Polycyclic Aromatic Hydrocarbons Levels In Sediments Research Articles

Temporal and spatial distribution of polycyclic aromatic hydrocarbons (PAHs) in the Danube River in Hungary

The Danube is a significant transboundary river on a global scale, with several tributaries. The effluents from industrial operations and wastewater treatment plants have an impact on the river's aquatic ecosystem. These discharges provide a significant threat to aquatic life by deteriorating the quality of water and sediment. Hence, a total of 16 Polycyclic Aromatic Hydrocarbons (PAHs) compounds were analyzed at six locations along the river, covering a period of 12 months. The objective was to explore the temporal and spatial fluctuations of these chemicals in both water and sediment. The study revealed a significant fluctuation in the concentration of PAHs in water throughout the year, with levels ranging from 224.8 ng/L during the summer to 365.8 ng/L during the winter. Similarly, the concentration of PAHs in sediment samples varied from 316.7 ng/g in dry weight during the summer to 422.9 ng/g in dry weight during the winter. According to the Europe Drinking Water Directive, the levels of PAHs exceeded the permitted limit of 100 ng/L, resulting in a 124.8% rise in summer and a 265.8% increase in winter. The results suggest that the potential human-caused sources of PAHs were mostly derived from pyrolytic and pyrogenic processes, with pyrogenic sources being more dominant. Assessment of sediment quality standards (SQGs) showed that the levels of PAHs in sediments were below the Effect Range Low (ERL), except for acenaphthylene (Acy) and fluorene (Fl) concentrations. This suggests that there could be occasional biological consequences. The cumulative Individual Lifetime Cancer Risk (ILCR) exceeds 1/104 for both adults and children in all sites.

Are the tourist beaches safe for swimming? A case study of health risks of polycyclic aromatic hydrocarbons (PAHs) in tourist beaches of Bushehr City.

The aims of the present research were to evaluate the health risk of long-term exposure to polycyclic aromatic hydrocarbons (PAHs) concerning the human, ecotoxicological risk for marine biota, and identify their possible sources. Surface sediment bioassay samples were collected from 15 stations of tourist beaches surrounding Bushehr City and analyzed using high performance liquid chromatography (HPLC). The results indicated the concentrations of ∑PAH ranged from 193.5 to 725.5ngg-1 with mean value of 351.1 ± 155.2ngg-1, which could be considered as moderate level of pollution. Measured levels of PAH in sediments were compared with sediment quality guidelines (SQGs), indicating low to medium ecotoxicological risk on marine organisms. Moreover, mean ERM quotient (M-ERM-Q) and mean PEL quotient (M-PEL-Q) were implemented, demonstrating potentially biological adverse effects. A preliminary evaluation of human health risk using incremental lifetime cancer risk (ILCR) and toxic equivalent quotient (TEQcarc) indicated that PAH-contaminated sediment in some stations of touristic beaches of Bushehr City would induce potential carcinogenic effects especially for children. Composition and diagnostic analysis indicated that PAHs originated from both pyrogenic and petrogenic, with higher portion of incomplete combustion PAHs.

Relationship between Polycyclic Aromatic Hydrocarbons in Sediments and Invertebrates of Natural and Artificial Stormwater Retention Ponds

Sediments and invertebrates were sampled from 9 stormwater retention ponds (SWRPs) and 11 natural, shallow lakes in Denmark. Samples were analyzed for 13 polycyclic aromatic hydrocarbons (PAHs). The SWRPs received urban and highway runoff from various types of drainage areas and the lakes were located in areas of various land uses. Comparing PAHs in the sediments of the SWRPs and the lakes, it was found that levels of total PAH were similar in the two aquatic systems, with median values of 0.94 and 0.63 mg·(kg·DM)−1 in sediments of SWRPs and lakes, respectively. However, the SWRP sediments tended to have higher concentrations of high-molecular-weight PAHs than the lakes. A similar pattern was seen for PAHs accumulated in invertebrates where the median of total PAH was 2.8 and 2.1 mg·(kg·DM)−1 for SWRPs and lakes, respectively. Principal component analysis on the PAH distribution in the sediments and invertebrates showed that ponds receiving highway runoff clustered with lakes in forests and farmland. The same was the case for some of the ponds receiving runoff from residential areas. Overall, results showed that sediment PAH levels in all SWRPs receiving runoff from highways were similar to the levels found in some of the investigated natural, shallow lakes, as were the sediment PAH levels from some of the residential SWRPs. Furthermore, there was no systematic trend that one type of water body exceeded environmental quality standards (EQS) values more often than others. Together this indicates that at least some SWRPs can sustain an invertebrate ecosystem without the organisms experiencing higher bioaccumulation of PAHs then what is the case in shallow lakes of the same region.

