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An economic passive sampling method to detect particulate pollutants using magnetic measurements
2015
Cao, Liwan | Appel, Erwin | Hu, Shouyun | Ma, Mingming
Identifying particulate matter (PM) emitted from industrial processes into the atmosphere is an important issue in environmental research. This paper presents a passive sampling method using simple artificial samplers that maintains the advantage of bio-monitoring, but overcomes some of its disadvantages. The samplers were tested in a heavily polluted area (Linfen, China) and compared to results from leaf samples. Spatial variations of magnetic susceptibility from artificial passive samplers and leaf samples show very similar patterns. Scanning electron microscopy suggests that the collected PM are mostly in the range of 2–25 μm; frequent occurrence of spherical shape indicates industrial combustion dominates PM emission. Magnetic properties around power plants show different features than other plants. This sampling method provides a suitable and economic tool for semi-quantifying temporal and spatial distribution of air quality; they can be installed in a regular grid and calibrate the weight of PM.
Afficher plus [+] Moins [-]Will technological modernization for power generation at an oil refinery diminish the risks from air pollution to the Atlantic Rainforest in Cubatão, SE Brazil?
2015
Nakazato, Ricardo K. | Rinaldi, Mirian C.S. | Domingos, Marisa
We assessed the level of atmospheric contamination by S, N and metals before, during and after the installation of a new thermoelectric plant that provides power to an oil refinery in Cubatão, SE Brazil. We measured the foliar accumulation in Lolium multiflorum “Lema” with the aim of evaluating risks to the Atlantic Rainforest that grows in the region. Al, Co, Cr, Cu, K, N, Ni, S, V and Zn were appropriate markers of the new air contamination profile associated with the modern technology. With the exception of V, the leaf contents of these elements significantly increased between the pre-operation to post-operation phases (Al, Co, N, K, S), or only during the transition phase (Zn, Cu, Cr, Ni), and returned to the previous levels after the total shutdown of the old system. Therefore, the expected environmental gain was not achieved with the installation of the new technology.
Afficher plus [+] Moins [-]Radioactivity in the Kuwait marine environment — Baseline measurements and review
2015
Uddin, S. | Aba, A. | Fowler, S.W. | Behbehani, M. | Ismaeel, A. | Al-Shammari, H. | Alboloushi, A. | Mietelski, J.W. | Al-Ghadban, A. | Al-Ghunaim, A. | Khabbaz, A. | Alboloushi, O.
The Arabian Gulf region is moving towards a nuclear energy option with the first nuclear power plant now operational in Bushehr, Iran, and others soon to be constructed in Abu Dhabi and Saudi Arabia. Radiological safety is becoming a prime concern in the region. This study compiles available data and presents recent radionuclide data for the northern Gulf waters, considered as pre-nuclear which will be a valuable dataset for future monitoring work in this region. Radionuclide monitoring in the marine environment is a matter of prime concern for Kuwait, and an assessment of the potential impact of radionuclides requires the establishment and regular updating of baseline levels of artificial and natural radionuclides in various environmental compartments. Here we present baseline measurements for 210Po, 210Pb, 137Cs, 90Sr, and 3H in Kuwait waters. The seawater concentration of 3H, 210Po, 210Pb, 137Cs, and 90Sr vary between 130–146, 0.48–0.68, 0.75–0.89, 1.25–1.38 and 0.57–0.78mBqL−1, respectively. The 40K concentration in seawater varies between 8.9–9.3BqL−1. The concentration of 40K, total 210Pb, 137Cs, 90Sr, 226Ra, 228Ra, 238U, 235U, 234U, 239+240Pu and 238Pu were determined in sediments and range, respectively, between 353–445, 23.6–44.3, 1.0–3.1, 4.8–5.29, 17.3–20.5, 15–16.4, 28.7–31.4, 1.26–1.30, 29.7–30.0, 0.045–0.21 and 0.028–0.03Bqkg−1 dry weight. Since, radionuclides are concentrated in marine biota, a large number of marine biota samples covering several trophic levels, from microalgae to sharks, were analyzed. The whole fish concentration of 40K, 226Ra, 224Ra, 228Ra, 137Cs, 210Po and 90Sr range between 230–447, 0.7–7.3, <0.5–6.6, <0.5–15.80, <0.17, 0.88–4.26 and 1.86–5.34Bqkg−1 dry weight, respectively. 210Po was found to be highly concentrated in several marine organisms with the highest 210Po concentration found in Marica marmorata (193.5–215.6Bqkg−1 dry weight). 210Po in most dissected fish samples shows increasing concentrations in the following order: edible tissue, gills, digestive system, liver and fecal matter. Fish fecal pellets had 210Po concentrations several orders of magnitude higher than the seawater, fish muscle, and the fishes' ingested food. The high 210Po concentration in fish fecal matter, suggest that the bulk of 210Po content in fish was eventually excreted back into the environment as fecal pellets. In most fish high concentrations were noted in liver, with the highest 210Po concentration recorded in shark liver (126.2–141.5Bqkg−1 wet). Moreover, 210Po concentration in the soft tissue of molluscs (10.36–215.60Bqkg−1 dry weight) was far higher than that in fish muscle (0.05–7.49Bqkg−1 wet weight). A seasonal drop in 210Po concentration in seawater was observed to vary with the abundance of phytoplankton and macroalgae due possibly to biological dilution. 137Cs concentration in all the fish sampled was below the detection limit, and the concentration in seawater was also low; hence such low levels provide an opportunity to use this radionuclide as an indicator for any future radiocesium releases in this region.
