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Linking biochemical perturbations in tissues of the African catfish to the presence of polycyclic aromatic hydrocarbons in Ovia River, Niger Delta region
2015
Obinaju, Blessing E. | Graf, Carola | Halsall, Crispin | Martin, Francis L.
Petroleum hydrocarbons including polycyclic aromatic hydrocarbons (PAHs) are a pollution issue in the Niger Delta region due to oil industry activities. PAHs were measured in the water column of the Ovia River with concentrations ranging from 0.1 to 1055.6 ng L−1. Attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectroscopy detected alterations in tissues of the African catfish (Heterobranchus bidorsalis) from the region showed varying degrees of statistically significant (P<0.0001, P<0.001, P<0.05) changes to absorption band areas and shifts in centroid positions of peaks. Alteration patterns were similar to those induced by benzo[a]pyrene in MCF-7 cells. These findings have potential health implications for resident local communities as H. bidorsalis constitutes a key nutritional source. The study provides supporting evidence for the sensitivity of infrared spectroscopy in environmental studies and supports their potential application in biomonitoring.
Afficher plus [+] Moins [-]New observations on PAH pollution in old heavy industry cities in northeastern China
2015
Song, Ningning | Ma, Junhua | Yu, Yang | Yang, Zhifeng | Li, Yingxia
This study investigated the distinctive PAHs adsorbed on street dust near various industries in the three typical industrialized cities of Daqing (DQ), Harbin (HEB) and Jilin (JL) in northeastern China. The mean ∑PAHs concentrations in street dust of DQ, HEB and JL were 1.84, 4.87, 12.38 μg/g, respectively. Typical petroleum resource city DQ had higher proportions of low and medium ringed PAHs with higher proportions of phenanthrene (Phe), naphthalene (Nap), fluoranthene (Flua) and chrysene (Chr) at industrial sites. Typical chemical processing city JL had higher proportions of medium and high ringed PAHs with higher proportions of Flua, benz[a]anthracene (BaA), pyrene (Pyr) and benzo[a]pyrene (BaP) at industrial sites. Phe, Flua, Pyr and Chr were four major PAHs from most studied industries. The distinctive PAH emissions from the ferroalloy plant were BaA and BaP. BaA and BaP concentrations decreased by 90% at sites more than 2 km away from the ferroalloy plant.
Afficher plus [+] Moins [-]Effects of oil pipeline explosion on ambient particulate matter and their associated polycyclic aromatic hydrocarbons
2015
Zhao, Yue | Cao, Lixin | Zhou, Qing | Que, Qiming | Hong, Bo
Effects of the oil pipeline explosion on PM2.5-associated polycyclic aromatic hydrocarbons (PAHs) and their substituted (alkylated, nitrated, oxygenated, hydroxyl and chlorinated) derivatives are assessed near the accident scene of Qingdao, China. Compared with those in TSP-PM2.5, gaseous phase, burn residue and unburned crude oil, eighty-nine PAHs in PM2.5 are identified and quantified to investigate the composition, temporal and spatial distribution, and sources. The concentrations of PM2.5-associated parent PAHs increase approximately seven times from the non-explosion samples to the explosion samples (mean ± standard deviation: 112 ± 2 vs 764 ± 15 ng/m3), while some substituted products (nitro- and oxy-) increase by two orders of magnitude (3117 ± 156 pg/m3 vs 740 ± 37 ng/m3). The toxicity evaluation indicates the BaP equivalent concentrations (based on the US EPA's toxicity factors) in PM2.5 are much higher than those in the other phases, especially for a long duration after the tragic accident.
Afficher plus [+] Moins [-]Detecting the effects of hydrocarbon pollution in the Amazon forest using hyperspectral satellite images
2015
Arellano, Paul | Tansey, Kevin | Balzter, Heiko | Boyd, Doreen S.