Polycyclic aromatic hydrocarbons (PAHs) in mussels (Modiolus capax) from sites with increasing anthropogenic impact in La Paz Bay, Gulf of California

The composition, distribution and source of 16 polycyclic aromatic hydrocarbons (PAHs) in surface sediments and tissues of the mussel Modiolus capax from three sites with increasing anthropogenic impact in La Paz Bay on the Gulf of California, were determined. Levels of total PAHs in sediments (18.9-94.5 ng/g dw) were below the effect range low for marine sediments at all sites. PAHs in mussels (147.01-271.09) were higher than in sediments and similar to mussels from other moderately contaminated sites. The origin of PAHs was predominantly petrogenic, attributed to port activities and a thermoelectric plant. The mussels of Las Pacas and Pichilingue showed the lowest condition indexes and some organisms with the presence of benzo(a)pyrene in their tissues, which is among the most toxic hydrocarbons and may represent a risk to human health. However, this study only represents a baseline for future studies, which are necessary to dismiss risks to human health and the ecosystem.

Occurrence, sources and effects of polycyclic aromatic hydrocarbons in the Tunis lagoon, Tunisia: an integrated approach using multi-level biological responses in Ruditapes decussatus.

Coastal lagoons are critical ecosystems presenting a strategic economic importance, but they are subjected to potential anthropogenic impact. As part of the Tunis lagoon (Tunisia) biomonitoring study, levels, composition pattern and sources of polycyclic aromatic hydrocarbons (PAHs) in surface sediments along with their bioavailability in clam Ruditapes decussatus were investigated in polluted (S2-S4) and reference (S1) sites. In order to investigate the contamination effects at different biological levels in clams, a wide set of biomarkers, including gene expression changes, enzymatic activities disruption and histopathological alterations, was analysed. Biomarkers were integrated in a biomarker index (IBR index) to allow a global assessment of the biological response. Principal component analysis (PCA) was used for chemical and biological data integration to rank the sampling sites according to their global environmental quality. Sediment PAHs levels ranged between 144.5 and 3887.0 ng g-1 dw in the Tunis lagoon sites versus 92.6 ng g-1 dw in the reference site. The high PAH concentrations are due to anthropogenic activities around the lagoon. PAH composition profiles and diagnostic isomer ratios analysis indicated that PAHs were of both pyrolitic and petrogenic origins. Clams sampled from S2 and S3 exhibited the highest PAH contents with 2192.6 ng g-1 dw and 2371.4 ng g-1 dw, respectively. Elevated levels of tissue PAHs were associated to an increase in biotransformation and antioxidant activities, and lipid peroxidation levels along with an overexpression of different genes encoding for general stress response, mitochondrial metabolism and antioxidant defence, in addition to the emergence of severe and diverse histopathological alterations in the clams' digestive glands. IBR index was suitable for sampling sites ranking (S1 = 0 < S4 = 0.4 < S3 = 1.15 < S2 = 1.27) based on the level of PAH-induced stress in clams. PCA approach produced two components (PC1, 83.8% and PC2, 12.2%) that describe 96% of the variance in the data and thus highlighted the importance of integrating contaminants in sediments, their bioaccumulation and a battery of biomarkers of different dimensions for the assessment of global health status of coastal and lagoon areas.

