Polycyclic aromatic hydrocarbons in coastal sediments of southwest Taiwan: An appraisal of diagnostic ratios in source recognition

Fifty-seven surface sediment samples were collected from the coast of southwest Taiwan and analyzed for polycyclic aromatic hydrocarbons (PAHs). Concentrations of total PAHs (28 PAH compounds) ranged from 15 to 907 ng g⁻¹ dry weight. Diagnostic ratios showed that PAHs in the sediments of the Gaoping estuary were predominantly of petroleum origin, whereas sediments from the Kaohsiung coast contained principally combustion-derived PAHs. Principal component analysis indicated that emissions from automobiles and coal burning were the main sources of combustion-derived PAHs. The relatively high ratios of perylene/penta-aromatic PAH isomers in sediments from the Tainan coast and some off-shore stations on the Kaohsiung coast suggest a significant diagenetic PAH contribution. The study shows that certain diagnostic ratios are useful and sensitive in delineating the distribution of PAHs from specific sources in southwest Taiwan. The phenanthrene/anthracene ratio is a better indicator than the methylphenanthrenes/phenanthrene ratio for tracing petrogenic PAHs, and the benzo(a)anthracene/chrysene and indeno(1,2,3-c,d)pyrene/benzo(g,h,i)perylene ratios are more specific than the benzo(a)pyrene/benzo(e)pyrene and benzo(b)fluoranthcene/benzo(k)fluoranthcene ratios in distinguishing PAHs from various pyrogenic sources.     

Contamination of polycyclic aromatic hydrocarbons (PAHs) in surface sediments and plants of mangrove swamps in Shenzhen,China

The concentrations of 16 individual and total polycyclic aromatic hydrocarbons (∑PAHs) in sediments, roots and leaves of three mangrove swamps in Shenzhen, China, namely Futian, Baguang and Waterlands, were determined. The mean concentration of ∑PAHs in Futian (4480 ng g⁻¹) was significantly higher than that in Baguang (1262 ng g⁻¹) and Waterlands (2711 ng g⁻¹). Among the 16 PAHs, the concentration of naphthalene was the highest. Based on the ratios of phenanthrene/anthracene and fluoranthene/pyrene, PAHs in Futian and Waterlands came from petrogenic and pyrolytic sources, while Baguang was mainly from pyrolytic. More PAHs were accumulated in leaves, as reflected by its higher mean concentration of ∑PAHs (3697 ng g⁻¹) and bioconcentration factor of PAHs (BCF) (>1.5) than that in roots. The BCF values in plants collected from Futian were significantly higher than that from Waterlands. These results indicated that more attention should be paid to the PAH contamination in Futian.     

Polycyclic aromatic hydrocarbons in sediments of the Great Barrier Reef region,Australia

At present the concentrations of polycyclic aromatic hydrocarbons in sediments from the Great Barrier Reef are remarkably low. The baseline levels range from <0.01 μg kg^?1 dry wt. for benzo(k)fluoranthene and benzo(a)pyrene to <0.82 μg kg^?1 for chrysene. Measurable levels of polycyclic aromatic hydrocarbons have only been found in small areas close to sites frequently visited by power boats. Sediments from Townsville and Gladstone Harbours on the coast adjacent to the reef are polluted with polycyclic aromatic hydrocarbons to a similar degree to that reported for coastal sediments in similar locations in other parts of the world.     

Distributions of polycyclic aromatic hydrocarbons in the Daliao River Estuary of Liaodong Bay, Bohai Sea (China)

The distributions of 16 polycyclic aromatic hydrocarbons (PAHs) were determined in the aqueous phase, suspended particulate matter (SPM), sediment, and pore water of the Daliao River Estuary in Liaodong Bay, Bohai Sea (China). Total PAH concentrations ranged from 139.16 to 1717.87 ng L⁻¹ in surface water, from 226.57 to 1404.85 ng L⁻¹ dry weight in SPM, from 276.26 to 1606.89 ng g⁻¹ dry weight in sediments, and from 10.20 to 47.27 μg L⁻¹ in pore water. PAH concentrations were at relatively moderate levels in water, SPM, sediment and pore water in comparison with those reported for other estuary and marine systems around the world. Sedimentary PAH concentrations decreased offshore owing to active deposition of laterally-transported river-borne particles. PCA analysis of the possible PAH source suggested petrogenic and pyrolytic PAH inputs in the studied region.     