The global demand for fossil energy is triggering oil exploration and production projects in remote areas of the world. During the last few decades hydrocarbon production has caused pollution in the Amazon forest inflicting considerable environmental impact. Until now it is not clear how hydrocarbon pollution affects the health of the tropical forest flora. During a field campaign in polluted and pristine forest, more than 1100 leaf samples were collected and analysed for biophysical and biochemical parameters. The results revealed that tropical forests exposed to hydrocarbon pollution show reduced levels of chlorophyll content, higher levels of foliar water content and leaf structural changes. In order to map this impact over wider geographical areas, vegetation indices were applied to hyperspectral Hyperion satellite imagery. Three vegetation indices (SR, NDVI and NDVI705) were found to be the most appropriate indices to detect the effects of petroleum pollution in the Amazon forest.
Afficher plus [+] Moins [-]Role of entrained droplet oil on the bioavailability of petroleum substances in aqueous exposures
2015
Redman, A.D.
Bioavailability of petroleum substances is a complex issue that is affected by substance composition, the physicochemical properties of the individual constituents, and the exposure preparation system. The present study applies mechanistic fate and effects models to characterize the role of droplet oil on dissolved exposure and predicted effects from both neat and weathered crude oils, and refined fuel oils. The main effect from droplet oil is input of additional dissolved hydrocarbons to the exposure system following preparation of the initial stock solution. Toxicity was characterized using toxic units (TU) and shows that replenishment of bioavailable hydrocarbons by droplets in toxicity tests with low droplet content (e.g., <1mg/L) is negligible, consistent with typical exposure conditions following open ocean oil spills. Further, the use of volumetric exposure metrics (e.g., mg/L) introduces considerable variability and the bioavailability-based metrics (e.g., TUs) provide a more consistent basis for understanding oil toxicity data.
Afficher plus [+] Moins [-]Hydrophobic poly(alkoxysilane) organogels as sorbent material for oil spill cleanup
2015
Ozan Aydin, Gulsah | Bulbul Sonmez, Hayal
In this study, reusable poly(alkoxysilane) organogels with high absorption capacities were synthesized by the condensation of a cyclo aliphatic glycol (UNOXOL™) and altering the chain length of the alkyltriethoxysilanes. The structural and thermal properties of cross-linked poly(alkoxysilane) polymers were determined by FTIR, solid-state 13C and 29Si CPMAS NMR and TGA. The oil absorbency of poly(alkoxysilane)s was determined through oil absorption tests, absorption and desorption kinetics. Results showed that the highest oil absorbency capacities were found to be 295% for hexane, 389% for euro diesel, 428% for crude oil, 652% for gasoline, 792% for benzene, 792% for toluene, 868% for tetrahydrofuran, and 1060% for dichloromethane for the poly(alkoxysilane) gels based on UNOXOL™ and dodecyltriethoxysilane. Owing to their hydrophobic structure, the poly(alkoxysilane) organogels can selectively absorb crude oil from water. The reusability of the absorbents was quantitatively investigated, demonstrating that absorbents can be used effectively at least nine times.
Afficher plus [+] Moins [-]Biotransformation of petroleum hydrocarbons and microbial communities in seawater with oil dispersions and copepod feces
2015
Størdal, Ingvild Fladvad | Olsen, Anders Johny | Jenssen, Bjørn Munro | Netzer, Roman | Altin, Dag | Brakstad, Odd Gunnar
To determine biotransformation of components in crude oil dispersions in the presence of feces from marine copepods, dispersed oil was incubated alone, with the addition of clean or oil-containing feces. We hypothesized that the feces would contribute with nutrients to bacteria, and higher concentrations of oil-degrading bacteria, respectively. Presence of clean feces resulted in higher degradation of aromatic oil compounds, but lower degradation of n-alkanes. Presence of oil-containing feces resulted in higher degradation of n-alkanes. The effect of clean feces on aromatic compounds are suggested to be due to higher concentrations of nutrients in the seawater where aromatic degradation takes place, while the lower degradation of n-alkanes are suggested to be due to a preference by bacteria for feces over these compounds. Large aggregates were observed in oil dispersions with clean feces, which may cause sedimentation of un-weathered lipophilic oil compounds towards the seafloor if formed during oil spills.