Distribution, Source, and Ecological Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Sediment of Liaodong Bay, Northeast China

Sixteen polycyclic aromatic hydrocarbons (PAHs) were determined in surface sediments from Liaodong Bay, northeast China. The concentration levels of total PAHs (Σ16PAHs) in sediment were 11.0∼249.6 ng·g-1 dry weight (dw), with a mean value of 89.9 ng·g-1 dry weight (dw). From the point of the spatial distribution, high PAHs levels were found in the western areas of Liaodong Bay. In the paper, sources of PAHs were investigated by diagnostic ratios, which indicated that pyrogenic sources were the main sources of PAHs in the sediment of Liaodong Bay. Therefore, selected PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL indexes) for evaluation probable toxic effects on marine organism.

Hazard assessment of polycyclic aromatic hydrocarbons in water and sediment in the vicinity of coalmines

Rivers feeding into the Loskop Dam, South Africa, pass through coal mining and heavily industrialised areas. Previous studies investigating mass mortalities of crocodile and fish in the river system, revealed the presence of organic compounds, including polycyclic aromatic hydrocarbons (PAHs), in their tissues. Samples were collected from nine sites within the dam in winter and summer. Liquid-liquid and microwave-assisted extraction was used for preconcentrating PAHs from water and sediment samples, respectively. Extracts were analysed by gas chromatography-mass spectrometry in the selected ion monitoring mode to determine the presence and levels of the 16 United States Environmental Protection Agency (US EPA)-priority PAHs. Significant levels of PAHs were found in both water and sediment samples. Concentrations were higher in sediments than in water, as well as in samples collected in winter. Levels of PAHs in sediments were generally higher than those reported by many researchers for other water bodies in industrialised areas. Zebrafish embryos were used to assess potential risks associated with the water and sediment, and to determine the effects of PAHs on aquatic life. Embryos, exposed to intact water and sediment samples, as well as to diluted sediment extracts, were monitored for 120 h post fertilisation. Sediment proved more toxic to zebrafish embryos than water, causing delayed embryo development and malformations. These findings are alarming as they indicate that this water system is under stress. These findings can be typical of any water system situated in a coal mining and industrial region.

Bioavailability of polycyclic aromatic hydrocarbons (PAHs) to short-neck clam (Paphia undulata) from sediment matrices in mudflat ecosystem of the west coast of Peninsular Malaysia.

The bioaccumulation and bioavailability of polycyclic aromatic hydrocarbons (PAHs) were characterized in sediment and Paphia undulata (short-neck clam) from six mudflat areas in the west coasts of Peninsular Malaysia. The concentrations of total PAHs varied from 357.1 to 6257.1 and 179.9±7.6 to 1657.5±53.9ngg -1 dry weight in sediment and short-neck clam samples, respectively. PAHs can be classified as moderate to very high level of pollution in sediments and moderate to high level of pollution in short-neck clams. The diagnostic ratios of individual PAHs and principal component analysis indicate both petrogenic and pyrogenic sources with significant dominance of pyrogenic source. The first PAHs biota-sediment accumulation factors and relative biota-sediment accumulation factors data for short-neck clam were obtained in this study, indicating a preferential accumulation of lower molecular weight PAHs. Evaluation of PAH levels in sediments and short-neck clams indicates that short-neck clam could be introduced as a good biomonitor in mudflats. The results also demonstrated that under environmental conditions, the sedimentary load of hydrocarbons appears to be one of the factors controlling their bioavailability to biota.

Decline in sediment contamination by persistent toxic substances from the outfall of wastewater treatment plant: Effectiveness of legislative actions in Korea

Legacy and new persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs) were measured in sediments near a wastewater treatment plant (WWTP) outfall in a semi-enclosed bay, to investigate the current contamination and temporal changes in these contaminants associated with regulation activities in Korea. The concentrations of most of the POPs showed clear decreasing trends with an increase in the distance from the WWTP outfall, indicating that the WWTP discharges greatly contributed to the sediment contamination by POPs. Highly significant correlations were found for most of the POPs, indicating a common source for sediment contamination. Significant declines were found in the concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (DL-PCBs), polybrominated diphenyl ethers (PBDEs), and PAHs in the sediments collected between 2005 and 2013. This result suggested that legislative actions (regulation of the PCDD/Fs in flue gas, total pollution load management, and whole effluent toxicity for WWTP discharges) and change of fuels, were likely to be effective at reducing the POP and PAH levels in sediments during the past several years. The different compositional profiles of the PCDD/Fs and PAHs between 2005 and 2013 implied changes in and/or additional sources of these contaminants. Despite a decline in the PCDD/Fs over time, the present levels of PCDD/Fs in the sediment exceeded some of the sediment quality guidelines suggested by the National Oceanic and Atmospheric Administration.

Polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs in the coastal seawater, surface sediment and oyster from Dalian, Northeast China

A total of 46 polycyclic aromatic hydrocarbons (PAHs, 21 parent and 25 alkylated) were determined in seawater, surface sediment and oyster from coastal area of Dalian, North China. The concentration of Σ46PAHs in seawater, sediment, and oyster were 136–621ng/L, 172–4700ng/g dry weight (dw) and 60.0–129 ng/g wet weight (ww) in winter, and 65.0–1130ng/L, 71.1–1090ng/g dw and 72.8–216ng/g ww in summer, respectively. High PAH levels were found in industrial area both in winter and summer. Selected PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL, TEL–PEL indexes) for evaluation probable toxic effects on marine organism and the results indicate that surface sediment from all sampling sites have a low to medium ecotoxicological risk. Daily intake of PAHs via oyster as seafood by humans were estimated and the results indicated that oyster intake would not pose a health risk to humans even 30 days after a oil spill accident near by. Water-sediment exchange analysis showed that, both in winter and summer, the fluxes for most high molecular weight PAHs were from seawater to sediment, while for low molecular weight PAHs, an equilibrium was reached between seawater and sediment.

Aliphatic and polycyclic aromatic hydrocarbon contamination in surface sediment of the Chitrapuzha River, South West India

ABSTRACTDistribution (seasonal and spatial) of aliphatic and polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Chitrapuzha River, Cochin, India, was investigated using gas chromatography. Significantly high concentrations prevailed during the pre-monsoon season with the industrial zones of the river appearing to be hot spots with particularly elevated levels of the hydrocarbons. AHCs ranged between 7754 and 41,173 ng/g with an average of 25,256 ng/g, while total PAHs varied from 5046 to 33,087 ng/g. n-Alkane indices and PAH diagnostic ratios point to petroleum contamination in the sediments. The significance of PAHs in the sediments was explored using universally accepted interpretation tools. Observed levels of PAHs in sediments of Chitrapuzha are likely to cause adverse effects on biota.

Concentrations and Sources of Polycyclic Aromatic Hydrocarbons in Water and Sediments from the Huaihe River, China

Surface water and sediments were collected from eleven locations on the middle region of Huaihe River to evaluate the environmental effects of urban and industrial activities. The concentrations of sixteen polycyclic aromatic hydrocarbons (PAHs) in water and sediments were between 1.2–5.1 µg/L and 72–139 ng/g, respectively. High levels of PAHs in water were recorded in comparison to those of other countries, while the concentrations in sediments were low to moderate levels. A weak positive correlation was observed (R2 = 0.49, P = 0.13) between PAHs and total organic carbon in water. However, a significant positive correlation (R2 = 0.79, P = 0.004) was found in sediments, which indicated that total organic carbon was a factor in PAH levels in sediments but not in water. The parent ratios were studied by principal component analysis that showed the PAHs from water were predominantly derived from coal combustion (34%), oil spills (49%), and vehicular emissions (17%), while the major PAH sources to sediments were coal combustion. Using the ecological toxic equivalency factor index, it was concluded that the PAHs levels may provide a potential risk in water but not in sediments.

