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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.
显示更多 [+] 显示较少 [-]Dietary mercury exposure to endangered California Clapper Rails in San Francisco Bay
2014
Casazza, Michael L. | Ricca, Mark A. | Overton, Cory T. | Takekawa, John Y. | Merritt, Angela M. | Ackerman, Joshua T.
California Clapper Rails (Rallus longirostris obsoletus) are an endangered waterbird that forage in tidal-marsh habitats that pose risks from mercury exposure. We analyzed total mercury (Hg) in six macro-invertebrate and one fish species representing Clapper Rail diets from four tidal-marshes in San Francisco Bay, California. Mercury concentrations among individual taxa ranged from lowest at Colma Creek (mean range: 0.09–0.2μg/gdw) to highest at Cogswell (0.2–0.7), Laumeister (0.2–0.9) and Arrowhead Marshes (0.3–1.9). These spatial patterns for Hg matched patterns reported previously in Clapper Rail blood from the same four marshes. Over 25% of eastern mudsnails (Ilyanassa obsolete) and staghorn sculpin (Leptocottus armatus) exceeded dietary Hg concentrations (ww) often associated with avian reproductive impairment. Our results indicate that Hg concentrations vary considerably among tidal-marshes and diet taxa, and Hg concentrations of prey may provide an appropriate proxy for relative exposure risk for Clapper Rails.
显示更多 [+] 显示较少 [-]Polycyclic aromatic hydrocarbons (PAHs) in the mariculture zones of China’s northern Yellow Sea
2014
Zong, Humin | Ma, Xindong | Na, Guangshui | Huo, Chuanlin | Yuan, Xiutang | Zhang, Zhifeng
Polycyclic aromatic hydrocarbons (PAHs) were detected in water and sediment samples collected from three mariculture zones in China’s northern Yellow Sea. In these samples, total PAH concentrations ranged from 110.8ng/L to 997.2ng/L and 142.2ng/gdry weight (dw) to 750.2ng/gdw, respectively. The log KOC values of the various PAH compounds examined in this study increased with the log KOW values, which is consistent with the prediction regarding PAH behavior in the environment. However, these KOC values were lower than the predicted values as a result of the effects of organic matters, which were abundant in the mariculture water. The isomeric ratios of the PAHs in sediment indicated that the source of the PAHs in the mariculture zones were mainly pyrolytic. The TEQcarc values of PAHs ranged from 7ng TEQ/gdw to 92ng TEQ/gdw, and only a few samples met the safe criterion with respect to individual PAH concentrations.
显示更多 [+] 显示较少 [-]Spatiotemporal variability of hypoxia and eutrophication in Manila Bay, Philippines during the northeast and southwest monsoons
2014
Sotto, Lara Patricia A. | Jacinto, Gil S. | Villanoy, Cesar L.
Hypoxia in Manila Bay, Philippines was previously reported during the northeast monsoon (dry season) in February 2010. In this study, four more field surveys of the same 31 stations were conducted in July 2010, August 2011 and 2012 (wet season, southwest monsoon), and February 2011 (dry season, northeast monsoon). During the wet season, bottom hypoxia spread northward towards the coast with dissolved oxygen (DO) ranging from 0.12 to 9.22mg/L and the bay-wide average reaching 2.10mg/L. Nutrient levels were elevated, especially near the bottom where dissolved inorganic nitrogen reached 22.3μM (July 2010) and phosphorus reached 5.61μM (August 2011). High nutrient concentrations often coincided with low near-bottom DO content. Our work builds on the preliminary assessment of hypoxia in Manila Bay, the importance of repeated temporal studies, and shows hypoxia to prevail significantly during the southwest monsoon (wet season) when increased freshwater discharge caused strong water column stratification.
显示更多 [+] 显示较少 [-]Chemical characterization of coarse particulate matter in the Desert Southwest – Pinal County Arizona, USA
2014
Clements, Andrea L. | Fraser, Matthew P. | Upadhyay, Nabin | Herckes, Pierre | Sundblom, Michael | Lantz, Jeffrey | Solomon, Paul A.
The Desert Southwest Coarse Particulate Matter Study was undertaken to further our understanding of ambient concentrations and the composition of fine and coarse particles in rural, arid environments. Sampling was conducted in Pinal County, Arizona between February 2009 and February 2010. The goals of this study were to: (1) chemically characterize the coarse and fine fraction of the ambient particulate matter in terms of mass, ions, elements, bulk organic and elemental carbon; (2) examine the temporal and spatial variability of particles within the area using a series of three sampling locations and use this information to determine the contribution of local vs. regional sources; (3) collect, re–suspend, and chemically characterize various crustal sources within the area to identify differences which may isolate them (crustal sources) as independent sources, and; (4) use a receptor based modeling approach to identify particle sources and the relative impact of each on ambient PM concentrations. This work reviews the study objectives, design, site descriptions, and measurement techniques relevant to this research effort and presents the general characteristics of PM during the study period. This unique dataset will support efforts to reduce PM10 and PM2.5 concentrations in the area to below the National Ambient Air Quality Standards (NAAQS) for these pollutants.Coarse particle concentrations are, on average, approximately 5 times fine particle mass concentrations within the region. Coarse particle concentrations in Pinal County are highest during spring and fall seasons, consistent with the tilling and harvesting seasons while fine particles concentrations are highest during fall. Crustal material is the dominant component of coarse particle composition, representing 50% of the mass on average followed closely by organic matter representing 15%. Fine particles still contain a significant crustal fraction (30%) but organic matter dominates at 37% of the particle mass.
显示更多 [+] 显示较少 [-]Occurrence of contaminants of emerging concern along the California coast (2009–10) using passive sampling devices
2014
Alvarez, David A. | Maruya, Keith A. | Dodder, Nathan G. | Lao, Wenjian | Furlong, Edward T. | Smalling, Kelly L.
