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Formation of chlorinated disinfection by-products in viticulture
2009
Barhorst, Jan Bernd | Kubiak, Roland
Background, aim and scope The use of sodium hypochlorite (HYP) in viticulture results in effluents which are contaminated with halogenated substances. These disinfection by-products (DBPs) can be quantified as group parameter 'adsorbable organic halogens' (AOX) and have not been determined in effluents of viticulture yet. The substances that are detected as AOX are unknown. The AOX can be composed of harmless substances, but even toxic contaminants. Thus, it is impossible to assess ecological impacts. The aim of this study is to determine the quantification of AOX and DBPs after the use of HYP. This will be helpful to reduce environmental pollution by AOX. Materials and methods The potential of HYP to generate AOX was determined in laboratory-scale experiments. Different model solutions were treated with HYP according to disinfection processes in viticulture and conditions of AOX formation in effluents were simulated. AOX were quantified using the flask-shaking method and identified DBPs were investigated by gas chromatography-mass spectrometry. Results Treatment with HYP resulted in the formation of AOX. The percentage conversion of HYP to AOX was up to 11%. Most important identified DBPs in viticulture are chloroform, dichloroacetic acid and trichloroacetaldehyde. In addition, the formation of carbon tetrachloride (CT), 1,1,1-trichloropropanone, 2,4-dichlorobenzoic acid and 2-chloro-/2,4-dichlorophenylacetic acid was investigated. It was demonstrated that reaction temperature, concentration of HYP and type of organic matter have important influence on the formation of chlorinated DBPs. Discussion The percentage conversion of HYP to AOX was similar to other published studies. Although a correlation of single compounds and AOX is difficult, chloroform was the predominant AOX. Generation of the volatile chloroform should be avoided due to possible adverse effects. The generation of dichloroacetic acid is of minor importance on account of biodegradation. Trichloroacetaldehyde and 1,1,1-trichloropropanone are weak mutagens and their formation should be avoided. Conclusions The generation of AOX and chlorinated DBPs can be minimised by reducing the concentrations of the organic materials in the effluents. The removal of organic matter before disinfection results in a decreased formation of AOX. HYP is an effective disinfectant; therefore, it should be used at low temperatures and concentrations to reduce the amount of AOX. If possible, disinfection should be accomplished by the use of no chlorine-containing agents. By this means, negative influences of HYP on the quality of wine can also be avoided. Recommendations and perspectives Our results indicate that HYP has a high potential to form AOX in effluents of viticulture. The predominant by-products are chloroform, dichloroacetic acid and trichloroacetaldehyde. In further research, wastewaters from a winery and the in- and outflows of two sewage treatment plants were sampled during vintage and analysed. These results will be discussed in a following paper.
Show more [+] Less [-]Phosphine in the Lower Atmosphere of Qingdao—A Coastal Site of the Yellow Sea (China)
2009
Li, Jian-Bing | Zhang, Gui-Ling | Zhang, Jing | Liu, Su-Mei | Ren, Jing-Ling | Hou, Zhong-Xin
Gaseous phosphine (PH₃) in the inshore atmosphere was observed from October 2005 to August 2006 at a coastal site of the Yellow Sea in China. The concentration of PH₃ ranged from 0.01 to 14.86 ng m⁻³ with an average of 1.14 ng m⁻³. The concentration showed a diurnal variation in PH₃ with the peak occurring at morning and the lowest point at noon. An obvious seasonal variation of atmospheric PH₃ was found, with the PH₃ levels in the summer higher than those in the winter. The PH₃ levels in the atmosphere were apparently affected by temperature, radiation, sources, and other meteorological factors. The data indicate that PH₃ can be transported between the terrestrial and inshore atmosphere of Qingdao and the Yellow Sea or the East China Sea in both directions. The study increases evidence that PH₃ participates within the global biogeochemical phosphorus cycle in P transport from land and inshore waters to the sea where commonly P is scarce and where PH₃ inflow could be of important.
Show more [+] Less [-]Phosphorus Fractionation in Sediment Cores Collected In 2005 Before and After Onset of an Aphanizomenon flos-aquae Bloom in Upper Klamath Lake, OR, USA
2009
Simon, Nancy S. | Lynch, Dennis | Gallaher, Thomas N.
We tested the hypothesis that there would be measurable losses of phosphorus (P) from surficial sediments of Upper Klamath Lake (UKL), Oregon, if sediments were a source of P during an algal bloom. We compared concentrations of total and forms of P at various depths in cores collected before and after the onset of a large Aphanizomenon flos-aquae bloom. Concentrations of inorganic P were determined in extraction solutions of MgCl₂ (1 M, pH 8), citrate-dithionite-bicarbonate, and 1 M HCl. Sediments below 2 cm were dominated by residual P which is defined as total P minus inorganic P. During the study period, data from the top 2-cm of sediment indicated (a) significant decrease in total P concentration, primarily associated with iron oxyhydroxides at one site, and (b) significant increase in total P concentration associated with residual P at a second site. Data from two other sites indicated no net changes in concentrations of total P.