Coal-tar pavement sealant use and polycyclic aromatic hydrocarbon contamination in urban stream sediments

Polycyclic aromatic hydrocarbons (PAHs) can occur at levels of environmental concern in stream sediments from urban and industrial watersheds. Recent studies indicate that coal-tar sealant use on parking lots may have been the major source of PAHs to urban streams in the eastern US over the past 40 years. This study evaluates the spatial distribution of PAHs in urban stream and pond sediments in Galloway Creek in Springfield, Missouri by focusing specifically on parking lots with and without coal-tar sealants as contamination source areas. Multiple-linear regression analysis is used to evaluate the spatial connectivity of contaminated sediment to potential source areas and compare the relative influence of watershed source factors and reach sediment variability on sediment PAH levels. Sediments from coal-tar sealed parking lots and the streams that drain them are enriched in PAHs at concentrations considered toxic to aquatic life, with concentrations that are, on average, 35 and 480 times greater than those of unsealed asphalt and concrete lots, respectively. Moreover, sediment PAH concentrations are strongly correlated with the percentage of sealed parking lot area within the upstream drainage area of the sampling site, in contrast to total parking lot area or sediment composition. Metal and nutrient contaminants are poorly correlated with sealed lot area indicating a wider range of urban source inputs. Finally, parking lots with coal-tar coatings contribute >80% of the total PAH concentration in urban stream and pond sediments in Galloway Creek. If coal-tar sealant use ended, sediment PAH concentrations would probably decrease over time to levels not harmful to sediment-dwelling organisms.

Compound- and Mixture-Specific Differences in Resistance to Polycyclic Aromatic Hydrocarbons and PCB-126 amongFundulus heteroclitusSubpopulations throughout the Elizabeth River Estuary (Virginia, USA)

Atlantic killifish (Fundulus heteroclitus) inhabiting the Atlantic Wood Industries Superfund Site (Elizabeth River, Portsmouth, VA, USA) are resistant to the acute toxicity and cardiac teratogenesis caused by high levels of polycyclic aromatic hydrocarbons (PAHs) from creosote. The resistance is linked to down regulation of the aryl hydrocarbon receptor (AHR) pathway. We investigated the association between CYP1 activity, as a marker of potential AHR pathway suppression, and contaminant resistance in killifish subpopulations from sites throughout the estuary that varied significantly in PAH contamination level. Adult killifish and sediments were collected from seven sites across approximately 13.7 km in river length within the estuary and from a nearby reference site. Sediment PAH levels were determined using gas chromatography mass spectrometry. Embryos obtained via manual spawning were exposed to individual AHR agonists and PAH mixtures 24 h post fertilization (hpf); CYP1 activity was determined by in ovo ethoxyresorufin-o-deethylase (EROD) at 96 hpf, and cardiac deformity severity was scored at 144 hpf. The total PAH levels measured among the sites varied from approximately 200 to 125,000 ng/g dry sediment. Overall, the resistance to teratogenesis was strongest in the subpopulations from sites in or closest to the major PAH contamination sites, but even embryos from less-contaminated sites within the Elizabeth River demonstrated at least partial resistance to many challenges. Surprisingly, all of the subpopulations tested were highly resistant to PCB-126 (3,3′,4,4′,5-pentachlorobiphenyl). However, the degree of CYP1 activity response varied significantly among subpopulations and did not always correlate strongly with resistance to teratogenesis; some subpopulations resisted the cardiac teratogenesis caused by the challenges at doses that still elicited strong EROD induction. Our results suggest that there is variation in the adaptive phenotype exhibited by laboratory-spawned embryos from killifish subpopulations throughout the estuary. Furthermore, the results show that contaminants have affected killifish subpopulations throughout the estuary, even in sites with lower levels of PAHs.

Distribution characteristics of polycyclic aromatic hydrocarbons in sediments and biota from the Zha Long Wetland, China

In this paper, the concentrations of polycyclic aromatic hydrocarbons (PAHs) were measured in biota (reed, grass, mussel, fish, and red-crowned crane) and sediments collected from seven locations in the Zha Long Wetland. PAHs were recovered from the sediments and biota by ultrasonic extraction and then analyzed by means of gas chromatography-mass spectrometry. The total PAH concentrations were 244-713 ng/g dw in sediments, 82.8-415 ng/g dw in plants and 207-4,780 ng/g dw in animals. The total sediment PAH concentrations were categorized as lower to moderate contamination compared with other regions of China and the world. In the plant samples, the accumulation abilities of reed roots and stems for PAHs were higher than those of grass roots. In addition, the concentration of individual PAHs in mussel muscles was the highest in all of the animal samples, followed by fish, feeding crane fetuses, and wild crane fetuses. Compositional analysis suggests that the PAHs in the sediments from the Zha Long Wetland were derived from incomplete biomass combustion. Risk assessment shows that the levels of PAHs in sediments are mostly lower than the effects range mean value (effects range mean), whereas only naphthalene in all sample sites was higher than the effects range low value. It is worthwhile to note that benzo(b)fluoranthene, benzo(k)fluoranthene, indeno(1,2,3-cd)pyrene and benzo(ghi)perylene were detected in crane fetal, which have potential carcinogenicity for organisms from the Zha Long Wetland.

