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Polycyclic Aromatic Hydrocarbons in Coastal Sediment of Klang Strait, Malaysia: Distribution Pattern, Risk Assessment and Sources  [PDF]
Seyedeh Belin Tavakoly Sany, Rosli Hashim, Aishah Salleh, Majid Rezayi, Ali Mehdinia, Omid Safari
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0094907
Abstract: Concentration, source, and ecological risk of polycyclic aromatic hydrocarbons (PAHs) were investigated in 22 stations from surface sediments in the areas of anthropogenic pollution in the Klang Strait (Malaysia). The total PAH level in the Klang Strait sediment was 994.02±918.1 μg/kg dw. The highest concentration was observed in stations near the coastline and mouth of the Klang River. These locations were dominated by high molecular weight PAHs. The results showed both pyrogenic and petrogenic sources are main sources of PAHs. Further analyses indicated that PAHs primarily originated from pyrogenic sources (coal combustion and vehicular emissions), with significant contribution from petroleum inputs. Regarding ecological risk estimation, only station 13 was moderately polluted, the rest of the stations suffered rare or slight adverse biological effects with PAH exposure in surface sediment, suggesting that PAHs are not considered as contaminants of concern in the Klang Strait.
Occurrence and Distribution of Polycyclic Aromatic Hydrocarbons in Water and Sediment Collected along the Harbour Line, Mumbai, India  [PDF]
V. Dhananjayan,S. Muralidharan,Vinny R. Peter
International Journal of Oceanography , 2012, DOI: 10.1155/2012/403615
Abstract: This study investigated the occurrence of polycyclic aromatic hydrocarbons (PAHs) in water and sediment samples collected along the harbour line, Mumbai, India. The ∑PAHs quantified in water and sediment samples were ranged from 8.66 ng/L to 46.74 ng/L and from 2608 ng/g to 134134 ng/g dry wt., respectively. Significantly high concentration of ∑PAHs was found in water samples of Sewri and sediment samples of Mahul (). PAH concentrations detected in the present study were several folds higher than the existing sediment quality criteria suggested by various statutory agencies. The PAH composition patterns in water and sediments suggest the dominance of high molecular weight compounds and indicate important pyrolytic and petrogenic sources. The occurrence of PAHs in the marine environment has attracted the attention of the scientific community as these compounds are frequently detected in seawater and sediments at increasing levels and can have adverse health effects on marine organisms and humans. PAH concentrations detected at Sewri-Mahul site were sufficiently high to pose a risk to marine organisms if they are exposed continuously to this concentration. Hence, continuous monitoring of the ecosystem is highly warranted.
Occurrence and Distribution of Polycyclic Aromatic Hydrocarbons in Water and Sediment Collected along the Harbour Line, Mumbai, India  [PDF]
V. Dhananjayan,S. Muralidharan,Vinny R. Peter
International Journal of Oceanography , 2012, DOI: 10.1155/2012/403615
Abstract: This study investigated the occurrence of polycyclic aromatic hydrocarbons (PAHs) in water and sediment samples collected along the harbour line, Mumbai, India. The ∑PAHs quantified in water and sediment samples were ranged from 8.66?ng/L to 46.74?ng/L and from 2608?ng/g to 134134?ng/g dry wt., respectively. Significantly high concentration of ∑PAHs was found in water samples of Sewri and sediment samples of Mahul ( ). PAH concentrations detected in the present study were several folds higher than the existing sediment quality criteria suggested by various statutory agencies. The PAH composition patterns in water and sediments suggest the dominance of high molecular weight compounds and indicate important pyrolytic and petrogenic sources. The occurrence of PAHs in the marine environment has attracted the attention of the scientific community as these compounds are frequently detected in seawater and sediments at increasing levels and can have adverse health effects on marine organisms and humans. PAH concentrations detected at Sewri-Mahul site were sufficiently high to pose a risk to marine organisms if they are exposed continuously to this concentration. Hence, continuous monitoring of the ecosystem is highly warranted. 1. Introduction All over the world over there have been imminent problems of pollution in many of the coastal regions resulting in significant damage to marine ecosystems. Polycyclic aromatic hydrocarbons (PAHs) are a group of over 100 different chemicals that are formed during the incomplete burning of coal, oil and gas, garbage, and other organic substances [1, 2]. These contaminants generate considerable interest because some of them are highly carcinogenic in laboratory animals and have been implicated in breast, lung, and colon cancers in humans [3–5]. Accordingly, they are included in the US EPA and the EU priority pollutants list. PAHs can reach surface waters and sediment in different ways, including atmospheric deposition, urban run-off, municipal and industrial effluents, and oil spillage or leakage [6, 7]. Owing to their low aqueous solubility and strong hydrophobic nature, these contaminants tend to associate with particulate material in the aquatic environment, with the underlying sediments as their ultimate sink [8]. Recent efforts by the EPA have been aimed at establishing sediment quality criteria in an effort to further reduce human exposure to PAH, especially via ingestion of shellfish. Sediments may be a significant source of PAH to the overlying water column particularly in areas where historical PAH input to the
Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake, North China: Concentrations, sources profiles and potential risk
Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake, North China: Concentrations, sources profiles and potential risk

