Variation Of Polycyclic Aromatic Hydrocarbons Research Articles

Disturbance of OH-PAH metabolites in urine induced by single PAH lab exposure.

Due to the high exposure toxicity and individual variability of polycyclic aromatic hydrocarbons (PAHs), it is difficult to accurately characterize the actual exposure of exposed individuals through external exposure detection. In this study, the monohydroxyl metabolites of naphthalene, phenanthrene, pyrene, and 9-fluorenone were identified in the urine of low-dose PAH-exposed individuals based on ultra-performance liquid chromatography-high-resolution mass spectrometry (UPLC-HRMS), and their concentrations were monitored for 15 consecutive days after exposure. The results showed that the metabolite concentrations of naphthalene, phenanthrene, and pyrene were basically the same, and all of them reached the maximum value at day 8. In contrast, the metabolite of 9-fluorenone reached its maximum value on day 2. This study showed that the four metabolites were strongly correlated with their parent PAH exposure, with a wide detection window, and their assays were specific, sensitive, and reliable, while the sampling difficulty was low, so the four hydroxylated PAHs may be potential low-dose biomarkers of PAH internal exposure. This study will provide methodological and data support for further health risk studies involving internal exposure to organic pollutants such as PAHs.

Preface

We are pleased to provide you with the proceedings of 2022 4th International Conference on Resources and Environment Sciences (ICRES 2022).The conference was expected to be held during June 10-12, 2022 in Bangkok, Thailand, while the situation of COVID-19 pandemic is unpredictable and unstable. Most of conference participants could not travel to attend the conference venue to do oral presentations. Taking all conditions into consideration, conference committee decided to change physical conference into virtual conference. It was held online by ZOOM application successfully during the same date.The conference was highlighted by four outstanding Keynote Speakers and two invited speakers. Keynote speakers include Prof. Kaimin Shih, The University of Hong Kong, China with his topic “Metal Stabilization and Resource Recovery Examples in Urban Environment”; Prof. Nur Islami, University of Riau, Indonesia who presented a talk on “An Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”; Prof. Danny Sutanto, University of Wollongong, Australia who shared a speech on “Solid-State Transformer for Smart Power Grid Applications”; Assoc. Prof. Phebe Ding, Universiti Putra Malaysia, Malaysia who presented a talk about “Role of Postharvest Technology in Producing Quality Fresh Horticultural Produces”. Additionally, two excellent invited speakers, Assoc. Prof. Chunrong Jia from University of Memphis, Tennessee, USA with speech title “Apportioning variability of polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and Assoc. Prof. Farhad Shahnia from Murdoch University, Australia with speech title “Recent and Future Research on Microgrid Clusters”.Each normal oral presenter had about 12 Minutes of Presentation and 3 Minutes of Question and Answer. Conference was organized in 5 sessions with various topics: Environmental Management, Waste Utilization and Sustainable Development, Wastewater Treatment, Water Analysis and Hydraulic Engineering, Renewable Energy Technology, Chemical Engineering and Fluid Mechanics, Resources and Environmental Science & Sustainable Development, Energy and Chemical Engineering.All accepted papers presented at the ICRES 2022 were included in this volume, which contained three chapters with topics: (1) Environmental Pollution and Control (2) Waste Management and Utilization (3) Clean Energy and Technology. All papers were subjected to peer-review by conference committee members and international reviewers. The papers were selected based on high quality and high relevancy to the conference scope.We would like to express our sincere gratitude to organizing committee and the volunteers who have dedicated their time and efforts in planning, promoting, and helping the conference. We hope that the readers would gain some valuable knowledge from this effort.List of Committees, Statement of Peer Review are available in this Pdf.