Distribution of polycyclic aromatic hydrocarbons (PAHs) and sterols in termite nest, soil, and sediment from Great Kwa River, SE Nigeria

Costal sediment samples from Great Kwa River as well as adjoining termite nest and soil samples were analyzed for quantitative determination of polycyclic aromatic hydrocarbons (PAHs) and sterols using gas chromatography-mass spectrometry (GC-MS) in order to access the possibility of transport of biologically produced PAHs/sterols from termite nest to the sediments. The total PAH concentrations (sum of parent and alkyl) for the sediments ranged between 131.96 and 139.35 ng/g dry weight (dw) while those for the nest and soil samples were in the range 9.51-9.71 and 71.85-77.26 ng/g dw, respectively. These levels of PAHs in sediments were relatively low compared to other urban/industrial Asian and American countries. No evidence of the usual biologically produced PAHs was found, thus reducing the likelihood of transport of these compounds from the nest to the sediments. The absence of parent and alkyl PAHs in central compartment of the nest may reflect the selective fern leaves feeding pattern of the dominant termite species prevalent in the vicinity of the study site. Utilization of six selected PAH ratios such as Fla/(Fla + Pyr) (0.4-0.5), Ant/(Ant + Phe) (0.25-0.90), BaA/(BaA + Chrys) (0.45-0.61), MP/P (0.05-6.81), 1,7/(1,7 + 2,6)-DMP (0.61-0.95), and LPAH/HPAH ( 2.80-3.80) allows discrimination of PAH sources for the samples to be made with a mixed source dominance observed. Examination of sterol distributions in the samples shows relatively high abundance of cholest-5-en-3β-ol in central compartment of the nest, considered here as a consequence of metabolic conversion of phyto-/fungi sterols in the tissues of the termite species. The relatively reduced levels of stanol compounds in central compartment of the nest may be associated with their utilization by the termites for growth and development.

Distribution and characteristics of PAHs in sediments from the Mediterranean coastal environment of Egypt

To assess the contamination of polycyclic aromatic hydrocarbons (PAHs) in the Mediterranean coastal environment of Egypt, 26 sediment samples from the coastline, harbours, estuaries and coastal lakes were collected and analyzed. The sediment PAH concentrations of thirty-nine 2–6 ring PAHs ranged from 13.5 to 22,600ng/g. PAH profiles varied according to the nature of the site and its proximity to sources. Industrialized and urbanized region showed high level of PAHs contamination. In general, the contamination levels of PAHs were similar to those observed in contaminated and slightly contaminated sediments of the Mediterranean Sea. Molecular indices based on ratios of selected PAH concentrations were used to differentiate PAHs from pyrogenic and petrogenic and mixed origins. Good correlations were observed between the petrogenic index, MP/P, A-PAHs/P-PAHs and HMW/LMW. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (ERM–ERL) for evaluation of probable toxic effects on organism.