Afficher plus [+] Moins [-]Three decades of sea water abstraction by Kapar power plant (Malaysia): What impacts on tropical zooplankton community?
2015
Chew, L.L. | Chong, V.C. | Wong, R.C.S. | Lehette, P. | Ng, C.C. | Loh, K.H.
Zooplankton samples collected before (1985–86) and after (2013–14) the establishment of Kapar power station (KPS) were examined to test the hypothesis that increased sea surface temperature (SST) and other water quality changes have altered the zooplankton community structure. Elevated SST and reduced pH were detected between before and after impact pairs, with the greatest impact at the station closest to KPS. Present PAHs and heavy metal concentrations are unlikely causal factors. Water parameter changes did not affect diversity but community structure of the zooplankton. Tolerant small crustaceans, salps and larvaceans likely benefited from elevated temperature, reduced pH and shift to a more significant microbial loop exacerbated by eutrophication, while large crustaceans were more vulnerable to such changes. It is predicted that any further rise in SST will remove more large-bodied crustacean zooplankton, the preferred food for fish larvae and other meroplankton, with grave consequences to fishery production.
Afficher plus [+] Moins [-]Trace elements and heavy metals in the Grand Bay National Estuarine Reserve in the northern Gulf of Mexico
2015
McComb, Jacqueline Q. | Han, Fengxiang X. | Rogers, Christian | Thomas, Catherine | Arslan, Zikri | Ardeshir, Adeli | Tchounwou, Paul B.
The objectives of this study are to investigate distribution of trace elements and heavy metals in the salt marsh and wetland soil and biogeochemical processes in the Grand Bay National Estuarine Research Reserve of the northern Gulf of Mexico. The results show that Hg, Cd and to some extent, As and Pb have been significantly accumulated in soils. The strongest correlations were found between concentrations of Ni and total organic matter contents. The correlations decreased in the order: Ni>Cr>Sr>Co>Zn, Cd>Cu>Cs. Strong correlations were also observed between total P and concentrations of Ni, Co, Cr, Sr, Zn, Cu, and Cd. This may be related to the P spilling accident in 2005 in the Bangs Lake site. Lead isotopic ratios in soils matched well those of North American coals, indicating the contribution of Pb through atmospheric fallout from coal power plants.
Afficher plus [+] Moins [-]Spatial and Short-Temporal Variability of δ13C and δ15N and Water-Use Efficiency in Pine Needles of the Three Forests Along the Most Industrialized Part of Poland
2015
Sensuła, Barbara M.
In this study, stable carbon and nitrogen isotope ratios in the samples of pine needles collected in 2013 and 2014 from heavily urbanized area in close proximity to point-source pollution emitters, such as a heat and power plant, nitrogen plant, and steelworks in Silesia (Poland), were analyzed as bio-indicators of contemporary environmental changes. The carbon isotope discrimination has been proposed as a method for evaluating water-use efficiency. The measurement of carbon and nitrogen isotopes was carried out using the continuous flow isotope ratio mass spectrometer. The isotope ratio mass spectrometer allows the precise measurement of mixtures of naturally occurring isotopes. The δ¹⁵N values were calibrated relative to the NO-3 and USGS34 international standards, whereas the δ¹³C values were calibrated relative to the C-3 and C-5 international standards. The strong year-to-year correlations between the δ¹³C in different sampling sites, and also the inter-annual correlation of δ¹⁵N values in the pine needles at each of the investigated sampling sites confirm that the measured δ¹³C and δ¹⁵N and also intrinsic water-use efficiency (iWUE) trends are representative of the sampling site. Diffuse air pollution caused the variation in δ ¹³C, δ¹⁵N, and iWUE dependent on type of emitter, the localization in the space (distance and direction) from factories and some local effect of other human activities. The complex short-term variation analysis can be helpful to distinguish isotopic fractionation, which is not an effect explainable by climatic conditions but by the anthropogenic effect. Between 2012 and 2014, an increase in iWUE is observed at leaf level.