Fate of polycyclic aromatic hydrocarbon (PAH) contamination in a mangrove swamp in Hong Kong following an oil spill

The fate of polycyclic aromatic hydrocarbon (PAH) contamination in a mangrove swamp (Yi O) in Hong Kong after an oil spill accident was investigated. The concentrations and profiles of PAHs in surface sediments collected from five quadrats (each of 10 m×10 m) covering different degrees of oil contamination and the most contaminated mangrove leaves were examined in December 2000 (30 days after the accident) and March 2001 (126 days later). The concentrations of total PAHs in surface sediments ranged from 138 to 2135 ng g⁻¹, and PAHs concentrations decreased with time. In the most contaminated sediments, total PAHs dropped from 2135 (30 days) to 1196 ng g⁻¹ (120 days), and the decrease was smaller in less contaminated sediments. The percentage reduction in sediment PAHs over three months (44%) was less significant than that in contaminated leaves (85%), indicating PAH in or on leaves disappeared more rapidly. The PAH profiles were very similar in sediments collected from quadrats Q1 and Q2 with benzo[a]anthracene and pyrene being the most abundant PAH compounds, but were different in the other three quadrats. The proportion of the light molecular weight PAHs to total PAHs increased after three months, especially phenanthrene. Results suggest that physical and photo-chemical weathering (tidal washing and photo-oxidation) of crude oil in surface sediments and on plant leaves were important processes in the first few months after the oil spill. The PAH contamination in Yi O swamp came from both petrogenic and pyrolytic sources. The petrogenic characteristic in the most contaminated sediment was confirmed with high values of phenanthrene to anthracene ratio (>10) and low values of fluoranthene to pyrene ratio (0.3–0.4).     

Atmospheric Concentrations and Phase Partitioning of Polycyclic Aromatic Hydrocarbons in Izmir,Turkey

Ambient air polycyclic aromatic hydrocarbon (PAH) samples were collected at a suburban (n = 63) and at an urban site (n = 14) in Izmir, Turkey. Average gas‐phase total PAH (∑₁₄PAH) concentrations were 23.5 ng m^?3 for suburban and 109.7 ng m^?3 for urban sites while average particle‐phase total PAH concentrations were 12.3 and 34.5 ng m^?3 for suburban and urban sites, respectively. Higher ambient PAH concentrations were measured in the gas‐phase and ∑₁₄PAH concentrations were dominated by lower molecular weight PAHs. Multiple linear regression analysis indicated that the meteorological parameters were effective on ambient PAH concentrations. Emission sources of particle‐phase PAHs were investigated using a diagnostic plot of fluorene (FLN)/(fluorine + pyrene; PY) versus indeno[1,2,3‐cd]PY/(indeno[1,2,3‐cd]PY + benzo[g,h,i]perylene) and several diagnostic ratios. These approaches have indicated that traffic emissions (petroleum combustion) were the dominant PAH sources at both sites for summer and winter seasons. Experimental gas–particle partition coefficients (K_P) were compared to the predictions of octanol–air (K_OA) and soot–air (K_SA) partition coefficient models. The correlations between experimental and modeled K_P values were significant (r² = 0.79 and 0.94 for suburban and urban sites, respectively, p < 0.01). Octanol‐based absorptive partitioning model predicted lower partition coefficients especially for relatively volatile PAHs. However, overall there was a relatively good agreement between the measured K_P and soot‐based model predictions.     