Spatial Distribution and Temporal Trends of Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments from Lake Maryut, Alexandria, Egypt

Surface and core sediments from Lake Maryut, Egypt, one of the most polluted lakes in Egypt, were analyzed for polycyclic aromatic hydro- carbons (PAHs) using gas chromatography-mass spectrometry. This investigation represents the first extensive study of the distribution and sources of PAHs in sediments from Lake Maryut. The total PAHs concentrations (sum of 39 PAH compounds) in surface sediments varied greatly depending on the sampling location and ranged from 106 to 57,800 ng/g dry weight with a mean concentration of 6,950 ng/g. The most polluted areas are distributed in areas which are mainly influenced by municipal sewage and industrial effluent discharges, suggesting a direct influence of these sources on the pollutant distribution patterns. PAH concentrations were one to two orders of magnitude higher in comparison with those reported for riverine/ estuaries systems around the world. Molecular indices, such as pyrogenic index (PI), methylphenanthrenes to phenanthrene ratio, HMWPAH/LMWPAH, A-PAHs/P- PAHs, FL/FL+PY, BaP/BaP+C, IP/IP+BgP, and Per/ ∑(penta-aromatics) were calculated to evaluate differ- ent hydrocarbon origins and their relative importance. In general, sediments from the main basin and northwest basin of Lake Maryut showed the highest PAH concentrations with petrogenic signatures, indi- cating major sources of petrogenic PAHs in the city. On the other hand, lower levels of PAHs with a pyrogenic signature were widely recorded in areas that are distant from anthropogenic sources. At other locations, both petrogenic and pyrogenic inputs were significant. The concentrations of perylene relative to the penta-aromatic isomers are dominant especially in locations associated with terrestrial inputs and in the deepest core sediments, indicating diagenetic origin for the presence of perylene. Temporal trends of PAH concentrations in both cores sediments were influenced by input pathways and followed the economic development and the environmental policies of the Egyptian Government in the last 15 years. Finally, PAH levels in sediments were compared with Sediments Quality Guidelines (effects range median-effects range low) for evaluation probable toxic effects on organism. Results suggest an ecotoxicological risk for benthic organisms mainly in the main basin area, where high concentrations of PAHs were found in sediments influenced by anthropogenic activities.

Polycyclic aromatic hydrocarbons in effluents from wastewater treatment plants and receiving streams in Tianjin, China

Surface water, suspended particulate matter, pore water, and sediment samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) in Yongding New River, South Drainage Canal and North Drainage Canal, which receive most of wastewater from industrial city of Tianjin. PAH concentrations in effluent samples of wastewater treatment plants (WTP) discharging into the South Drainage Canal and North Drainage Canal were quantified for the first time. The results showed that the discharge of the WTPs recently only contributed to the PAH contamination in the canals near the outlets of the WTPs. PAH levels in sediments of the streams were greatly higher than those in soils by riverbank probably due to receiving large amounts of untreated wastewater. Unusually high benz[a] anthracene concentration strongly influenced the seasonal and spatial variation of total PAH concentrations in South Drainage Canal. Paired samples t test of ∑Nap, Fl, Phe, Fluo and ∑Nap, Phe, Fluo, Chry concentrations, which were dominant components in the air samples from non-heating and heating season, respectively, in the suspended particulate matters from the streams showed that PAH source from air deposition was more important for Yongding New River than that for South Drainage Canal and North Drainage Canal. Source apportionment based on PAH profiles indicated that coal combustion was the major PAH contamination source, and coke oven sources and wood combustion also contributed to the PAH contamination of the streams. This was further indicated by organic petrography analysis.

Biliary fluorescent aromatic compounds (FACs) measured by fixed wavelength fluorescence (FF) in several marine fish species from the NW Mediterranean

The fixed wavelength fluoresce (FF) method was used to estimate the levels of fluorescent aromatic compounds (FACs) in the bile of fourteen fish species of commercial and/or ecological interest. Sampling was carried out in the NW Mediterranean at depths ranging from 50 to 1000m during four seasonal cruises. During the summer sampling period, some species were also collected from another site (Vilanova fishing grounds) for comparison. Baseline levels of the polycyclic aromatic hydrocarbons (PAHs) naphthalene, phenanthrene, pyrene and benzo[a]pyrene were measured. Some seasonality was observed, with reduced FF levels in summer and no differences among sites, consistent with sediment PAH levels. We discuss our results in relation to fish phylogeny, season, depth, diet, trophic level and swimming capacity. Overall FF levels indicated differences among species; the suprabenthic feeders from shallow and deep communities, and Mullus barbatus in particular, displayed elevated FF values and are potential candidates for additional monitoring studies.