority polycyclic aromatic hydrocarbons (PAHs) in the muscles of 22 species of marine fish from two coastal regions, i.e., Tanmen and Zhuhai, identified the source of PAHs, and assessed the human health risk by dietary exposure. Total PAH (Σ₁₆PAHs) levels in Tanmen and Zhuhai fish were in the range of 24.29-684.83 ng g^-1 dry weight (dw) and 13.74-42.59 ng g^-1 dw, averaging 161.46 ng g^-1 dw and 31.21 ng g^-1 dw, respectively. Compared with other regions in the world, PAH concentrations in Tanmen fish were at median levels, and Zhuhai fish were at low levels. Low molecular weight PAHs (with 2- and 3-rings) were the predominant compounds detected. Molecular diagnostic ratios suggested that PAHs in Tanmen mainly originated from petrogenic sources such as vessel operations or tanker accidents, while Zhuhai fish were mainly polluted by pyrolytic sources such as combustion of coal and wood. The human health risk assessment results indicated that the risk of PAH intake via fish consumption from Zhuhai was negligible, while five species from Tanmen may pose potential health risks to local residents.

Pollution status of polycyclic aromatic hydrocarbons in surface sediments off the Jiangsu coastal zone, East China: A case study of Rudong

In the current study, 16 congeners of PAHs were measured in 32 surface sediment samples to determine their pollution status in the Jiangsu coastal zone, East China. The total concentrations of the 16 PAHs ranged from 2.2 to 46.6 ng g^-1 with an average of 8.36 ng g^-1 in surface sediments and were significantly lower than those of PAHs in other coastal areas of China. The spatial distribution of PAHs revealed an increasing trend from nearshore to offshore, controlled by the regional sedimentary dynamic environment. Diagnostic ratios and positive matrix factorization demonstrated that petroleum, industries, biomass and coal combustion, and marine and vehicular traffic sources contributed to 28.9%, 25.5%, 24.7%, and 20.9% of the total PAHs, respectively. Risk assessment suggested that the carcinogenic risks were <1 × 10^-4 for all age groups in the area, indicating that long-term seafood consumption does not pose a significant cancer risk in this area.

Fate and Occurrence of Polycyclic Aromatic Hydrocarbons and Their Derivatives in Water and Sediment from Songhua River, Northeast China

The Songhua River is one of the most populated and oldest industrial areas in Northeast China. To understand the sources and distribution of polycyclic aromatic hydrocarbons and their derivatives, such as 16 priority (PAHs), 33 methylated (Me-PAHs), and 12 nitrated (NPAHs) in river water and sediment, were noticed. The concentrations of ∑PAHs, ∑Me-PAHs, and ∑NPAHs in river water scaled from 135 to 563, 9.36 to 711, and 1.26 to 64.7 ng L−1, with mean values of 286, 310, and 17.9 ng L−1, and those in sediments were from 35.8 to 2000 ng g−1, 0.62 to 394 ng g−1, and 0.28 to 176 ng g−1 (dry weight) with mean values of 283, 103, and 21.7 ng g−1. The compositions proved that two-ring and three-ring compounds of PAHs, NPAHs, and four-ring, six-ring of Me-PAHs were prevalent in water samples; in contrast, four-ring dominated in sediments. Principal components analysis (PCA) and diagnostic ratios confirmed that pollutant source was mixed petrogenic and pyrogenic origin. The fugacity fraction (ƒƒ) was also calculated to explain the trend of sediment–water exchange, high ƒƒ values found in summer, for most HMW PAHs and Me-PAHs that these substances acted as a secondary source of emissions from sediment to water. The risk assessment for water was categorized as high.