Picoplankton structure in clear and turbid eutrophic shallow lakes: A seasonal study

The relative abundance of the different picoplankton components (eukaryotic picophytoplankton (Peuk), picocyanobacteria (Pcy) and bacterioplankton), and their relationships with the lake conditions were studied in three types of shallow lakes from the Pampa Plain (Argentina) that differ in their optical properties: clear-vegetated, phytoplankton-turbid and inorganic-turbid. All the selected lakes, but one, are characterized by their different alternative steady state (clear-vegetated and phytoplankton-turbid water phases) following the model proposed by Scheffer et al. (1993).Autotrophic and heterotrophic picoplankton abundances were analyzed seasonally in relation to environmental variables. All the lakes presented high concentrations of total nitrogen (TN) (>229 μg L⁻¹), total phosphorus (TP) (>46 μg L⁻¹) and dissolved organic carbon (DOC) (>13.7 mg L⁻¹). Clear-vegetated lakes were characterized by vertical diffuse PAR (photosynthetic active radiation) attenuation coefficient (kd_PAR) lower than 11 m⁻¹, whereas inorganic-turbid lake always showed values higher than 21.1 m⁻¹. The euphotic zone depth (Z_1%) was wider in clear-vegetated lakes (40–140 cm) and thinner in the inorganic-turbid (10–20 cm). The phytoplankton-turbid lakes presented a wide range in the values of these variables (kd_PAR: 5.2–35.8 m⁻¹; Z_1%: 10–90 cm). Phytoplankton chlorophyll-a (Chl-a) strongly differed, ranging from 1.6 to 334.6 μg L⁻¹. Picophytoplankton was mainly represented by phycocianine-rich (PC-rich) Pcy in all cases, dominating over Peuk algae. The total and relative abundances of eukaryotic picophytoplankton, Pcy and bacterioplankton, as well as the size structure of the phytoplankton community differed among the water bodies. In general, clear-vegetated water bodies exhibited similar abiotic characteristics, picophytoplankton/bacterioplankton ratios, and phytoplankton size structure. Contrarily, no clear trend was identified for the group of turbid lakes. The contrasting results obtained for the importance of the picoplankton components in phytoplankton-turbid shallow lakes evidence that the availability of the energetical and nutrient resources cannot be solely considered to predict their relative importance in this type of shallow lake.     

Distribution and source recognition of polycyclic aromatic hydrocarbons in the sediments of Hsin-ta Harbour and adjacent coastal areas,Taiwan

Thirty-three sediment samples from Hsin-ta Harbour and neighboring coastal areas were analyzed by GC-MS for polycyclic aromatic hydrocarbons (PAHs). Total concentrations of 30 analyzed parental and alkylated PAHs ( summation operator PAH) varied from 98.1 to 3382 ng/g dry weight. MP/P (methylphenanthrenes/phenanthrene) values larger than 2 coincided with very low P/A (phenanthrene/anthracene) values at inner harbour stations, revealing that a significant portion of low molecular weight PAHs are probably from petrogenic pollution sources, specifically, illegal disposal of used motor oil. The 4,6-dimethyldibenzothiophene/3,6-dimethylphenanthrene (4,6-C(2)D/3,6-C(2)P) ratio is found to be more useful than the MP/P ratio in tracing petrogenic PAHs from the inner harbour area to the adjacent coastal environment. In addition, according to hierarchical cluster analysis, collected sediments cluster in three major groups, Off-shore Group, Near-shore Group and Inner Harbour Group. Three diagnostic ratios, 4,6-C(2)D/3,6-C(2)P, PER/ summation operator PAH (perylene to summation operator PAH) and BaA/CHR (benzo(a)anthracene/chrysene), representing petrogenic, biogenic and pyrogenic origins, are found to be effective in differentiating and characterizing sediments among the groups in this study. Enrichment of pyrogenic and petrogenic PAHs in sediments collected exhibits mixing or dilution, spatially, by biogenic (or natural) PAHs.     

