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Comparison of recreational health risks associated with surfing and swimming in dry weather and post-storm conditions at Southern California beaches using quantitative microbial risk assessment (QMRA) Texto completo
2012
Tseng, Linda Y. | Jiang, Sunny C.
Southern California is an increasingly urbanized hotspot for surfing, thus it is of great interest to assess the human illness risks associated with this popular ocean recreational water sport from exposure to fecal bacteria contaminated coastal waters. Quantitative microbial risk assessments were applied to eight popular Southern California beaches using readily available enterococcus and fecal coliform data and dose-response models to compare health risks associated with surfing during dry weather and storm conditions. The results showed that the level of gastrointestinal illness risks from surfing post-storm events was elevated, with the probability of exceeding the US EPA health risk guideline up to 28% of the time. The surfing risk was also elevated in comparison with swimming at the same beach due to ingestion of greater volume of water. The study suggests that refinement of dose-response model, improving monitoring practice and better surfer behavior surveillance will improve the risk estimation.
Mostrar más [+] Menos [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Texto completo
2012
Harmelin-Vivien, M. L. (Mireille L.) | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Véronique | Mellon-Duval, Capucine | Tronczyński, Jacek | Cossa, Daniel
Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Texto completo
2012
Harmelin-Vivien, M. L. (Mireille L.) | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Véronique | Mellon-Duval, Capucine | Tronczyński, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and ¹³⁷Cs) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism’s trophic level (δ¹⁵N). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and ¹³⁷Cs, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants.
Mostrar más [+] Menos [-]Differential biomagnification of PCB, PBDE, Hg and Radiocesium in the food web of the European hake from the NW Mediterranean Texto completo
2012
Harmelin-vivien, Mireille | Bodiguel, Xavier | Charmasson, Sabine | Loizeau, Veronique | Mellon, Capucine | Tronczynski, Jacek | Cossa, Daniel
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and Cs-137) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (delta N-15). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and Cs-137, and increase in contaminant concentration with trophic level occurred at different rates depending on contaminants. Such differences of biomagnification patterns can be related to physico-chemical properties of the different contaminants. (C) 2012 Elsevier Ltd. All rights reserved.
Mostrar más [+] Menos [-]Perylene dominates the organic contaminant profile in the Berau delta, East Kalimantan, Indonesia Texto completo
2012
Booij, Kees | Arifin, Zainal | Purbonegoro, Triyoni
The geographical distributions of polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), hexachlorobenzene, and 1,1-dichloro-2,2-bis(4-chlorophenyl)ethene (4,4′-DDE) were studied in the Berau delta (East Kalimantan, Indonesia), using sediment sampling and passive water sampling with semipermeable membrane devices. High concentrations of perylene were observed in sediments (54–580ngg⁻¹ dry weight), and water (1–680pgL⁻¹). Perylene accounted for about 60% of the total concentrations of PAHs in the sediment. The relative abundance of the other PAHs was indicative of petrogenic sources. Concentrations of PCBs, hexachlorobenzene, and 4,4′-DDE in sediments were below or close to the detection limit (∼0.02ngg⁻¹). The analysis of a sediment core revealed no appreciable changes in the concentration of target compounds over the past three decades. We show that sediment sampling and passive water sampling are complementary techniques, and propose to bring the results of both methods to the same concentration scale, using locally derived sediment–water partition coefficients.
Mostrar más [+] Menos [-]A unique aspect of ballast water management requirements – The same location concept Texto completo
2012
Gollasch, Stephan | David, Matej
Under certain circumstances vessels do not need to meet ballast water management requirements as stated in the International Convention for the Management and Control of Ballast Water and Sediments (BWM Convention). Besides exceptions to ensure e.g., (a) the safety of a ship, (b) discharge of ballast water for the purpose of avoiding or minimizing pollution incidents, (c) uptake and discharge on high seas of the same ballast water, the same location concept comes into play as ballast water discharges from a ship at the same location where it was taken up is also excepted from BWM requirements. The term same location was not defined in this instrument, hence it is exposed to different interpretations (e.g., a terminal, a port, a larger area where two or more ports may be located). As the BWM Convention is an instrument with biological meaning, the authors recommend a biologically meaningful definition of the same location in this contribution.
Mostrar más [+] Menos [-]Mapping the pollutants in surface riverine flood plume waters in the Great Barrier Reef, Australia Texto completo
2012
Devlin, M.J. | McKinna, L.W. | Álvarez-Romero, J.G. | Petus, C. | Abott, B. | Harkness, P. | Brodie, J.
The extent of flood plume water over a 10year period was mapped using quasi-true colour imagery and used to calculate long-term frequency of occurrence of the plumes. The proportional contribution of riverine loads of dissolved inorganic nitrogen, total suspended sediments and Photosystem-II herbicides from each catchment was used to scale the surface exposure maps for each pollutant. A classification procedure was also applied to satellite imagery (only Wet Tropics region) during 11 flood events (2000–2010) through processing of level-2 ocean colour products to discriminate the changing characteristics across three water types: “primary plume water”, characterised by high TSS values; “secondary plume water”, characterised by high phytoplankton production as measured by elevated chlorophyll-a (chl-a), and “tertiary plume water”, characterised by elevated coloured dissolved and detrital matter (CDOM+D). This classification is a first step to characterise flood plumes.