Decadal Variation of Polycyclic Aromatic Hydrocarbons (PAHs) in an Area Contaminated by Coal Gangue Dump: Emphasis on Concentration, Profile, Source and Carcinogenic Risk

Polycyclic aromatic hydrocarbons (PAHs) are recognized as carcinogens that pose a severe threat to human health. Research on the temporal variation of PAHs was confined to monthly and seasonal investigations, and a longer timescale study remained inadequate until recently. Therefore, this study focuses on the decadal variation of PAHs in environmental media contaminated by a coal gangue dump in the Jiulong Coal Mine, Fengfeng, China. The results show that the total concentrations of PAHs have sharply declined compared to the past. The result of the paired-sample t-test indicates that several individual PAHs have obviously changed in concentration with statistical significance (p < 0.05). Moreover, proportions of medium-molecule weight PAHs increase with statistical significance (p < 0.01) when compared to the past. Various diagnostic ratios suggest that PAHs in previous samples are mainly derived from weathering products of coal gangue and vehicle exhaust, while PAHs in the present samples are dominated by those originating from pyrogenic sources. Calculation of incremental lifetime cancer risks (ILCRs) indicates high carcinogenic risk despite a considerable decrease in ILCR values by 2 to 3 orders of magnitude. It shows that recent measurements conducted by the local government do weaken the contamination of coal gangue dumps, but more attention to pyrogenic PAHs is necessary.

Heavy metal background levels and pollution temporal trend assessment within the marine sediments facing a brownfield area (Gulf of Pozzuoli, Southern Italy)

In this study, site-specific natural background levels (NBLs) were determined for 18 elements (Al, As, Be, Cd, Co, Cu, Cr, Fe, Hg, K, Mn, Mo, Ni, Pb, Tl, U, V, and Zn) in two sediment cores collected offshore the Bagnoli-Coroglio brownfield site (Gulf of Pozzuoli, southern Italy) to accurately assess the degree of contamination and the historical trends in Heavy Metals (HMs) enrichment. This objective was pursued taking in account the high temporal and spatial variability of the geochemical properties of the area due to the local geothermal activity. Moreover, the temporal variation of Polycyclic Aromatic Hydrocarbons (PAHs) was investigated.226Ra was used as an extraordinary marker to confirm 210Pb dating. It especially allowed defining the geochronological framework of the sediment core closer the brownfield up to around 1500, providing compelling support to correlate the investigated elements’ occurrences with natural geogenic dynamic. Sediment samples were accurately dated and analyzed for chemical and particle size composition. The contamination factor (Cf) and the pollution load index (PLI) showed very high enrichment of Cd, Cu, Hg, Pb, and Zn. The contamination profiles of HMs and PAHs follow the same pattern in both sediment cores, increasing from deep to upper layers. The highest contamination levels for HMs and PAHs were observed between 10 and 30 cm, corresponding to the periods of most intense industrial activity. Decreasing trends of pollutants were observed in the surface layers (0–10 cm), probably affected by a natural attenuation process due to the cessation of industrial activities.

Spatial and seasonal variation and sources of deposition fluxes of polycyclic aromatic hydrocarbons (PAHs) in Shanghai.

Spatial and temporal variations of polycyclic aromatic hydrocarbons (PAHs) deposition fluxes and sources may significantly facilitate risk evaluation and pollution control of super megacity in China. A study on PAHs of wet and dry deposition in Shanghai was conducted from January to December of 2019. Seventeen sampling sites located in four functional areas were set, including the Baoshan iron and steel industry area (BS), Jinshan petrochemical industry area (JS), city center (CC), and Chongming agricultural area (CM). A total of 15 PAHs were determined by gas chromatography-mass spectrometry (GC-MS, Agilent 7890A/5975C). PAHs atmospheric deposition flux in winter was highest (3.12 ± 1.98μg/(m2·day), mostly attributed to local emissions accumulation under adverse meteorological diffusion conditions, as well as pollutants transport from northern China during heating season. PAHs deposition fluxes in industrial area (BS and JS) were 3.75 ± 4.08μg/(m2·day) and 3.18 ± 3.62μg/(m2·day) respectively, which were greater than those in CC and CM, accounting for 1.91 ± 1.06μg/(m2·day) and 1.41 ± 0.61μg/(m2·day) respectively. Proportional composition and isomer ratios of PAHs indicated that the PAHs deposition in winter and spring samples were more homogeneous, whereas those of summer and autumn seemed to be more variable and dispersed. Positive matrix factorization model were employed to identify the potential sources of PAHs in specific functional areas. A dominance of contribution was attributed to coal combustion (46%) at BS, petroleum volatilization (48%) at JS, biomass burning (55%) at CM, and vehicle emission (49%) at CC. This study highlighted that local urbanization and industrialization have a significant contribution to PAHs deposition to specific functional regions in Shanghai.