Induction, adaptation and recovery of lysosomal integrity in green-lipped mussel Perna viridis

Biomarkers are generally applied to detect pollution in environmental monitoring. Such biological responses should accurately reflect the stress over time in a quantitative manner. As such, the initial and maximum responses induced by stress, as well as adaptation and recovery of these biomarkers, need to be fully understood or else erroneous false-negative or false-positive may be arrived. However, most of the biomarker studies only provided information on initially induced responses under different concentrations of toxicants, while biological adaptation and recovery were poorly known. In this study, the time required for induction, adaptation and recovery of lysosomal integrity in green-lipped mussel Perna viridis upon exposure to benzo[a]pyrene was investigated over a period of 62 days. Maximum induction occurred on day 6 when lysosomal integrity was significantly reduced by 51%, and no further change or adaptation was detected thereafter. When mussels were depurated in clean seawater after 18 days of exposure to benzo[a]pyrene, a gradual recovery was observed, with lysosomal integrity returning to its background level and showing a complete recovery after 20 days of depuration. Lysosomal integrity was significantly correlated with the body burden concentrations of benzo[a]pyrene and condition index of the mussels. The relatively fast induction (6 days) and recovery (20 days) without apparent adaptation suggested that lysosomal integrity in P. viridis can serve as a good biomarker in biomonitoring, as its response is not likely to generate both false-negative and false-positive results.     

Organohalogen contaminants and trace metals in North-East Atlantic porbeagle shark (Lamna nasus)

The North-East Atlantic porbeagle (Lamna nasus) population has declined dramatically over the last few decades and is currently classified as ‘Critically Endangered’. As long-lived, apex predators, they may be vulnerable to bioaccumulation of contaminants. In this study organohalogen compounds and trace elements were analysed in 12 specimens caught as incidental bycatch in commercial gillnet fisheries in the Celtic Sea in 2011. Levels of organohalogen contaminants were low or undetectable (summed CB and BDE concentrations 0.04–0.85 mg kg⁻¹ wet weight). A notably high Cd concentration (7.2 mg kg⁻¹ wet weight) was observed in one mature male, whereas the range observed in the other samples was much lower (0.04–0.26 mg kg⁻¹ wet weight). Hg and Pb concentrations were detected only in single animals, at 0.34 and 0.08 mg kg⁻¹ wet weight, respectively. These contaminant levels were low in comparison to other published studies for shark species.     

Concentrations of unsubstituted polycyclic aromatic hydrocarbons in softshell clams from Coos Bay,Oregon, USA

Concentrations of benzo[a]pyrene (BAP) were measured in subpopulations of softshell clams, Mya arenaria, from four intertidal sites in Coos Bay from June 1976 to June 1978. Subsequently, concentrations of 15 unsubstituted polynuclear aromatic hydrocarbons (PNAH) were determined in two subpopulations from September 1978 to August 1979. There were significant differences between BAP concentrations in clams from the four sites. For the two-year period, they were highest in clams inhabiting areas adjacent to the industrialized bayfront and lowest in clams inhabiting more remote areas. There were no significant seasonal variations in BAP concentrations during this period. During the 1978–1979 study, the average total PNAH concentration in clams from the bayfront area was 555.1 μg kg^?1 compared to 76.3 μg kg^?1 for clams from a more remote environment. In general, PNAH concentrations were lowest in the fall-winter and highest during the spring-summer.     

PAHs contamination and bacterial communities in mangrove surface sediments of the Jiulong River Estuary,China

Sixteen sediment samples collected from eight transects in a mangrove swamp of the Jiulong River Estuary, Fujian, China were investigated for their content of polycyclic aromatic hydrocarbons (PAHs) and the biodegradation potential of the indigenous microorganisms. The bacterial community structures in the mangrove sediments and in enrichment cultures were also investigated. The results showed that the total PAHs concentration of mangrove sediments ranged from 280 to 1074 ng g⁻¹ dry weight, that the PAHs composition pattern in the mangrove sediments was dominated by high molecular weight PAH components (4–6 rings), and that Benzo[ghi]perylene and Indeno[1,2,3-cd]pyrene were the most dominant at different stations. Abundant PAH-degrading bacteria were found in all the stations, the values of phenanthrene-degrading bacteria ranged from 5.85 × 10⁴ to 7.80 × 10⁵ CFU g⁻¹ dry weight, fluoranthene-degrading bacteria ranged from 5.25 × 10⁴ to 5.79 × 10⁵ CFU g⁻¹ dry weight, pyrene-degrading bacteria ranged from 3.10 × 10⁴ to 6.97 × 10⁵ CFU g⁻¹ dry weight and the benzo(a)pyrene-degrading bacteria ranged from 5.25 × 10⁴ to 7.26 × 10⁵ CFU g⁻¹ dry weight. DGGE analysis of PCR-amplified 16S rDNA gene fragments confirmed that there was a remarkable shift in the composition of the bacterial community due to the addition of the different model PAH compound phenanthrene (three ring PAH), fluoranthene(four ring PAH), pyrene(four ring PAH) and benzo(a)pyrene(five ring PAH) during enrichment batch culture. Eleven strains were obtained with different morphology and different degradation ability. The presence of common bands for microbial species in the cultures and in the native mangrove sediment DNA indicated that these strains could be potential in situ PAH-degraders.     

