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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 [-]Distribution and sources of organochlorine pesticides in sediments of the coastal East China Sea Texto completo
2012
Lin, Tian | Hu, Limin | Shi, Xuefa | Li, Yuanyuan | Guo, Zhigang | Zhang, Gan
Forty-two surface sediment samples collected from the southern coastal East China Sea (ECS) were analyzed for organochlorine pesticides (OCPs). The results showed high concentrations of DDTs and parent DDT fractions in the nearshore area, suggesting that there is still a fresh input of these species from non-point sources, probably due to the recent usage of relevant products. However, for HCHs, the high concentrations with elevated β-HCH fraction were focused at the local major river estuaries, indicating that soils-released HCH input was mainly from the major river runoffs. The distribution and composition of OCPs in the coastal ECS could be more prominently controlled by the direct regional inputs rather than the general natural sorption process on particulate organic carbon. DDTs and chlordane are more important for their potential ecotoxicological risk on neighboring benthic community in the nearshore region and the local major river estuaries.
Mostrar más [+] Menos [-]Man-induced hydrological changes, metazooplankton communities and invasive species in the Berre Lagoon (Mediterranean Sea, France) Texto completo
2012
Delpy, Floriane | Pagano, Marc | Blanchot, Jean | Carlotti, François | Thibault-Botha, Delphine
The Berre Lagoon has been under strong anthropogenic pressure since the early 1950s. The opening of the hydroelectric EDF power plant in 1966 led to large salinity drops. The zooplankton community was mainly composed of two common brackish species: Acartia tonsa and Brachionus plicatilis. Since 2006, European litigation has strongly constrained the input of freshwater, maintaining the salinity above 15. A study was performed between 2008 and 2010 to evaluate how these modifications have impacted the zooplankton community. Our results show that the community is more diverse and contains several coastal marine species (i.e., Centropages typicus, Paracalanus parvus and Acartia clausi). A. tonsa is still present but is less abundant, whereas B. plicatilis has completely disappeared. Strong predatory marine species, such as chaetognaths, the large conspicuous autochtonous jellyfish Aurelia aurita and the invasive ctenophore Mnemiopsis leidyi, are now very common as either seasonal or permanent features of the lagoon.
Mostrar más [+] Menos [-]Environmentally safe areas and routes in the Baltic proper using Eulerian tracers Texto completo
2012
Höglund, A. | Meier, H.E.M.
In recent years, the shipping of environmentally hazardous cargo has increased considerably in the Baltic proper. In this study, a large number of hypothetical oil spills with an idealized, passive tracer are simulated. From the tracer distributions, statistical measures are calculated to optimize the quantity of tracer from a spill that would stay at sea as long as possible. Increased time may permit action to be taken against the spill before the oil reaches environmentally vulnerable coastal zones. The statistical measures are used to calculate maritime routes with maximum probability that an oil spill will stay at sea as long as possible. Under these assumptions, ships should follow routes that are located south of Bornholm instead of the northern routes in use currently. Our results suggest that the location of the optimal maritime routes depends on the season, although interannual variability is too large to identify statistically significant changes.
Mostrar más [+] Menos [-]Polycyclic aromatic and aliphatic hydrocarbons pollution at the coast of Aliağa (Turkey) ship recycling zone Texto completo
2012
Neşer, Gökdeniz | Kontas, Aynur | Ünsalan, Deniz | Altay, Oya | Darılmaz, Enis | Uluturhan, Esin | Küçüksezgin, Filiz | Tekoğul, Nermin | Yercan, Funda
Aliağa Bay is one of the most important maritime zones of Turkey where shipping activity, shipbreaking industry, steel works and petrochemical complexes exist together. Polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons in sediment of the Aliağa Bay were investigated to evaluate an environmental risk assessment from PAHs contamination in 2009–2010. Aliphatic and PAHs diagnostic ratios were showed to be mainly petroleum-originated and pyrolitic contaminations, respectively. The TEL/PEL analysis suggests that Aliağa sediments were likely to be contaminated by acutely toxic PAH compounds.
Mostrar más [+] Menos [-]Testing benthic foraminiferal distributions as a contemporary quantitative approach to biomonitoring estuarine heavy metal pollution Texto completo
2012
Foster, William J. | Armynot du Châtelet, Eric | Rogerson, M. (Mike)
Biomonitoring of estuarine pollution is the subject of active research, and benthic foraminifera are an attractive group to use for these purposes due to their ubiquitous presence in saline water and wide diversity. Here, we describe a case study of biomonitoring using benthic foraminifera in the French Mediterranean lagoon, Bages-Sigean lagoon. In this case, the major pollutants of interest are heavy metals in the sediment, particularly contaminated by Cu and Cd derived from industrial and agricultural sources. The foraminiferal assemblages of the Bages-Sigean lagoon are typical of normal paralic environments, but unusually almost completely lack agglutinated forms. The density of benthic foraminifera was shown to be more influenced by the sediment characteristics rather than heavy metal pollution. However, the relative abundance of Quinqueloculina bicostata was shown to increase in the most polluted areas and we propose that this taxon may be used as an indicator of heavy metal pollution.