Multimedia distribution of polycyclic aromatic hydrocarbons in the Wang Lake Wetland, China

The Wang Lake Wetland is a highly valued area that is protected due to its high biodiversity. The wetland has a complicated hydrological regime and is subject to frequent human disturbance. We hypothesize that fluctuating hydrology and human activities have varied contributions to the temporal and spatial variations of polycyclic aromatic hydrocarbons (PAHs) in the wetland. Soil (SS), sediment (SD), and water, to acquire dissolved phase (DP) and suspended particulate matter (SPM), samples were collected from eight locations during low- and high-flow periods to elucidate multimedia phase distribution and transport of PAHs. Following the onset of the rainy season, the concentration of SPM-associated PAHs increased significantly, while the DP PAHs remained stable. Individual PAH ratios showed that, although pyrogenic sources are common, petrogenic derived compounds are the main source of PAHs in the Wang Lake Wetland. During the high-flow period, the empirical values for logarithms of the organic carbon-normalized partition coefficients (log KOC) of individual PAH-congeners were lower than the corresponding field-observed log KOC values from the SPM-DP and SD-DP systems, reflecting the complexity in evaluating multi-phase PAH partitioning. During the high-flow period, temperature-driven changes may have changed the sediment from a sink to a source for some high molecular weight PAHs. It was determined that human activities governed the PAH loading in the low-flow period, whereas during high-flow conditions, increased rainfall, higher temperatures, and fishery activity are the main factors controlling PAH input to the Wang Lake Wetland.

Polycyclic Aromatic Hydrocarbons in the Marine Atmosphere from the Western Pacific to the Southern Ocean: Spatial Variability, Gas/Particle Partitioning, and Source Apportionment.

The spatial variability of polycyclic aromatic hydrocarbons (PAHs) in the marine atmosphere contributes to the understanding of the global sources, fate, and impact of this contaminant. Few studies conducted to measure PAHs in the oceanic atmosphere have covered a large scale, especially in the Southern Ocean. In this study, high-volume air samples were taken along a cross-section from China to Antarctica and analyzed for gaseous and particulate PAHs. The data revealed the spatial distribution, gas-particle partitioning, and source contributions of PAHs in the Pacific, Indian, and Southern Oceans. The median concentration (gaseous + particulate) of ∑24PAHs was 3900 pg/m3 in the Pacific Ocean, 2000 pg/m3 in the Indian Ocean, and 1200 pg/m3 in the Southern Ocean. A clear latitudinal gradient was observed for airborne PAHs from the western Pacific to the Southern Ocean. Back trajectories (BTs) analysis showed that air masses predominantly originated from populated land had significantly higher concentrations of PAHs than those from the oceans or Antarctic continents/islands. The air mass origins and temperature have significant influences on the gas-particle partitioning of PAHs. Source analysis by positive matrix factorization (PMF) showed that the highest contribution to PAHs was from coal combustion emissions (52%), followed by engine combustion emissions (27%) and wood combustion emissions (21%). A higher contribution of PAHs from wood combustion was found in the eastern coastal region of Australia. In contrast, engine combustion emissions primarily influenced the sites in Southeast Asia.

Seasonal Variations of Polycyclic Aromatic Hydrocarbons in the Muscle Tissue of Silurus triostegus Heckel, 1843 from Derbendikhan Reservoir