Seasonal variations in the inorganic carbon system in the Pearl River (Zhujiang) estuary

Seasonal variations in the inorganic carbon system in the Pearl River estuary are examined based on data from five surveys during the spring, summer, fall, and winter seasons. Both total dissolved inorganic carbon (DIC) and total alkalinity (TAlk) values in the freshwater end-members are high in the dry season (>2700 μmol kg⁻¹ for DIC and >2400 μmol kg⁻¹ for TAlk) and substantially lower in the wet season (DIC and TAlk were ∼1000 and 700 μmol kg⁻¹, respectively). Riverine DIC flux and drainage basin weathering rates, however, are significantly higher in the wet season (611×10⁹ mol yr⁻¹ and 13.6×10⁵ mol km⁻² yr⁻¹) than in the dry season (237×10⁹ mol yr⁻¹ and 5.3×10⁵ mol km⁻² yr⁻¹).     

Changes in trace metals in Thalassia testudinum after hurricane impacts

Major hurricanes Emily and Wilma hit the Mexican Caribbean in 2005. Changes in trace metals in the seagrass Thalassiatestudinum prior to (May 2004, 2005) and following passage of these hurricanes (May, June 2006) were determined at four locations along a ∼130 km long stretch of coast. Before the hurricanes, essential metals were likely limiting and concentrations of potentially toxic Pb were high in a contaminated lagoon (27.5 μg g⁻¹) and near submarine springs (6.10 μg g⁻¹); the likely sources were inland sewage disposal or excessive boat traffic. After the hurricanes, Pb decreased to 2.0 μg g⁻¹ in the contaminated lagoon probably through flushing. At the northern sites, essential Fe increased >2-fold (from 26.8 to 68.3 μg g⁻¹ on average), possibly from remobilization of anoxic sediments or upwelling of deep seawater during Wilma. Thus, hurricanes can be beneficial to seagrass beds in flushing toxic metals and replenishing essential elements.     

Untersuchung des biologischen Abbaus von polycyclischen aromatischen Kohlenwasserstoffen in einer Labor-Kläranlage

Study of the Biological Degradation of Polycyclic Aromatic Hydrocarbons in a Laboratory-scale Plant A one-stage laboratory-scale wastewater treatment plant composed of a bubble column reactor with sedimentor and sludge recycle is fed with an oil/water emulsion from a contaminated site. The oil phase is highly contaminated with polycyclic aromatic hydrocarbons (PAH). The samples are taken regularly at defined points of the treatment plant (influent, reactor, return sludge, effluent). The analysis of PAH is performed by HPLC. We can show that all analysed PAH including the poorly degradable carcinogenic substances such as benzo[a]pyrene are biologically transformed. Additional measurements of the toxic and mutagenic potential of the wastewater show that in the laboratory-scale plant full removal of the carcinogenic potential is not achieved. This is due to the fact that during the biological transformation of higher condensated PAH mutagenic dead-end metabolites are produced.     

Distributions of polycyclic aromatic hydrocarbons and alkylated polycyclic aromatic hydrocarbons in Osaka Bay,Japan

Contaminations in sediments by polycyclic aromatic hydrocarbons (PAHs) and alkylated PAHs were investigated at 44 sites in Osaka Bay, Japan. Concentrations of total PAHs and alkylated PAHs were in the range 6.40–7800 ng/g dry weights and 13.7–1700 ng/g dry weights, respectively. The PAH concentrations tended to be higher along the shoreline in the vicinities of big ports, industrialized areas, and densely populated regions such as the cities of Osaka and Kobe. The major sources appeared to be pyrogenic or both pyrogenic and petrogenic at most of the sites. PAH concentrations were remarkably high at a site near Kobe, where the concentrations of dibenzo(a,h)anthracene and benzo(g,h,i)perylene exceeded the effects-range-medium concentration and eight PAHs were above the corresponding effects-range-low concentrations. Those PAHs may have been derived from the great fire associated with the large earthquake in 1995.     