Afficher plus [+] Moins [-]Tree Growth and Climate Relationship: Dynamics of Scots Pine (Pinus Sylvestris L.) Growing in the Near-Source Region of the Combined Heat and Power Plant During the Development of the Pro-Ecological Strategy in Poland
2015
Since the 1990s, the emission of pollutants was reduced in a majority of Polish and developing country factories whereas the level of energy production was similar to that prior to the 1990s. The conifer investigated in this study has grown for many years under the stress of industrial pollution. Despite this, the trees are preserved, to a large extent, sensitive to the natural climatic factors. We present a complex analysis of the climatic (sunshine, temperature, precipitation, humidity, and wind circulation) and anthropogenic factors influencing the radial increment dynamics of Scots pine (Pinus sylvestris L.) growing in the vicinity of the combined heat and power station in Łaziska (Poland). We analyzed the spatiotemporal distribution of growth reductions, the depth of reduction with respect to the distance from the emitter, the relationship between tree growth and climate during the industry development period and during proecological strategy application . Samples of carbon isotopic composition in pine needles from 2012 to 2013 were additionally determined. Pines series of 3 positions indicate that they have a similar sensitivity to most climatic elements of the previous and given year, but there is also a different rhythm between the studied populations of incremental growth of pines. The causes of diversity are due to the different types of habitat (site types) and industrial pollution. The variation in carbon stable isotopic composition in pine needles was connected with an increase of CO₂.
Afficher plus [+] Moins [-]Effect on the Photo-production of Dissolved Gaseous Mercury in Post-desulfurized Seawater Discharged from a Coal-Fired Power Plant
2015
Sun, Lumin | Lu, Bingyan | Yuan, Dongxing | Xue, Cheng
A high concentration of dissolved gaseous mercury (DGM) was detected in post-desulfurized waste seawater, which was discharged from a coal-fired power plant equipped with a seawater desulfurization system and which was located in a coastal area. A large amount of DGM was converted from other forms of mercury during transformation processes, such as photo-reduction. The present study targeted the photo-reduction of mercury and the effects of various environmental parameters on DGM production in the post-desulfurized seawater discharged. The results suggested that the photo-reduction of mercury was significantly induced under UV radiation, especially with UVB. The particulate mercury on suspended solids was easily photo-reduced and considered as an important source of DGM. It was confirmed that the suspended solids in post-desulfurized seawater could enhance the reduction process of mercury under UV radiation. The pseudo-first-order rate constants of DGM production, which were determined through the concentration gradient and trial methods, were 1.39 × 10⁻³ min⁻¹and 1.45 × 10⁻³ min⁻¹, respectively. The values showed no significant difference and were both much higher than the reported results, indicating that the photo-reduction of mercury in post-desulfurized seawater deserved more attention. In addition, the initial mercury level was observed when mixing the post-desulfurized seawater with fresh seawater, and this suggested that a significant amount of initial mercury would be produced when the post-desulfurized seawater was discharged into the adjacent sea area and thus becomes another considerable source of DGM.
Afficher plus [+] Moins [-]Thermal Impact from a Thermoelectric Power Plant on a Tropical Coastal Lagoon
2015
Cardoso-Mohedano, J. G. | Bernardello, R. | Sanchez-Cabeza, J. A. | Ruiz-Fernández, A. C. | Alonso-Rodriguez, R. | Cruzado, A.
Tropical coastal areas are sensitive ecosystems to climate change, mainly due to sea level rise and increasing water temperatures. Furthermore, they may be subject to numerous stresses, including heat releases from energy production. The Urias coastal lagoon (SE Gulf of California), a subtropical tidal estuary, receives cooling water releases from a thermoelectric power plant, urban and industrial wastes, and shrimp farm discharges. In order to evaluate the plant thermal impact, we measured synchronous temperature time series close to and far from the plant. Furthermore, in order to discriminate the thermal pollution impact from natural variability, we used a high-resolution hydrodynamic model forced by, amongst others, cooling water release as a continuous flow (7.78 m³ s⁻¹) at 6 °C overheating temperature. Model results and field data indicated that the main thermal impact was temporally restricted to the warmest months, spatially restricted to the surface layers (above 0.6 m) and distributed along the shoreline within ∼100 m of the release point. The methodology and results of this study can be extrapolated to tropical coastal lagoons that receive heat discharges.
Afficher plus [+] Moins [-]Adsorption of Cs from Water on Surface-Modified MCM-41 Mesosilicate
2015
Guo, Kai | Han, Fengxiang | Arslan, Zikri | McComb, Jacqueline | Mao, Xinyu | Zhang, Rong | Sudarson, Sinha | Yu, Hongtao
Cs is a common radionuclide present in nuclear wastes and released from nuclear power plant accidents. It is hard to be removed from water with traditional technology. The current study aimed at developing of efficient cost-effective adsorbent for removing Cs with modified MCM-41 with specific functional groups –SH. Mesoporous material MCM-41 was selected due to its large surface area and tunable pore structure. Functional –SH groups were grafted into the pores of MCM-41 to enhance its capability of selective adsorption of Cs from multi-element (Co, Sr) water solution. The adsorption results showed that the maximum adsorption capacity was 29.24 mg/g. Both Langmuir and Freundlich models described the adsorption processes of Cs, indicating co-existence of both monolayer and multilayer adsorption in the surface and inner pores of the materials. TEM, FTIR, and Raman spectroscopy analyses indicated that –SH groups were successfully bounded into the pores of MCM-41. The present study approved the surface functional modified MCM-41 which might be a good alternative candidate for cleaning up of radionuclide Cs from nuclear power plant accidents and relevant nuclear accident events.
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