Guocheng Hu,Xiaojun Luo,Fengchao Li,Jiayin Dai,Jianyang Guo,Shejun Chen,Cao Hong,Bixian Mai,Muqi Xu,
Guocheng Hu
,Xiaojun Luo,Fengchao Li,Jiayin Dai,Jianyang Guo,Shejun Chen,Cao Hong,Bixian Mai,Muqi Xu

环境科学学报(英文版) , 2010,
Abstract: Organochlorine pesticides(OCPs),polychlorinated biphenyls(PCBs),and polycyclic aromatic hydrocarbons(PAHs) were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river(Fuhe River) in North China.Total concentrations of OCPs,PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng/g,2.3 to 197.8 ng/g,and 101.3 to 6360.5 ng/g,respectively.The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake.For hexachlorocyclohexane(HCHs...
Study on the Grain-Size Distribution of Polycyclic Aromatic Hydrocarbons in Yangtze River Sediment
长江武汉段不同粒径沉积物中多环芳烃(PAHs)分布特征

FENG Jing-lan,NIU Jun-feng,
冯精兰
,牛军峰

环境科学 , 2007,
Abstract: Sediments collected from Yangtze River were separated into five size fractions ( > 200 microm, 200 - 125 microm, 125 - 63 microm, 63 - 25 microm, <25 microm) by wet sieving. The concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) listed as U.S. EPA priority pollutants were determined in the fractionated sediments. Sigma PAHs concentrations ranged from 26.1 to 7135.9 ng/g and varied largely among the different size fractions. The highest Sigma PAHs concentration (7135.9 ng/g) was associated with the largest size fraction ( > 200 microm) while the fine silt fraction (63 - 25 microm) contained the lowest Sigma PAHs concentration, 26.1 ng/g. Although the PAHs concentrations difference among different fractions was great, the composition of PAHs in the five size fractions showed similar pattern dominated by PAHs with three or more rings. Sediment particles less than 25 microm contributed 75% of the Sigma PAHs, while comprising 38.6% of bulk sediment dry weight. A significant positive correlation (p < 0.01) between PAHs and total organic carbon (TOC) existing for all size fractions demonstrated that TOC was important for PAHs distribution in sediments. Additionally, sediment organic matter type and structure also played an important role in PAHs distribution in different grain size fractions.
Spatial Heterogeneity and Autocorrelation of Polycyclic Aromatic Hydrocarbons in the Sediment of Minjiang River in Fuzhou City
闽江福州段沉积物中多环芳烃的空间分布异质性研究