Derbendikhan reservoir is located on the southeast of Sulaimani city 35° 6' 35" N, 45° 41' 20" E, it is the second largest reservoir in the Iraqi Kurdistan region at an altitude of 485 m above sea level. It was formed when the dam was constructed in1956–1961. The area is about 114.30 km2 with the maximum depth of 75.0 m. Silurus triostegus is one of twenty genera of fish that are endemic to Derbendikhan reservoir, Seasonal sampling for 64 samples of fish for 11 sites was carried out from November 2018 to August 2019, Fishing was performed with gill nets of 18, 25, 33, 40, and 55 mm inner mesh sizes. The goal of this research is to determine the level of PAHs in, fish muscle of Silurus triostegus, because fish as an important food source for man and it’s the primary indicator of the toxification of streams and lakes, on the other hand, PAH will cause many health problems including cancer, in addition, this information may be used as a database for any environmental modeling in the future, this study was carried out. Results indicate increasing in PAH in the spring season, although, as a result of fishing activities using old boats and ships at a high rate, in addition to the changes of water temperature in different season. PAH in the muscle of fish (0.098–1.271 μg/g) were above the WHO maximum permissible limit of 0.001 μg/g. The main conclusion is that the fish muscle contains high amounts of PAHs through bioaccumulation and biomagnifications. Finally, the lake needs immediate attention to reduce improper waste disposal and improve on measures against indiscriminate dumping of petroleum products and domestic waste in the water, which are the major sources of petrogenic and pyrogenic PAHs should be minimized, and the treatment of the sewage before its discharge into the reservoir.

Evaluation of distribution characteristics and health risk of polycyclic aromatic hydrocarbons in sediments: From the perspective of land–ocean coordination

Land-ocean coordinated management is an important wisdom for environmental protection and pollution prevention of marine and river systems. Taking Liao River and Estuarine as an example, the pollution characteristics, temporal and spatial distribution and change features of Polycyclic Aromatic Hydrocarbons (PAHs) in sediments in recent 20 years were studied from two different analysis perspectives of land and ocean. The research showed that the pollution of PAHs in the sediments of Liao River and Estuarine was not optimistic. The concentration of Σ16PAHs was 48–28,000 ng/g. The carcinogenic risk to humans shouldn't be ignored, which could cause the loss of life expectancy 0.03–4.2 years. The traceability analysis showed that the use and combustion of fossil fuels were the main sources of PAHs. In addition, the leakage of oil during the intensive transportation of ships in coastal waters might also contribute to PAHs. The concentrations of PAHs had obvious temporal and spatial distribution characteristics. Spatially, estuaries < tributaries < main streams; temporally, wet season < normal season < dry season in Liao River. Whereas, the variation of PAHs in estuarine sediments was slight. In the past 20 years, the concentration of PAHs in Liao River had increased first and then decreased, reaching maximum in 2010; However, the concentration of PAHs seldom decreased in estuarine sediments, in which showed a more serious situation of PAHs pollution control.

Spatial distribution and temporal variation of polycyclic aromatic hydrocarbons in runoff and surface water

This study aims to investigate the spatial distribution of and temporal variation in the phase distribution, emission sources, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in runoff and in surface water mixed with runoff discharge. The samples were collected at semi-rural, residential, and industrial sites in Ulsan, South Korea, from April to October 2016. The industrial site had the highest PAH concentrations in the runoff and surface water due to the higher PAH levels found in the surrounding environmental media. The PAH phase distributions were relatively similar between the sampling sites, with dissolved PAHs (2- to 4-ring species) dominant. In July, the PAHs in the surface water were more commonly found in the dissolved phase due to the higher water temperature and dissolved organic carbon concentration. The emission sources for the PAHs were identified using principal component analysis (PCA), a dimension reduction technique, and the k-nearest neighbor (KNN) classifier, a supervised learning algorithm. It was determined that the PAHs in the runoff and surface water were likely to share similar petrogenic and pyrolysis sources for most of the sampling periods. The ecological risk of the surface water was 1.5–4.5 times lower after being mixed with runoff water, mainly due to dilution effects. The ecological risk for surface water was highest in July because of the higher PAH concentrations. This study contributes to the understanding of PAHs in runoff and in surface water affected by runoff discharge.

Polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons in five East Asian cities: Seasonal characteristics, health risks, and yearly variations

