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Chemistry of the Urauchi River Water in Iriomote Island National Park, Okinawa, Japan Full text
2009
Ishiki, Maki | Sakihama, Hideaki | Agata, Seizen | Tokuyama, Akira
The chemical characteristics of the Urauchi River water in Iriomote Island National park, Okinawa, Japan have been studied. Concentrations of PO₄ ³⁻, NO₂ ⁻, and NH₄ ⁺ were barely detectable. We compared the concentration ratios of Mg²⁺/Na⁺, HCO₃ ⁻/Na⁺, and Ca²⁺/Na⁺ in the Urauchi River to those of 60 large rivers in the world and indicated that the chemical composition of the river is most likely formed by the binary mixing of sea salt components and silicate rock weathering components. Although rock weathering in the catchments area is driven by both H₂CO₃ and H₂SO₄, the role of H₂CO₃ is dominant. The percentages of the concentration of each cation in the river water are almost the same as those of other rivers with drainage areas consisting of silicate rock and sandstone. Thus, the Urauchi River shows the typical chemical characteristics of a river in a silicate rock area that includes sandstone.
Show more [+] Less [-]Characterization of E1 Kraft Mill Effluent by Toxicity Identification Evaluation Methodology Full text
2009
Reyes, F. | Chamorro, S. | Yeber, M. C. | Vidal, G.
In order to recover and reuse water in the Kraft mill process, evaluation of separate streams is required to identify toxic compounds or microcontaminants. The stage E1 Kraft effluent, corresponding to the first extraction step of the bleaching Kraft mill process, provides the main toxic compounds found in the final process effluent. This paper uses the toxicity identification evaluation (TIE) procedure for the physicochemical and ecotoxicological characterization of the E1 Kraft effluent. To distinguish the most important toxic compounds, a physicochemical characterization and Phase I of the TIE procedure were performed. The acute toxic effect of the E1 Kraft effluent and treated fraction was performed on Daphnia magna. Results show that untreated E1 Kraft effluent exerts an acute toxic effect on D. magna (24 h LC₅₀ = 27.6%), where the E1 Kraft effluent is characterized by pH 10.5, chemical organic demand (COD) 1,348.8 mg/l, and biological organic demand (BOD₅) 397.5 mg/l, while total phenolic compounds and color are 853.7 mg/l and 0.204 1 x 1 cm, respectively. Additionally, Cu⁺² (0.51 mg/l) and Fe⁺² (0.64 mg/l) were detected. With respect to different treatments, our results indicate that activated carbon, anionic and cationic exchange treatments were able to reduce more that 45% of E1 Kraft effluent's acute toxicity and that the ethylenediaminetetraacetic acid treatment was able to reduce the E1 Kraft effluent's acute toxicity to around 75% and the Cu⁺² concentration to 0.019 mg/l. Moreover, specific analysis of heavy metals and organic compounds by GC-MS show that the main compound responsible for the toxicity was Cu⁺², whose tolerance level on D. magna of the 0.12 mg/l.
Show more [+] Less [-]Economic and Environmental Benefits of Using Hardwood Sawmill Waste as a Raw Material for Particleboard Production Full text
2009
Setunge, Sujeeva | Wong, Kee Kong | Jollands, Margaret
Annually, sawmills and other wood-processing factories generate a significant amount of scrap materials which are sent to landfills or incinerated. The amount of residue generated in Australia annually is estimated at 200,000 tonnes. A research project conducted at RMIT University explored utilizing these waste materials as particleboard furnish. The research team has now established a methodology for making particleboard in the laboratory using 100% hardwood sawmill residues, developing a particleboard product made in the laboratory which has acceptable mechanical properties and density profiles in accordance with the Australian Standards. However, this board product has some perceived issues which have been hindering ready commercial uptake. The current product requires a 10% higher resin load, has a 10% higher board density, and requires 10% longer pressing times compared to normal softwood particleboard. The paper presents an analysis of the current production process of particleboard to investigate the economic feasibility of particleboard production using hardwood sawmill residues. A major challenge in the analysis is converting the environmental benefit of utilizing large quantities of sawmill residue to a monetary term. Investigation of the global impact of particleboard by considering emission of carbon dioxide to the atmosphere is also included. A comparison is presented between different methods of disposing wood residues to understand the environmental benefit of using hardwood residue in particleboard.
Show more [+] Less [-]Interspecific Variation of Heavy Metal Concentrations in the Different Parts of Tropical Intertidal Bivalves Full text
2009
Edward, Franklin Berandah | Yap, Chee Kong | Ismail, Ahmad | Tan, Soon Guan
The concentrations of Cd, Cu, Fe, Ni, Pb and Zn in the different parts of six bivalves species were determined. From the study conducted, it was found that the byssus of Perna viridis, Scpharca broughtonii and Trisidos kiyonoi; the gill of Polymesoda erosa and Donax faba; and the foot of Gelonia expansa were highly accumulative of Cu. High levels of Cd were found in the gills of Scpharca broughtonii and the byssus of Trisidos kiyonoi; and also the shells of the four remaining bivalve species. As for Zn, the mantles of P. erosa and T. kiyonoi, and the gills of D. faba, G. expansa and S. broughtonii were highly accumulative of Zn. High level of Pb and Ni were found in the shells of all the species which indicated that the shells of the bivalves were highly accumulative of Pb and Ni. Elevated levels of Fe however were found in the different parts of the bivalve since Fe is an essential metal in metabolic activities and an abundant element in nature. The heavy metals in the total tissues and the different soft tissues of the bivalves were compared with the maximum permissible limits set by five different countries. From the comparison, it was found that most of the bivalves contained metal concentrations which were below the maximum permissible limits and should pose no toxicological risk to consumers.
