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Trace metal concentrations in Spartina densiflora and associated soil from a Patagonian salt marsh Full text
2014
Idaszkin, Yanina L. | Bouza, Pablo J. | Marinho, Carmen H. | Gil, Mónica N.
The objectives of this study were to (i) assess in situ trace metal concentrations in soil and in Spartina densiflora in a Patagonian salt marsh (Rawson, Chubut, Argentina) and (ii) investigate the relationship between trace metal concentrations in soils and in plants to improve our knowledge regarding the ability of S. densiflora to take up and accumulate trace metals from the soil within its native region. Our results indicate that the soil and S. densiflora exhibit low metal concentrations in the Rawson salt marsh. S. densiflora accumulates Zn in below- and above-ground plant structures and Cr in below-ground parts. These results suggest at the time of this study there is scarce human impact associated with metals in the Rawson salt marsh.
Show more [+] Less [-]The environmental release and fate of antibiotics Full text
2014
Manzetti, Sergio | Ghisi, Rossella
Antibiotics have been used as medical remedies for over 50years and have recently emerged as new pollutants in the environment. This review encompasses the fate of several antibiotics in the environment, including sulfonamides, nitrofurans, terfenadines, cephalosporins and cyclosporins. It investigates the cycle of transfer from humans and animals including their metabolic transformation. The results show that antibiotic metabolites are of considerable persistence and are localized to ground-water and drinking water supplies. Furthermore, the results also show that several phases of the cycle of antibiotics in the environment are not well understood, such as how low concentrations of antibiotic metabolites in the diet affect humans and animals. This review also shows that improved wastewater decontamination processes are remediating factors for these emerging pollutants. The results obtained here may help legislators and authorities in understanding the fate and transformation of antibiotics in the environment.
Show more [+] Less [-]Nitrogen and phosphorus losses from agricultural systems in China: A meta-analysis Full text
2014
Cao, Di | Cao, Wenzhi | Fang, Jing | Cai, Longyan
Studies worldwide have indicated that agricultural pollution is the main source of nitrogen and phosphorus (N and P) in surface waters. A systematic understanding of N and P sources and sinks in agricultural systems is important for selecting the appropriate remedial strategies to control nutrient losses and water pollution. Based on nationwide data and a long-term monitoring program in Southeast China, the nationwide spatial and temporal patterns of N and P losses and the relationships between such losses and N and P inputs and rainfall were analyzed. The results showed that the annual nutrient losses from agricultural systems in China strongly varied, and the N/P values ranged from 0.01 to 51.0, with a majority at approximately 0–20, and an arithmetic mean of 9.73; these values mostly overlap the suitable range of N/P (6–15) for red bloom algae.
Show more [+] Less [-]Copper bioavailability and toxicity to Mytilus galloprovincialis in Shelter Island Yacht Basin, San Diego, CA Full text
2014
Bosse, Casey | Rosen, Gunther | Colvin, Marienne | Earley, Patrick | Santore, Robert | Rivera-Duarte, Ignacio
The bioavailability and toxicity of copper (Cu) in Shelter Island Yacht Basin (SIYB), San Diego, CA, USA, was assessed with simultaneous toxicological, chemical, and modeling approaches. Toxicological measurements included laboratory toxicity testing with Mytilus galloprovincialis (Mediterranean mussel) embryos added to both site water (ambient) and site water spiked with multiple Cu concentrations. Chemical assessment of ambient samples included total and dissolved Cu concentrations, and Cu complexation capacity measurements. Modeling was based on chemical speciation and predictions of bioavailability and toxicity using a marine Biotic Ligand Model (BLM). Cumulatively, these methods assessed the natural buffering capacity of Cu in SIYB during singular wet and dry season sampling events. Overall, the three approaches suggested negligible bioavailability, and isolated observed or predicted toxicity, despite an observed gradient of increasing Cu concentration, both horizontally and vertically within the water body, exceeding current water quality criteria for saltwater.
Show more [+] Less [-]Kelp Gulls (Larus dominicanus) killed and injured by discarded monofilament lines at a marine recreational fishery in northern Patagonia Full text
2014
Yorio, Pablo | Marinao, Cristian | Suárez, Nicolás
Kelp Gulls (Larus dominicanus) killed and injured by discarded monofilament lines at a marine recreational fishery in northern Patagonia Full text
2014
Yorio, Pablo | Marinao, Cristian | Suárez, Nicolás
Among marine debris, monofilament fishing lines often result in negative impacts on marine organisms. We characterized marine debris and incidence of lost and discarded monofilament lines along beaches used by recreational fishers, and report the impact of lines on Kelp Gulls (Larus dominicanus) at the Bahía San Blas protected area, site of one of the main shore-based recreational fisheries of the southwestern Atlantic. Over 55% of the marine debris recorded originated from recreational fishing activities. Balls of tangled monofilament lines were found at a rate of 40.5 items per km. A total of 27 adult Kelp Gulls were found entangled with monofilament. All individuals were tangled to vegetation within colony boundaries. Four of the gulls had a monofilament line protruding from the bill, showing that they may be also killed when trying to obtain bait. Our results indicate that lost or discarded monofilament lines in the Bahía San Blas recreational fishing area result in undesired impacts on coastal wildlife.