Total suspended particulate matter and fine particulate matter were collected in five East Asian cities (Sapporo, Sagamihara, Kirishima, Shenyang, and Vladivostok) during warm and cold periods from 2017 to 2018. Nine polycyclic aromatic hydrocarbons (PAHs) and three nitro-polycyclic aromatic hydrocarbons (NPAHs) were detected by high-performance liquid chromatography with a fluorescence detector. The average concentrations of ∑PAHs and ∑NPAHs differed significantly both temporally and spatially and were the lowest in Kirishima during the warm period (∑PAHs: 0.11 ± 0.06 ng m−3; ∑NPAHs: 1.23 ± 0.96 pg m−3) and the highest in Shenyang during the cold period (∑PAHs: 49.7 ± 21.8 ng m−3; ∑NPAHs: 357 ± 180 pg m−3). The average total benzo[a]pyrene-equivalent concentrations were also higher in Shenyang and Vladivostok than in Japanese cities. According to the results of source apportionment, traffic emissions impacted these cities in both the warm and cold periods, whereas coal combustion-generated effects were obvious in Shenyang and Vladivostok during the cold period. Furthermore, PAHs and NPAHs originating from the Asian continent, including Shenyang and Vladivostok, exerted some influence on Japanese cities, especially in the cold period. Compared to Japanese cities and Vladivostok, yearly variations in ∑PAHs and 1-nitropyrene in Shenyang showed that their concentrations were considerably lower than those reported in past studies, indicating the positive effects of air pollutant control policies in China. These results not only describe the current characteristics and yearly variations of PAHs and NPAHs in typical urban cities in East Asia but also, more importantly, reveal that the effects of the East Asian monsoon play an important role in the analysis of atmospheric behaviours of PAHs and NPAHs. Furthermore, this study supports the role of multinational cooperation to promote air pollution control in East Asia.

Levels, distributions, and seasonal variations of polycyclic aromatic hydrocarbons (PAHs) in ambient air and pine components.

Pine tree (Pinus pinea) components have been used as passive air samples for determining atmospheric polycyclic aromatic hydrocarbon (PAH) concentrations. Our results indicated that pine needles and branches were found to be statistically successful in describing the ambient air. Monthly pine needles, branches (1- and 2-year-old) and ambient air samples were collected for 1 year to identify molecular distributions and temporal concentrations of PAHs in a suburban-industrial area. Annual average Σ14PAH concentrations for pine needles, 1- and 2-year-old branches, and ambient air were 756 ± 232ng/g DW, 685 ± 350ng/g DW, 587 ± 361ng/g DW, and 28.29 ± 32.33ng/m3, respectively. The order of average Σ14PAH concentrations in the pine tree components was determined as needle > 1-year-old branch > 2-year-old branch. In general, concentrations increased with the rise in the surface area of tree components. In the samples, 3- and 4-ring PAHs were dominant compounds in the ambient air, pine needles, and branches. The annual total fraction of 3- and 4-ring PAHs in the air was 98.5%, while the fraction of 5- and 6-ring PAHs was 1.5%. On the other hand, 3- and 4-ring PAHs in pine needles and branches were 30% or more. The fraction and level of PAHs change with the season. Although needle samples did not show any seasonal trend, PAH levels in other tree components changed with the air temperature. Generally, lower values were observed in warmer seasons in the branch samples. Similarly, ambient air PAH concentrations were higher in the winter season due to heating and adverse meteorological conditions.

Seasonal variations of polycyclic aromatic hydrocarbons in coastal sediments of a marine resource hot spot: the case of pars special economic energy zone, Iran.

Polycyclic aromatic hydrocarbons (PAHs) are an important group of compounds of major environmental concern, which are in the class of persistent organic pollutants. Therefore, the key purpose of this research was to analyze seasonal fluctuations and to determine the probability of polycyclic aromatic hydrocarbons in coastal sediments of the Iranian Marine Resource Center based on the evaluation of 16 US-EPA important PAH compounds. These compounds have been collected from intertidal sediments located in the marine resources of southern Iran in different seasons. These samples of the surficial sediment were collected at the PSEEZ area using a stainless steel grab sampler in four seasons, from depths between 0.5 and 30m. Surface sediment samples were removed by spoons and carefully placed in an aluminum foil; they were taken to the laboratory on ice and held at 20° C until their study. After extraction, by using a rotary evaporator apparatus, samples were condensed. The assay was added to roughly 2g of activated copper flasks in the refrigerator for 36h for desulfurization. Among different seasons, the highest concentration was observed in winter, with a mean of 281.3ngg-1. According to ecological risk assessment (concentrations of possible effects, low effect range, degree of threshold effects, and median effect range), PAH risks in surface sediments of PSEEZ were lower than the threshold results levels (TEL), possible effects levels (PEL), low range of effects (ERL), and median range of effects (ERM), indicating that a biological effect would rarely occur. The dry weight scale of the concentration of ∑PAHs ranges from 145.7 to 348.42ngg-1 with a mean quantity of 260.52ngg-1. Therefore, according to the amount of ∑PAH concentration, the sediments in the PSEEZ area indicated moderate to heavy pollutions. In this way, the sedimentary surface ecosystems of the Persian Gulf were considered as moderately polluted compared with other ecosystems worldwide. Our study highlighted some of the research gaps in PAH contamination studies and the level of PAH contamination. Therefore, this study will provide a scientific background, planning, and policies for PAH pollution control and environmental protection in Iran and similar regions around the world.