Show more [+] Less [-]A Survey of Organotin Compounds in the Northern Adriatic Sea Full text
2009
Milivojevič Nemanič, Tadeja | Milačič, Radmila | Ščančar, Janez
The extent of pollution with organotin compounds was investigated in water, sediment and bivalve mussels (Mytilus galloprovincialis) from the Northern Adriatic Sea. Butyl-, phenyl- and octyltin species were quantified after extraction and derivatisation by gas chromatography-mass spectrometry in a total of 99 samples from the period from 2000 to 2006. The accuracies of the analytical procedures were checked by spiking of unpolluted water samples and by the analysis of standard reference materials (harbour sediment PACS-2 and mussel tissue ERM-CE 477). Among organotin species analysed in samples butyltins were the predominant. Tributyltin was found to be present in the highest concentrations, suggesting its recent input into the marine environment. Butyltins were detected at all sites surveyed (sum of butyltins was up to 718 ng Sn L⁻¹, 3,552 ng Sn g⁻¹ d.w. and 9,991 ng Sn g⁻¹ d.w. in water, sediment and mussel samples, respectively), phenytins in much lower concentrations (up to 31 ng Sn L⁻¹, 326 ng Sn g⁻¹ d.w. and 442 ng Sn g⁻¹ d.w. in water, sediment and mussel samples) and to a much smaller extent, while octyltins were not detected at any location. The spatial distribution of tributyltin was closely related to boating, with the highest concentrations found in marinas (up to 586 ng Sn L⁻¹ for water samples, 1,995 ng Sn g⁻¹ d.w. for sediment and 6,434 ng Sn g⁻¹ d.w. for mussel samples). The temporal distribution clearly indicates a decrease of organotin pollution at all sites.
Show more [+] Less [-]Statistical Analysis of Metal Concentrations in a Sediment Core to Reveal Influences of Human Activities on Atmospheric Environment for 200 Years Full text
2009
Katahira, Kenshi | Ishitake, Miho | Moriwaki, Hiroshi | Yamamoto, O (Osamu) | Fujita, Tadao | Yamazaki, Hideo | Yoshikawa, Shusaku
Metal concentrations in a sediment core from a moat outside Osaka Castle in Japan were measured by ICP-MS following a microwave extraction method. Concentrations of metals in the sediment core samples peaked around 1945 when the World War II ended. This is in part due to great air raids on Osaka. In cluster analysis using metal concentrations, the fractions of sediment core samples were classified into two groups, representing natural sources (1795-1915) and anthropogenic sources (1922-1976), respectively. Results of lead isotope ratios also showed the anthropogenic influences from 1915 by changing the ratio values compared to those of natural sources. In addition, several components contributing to metal concentrations were identified by principal component analysis. The main component was controlled by natural sources and a decrease of the component score corresponded to an increased influence from anthropogenic sources. The largest impact of anthropogenic sources was shown around 1945.
Show more [+] Less [-]Factors Associated with Well-to-Well Variation in Nitrate Concentration of Groundwater in a Nitrate-Polluted District in Miyakonojo Basin, Southern Kyushu, Japan Full text
2009
Sugimoto, Yasuhiro | Toyomitsu, Yukio | Muto, Isao | Hirata, Masahiko
This study monitored nitrate levels in well water and analyzed their association with well attributes (physicochemical parameters of water, location, livestock farming conditions) in a nitrate-polluted, animal industry district in central Miyakonojo Basin, southern Kyushu, Japan, to characterize the nitrate status of groundwater in the district. Water quality varied considerably among the wells, with nitrate-N concentration and natural nitrogen-15 abundance in nitrate-N (δ¹⁵N-NO₃) ranging from 1.1-44.6 mg L⁻¹ and 4.2-17.8[per thousand], respectively. There was a significant positive correlation between nitrate-N concentration and δ¹⁵N-NO₃. Nitrate-N concentration was higher in wells located at higher elevations, having larger areas of livestock barns within a 100-m radius and with higher animal populations. Wells in pig farms showed a higher nitrate tendency than those in the other situations (cattle farm, poultry farm, non-livestock farm and non-farmer). The results show that the nitrate status of groundwater in the district has not been drastically changed since 1996, and the nitrate in the wells is of multiple origins (e.g. chemical fertilizer, animal wastes) with a tendency for higher contribution of animal wastes in more heavily polluted wells. The results also highlight a need for further regular monitoring of groundwater quality in the district particularly for wells; (1) located at higher elevations, (2) with a large area of livestock barns nearby, (3) in farms with a high animal population and/or (4) in pig farms.