Mostrar más [+] Menos [-]Water quality in the inshore Great Barrier Reef lagoon: Implications for long-term monitoring and management Texto completo
2012
Schaffelke, Britta | Carleton, John | Skuza, Michele | Zagorskis, Irena | Furnas, Miles J.
Coastal and inshore areas of the Great Barrier Reef lagoon receive substantial amounts of material from adjacent developed catchments, which can affect the ecological integrity of coral reefs and other inshore ecosystems. A 5-year water quality monitoring dataset provides a ‘base range’ of water quality conditions for the inshore GBR lagoon and illustrates the considerable temporal and spatial variability in this system. Typical at many sites were high turbidity levels and elevated chlorophyll a and phosphorus concentrations, especially close to river mouths. Water quality variability was mainly driven by seasonal processes such as river floods and sporadic wind-driven resuspension as well as by regional differences such as land use. Extreme events, such as floods, caused large and sustained increases in water quality variables. Given the highly variable climate in the GBR region, long-term monitoring of marine water quality will be essential to detect future changes due to improved catchment management.
Mostrar más [+] Menos [-]Geochemical and geo-statistical assessment of selected heavy metals in the surface sediments of the Gorgan Bay, Iran Texto completo
2012
Bastami, Kazem Darvish | Bagheri, Hossein | Haghparast, Sarah | Soltani, Farzaneh | Hamzehpoor, Ali | Bastami, Mousa Darvish
We investigated heavy metal concentrations of zinc (Zn), copper (Cu), chromium (Cr), and lead (Pb), their spatial distribution and enrichment factor index in surface sediments of the Gorgan Bay. Sediment Quality Guidelines were also applied to assess adverse biological effects of these metals. Heavy metals were determined by inductively coupled plasma-mass spectroscopy (ICP-MS). The results indicated mean concentrations (ppm) of heavy metals were (mean±S.D.) Pb: 11.5±4.88, Cu: 18±8.83, Zn: 42±22.15 and Cr: 32±15.19. Based on Enrichment index, the Gorgan Bay is a low-enriched to non-enriched bay. Heavy metal contents were lower than the standard limits of PEL, ERL, and ERM that reveal no threatening influence of the metals in the Bay.
Mostrar más [+] Menos [-]Pilot study on effects of nanoparticle exposure on Crassostrea virginica hemocyte phagocytosis Texto completo
2012
Abbott Chalew, Talia E. | Galloway, Justin F. | Graczyk, Thaddeus K.
Little is known about engineered nanoparticles (NPs) exposures on oysters. As sessile filter feeders, oysters are likely to be exposed to NPs suspended in the water column with unknown effects of NP exposure on oyster functioning. Our study indicates that waterborne NPs alter oyster hemocyte phagocytosis dynamics, an indication of sub-lethal effects of NP exposures. Silver NPs, titanium dioxide (TiO₂) NPs, and silver nitrate exposures reduced phagocytosis compared to the control. Increasing TiO₂ NPs and silver nitrate concentrations reduced phagocytosis. Silver NPs, up to 120ppb, increased phagocytosis, but higher concentrations reduced phagocytosis.
Mostrar más [+] Menos [-]Genotoxicity and development effects of brominated flame retardant PBDEs and UV-exposed PBDEs on grass shrimp (Palaemonetes pugio) embryo Texto completo
2012
Lee, Hyo Jin | Kim, Gi Beum | Lee, Richard F.
To understand how polybrominated diphenyl ethers (PBDEs) affect the hatching sensitivity of grass shrimp embryos in different developmental stages, the hatching rates of embryos were measured after PBDE exposure on the early- and late-stage embryo of grass shrimp. PBDEs had no clear influence on the hatching rate. Also, to investigate on the reproductive and genetic toxicities of UV-exposed PBDEs, the hatching rate and DNA damage of stage 7 embryos were also measured. PBDEs had no significant impact on the hatching rate and DNA damage of grass shrimp in most experimental conditions regardless of embryo developmental stage or UV exposure, but in the case of UV-exposed BDE-47, the hatching rate was decreased, suggesting a potential reproductive toxicity. This research is meaningful because it is the first study to propose that PBDEs can cause reproductive toxicity in marine organism, after flowing into the ocean and undergoing photochemical reactions stimulated by UV.
Mostrar más [+] Menos [-]Molecularly imprinted polymer for selective extraction of malachite green from seawater and seafood coupled with high-performance liquid chromatographic determination Texto completo
2012
Lian, Ziru | Wang, Jiangtao
In this paper, a highly selective sample cleanup procedure combining molecular imprinting technique (MIT) and solid-phase extraction (SPE) was developed for the isolation of malachite green in seawater and seafood samples. The molecularly imprinted polymer (MIP) was prepared using malachite green as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The imprinted polymer and non-imprinted polymer were characterized by scanning electron microscope and static adsorption experiments. The MIP showed a high adsorption capacity and was used as selective sorbent for the SPE of malachite green. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chromatography with diodearray detection for the analysis of malachite green in seawater and seafood samples was also established. Finally, five samples were determined. The results showed that malachite green concentration in one seawater sample was at 1.30μgL⁻¹ and the RSD (n=3) was 4.15%.
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