Three passive sampling devices (PSDs), polar organic chemical integrative samplers (POCIS), polyethylene devices (PEDs), and solid-phase microextraction (SPME) samplers were used to sample a diverse set of chemicals in the coastal waters of San Francisco Bay and the Southern California Bight. Seventy one chemicals (including fragrances, phosphate flame retardants, pharmaceuticals, PAHs, PCBs, PBDEs, and pesticides) were measured in at least 50% of the sites. The chemical profile from the San Francisco Bay sites was distinct from profiles from the sites in the Southern California Bight. This distinction was not due to a single compound or class, but by the relative abundances/concentrations of the chemicals. Comparing the PSDs to mussel (Mytilus spp.) tissues, a positive correlation exists for the 25 and 26 chemicals in common for the PEDs and SPME, respectively. Diphenhydramine was the only common chemical out of 40 analyzed in both POCIS and tissues detected at a common site.
显示更多 [+] 显示较少 [-]Refocusing Mussel Watch on contaminants of emerging concern (CECs): The California pilot study (2009–10)
2014
Maruya, Keith A. | Dodder, Nathan G. | Schaffner, Rebecca A. | Weisberg, Stephen B. | Gregorio, Dominic | Klosterhaus, Susan | Alvarez, David A. | Furlong, Edward T. | Kimbrough, Kimani L. | Lauenstein, Gunnar G. | Christensen, John D.
To expand the utility of the Mussel Watch Program, local, regional and state agencies in California partnered with NOAA to design a pilot study that targeted contaminants of emerging concern (CECs). Native mussels (Mytilus spp.) from 68 stations, stratified by land use and discharge scenario, were collected in 2009–10 and analyzed for 167 individual pharmaceuticals, industrial and commercial chemicals and current use pesticides. Passive sampling devices (PSDs) and caged Mytilus were co-deployed to expand the list of CECs, and to assess the ability of PSDs to mimic bioaccumulation by Mytilus. A performance-based quality assurance/quality control (QA/QC) approach was developed to ensure a high degree of data quality, consistency and comparability. Data management and analysis were streamlined and standardized using automated software tools. This pioneering study will help shape future monitoring efforts in California’s coastal ecosystems, while serving as a model for monitoring CECs within the region and across the nation.
显示更多 [+] 显示较少 [-]An analysis of historical Mussel Watch Programme data from the west coast of the Cape Peninsula, Cape Town
2014
Sparks, Conrad | Odendaal, James | Snyman, Reinette
The concentrations of metals in the mussel Mytilus galloprovincialis (Lamarck, 1819) prevalent along the west coast of the Cape Peninsula, Cape Town are presented. The mussels were sampled during the routine “Mussel Watch Programme” (MWP) between 1985 and 2008. Levels of Cu, Cd, Pb, Zn, Hg, Fe and Mn at Cape Point, Hout Bay, Sea Point, Milnerton and Bloubergstrand were analysed for autumn and spring and showed consistent similar mean values for the five sites. There was a highly significant temporal (annual and seasonal) difference between all metals as well as a significant difference in metal concentrations between the five sites. The concentrations of Zn, Fe, Cd and Pb were higher than previous investigations and possibly indicative of anthropogenic sources of metals. The results provide a strong motivation to increase efforts in marine pollution research in the area.
显示更多 [+] 显示较少 [-]Polychlorinated biphenyl (PCB) concentrations and congener composition in masu salmon from Japan: A study of all 209 PCB congeners by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS)
2014
Matsumoto, Reiko | Tu, Nguyen Phuc Cam | Haruta, Shinsuke | Kawano, Masahide | Takeuchi, Ichirō
We collected two subspecies of masu salmon: Oncorhynchus masou masou from four localities (southern Sea of Japan northward to Hokkaido) and O. masou ishikawae from upstream from Ise Bay close to a heavy industrial area. All 209 PCB congeners were analyzed using HRGC/HRMS. PCA ordination of congener concentrations divided data into three groups: (i) ssp. masou from Hokkaido, (ii) ssp. masou from the other regions and (iii) ssp. ishikawae. The highest ∑ PCB concentration (40.39ng/wet wt) was in ssp. ishikawae followed by ssp. masou from southern waters; however the TEQdioxin-like PCBs was highest in ssp. masou from southern water (1.96pg-TEQdioxin-like PCBs/g wet wt.) due to the high proportion of congener #126 in its complement (#126 has the highest toxic equivalency factor among congeners). There is likely a contamination source offshore in the southern Sea of Japan and/or along the migratory route of ssp. masou.
显示更多 [+] 显示较少 [-]The effect of breakwaters on the structure of marine soft-bottom assemblages: A case study from a North-Western Mediterranean basin
2014
Becchi, Claudia | Ortolani, Irene | Muir, Alexander | Cannicci, Stefano
This two-year study is the first attempt to analyse the ecological effects of breakwater systems on soft-bottom assemblages along the North Tyrrhenian coast. Differently from previous studies focusing on infauna of on-shore and off-shore sides, we compared the assemblages inhabiting the surrounding soft-bottoms not directly protected by the breakwaters, defining our sampling stations at varying distances from the breakwaters and at constant distance from the coast.Data collected revealed that abundance, species richness and M-AMBI ecological quality differed between northern and southern sides, and were related to distance from structures. Multivariate analyses of relationships between assemblages and abiotic characteristics support this hypothesis. The extension of these effects, that resulted to be weak and limited to a restricted area, could be a consequence of coastal current on local hydrodynamics. This study provides novel and critical information for the management of the coastal defence infrastructure spreading along the western coast of Italy.
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