Show more [+] Less [-]Influence of Different Pretreatments on Anaerobically Digested Sludge Characteristics: Suitability for Final Disposal Full text
2009
Carballa, Marta | Omil, Francisco | Lema, Juan M.
The debate on sludge recycling and disposal has been recently a target of growing interest due to the expressed concern about the potential risks of its agricultural use on human health and the environment. This fact has led to revisions in government policy and regulations and many novel treatment processes have been proposed in order to make the recycling and reuse of sewage sludge sustainable. In this work, the use of some pretreatments (alkaline, thermal, and ozonation) combined with conventional anaerobic digestion has been assessed on digested sludge quality in terms of pathogens, dewatering properties, heavy metals, and organic pollutants. All pretreatments proved to be efficient to reach the requirements proposed in the Working Document on Sludge prepared by the European Commission (CEC, Council Directive of 27 April 2000 on Working Document on Sludge--third draft. Brussels: European Commission DG Environment. Retrieved from http://ec.europa.eu/environment/waste/sludge/pdf/sludge_en.pdf, 2000a) and also those established by the U.S. Environmental Protection Agency (EPA, Standards for the disposal and utilization of sewage sludge, part 503. Retrieved from http://www.epa.state.il.us/public-notices/2004/lincoln-trails-mhp/draft-permit.pdf, 1993).
Show more [+] Less [-]Implications of Uncertainty in a Pre-treatment Dataset when Estimating Treatment Effects in Paired Catchment Studies: Phosphorus Loads from Forest Clear-cuts Full text
2009
Laurén, A. | Heinonen, J. | Koivusalo, H. | Sarkkola, S. | Tattari, S. | Mattsson, T. | Ahtiainen, M. | Joensuu, S. | Kokkonen, T. | Finér, L.
Implications of Uncertainty in a Pre-treatment Dataset when Estimating Treatment Effects in Paired Catchment Studies: Phosphorus Loads from Forest Clear-cuts Full text
2009
Laurén, A. | Heinonen, J. | Koivusalo, H. | Sarkkola, S. | Tattari, S. | Mattsson, T. | Ahtiainen, M. | Joensuu, S. | Kokkonen, T. | Finér, L.
Estimates of increased nutrient export caused by forest clear-cuttings are mostly based on long-term paired catchment studies, where the treatment effect is calculated using pre-treatment dataset regression and post-treatment records of nutrient loads. In these studies uncertainty in the regression between the pre-treatment loads from the control and from the treatment catchments is typically neglected, even though it affects determination of the magnitude and duration of the treatment effect. This uncertainty is described in terms of variance in regression coefficients and residuals. The aim was to study how uncertainty in a pre-treatment dataset is propagated to estimates of the treatment effects using two sets of paired catchment data in eastern Finland, where the total phosphorus loads following forest clear-cutting and site preparation were investigated. The results showed that neglecting the uncertainty in the pre-treatment data did not change the conclusions when the treatment effect was strong enough. However, when the treatment effect was small, neglecting the uncertainty in the pre-treatment dataset easily leads to over-interpretation of the results. The uncertainty in a pre-treatment dataset should be taken into account in the paired catchment studies in order to avoid bias in the estimation of management effects on the loads.
Show more [+] Less [-]Implications of uncertainty in pre-treatment dataset on estimation of treatment effects from paired catchment studies: loads of phosphorus from forest clear-cuts Full text
2009
Laurén, A. | Heinonen, J. | Koivusalo, H. | Sarkkola, S. | Tattari, S. | Mattsson, T. | Ahtiainen, M. | Joensuu, S. | Kokkonen, T. | Finér, L. | Metsäntutkimuslaitos
The Screening of River Water for Immunotoxicity Using an In Vitro Whole Blood Culture Assay Full text
2009
Pool, Edmund J. | Magcwebeba, Tandeka U.
The acquired immunity consists of two pathways namely the humoral immunity that defends the host against extracellular pathogens such as bacteria and the cell-mediated immunity that defends the host against intracellular pathogens such as Mycobacterium tuberculosis and viruses and also against cancers. The aim of this study is to determine the effects of river water collected from pristine and contaminated sites along the Eerste River, South Africa on inflammation, humoral and acquired immune pathways. Hydrophobic extracts were prepared from water collected at contaminated and pristine sites. Inflammatory activity was determined by measuring interleukin (IL)-6 levels synthesized by whole blood after incubation with the extracts. For determining the effects on acquired immunity, phytohemagglutinin stimulated whole blood from healthy volunteers was incubated with extracts. The effect on humoral immunity was determined using IL-10 as biomarker, while interferon-gamma was used as biomarker for cell-mediated immunity. The results obtained show that water from the sites downstream from human activity induced IL-6, a biomarker of inflammation. Extracts collected from a site downstream from an informal housing settlement suppressed biomarkers of both humoral and cell-mediated immunity. Water from sites impacted by human activity can potentially suppress the acquired immune system and this can pose a health risk to people using this water source. Studies must be done to investigate the long-term effects of the contaminated water on animals in vivo.
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