Show more [+] Less [-]Kelp Gulls (Larus dominicanus) killed and injured by discarded monofilament lines at a marine recreational fishery in northern Patagonia Full text
2014
Yorio, Pablo Martin | Marinao, Cristian Javier | Suarez, Nicolas Marcelo
Among marine debris, monofilament fishing lines often result in negative impacts on marine organisms. We characterized marine debris and incidence of lost and discarded monofilament lines along beaches used by recreational fishers, and report the impact of lines on Kelp Gulls (Larus dominicanus) at the Bahía San Blas protected area, site of one of the main shore-based recreational fisheries of the southwestern Atlantic. Over 55% of the marine debris recorded originated from recreational fishing activities. Balls of tangled monofilament lines were found at a rate of 40.5 items per km. A total of 27 adult Kelp Gulls were found entangled with monofilament. All individuals were tangled to vegetation within colony boundaries. Four of the gulls had a monofilament line protruding from the bill, showing that they may be also killed when trying to obtain bait. Our results indicate that lost or discarded monofilament lines in the Bahía San Blas recreational fishing area result in undesired impacts on coastal wildlife. | Fil: Yorio, Pablo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina. Wildlife Conservation Society; Estados Unidos | Fil: Marinao, Cristian Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina | Fil: Suarez, Nicolas Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Nacional Patagónico; Argentina
Show more [+] Less [-]Polycyclic aromatic hydrocarbons (PAHs) in the mariculture zones of China’s northern Yellow Sea Full text
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.
Show more [+] Less [-]Status of trace metals in surface seawater of the Gulf of Aqaba, Saudi Arabia Full text
2014
Al-Taani, Ahmed A. | Batayneh, Awni | Nazzal, Yousef | Ghrefat, Habes | Elawadi, Eslam | Zaman, Haider
The Gulf of Aqaba (GoA) is of significant ecological value with unique ecosystems that host one of the most diverse coral communities in the world. However, these marine environments and biodiversity have been threatened by growing human activities. We investigated the levels and distributions of trace metals in surface seawater across the eastern coast of the Saudi GoA. Zn, Cu, Fe, B and Se in addition to total dissolved solids and seawater temperature exhibited decreasing trends northwards. While Mn, Cd, As and Pb showed higher average levels in the northern GoA. Metal input in waters is dependent on the adjacent geologic materials. The spatial variability of metals in water is also related to wave action, prevailing wind direction, and atmospheric dry deposition from adjacent arid lands. Also, water discharged from thermal desalination plants, mineral dust from fertilizer and cement factories are potential contributors of metals to seawater water, particularly, in the northern GoA.
Show more [+] Less [-]Airborne molds and mycotoxins in Serpula lacrymans–damaged homes Full text
2014
Pottier, Didier | André, Véronique | Rioult, Jean–Philippe | Bourreau, Alain | Duhamel, Chantal | Bouchart, Valerie Kientz | Richard, Estelle | Guibert, Mathieu | Verite, Philippe | Garon, David
For some years, the degradation of homes by the dry rot fungus Serpula lacrymans increased. This study described, for the first time, the fungal contamination in homes located in Low–Normandy (France) and damaged by Serpula lacrymans. Wood–decaying fungi, airborne molds, fungal species growing on building materials were investigated by cultural and molecular methods. Mycotoxins in the air were quantified by HPLC–MS/MS and the mutagenicity of fungal aerosols was also evaluated using the Ames test. The results showed that Serpula lacrymans was detected in the air for one third of homes with sometimes the co–occurrence of other ligninolytic basidiomycetes species like Donkioporia expansa. Various molds in the air and on materials (117 and 103 species, respectively) were also identified indicating the complexity of indoor mycoflora. Certain recurrent species like Aspergillus versicolor and Penicillium fellutanum were observed both on building materials and in the air. The presence of cellulolytic molds in fungal aerosols and on building materials could be used as an indicator of home degradation. Airborne culturable fungal levels were measured up to 5.8x105 Colony Forming Units (CFU) per cubic meter of the air (CFU/m3) depending on the home. Fungal concentrations also depended on the type of collector (filter or liquid) and were significantly correlated with the median of particles between 2–15μm in size. Two mycotoxins (alternariol and/or ochratoxin A) were observed in 4 homes but no mutagenic activity was found.
Show more [+] Less [-]Sulfur dioxide exposure and environmental justice: a multi–scale and source–specific perspective Full text
2014
Zou, Bin | Peng, Fen | Wan, Neng | Wilson, JGaines | Xiong, Ying
Recent studies examining racial and ethnic inequities in exposure to urban air pollution have led to advances in understanding the nature and extent of overall concentration exposures by pollutant, demarcated by disadvantaged groups. However, the stability of inequities at various spatial units and the exposure by air pollution sources are often neglected. In this case study from the Dallas–Fort Worth (Texas, USA) area, we used Geographic Information Systems (GIS) and an air dispersion model to estimate environmental justice impacts at different spatial scales (i.e., zip code, census tract, block group) and by source (i.e., industrial pollution sources, vehicle pollution sources, industry and vehicle pollution sources combined). Using whites as a reference, blacks and other races were more likely to be exposed to higher sulfur dioxide (SO2) concentrations although the Odds Ratio (OR) varied substantially by pollution source type [e.g., industrial pollution source based: (OR=1.80; 95% CI (Confidence Interval): 1.79–1.80) vs. vehicle pollution source based: (OR=2.70; 95% CI: 2.68–2.71)] and varied less between spatial scales [for vehicle pollution sources, (OR=2.70; 95% CI: 2.68–2.71) at the census tract level but was (OR=2.54; 95% CI: 2.53–2.55) at the block group scale]. Similar to the pattern of racial inequities, people with less education (i.e., less than 12 years of education) and low income (i.e., per capital income below $20 000) were more likely to be exposed to higher SO2 concentrations, and those ORs also varied greatly with the pollution sources and slightly with spatial scales. It is concluded that the type of pollution source plays an important role in SO2 pollution exposure inequity assessment, while spatial scale variations have limited influence. Future studies should incorporate source–specific exposure assessments when conducting studies on environmental justice.
Show more [+] Less [-]Use of passive samplers for improving oil toxicity and spill effects assessment Full text
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.
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