Show more [+] Less [-]Glucosinolate Profiles of Arabidopsis thaliana in Response to Cadmium Exposure
2009
Sun, Xiumei | Zhang, Jixiu | Zhang, Haijun | Zhang, Qing | Ni, Yuwen | Chen, Jiping | Guan, Yafeng
The influence of cadmium on growth, cadmium accumulation, composition, and content of glucosinolates was investigated in Arabidopsis thaliana after 4 weeks of growth in hydroponics. Accumulation of 3,820 and 321 μg Cd g⁻¹ dry weight in the roots and leaves of A. thaliana, respectively, exposed to 50 μM Cd. Cadmium treatment significantly decreased the total concentration of glucosinolates both in the leaves and roots. Cd-induced alteration of total glucosinolate content in the roots was mainly due to the decrease of indolyl-glucosinolates. In the Cd treatment leaves, significant decreases were, respectively, detected for glucoibervirin and 4-methoxyglucobrassicin (P < 0.01), while other glucosinolate levels did not decrease significantly. In response to cadmium, the three indolyl-glucosinolates all showed significant decreases in the roots. The distinctive influence of cadmium on glucosinolate profiles in Cd-sensitive A. thaliana may be of great ecological importance, decreasing the resistance to phytophage attack. Taken together, our data is discussed in relation to jasmonic acid and salicylic acid as possible molecules that modulate the alteration of glucosinolate profiles in response to cadmium. The similar effects of Cd treatment on the levels of individual glucosinolates in leaves and roots were observed at higher-concentration cadmium treatment (100 μM Cd).
Show more [+] Less [-]Treatment of Stormwater using Fibre Filter Media
2009
Johir, M. A. H | Lee, J. J | Vigneswaran, S | Kandasamy, J | Shaw, K
In this study, a high-rate fibre filter was used as a pre-treatment to stormwater in conjunction with in-line flocculation. The effect of operating the fibre filter with different packing densities (105, 115 and 125 kg/m³) and filtration velocities (20, 40, 60 m/h) with and without in-line flocculation was investigated. In-line flocculation was provided using 5, 10 and 15 mg/L of ferric chloride (FeCl₃·6H₂O). The filter performance was studied in terms of pressure drop (ΔP), solids removal efficiency, heavy metals (total) removal efficiency and total organic carbon (TOC) removal efficiency. It is found that the use of in-line flocculation at a dose of 15 mg/L improved the performance of fibre filter as measured by turbidity removal (95%), total suspended solids reduction (98%), colour removal efficiency (99%), TOC removal (reduced by 30-40 %) and total coliform removal (93%). The modified fouling index reduced from 750-950 to 12 s/L² proving that fibre filter can be an excellent pre-treatment to membrane filtration that may be consider as post-treatment. The removal efficiency of heavy metal was variable as their concentration in raw water was small. Even though the concentration of some of these metals such as iron, aluminium, copper and zinc were reduced, others like nickel, chromium and cadmium showed lower removal rates.
Show more [+] Less [-]Nickel Uptake and its Effect on Some Nutrient Levels, Amino Acid Contents and Oxidative Status in Matricaria chamomilla Plants
2009
Kováčik, Jozef | Klejdus, Bořivoj | Hedbavny, Josef | Bačkor, Martin
The effect of nickel (Ni) excess on selected aspects of chamomile (Matricaria chamomilla L.) metabolism was studied. Water-soluble Ni represented 27%, 46%, and 47%, and the methanol-soluble fraction 54%, 70%, and 88% of total shoot Ni content after 10 days of treatments with 3, 60, and 120 μM Ni, respectively. “Intra-root” Ni content represented 72% (3 μM), 96% (60 μM), and 78% (120 μM) of total root Ni. Leaf rosettes treated with 120 μM contained 137 μg Ni g⁻¹ DW after 10 days of treatment. The highest Ni concentration particularly affected the content of mineral nutrients (e.g., decrease of K and increase of Fe) and activity of selected antioxidative enzymes (increase of ascorbate peroxidase and guaiacol peroxidase activities). Malondialdehyde accumulation was not influenced (measured in methanol extracts). Among 17 detected free amino acids, accumulation of histidine, proline, methionine, and cysteine was most distinct in the leaf rosettes and/or roots, indicating their involvement in Ni detoxification. Lower Ni toxicity in comparison to previously tested metals is also discussed.
Show more [+] Less [-]Photocatalytic Decolorization of Commercial Acid Dyes using Solar Irradiation
2009
Dias, Márlen G. | Azevedo, Eduardo B.