CHEN Wei-feng,NI Jin-zhi,YANG Hong-yu,WEI Ran,YANG Yu-sheng,
陈卫锋
,倪进治,杨红玉,魏然,杨玉盛

环境科学 , 2012,
Abstract: Polycyclic aromatic hydrocarbons (PAHs) are a typical persistent organic pollutants in environment. In order to explore the spatial distribution pattern of PAHs in the sediment of Minjiang River in Fuzhou City, the spatial heterogeneity analyses of PAHs in the sediment were studied with traditional statistics and geostatistics. The results showed that the variation degree of PAHs concentrations was moderate, the coefficient of variations (CV) ranged from 39% to 90%. The nugget/sill ratio of 3-ring PAH concentration was 0.307, which indicated a moderate spatial correlation, while the nugget/sill ratios of other PAHs were less than 0.25, which indicated strongly spatial correlations. The fractal dimension values and Moran's I values indicated that the spatial heterogeneity of lower-ring PAHs was stronger than those of high-ring PAHs. Moran's I values of three or more ring PAHs decreased with the increase of the distance. And as the distance ranged from 0 to 25.0 km, their spatial autocorrelations were weaken with the distance. A good superposition and the approximate isotropic of the semivariogram values in the northeast-southwest, southeast-northwest and east-west were observed. However, with the effect of water flow, the semivariation values of the PAHs concentrations in the south-north were different from those in the other three directions. The result of cross-validation showed that the ordinary Kriging interpolation method can well predict the spatial distribution of PAHs in the sediment of Minjiang river in Fuzhou City. The PAH concentrations approximately showed a downward trend with the water flow direction.
Polycyclic aromatic hydrocarbons with SPICA  [PDF]
O. Berne,C. Joblin,G. Mulas,A. G. G. M. Tielens,J. R. Goicoechea
Physics , 2009, DOI: 10.1051/spica/200903005
Abstract: Thanks to high sensitivity and angular resolution and broad spectral coverage, SPICA will offer a unique opportunity to better characterize the nature of polycyclic aromatic hydrocarbons (PAHs) and very small grains (VSGs), to better use them as probes of astrophysical environments. The angular resolution will enable to probe the chemical frontiers in the evolution process from VSGs to neutral PAHs, to ionized PAHs and to "Grand-PAHs" in photodissotiation regions and HII regions, as a function of G$_0$/n (UV radiation field / density). High sensitivity will favor the detection of the far-IR skeletal emission bands of PAHs, which provide specific fingerprints and could lead to the identification of individual PAHs. This overall characterization will allow to use PAH and VSG populations as tracers of physical conditions in spatially resolved protoplanetary disks and nearby galaxies (using mid-IR instruments), and in high redshift galaxies (using the far-IR instrument), thanks to the broad spectral coverage SPICA provides. Based on our previous experience with ISO and Spitzer we discuss how these goals can be reached.
Polycyclic Aromatic Hydrocarbons in Urban Stream Sediments  [PDF]
Jejal Reddy Bathi,Robert E. Pitt,Shirley E. Clark
Advances in Civil Engineering , 2012, DOI: 10.1155/2012/372395
Abstract: Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants of high environmental concern with known carcinogenic activity. Although literature documents PAH fate in urban runoff, little is known about their distribution on sediment sizes, which is essential for determining their treatability and fate in receiving waters. This paper has quantified the concentrations of selected PAHs in urban creek sediments and examined possible relationships between sediment PAH content and sediment characteristics, such as particle size, volatile organic content (VOC), and sediment chemical oxygen demand (SCOD). SCOD, VOC, and PAH concentrations of sediments showed a bimodal distribution by particle size. The large diameter sediments had the highest VOC and also had the highest PAH concentrations. The spatial variation of PAH content by sediment sizes also was statistically significant; however, the mass of the PAH material was significantly affected by the relative abundance of the different particle size classes in the sediment mixtures. 1. Introduction Polycyclic aromatic hydrocarbons (PAHs) are a class of frequently detected organic pollutants in urban stormwater runoff. According to Metre et al. [1], PAH levels in urban freshwater sediments in North America have increased over time, indicating additional discharges associated with industrialization and urbanization, including increased use of vehicles and wear and tear of asphalt [1–3]. For example, Stein et al. [4] found PAHs in storm fluxes ranged from 1.3?g/km2 for the largely undeveloped Arroyo Sequit watershed to 224?g/km2 for the highly urbanized Verdugo Wash watershed in California, USA. Similarly, according to Huston et al. [5], there is an increase in the PAHs and other contaminant flux in traffic and industrial areas compared to outer suburbs, implicating these developments positively influencing PAHs contribution in the runoff. The relative distribution of individual PAHs in stormwater runoff can indicate their originating source category, with high molecular weight PAHs indicating pyrogenic (combustion) sources, whereas low molecular weight PAHs indicating petrogenic sources. However, tracking sources in this manner becomes questionable if the expected environmental biological or physical degradation processes change the relative abundance of the different PAHs in runoff. Regardless of the type of PAH source in urban areas, stormwater is a major delivery system of PAHs to receiving water bodies. It is important to understand the behavior of PAHs at their source and sink, that is, in
Deuterated polycyclic aromatic hydrocarbons: Revisited  [PDF]
Kirstin D. Doney,Alessandra Candian,Tamami Mori,Takashi Onaka,A. G. G. M. Tielens
Physics , 2015,
Abstract: The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of HII regions in the Milky Way, Large Magellanic Cloud (LMC), and Small Magellanic Cloud (SMC) obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Fifty-three HII regions were observed in the NIR (2.5-5 {\mu}m), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. We see emission features between 4.4-4.8 {\mu}m, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case of M17b, this feature is not observed at all. Based on the weak or absent PAD features in most of the observed spectra, it is suggested that the mechanism for PAH deuteration in the ISM is uncommon.
Determination of Polycyclic Aromatic Hydrocarbons in Industrial Harbor Sediments by GC-MS  [PDF]
Cheng-Di Dong,Chih-Feng Chen,Chiu-Wen Chen
International Journal of Environmental Research and Public Health , 2012, DOI: 10.3390/ijerph9062175
Abstract: Analysis of the 16 polycyclic aromatic hydrocarbons (PAHs) of the US Environmental Protection Agency priority pollutant list was carried out in sediment samples of an industrial port in the southern Kaohsiung Harbor of Taiwan which is supposed to be extensively polluted by industrial wastewater discharges. The determination and quantification of PAHs in sediment samples were performed using gas chromatography coupled to mass spectrometry (GC-MS) with the aid of deuterated PAH internal standards and surrogate standards. The total concentrations of the 16 PAHs varied from 4,425 to 51,261 ng/g dw, with a mean concentration of 13,196 ng/g dw. The PAHs concentration is relatively high in the river mouth region, and gradually diminishes toward the harbor region. Diagnostic ratios showed that the possible source of PAHs in the industrial port area could be coal combustion. As compared with the US Sediment Quality Guidelines (SQGs), the various observed levels of PAHs exceeded the effects range median (ERM), and could thus cause acute biological damages. The results can be used for regular monitoring, and future pollution prevention and management should target the various industries in this region for reducing pollution.
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