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Use of passive samplers for improving oil toxicity and spill effects assessment
2014
Letinski, Daniel | Parkerton, Thomas | Redman, Aaron | Manning, Ryan | Bragin, Gail | Febbo, Eric | Palandro, David | Nedwed, Tim
Methods that quantify dissolved hydrocarbons are needed to link oil exposures to toxicity. Solid phase microextraction (SPME) fibers can serve this purpose. If fibers are equilibrated with oiled water, dissolved hydrocarbons partition to and are concentrated on the fiber. The absorbed concentration (Cpolymer) can be quantified by thermal desorption using GC/FID. Further, given that the site of toxic action is hypothesized as biota lipid and partitioning of hydrocarbons to lipid and fibers is well correlated, Cpolymer is hypothesized to be a surrogate for toxicity prediction. To test this method, toxicity data for physically and chemically dispersed oils were generated for shrimp, Americamysis bahia, and compared to test exposures characterized by Cpolymer. Results indicated that Cpolymer reliably predicted toxicity across oils and dispersions. To illustrate field application, SPME results are reported for oil spills at the Ohmsett facility. SPME fibers provide a practical tool to improve characterization of oil exposures and predict effects in future lab and field studies.
Afficher plus [+] Moins [-]Monitoring 137Cs and 134Cs at marine coasts in Indonesia between 2011 and 2013
2014
Suseno, Heny | Prihatiningsih, Wahyu Retno
Environmental samples (seawater, sediments and biota) were collected along the eastern and western Indonesian coasts between 2011 and 2013 to anticipate the possible impacts of the Fukushima radioactive releases in Indonesia. On the eastern coasts (south and north Sulawesi), the 137Cs concentrations in the seawater and sediments were 0.12–0.32Bqm−3 and 0.10–1.03Bqkg−1, respectively. On the western coasts (West Sumatra, Bangka Island, North Java, South Java and Madura island), the 137Cs concentrations in the seawater and sediments were 0.12–0.66Bqm−3 and 0.19–1.64Bqkg−1, respectively. In general, the 137Cs concentrations in the fish from several Indonesian coasts were <MDA – 109.75mBqkg−1. In contrast, the 137Cs concentrations in mollusk, crab and prawn were 10.65–38.78, 4.02 and 6.16mBqkg−1, respectively. 134Cs was not detected in the seawater, sediments or biota. Thus, it was concluded that 137Cs on the eastern and western Indonesian coasts originated from global fallout.
Afficher plus [+] Moins [-]Source apportionment of polycyclic aromatic hydrocarbons in soils of wetlands in the Liao River Delta, Northeast China
2014
Ma, Chuanliang | Ye, Siyuan | Lin, Tian | Ding, Xigui | Yuan, Hongming | Guo, Zhigang
The polycyclic aromatic hydrocarbons (PAHs) of 55 surface soil samples from the wetlands in the Liao River Delta, Northeast China were measured in order to apportion their sources. The total concentrations of 16 US EPA priority PAHs and alkyl-PAHs in this region ranged 106–3148ngg−1 (dry weight) (average: 550±565ngg−1) and 54–5564ngg−1 (average: 517±838ngg−1), respectively. Based on the positive matrix factorization analysis of alkylated and parent PAHs, six sources of PAHs were identified including petroleum (23%), biomass burning (23%), air–soil exchange (18%), coal combustion (17%), traffic emission (14%) and biogenic origin (6%). The positive correlation between low molecular weight (LMW) PAHs and TOC contents could demonstrate a potential positive influence of TOC on the accumulations of LMW PAHs in soils by the air–soil exchange. The petrogenic PAHs may pose a limited harmful effect on aquatic organisms although they were abundant in the area.
Afficher plus [+] Moins [-]Application of direct regularization techniques and bounded–variable least squares for inverse modeling of an urban emissions inventory
2014
Vanoye, Ana Y. | Mendoza, Alberto
Inverse modeling, coupled with comprehensive air quality models, is being increasingly used for improving spatially and temporally resolved emissions inventories. Of the techniques available to solve the corresponding inverse problem, regularization techniques can provide stable solutions. However, in many instances, it is not clear which regularization parameter selection method should be used in conjunction with a particular regularization technique to get the best results. In this work, three regularization techniques (Tikhonov regularization, truncated singular–value decomposition, and damped singular–value decomposition) and three regularization parameter selection methods (generalized cross validation, the L–curve method (LC), and normalized cumulative periodograms) were applied in conjunction with an air quality model with the aim of identifying the best combination of regularization technique and parameter selection method when using inverse modeling to identify possible flaws in an urban–scale emissions inventory. The bounded–variable least–squares method (BVLS), which is not usually considered a regularization method, was also investigated. The results indicate that the choice of the regularization parameter explains most of the differences between the regularization techniques used, with the LC method exhibiting the best performance for the application described here. The results also show that the BVLS scheme provides the best agreement between the observed and modeled concentrations among the mathematical techniques tested.
Afficher plus [+] Moins [-]Changes in the concentration and relative abundance of alkanes and PAHs from the Deepwater Horizon oiling of coastal marshes
2014
Turner, R.E. | Overton, E.B. | Meyer, B.M. | Miles, M.S. | Hooper-Bui, L.
We determined changes of 28 alkanes and 43 different PAHs in 418 wetland soil samples collected on ten sampling trips to three Louisiana estuaries before and after they were oiled from the 2010 Deepwater Horizon disaster. There was a significant decline in 22 of the 28 alkane analytes (0.42%day−1), no change in 6, over 2.5years. The concentration of five aromatic petroleum hydrocarbons (PAHs) increased (range 0.25–0.70%day−1), whereas the total PAH pool did not change. Of these five, naphthalene and C-1-naphthalenes are suggested to be of higher toxicity than the other three because of their relatively higher volatility or solubility. The relative proportions of alkane analytes, but not PAHs, does not yet resemble that in the pre-oiled marshes after 3years, The trajectories of nine indicators for degradation/weathering were either inconclusive or misleading (alkanes) or confirmed the relatively meager degradation of PAHs.