This work investigates the solar heterogeneous photocatalytic degradation of three commercial acid dyes: Blue 9 (C.I. 42090), Red 51 (C.I. 45430), and Yellow 23 (C.I. 19140). TiO₂ P25 from Degussa was used as the photocatalyst. The dyes were completely degraded within 120 min of treatment in the following increasing order of removal rate: Blue 9 < Yellow 23 < Red 51. The photocatalytic color removal process was well described by a two-first-order in-series reaction, followed by another first-order reaction. Photolytic experiments showed that this process is quite inefficient and highly selective towards Red 51 only. The dyes' solution was completely decolorized and organic matter removals up to 99% were achieved with photocatalysis. The lack of selectivity and the possibility of using solar light to excite the photocatalyst are promising results regarding the feasibility of this technology.
Show more [+] Less [-]Nutrient Pollution in Laucala Bay, Fiji Islands
2009
Singh, Sarabjeet | Aalbersberg, W. G. L. | Morrison, R. J.
The Laucala Bay coastal system was investigated from 2003 to 2005 to evaluate the changes in water quality (nutrients) after improvements in sewage effluent quality from Kinoya sewage treatment plant (KSTP), whose output is discharged into the bay. The oxidized nitrogen (NO x -N) values averaged 1.31 µM, but varied from 0.76 to 3.77 µM, and the filterable reactive phosphate or orthophosphate (FRP) averaged 0.77 µM, ranging from 0.24 to 2.37 µM. The mean concentrations of NO x -N and FRP, respectively, were two and ten times higher than concentrations found in unpolluted sites in Fiji. Based on these values and NH₃ concentrations from parallel studies, Redfield ratio estimates suggest that primary productivity of the bay is N limited. No significant decrease in concentration of both NO x -N and FRP was found in Laucala Bay waters during the present investigation compared to concentrations found in two previous studies. This indicates that KSTP effluent may be only a minor source of nutrients into the bay, and to protect the Laucala Bay ecosystem from increasing nutrient pollution, there is a need to control nutrient input from other major point and nonpoint sources.
Show more [+] Less [-]Simulated Summertime Regional Ground-Level Ozone Concentrations over Greece
2009
Poupkou, Anastasia | Melas, Dimitrios | Ziomas, Ioannis | Symeonidis, Panagiotis | Lisaridis, Iraklis | Gerasopoulos, Evangelos | Zerefos, Christos
Ground-level ozone concentrations were estimated for Greece during a summer period of the year 2000 using the regional air quality model UAM-V off-line coupled with the mesoscale meteorological model MM5. An anthropogenic NOx, NMVOCs and CO emission inventory and biogenic NMVOCs emission data were used to support model simulations. The evaluation analysis indicates a quite satisfactory model performance in reproducing ozone levels. The simulated mean ozone concentrations are above the 32-ppb EU phytotoxicity limit over almost all continental and maritime areas of Greece. Over the greater part of the country, the background mean ozone levels range from 40 to 55 ppb. Ozone values higher than the 55-ppb EU human health protection limit reaching 60 ppb dominate part of the southern Aegean Sea that is influenced by the Athens urban plume. In the areas where anthropogenic emission densities are high, the mean ozone levels vary between 20 and 40 ppb. Over the greater part of Greece, the simulated mean daily maximum ozone concentrations range from 50 to 65 ppb. More enhanced maximum ozone concentrations up to 95 ppb mainly dominate over the greater areas of the two largest Greek urban centres (Athens and Thessaloniki) and over the continental and maritime areas south of Athens which are under the influence of the urban plume.
Show more [+] Less [-]Chemical Composition of PM₁₀ and PM₂.₅ and Seasonal Variation in South Brazil
2009
Teixeira, Elba Calesso | Meira, Lindolfo | Santana, Eduardo Rodrigo Ramos de | Wiegand, Flavio
This paper presents experimental data on particulate matter (PM₁₀ and PM₂.₅) in the atmosphere of Candiota--South Brazil. Samples were collected using stacked filter units equipped with polycarbonate filters, which separate particles into two fractions: coarse 10-2.5 μm and fine <2.5 μm. The particulate matter was collected from January 2003 to September 2004 at three sampling sites: Acegua, 8 de Agosto, and Três Lagoas. The collected material was analyzed for Na, Mg, Al, Si, S, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br, Mo, Hg, and Pb, using particle-induced X-ray emission technique. Seasonal variation of the chemical elements with the size fraction was assessed. The elements K, Ca, Si, Ti, Fe, and Mn showed similar seasonal variability in the fine and coarse fractions with a low enrichment factor (<1.0) in both fractions, except for Mn and K, indicating common sources (soil dust, fly ash). Chemical species showing seasonal variability and high values of enrichment factor in fine fractions may indicate an anthropogenic origin.
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