Occurrence and distribution of polycyclic aromatic hydrocarbons in surface sediments of San Diego Bay marinas

Polycyclic aromatic hydrocarbons (PAHs) have garnered much attention due to their bioaccumulation, carcinogenic properties, and persistence in the environment. Investigation of the spatial distribution, composition, and sources of PAHs in sediments of three recreational marinas in San Diego Bay, California revealed significant differences among marinas, with concentrations in one site exceeding 16,000 ng g^? 1. ‘Hotspots’ of PAH concentration suggest an association with stormwater outfalls draining into the basins. High-molecular weight PAHs (4–6 rings) were dominant (> 86%); the average percentage of potentially carcinogenic PAHs was high in all sites (61.4–70%) but ecotoxicological risks varied among marinas. Highly toxic benzo(a)pyrene (BaP) was the main contributor (> 90%) to the total toxic equivalent quantity (TEQ) in marinas. PAHs in San Diego Bay marina sediments appear to be derived largely from pyrogenic sources, potentially from combustion products that reach the basins by aerial deposition and stormwater drainage from nearby streets and parking lots.     

Heavy metals and polycyclic hydrocarbon compounds in benthic organisms of the Upper Gulf of Thailand

Concentrations of heavy metals and polycyclic aromatic hydrocarbons (PAHs) were measured in bivalves collected in the Upper Gulf of Thailand. PAHs detected included acenaphthene, acenaphthylene, benzo[a]pyrene, fluoranthene, methylphenanthrene, phenanthrene and triphenylene. Benzo[a]pyrene was detected in all species at concentrations varying from 1.0 to 8.2 ng·g^?1. Concentrations of cadmium, cobalt, copper, lead and nickel were significantly lower in bivalves from the Gulf than in green mussels collected from the mouth of the Chao Phraya River. No correlation was found between metal concentrations in animals and sediment, with the exception of copper. Copper concentrations in polychaetes and clams appeared to correlate with the copper:iron ratio of sediments. High rates of degradation were observed when radiolabelled chlorobenzene, phenanthrene and chrysene were added to water and sediment of the Chao Phraya River. Rates were lower in the waters and sediment of the Gulf of Thailand. The calculated half-lives of chlorobenzene in the Gulf of Thailand and the Chao Phraya River were about 130 and 68 days, respectively.     

Occurrence and distribution of hydrocarbons in the surface microlayer and subsurface water from the urban coastal marine area off Marseilles, Northwestern Mediterranean Sea

Aliphatic (AHs) and polycyclic aromatic hydrocarbons (PAHs) were analyzed in dissolved and particulate material from surface microlayer (SML) and subsurface water (SSW) sampled at nearshore observation stations, sewage effluents and harbour sites from Marseilles coastal area (Northwestern Mediterranean) in 2009 and 2010. Dissolved and particulate AH concentrations ranged 0.05–0.41 and 0.04–4.3 μg l⁻¹ in the SSW, peaking up to 38 and 1366 μg l⁻¹ in the SML, respectively. Dissolved and particulate PAHs ranged 1.9–98 and 1.9–21 ng l⁻¹ in the SSW, amounting up 217 and 1597 ng l⁻¹ in the SML, respectively. In harbours, hydrocarbons were concentrated in the SML, with enrichment factors reaching 1138 for particulate AHs. Besides episodic dominance of biogenic and pyrogenic inputs, a moderate anthropisation from petrogenic sources dominated suggesting the impact of shipping traffic and surface runoffs on this urbanised area. Rainfalls increased hydrocarbon concentrations by a factor 1.9–11.5 in the dissolved phase.     

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 1000 m 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.