The contributions of an airport and related road network to Pseudevernia furfuracea bioaccumulation of trace elements and polycyclic aromatic hydrocarbons

The use of a high-density lichen transplant network together with quantitative wind relationships (WQRs) made it possible to evaluate the influence of an airport and surrounding road network on the spatial variation of polycyclic aromatic hydrocarbons (PAHs) and trace elements at both the local and whole study area scale. WQRs clearly showed that the parking/idling/taxiing area (PIT), but not the landing/take-off zones (LTZs), as well as the north/north-east part of the road network were contributors at the whole study area scale to the spatial variation of elements like Ni, Mo and V, i.e. those associated with ultrafine particles due to their involvement in anti-wear materials, and of total PAHs. In the case of an airport, such a result can have strong management implications. Traffic also affected the concentration of the prevailing volatile organic compounds. In contrast, LTZs and high traffic density values were correlated with peaks of Zn, Mo, Cu, Co, Mn, Ni, V, Al and Sb when associated with coarse particulate matter generated by deterioration of the landing gear, fuselage, wings, runway asphalt and brakes. The remarkable percentage of high-speed winds strongly affected both the spatial distribution of anthropogenic emissions and their atmospheric dilution, resulting in a rather low level of contamination. Our results suggest that biomonitoring can be much improved when matched with WQRs and that, in the event of high wind speeds, PAHs associated with the gas phase and fine/ultrafine particles are effective contamination tracers mainly at the whole study area scale whereas trace elements reveal contamination patterns at both scales.

RETRACTED: Matsunaka et al. Temporal Variations of Polycyclic Aromatic Hydrocarbons in the Seawater at Tsukumo Bay, Noto Peninsula, Japan, during 2014–2018. Int. J. Environ. Res. Public Health 2020, 17, 873

The journal retracts the article "Temporal Variations of Polycyclic Aromatic Hydrocarbons in the Seawater at Tsukumo Bay, Noto Peninsula, Japan, during 2014-2018" cited above [...].

SEASONAL VARIATION OF VOLATILE POLY AROMATIC HYDROCARBONS (PAHS) RELEASED FROM DIFFERENT SOURCES IN SOUTH CAIRO

Understanding the seasonal variations of polycyclic aromatic hydrocarbons (PAHs) concentrations in ambient air in urban/rural or industrial regions is important to the effective control of air pollution in these regions. Based on an approximately a year round dataset (from January to November 2014), a total of 48 atmospheric samples were collected by high volume active air sampler over one year seasonal monitoring in order to assess the variation of PAHs concentrations in different areas through different seasons in south Al Tabbin area. The gaseous and particulate phases of PAHs were extracted and analyzed using GC/MS together. The total air concentrations of 16 USEPA PAHs in the study area ranged from 76.48 ± 19.44 µg/m3 to 26995.86 ± 2835.91 µg/m3, with an average concentration of 7085.08 ± 773.98 µg/m3. Seasonal trends of PAH concentrations were observed with high concentration in winter and low in summer where the average concentration of PAHs in winter were ~1.6 times higher than that in summer. This mainly attributed to meteorological conditions.