Mostrar más [+] Menos [-]Heavy metal pollution in sediments of a typical mariculture zone in South China Texto completo
2012
Zhang, Wenfeng | Liu, Xueping | Cheng, Hefa | Zeng, E. Y. (Eddy Y.) | Hu, Yuanan
The heavy metal inventory and the ecological risk of the estuarine sediments in Hailing Bay, an important maricultural zone along the southern coast of China, were investigated. Results show that the surface sediments were mainly polluted by As (2.17–20.34mg/kg), Ni (1.37–42.50mg/kg), Cu (1.21–58.84mg/kg) and Zn (11.69–219.22mg/kg). Furthermore, the aquafarming zone was significantly more polluted than the non-aquafarming zone, and cluster analysis suggested additional sources of heavy metal input in the aquafarming zone. As, Cr, Cu, Ni, Pb and Zn were mainly present in the non-bioavailable residual form in the surface sediments, whereas Cd was predominantly in the highly mobile acid soluble and reducible fractions. The ecological risk of the polluted sediments stemmed mainly from Cd, and from As, Cu and Pb to less degrees. The highest potential risks occurred near the aquaculture base, indicating the need to control heavy metal inputs from aquafarming activities.
Mostrar más [+] Menos [-]Determination of deployment specific chemical uptake rates for SPMD and PDMS using a passive flow monitor Texto completo
2012
O’Brien, Dominique | Komarova, Tatiana | Mueller, Jochen F.
Passive sampling techniques facilitate the time-integrated measurement of pollutant concentrations through the use of a selective receiving phase. Accurate quantification using passive sampling devices rely on the implementation of methods that will negate the effects of environmental factors (flow, temperature, etc.) or that will allow the calculation of the chemical specific rates of uptake (Rₛ) into the passive sampler employed. We have applied an in situ calibration technique based on the dissolution of gypsum to measure the average water velocity to which a sampler has been exposed. We demonstrate that the loss of gypsum from the passive flow monitor (PFM) can be applied to predict changes in Rₛ dependent on flow when using the absorbent SPMD (semipermeable membrane device) and PDMS (polydimethyl siloxan) passive samplers. The application of the PFM will enhance the accuracy of measurements made when calculating and reporting environmental pollutant concentrations using a passive sampling device.
Mostrar más [+] Menos [-]Phenolic endocrine disrupting chemicals (EDCs) in Anzali Wetland, Iran: Elevated concentrations of 4-nonylphenol, octhylphenol and bisphenol A Texto completo
2012
Mortazavi, Samar | Riyahi Bakhtiari, Alireza | Sari, Abbas Esmaili | Bahramifar, Nader | Rahbarizade, Fatemeh
We have studied the distribution and value of phenolic endocrine disrupting chemicals (EDCs) in surface sediment samples taken from Anzali Wetland, Iran. These samples were collected from 22 stations during the time span of June–May 2010. In each of the sampling stations, we detected 4-nonylphenol (4-NP), octylphenol (OP), and bisphenol A (BPA) with maximal concentrations of 29, 4.3, and 7μgg⁻¹ dry weight (dw), respectively. High levels of alkylphenols (APs) and BPA were also found near urban areas. Furthermore there were no significant differences between those stations in terms of the detected levels. One of the important factors in controlling the fate of these compounds in the aquatic environment appeared to be Total Organic Carbon (TOC). Hierarchical cluster analysis showed differences in the biomarker characteristics of EDCs and TOC between the stations. Our findings indicate that EDCs are ubiquitous in sediments from northeast Wetlands of Iran, contaminating the aquatic habitats in this area.
Mostrar más [+] Menos [-]Radionuclides in resident and migratory fishes of a wedge bank region: Estimation of dose to human beings, South India Texto completo
2012
Khan, M Feroz | Wesley, S Godwin
Baseline activity concentration of ¹³⁷Cs, ²¹⁰Po and ²¹⁰Pb was determined for 25 resident and 22 migratory fish species collected in a so-called wedge bank region in the extreme south of India. A nuclear power station is now under construction at Kudankulam near the target region and the data provide background information on the radionuclide activity concentration in the region. Three-way ANOVA revealed no significant variation in the concentrations of ¹³⁷Cs, ²¹⁰Po and ²¹⁰Pb between species based on feeding habit, habitat and migratory pattern except the effect of feeding habit on ²¹⁰Po concentration (p<0.05). The annual dose due to radionuclide ingestion through the fishes was calculated based on the survey results of fish consumption rates for the local population. The dose due to ¹³⁷Cs was negligibly small while those due to ²¹⁰Po and ²¹⁰Pb varied from 1.2 to 36.9 and 0.2 to 2.9μSvyr⁻¹, respectively.
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