Afficher plus [+] Moins [-]Degradation of oil by fungi isolated from Gulf of Mexico beaches
2015
Simister, R.L. | Poutasse, C.M. | Thurston, A.M. | Reeve, J.L. | Baker, M.C. | White, H.K.
Fungi of the Ascomycota phylum were isolated from oil-soaked sand patties collected from beaches following the Deepwater Horizon oil spill. To examine their ability to degrade oil, fungal isolates were grown on oiled quartz at 20°C, 30°C and 40°C. Consistent trends in oil degradation were not related to fungal species or temperature and all isolates degraded variable quantities of oil (32–65%). Fungal isolates preferentially degraded short (<C18; 90–99%) as opposed to long (C19–C36; 7–87%) chain n-alkanes and straight chain C17- and C18-n-alkanes (91–99%) compared to their branched counterparts, pristane and phytane (70–98%). Polycyclic aromatic hydrocarbon (PAH) compounds were also degraded by the fungal isolates (42–84% total degraded), with a preference for low molecular weight over high molecular weight PAHs. Overall, these findings contribute to our understanding of the capacity of fungi to degrade oil in the coastal marine environment.
Afficher plus [+] Moins [-]Impacts of Deepwater Horizon oil and associated dispersant on early development of the Eastern oyster Crassostrea virginica
2015
Vignier, J. | Donaghy, L. | Soudant, P. | Chu, F.L.E. | Morris, J.M. | Carney, M.W. | Lay, C. | Krasnec, M. | Robert, R. | Volety, A.K.
The explosion of the Deepwater Horizon (DWH) oil platform resulted in large amounts of crude oil and dispersant Corexit 9500A® released into the Gulf of Mexico and coincided with the spawning season of the oyster, Crassostrea virginica. The effects of exposing gametes and embryos of C. virginica to dispersant alone (Corexit), mechanically (HEWAF) and chemically dispersed (CEWAF) DWH oil were evaluated. Fertilization success and the morphological development, growth, and survival of larvae were assessed. Gamete exposure reduced fertilization (HEWAF: EC201h=1650μg tPAH50L−1; CEWAF: EC201h=19.4μg tPAH50L−1; Corexit: EC201h=6.9mgL−1). CEWAF and Corexit showed a similar toxicity on early life stages at equivalent nominal concentrations. Oysters exposed from gametes to CEWAF and Corexit experienced more deleterious effects than oysters exposed from embryos. Results suggest the presence of oil and dispersant during oyster spawning season may interfere with larval development and subsequent recruitment.
Afficher plus [+] Moins [-]An assessment of human influences on sources of polycyclic aromatic hydrocarbons in the estuarine and coastal sediments of China
2015
Duan, Xiaoyong | Liu, Jinqing | Zhang, Daolai | Yin, Ping | Li, Yanxia | Li, Xianguo
Sediments collected from the coastal area of China, embracing west coast of Bohai Sea, south coast of Shandong Peninsula, and the Changjiang estuary (listed in order of decreasing north latitude), were analyzed for polycyclic aromatic hydrocarbons (PAHs). ∑PAH (Sixteen US EPA priority PAHs) were 2.7–350.9ng/g. Petroleum residue was the major contributor of PAHs in the coastal sediments of China due to oil leakage from ships and offshore oil fields. The contribution of vehicular emissions in coast of North China was significantly lower than that in the Changjiang Estuary, and the reverse was true for coal combustion. PAH concentrations in the sediment core of the Changjiang estuary steadily increased upward and the variation was primarily due to economic development and severe floods. The impact on PAHs by vehicular emissions (37.2%) and petrogenic sources (45.8%) overwhelmed combustion sources (17.0%).
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