Afficher plus [+] Moins [-]Particle nucleation in a forested environment
2014
Nallathamby, Punith D. | Hopke, Philip K. | Rossner, Alan | Dhaniyala, Suresh | Marzocca, P. (Piergiovanni) | Petaja, Tuukka | Barthelmie, Rebecca J. | Pryor, Sara C.
Atmospheric nucleation is now recognized to be an important source of ambient particles. In this study, ground–based measurements using a tower were used to observe new particle formation in the Morgan Monroe State Forest (MMSF) in Southwestern Indiana in May 2008. Nucleation was observed at MMSF on a number of days through examination of the particle size distributions. Most of these events were nucleation and growth events that are typical of regional nucleation phenomena. The particle size and sulfuric acid concentration data were used to investigate the mechanism for the observed nucleation events. Four of the ten observed nucleation events were clearly the result of activation of pre–existing clusters. The others seem likely to be the result of classical ternary nucleation.
Afficher plus [+] Moins [-]Response of the hairy mussel Trichomya hirsuta to sediment-metal contamination in the presence of a bioturbator
2014
Lopez, L.K. | Couture, P. | Maher, W.A. | Krikowa, F. | Jolley, D.F. | Davis, A.R.
The accumulation of metals in tissue compartments of bivalve biomonitors is expected to reflect the phases in which metals are most bioavailable. In concurrent field and laboratory experiments we measured Zn, Cd and Pb concentrations in the gills and digestive glands of mussels exposed to sediments from Lake Macquarie in NSW, Australia. Mussels in the laboratory were also exposed to the bioturbating gastropod Batillaria australis. Zn, Cd and Pb concentrations in gills and digestive glands of mussels from both experiments were accumulated in proportion with levels of metal contamination in the sediments. An interaction in the field between site and tissue type was found for Cd and Pb suggesting variation in the phases in which metals are most bioavailable. No effect of bioturbation on metal accumulation in the bivalve was detected and we conclude that it is unlikely to be a significant factor in metal uptake when these species interact.
Afficher plus [+] Moins [-]PM10 black carbon and ionic species concentration of urban atmosphere in Makassar of South Sulawesi Province, Indonesia
2014
Rashid, Mohd | Yunus, Sattar | Mat, Ramli | Baharun, Sabariah | Lestari, Puji
This paper presents a study on black carbon and ionic species concentrations in PM10, sampled from the urban area of Makassar in the Province of South Sulawesi, Indonesia. The samples were collected on a weekly basis within a period of one year from February 2012 to January 2013. Results showed that the mean concentration of PM10 black carbon was 2.01±0.93μg/m3, while ionic species concentrations were found in descending order; SO42−>NO3−>Cl−>NH4+, with mean concentrations of 1.44±1.04μg/m3, 1.11±1.06μg/m3, 0.87±0.91μg/m3, 0.49±0.64μg/m3, respectively. Black carbon concentration was higher during the dry months, which may be attributed to uncontrolled biomass burning during hot and dry weather conditions. Similarly, SO42− and NH4+ concentrations were higher during the dry month seasons. On the contrary, Cl− concentration was higher during the wet months, influenced by the marine environment surrounding the area.
Afficher plus [+] Moins [-]Comparing plastic ingestion in juvenile and adult stranded short-tailed shearwaters (Puffinus tenuirostris) in eastern Australia
2014
Acampora, Heidi | Schuyler, Qamar A. | Townsend, Kathy A. | Hardesty, Britta Denise
Numerous species of seabirds have been shown to ingest anthropogenic debris, but few studies have compared ingestion rates between adults and juveniles of the same species. We investigated marine debris ingestion by short-tailed shearwaters (Puffinus tenuirostris) obtained through two stranding events on North Stradbroke Island, Australia in 2010 (n=102; adult) and 2012 (n=27; juveniles). Necropsies were conducted and solid contents found in guts were categorized into type and color. Over 67% of birds ingested anthropogenic debris: 399 pieces of debris were identified. We found no significant relationship between body condition of birds which had ingested anthropogenic debris and those that had not. Juvenile birds were more likely to ingest debris than were adult birds and juveniles ingested significantly more pieces of debris than did adults. Male and female birds ingested similar amounts and weights of debris. To determine if P. tenuirostris actively selects for certain types of debris, we compared ingested debris to samples obtained from boat-based tows. Significant differences were found, suggesting that the birds select for hard plastic, rubber and balloons.
Afficher plus [+] Moins [-]From a millennium base line to 2012: Beach litter changes in Wales
2014
Williams, A.T. | Randerson, P. | Alharbi, O.A.
Forty-five beaches at 41 bathing area locations in Wales were analysed for litter in 2000 and 2012, via a standard seven category checklist. Fourteen resorts, 2 urban, 11 village, 15 rural 3 remote, were graded, A to D. A grade beach numbers changed from 5 to19; B, 27 to 24; C, 9 to 2; D, 4 to 0, many beaches maintaining their current status. Assuming trend continuance within the next 12years, the A:B grade ratio would approach equilibrium of 44:56, with no grade C or D beaches. Recreational litter was ubiquitous; fishing materials prevalent along Cardigan Bay. New water treatment plant investment reduced sewage related debris. Despite apparent increased awareness of beach litter, improving visitor behaviour through information/education should be a future priority. Removing a few gross items could improve beach grades at little cost to local authorities and benefits to the Welsh economy.
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