Seasonal foliar uptake of atmospheric polycyclic aromatic hydrocarbons by some local plants in a tropical metropolis in India

This study explored the interspecies and seasonal variation of polycyclic aromatic hydrocarbons (PAHs) in the extracted lipids of the leaves of seven local plants in an urban environment of Kolkata (22°33′N and 88°20′E), India. Based on the degree of toxicity and carcinogenicity (expressed in terms of their Benzo(a)pyrene equivalent (BaPeq) concentrations) the overall foliar-PAH accumulation during the study period (September 2018‒;August 2019) in the various plants showed the following order: Nerium oleander (80.96 ± 30.08 ng.gdw−1) > Mangifera indica (74.15 ± 20.34 ng.gdw−1) > Lantana aculeata (60.13 ± 21.71 ng.gdw−1) > Thevetia peruviana (40.97 ± 12.45 ng.gdw−1) > Ixora coccinea (38.11 ± 9.5 ng.gdw−1) > Murraya paniculata (37.1 ± 7.35 ng.gdw−1) > Polyalthia longifolia (25.72 ± 5.71 ng.gdw−1). The PAHs like phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene, benzo (b+k)fluoranthene, benzo(a)pyrene, benzo [ghi]perylene and indeno [1,2,3-cd]pyrene were predominant during the study period over the PAHs like naphthalene, acynaphthylene, acenaphthene, fluorine and dibenz [a,h]anthracene in the extracted lipids. The temperature-dependent partitioning of the PAHs onto leaf-surface and photo-degradation could have affected the availability of the PAHs. The foliar PAH accumulation varied seasonally as winter (December–February) > postmonsoon (September–November) > premonsoon (March–May) > monsoon (June–August). The leaf epicuticular wax determined the PAH uptake and storage, which in turn was affected by the temperature and solar radiation. In consistence with the idea of “nature-based solutions” for deteriorated air quality remediation in an urban environment, this study could be a promising initiative to build up cost-effective biological filters to combat the airborne pollutants and improve urban air quality.

Variations of Polycyclic Aromatic Hydrocarbons in Vegetable Oils During Seed Roasting Pre-Treatment

Seed roasting is a critical step for fragrant oil as it achieves the development of aroma and flavor, but also it is the way of polycyclic aromatic hydrocarbons and other harmful substances generated. In this study, for the purpose of mimic moderate roasting as well as powerful roasting condition, five oilseeds (peanut, sesame, sunflower, rapeseed and flaxseed) were submitted to roast at six selected temperatures (160 °C, 180 °C, 200 °C, 220 °C, 240 °C and 260 °C) for increasing time. The PAH levels in the five oils which obtained from corresponding roasted seed were quantified via GC-MS. The results showed that the concentrations and types of PAH substances in oils rapidly became more plentiful over seed roasting temperature and time, resulting an increase in total PAH concentrations, particular at temperature above 200 °C. The PAHs produced during the roasting of oilseeds may be mainly attributed to the lipid content and the degree of unsaturation (or P/S index) of the oilseeds. The higher lipid content in the oilseed, the easier it is to produce PAHs during seed roasting pretreatment. Oilseed with high polyunsaturated fatty acids tend to produce HPAH, on the contrary, low polyunsaturated fatty acids tend to produce LPAH.

Corrigendum: Temporal Variability of Polycyclic Aromatic Hydrocarbons in Deep-Sea Cephalopods of the Northern Gulf of Mexico

Corrigendum: Temporal Variability of Polycyclic Aromatic Hydrocarbons in Deep-Sea Cephalopods of the Northern Gulf of Mexico

Spatial and temporal variations of PAHs in surface sediments of estuarine and coast of CanGio wetland, Vietnam.

Surface sediments from estuarine and coast of CanGio wetland (CGW) of Hochiminh City, Vietnam, were investigated to identify the spatial and temporal variations of polycyclic aromatic hydrocarbons (PAHs). The total PAHs showed wide variation but similar to patterns observed (F = 0.901, p = 0.46) in LongTau (31 ± 77ng/g dry weight, n = 13), SoaiRap (53 ± 81, n = 4), ThiVai (60 ± 62, n = 10) estuaries, and coastal areas (112 ± 211, n = 9). A decreasing trend in the wet season (F = 8.8, p = 0.01) reflected that inland sources such as wastewater discharged and atmospherically transported contaminants contributed to PAHs in sediments. The risk posed by the PAHs in the coastal and estuarine areas of CGW is still negligible. The present study provides baseline data, which can be used for regular monitoring and future strategy of environmental protection for the study area.