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Contaminated Water (contaminated + water)
Selected AbstractsContinuing Progressive Deterioration of the Environment in the Aral Sea Region: Disastrous Effects on Mother and Child HealthACTA PAEDIATRICA, Issue 5 2001O Ataniyazova Scientists, non-governmental experts (NGOs) and governmental officials from the Central Asian Republics and an international group of invited scientists and NGO representatives participated in a workshop on the disastrous health problems in the Aral Sea Region. Various serious problems were reported in more than 20 presentations. Particular emphasis was put on the way in which adverse environmental factors such as contaminated water and food have contributed to the deterioration of human health, particularly that of mothers and children. Conclusion: There is an urgent request that the international community assists local scientists to develop programmes to improve the health of the population in the Aral Sea Region. [source] Quantification of Survival of Escherichia coli O157:H7 on Plants Affected by Contaminated Irrigation Water,ENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 6 2006A. M. Ibekwe Abstract Enterohemorrhagic E. coli O157: H7 (EHEC) is a major foodborne pathogen capable of causing diarrhea and vomiting, with further complications such as hemolytic-uremic syndrome (HUS). The aim of this study was to use the real-time PCR method to quantify the survival of Escherichia coli O157:H7/pGFP in phyllosphere (leaf surface), rhizosphere (volume of soil tightly held by plant roots), and non-rhizosphere soils (sand and clay) irrigated with contaminated water and compare the results obtained between real-time PCR method and conventional plate counts. The real-time PCR probe was designed to hybridize with the (eae) gene of E. coli O157:H7. The probe was incorporated into real-time PCR containing DNA extracted from the phyllosphere, rhizosphere, and non-rhizosphere soils irrigated with water artificially contaminated with E. coli O157:H7. The detection limit for E. coli O157:H7 quantification by real-time PCR was 2.3 × 103 in the rhizosphere and phyllosphere samples. E. coli O157:H7 survived longer in rhizosphere soil than the non-rhizosphere soil. The concentration of E. coli O157:H7/pGFP in rhizosphere soils was , 104 CFU/g in both soils at day 12 based on both plate count and real time PCR, with the clay soil significantly (P = 0.05) higher than the sandy soil. This data showed that E. coli O157H:7 can persist in the environment for more than 50 d, and this may pose some risk for both animal and human infection and provides a very significant pathway for pathogen recontamination in the environment. [source] Trout density and health in a stream with variable water temperatures and trace element concentrations: Does a cold-water source attract trout to increased metal exposure?ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 4 2009David D. Harper Abstract A history of hard-rock mining has resulted in elevated concentrations of heavy metals in Prickly Pear Creek (MT, USA). Remediation has improved water quality; however, dissolved zinc and cadmium concentrations still exceed U.S. Environmental Protection Agency water-quality criteria. Physical habitat, salmonid density, fish health, and water quality were assessed, and metal concentrations in fish tissues, biofilm, and macroinvertebrates were determined to evaluate the existing condition in the watershed. Cadmium, zinc, and lead concentrations in fish tissues, biofilm, and invertebrates were significantly greater than those at the upstream reference site and an experimental site farther downstream of the confluence. Fish densities were greatest, and habitat quality for trout was better, downstream of the confluence, where water temperatures were relatively cool (16°C). Measures of fish health (tissue metal residues, histology, metallothionein concentrations, and necropsies), however, indicate that the health of trout at this site was negatively affected. Trout were in colder but more contaminated water and were subjected to increased trace element exposures and associated health effects. Maximum water temperatures in Prickly Pear Creek were significantly lower directly below Spring Creek (16°C) compared to those at an experimental site 10 km downstream (26°C). Trout will avoid dissolved metals at concentrations below those measured in Prickly Pear Creek; however, our results suggest that the preference of trout to use cool water temperatures may supersede behaviors to avoid heavy metals. [source] Detection of Cryptosporidium parvum in lettuceINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2007John E. Moore Summary Human cryptosporidiosis has emerged as an important gastrointestinal infection in the 1990s as a result of the ingestion of mainly contaminated water and to a lesser extent foodstuffs containing the protozoan parasite, Cryptosporidium parvum. This pathogen has particular clinical significance for immunocompromised persons, including AIDS patients and cancer patients receiving toxic chemotherapeutic drug regimens. There have been a limited number of studies performed examining the occurrence of the parasite on vegetables, including lettuce. Detection rates are very dependent on the laboratory isolation technique employed and has ranged from 1.2% to 14.5%. Current best practice of laboratory recovery, isolation and detection methods include detergent removal, oocysts concentration by immunomagnetic separation, followed by a combination of immunofluorescent microscopy and a nested PCR approach. Employment of contaminated non-potable water in the production of vegetables, particularly lettuce, may represent an important potential source of entry of pathogens into food processing and the human food chain. Given that lettuce is an important constituent of hamburger dressing, and the size of the fast-food industry, where lettuce is an important constituent, horticultural producers of lettuce should therefore place special emphasis on developing suitable and efficient Hazard Analysis Critical Control Point strategies for the critical control of oocysts depending on the type of unit operation employed and vegetable being processed. This review aims to examine (i) the incidence of C. parvum in vegetables, particularly lettuce and (ii) laboratory detection methods for the isolation and identification of this parasite from lettuce. [source] Prevalence and potential link between E. coli O157:H7 isolated from drinking water, meat and vegetables and stools of diarrhoeic confirmed and non-confirmed HIV/AIDS patients in the Amathole District , South AfricaJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2008B.O. Abong'o Abstract Aim:, The current study investigated the prevalence and molecular relatedness between Escherichia coli O157:H7 isolated from water, meat and meat products and vegetables and from stools of confirmed and non-confirmed Human Immune Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) patients with diarrhoea. Methods and Results:, Culture-based and polymerase chain reaction techniques were used to identify E. coli O157:H7. Thirty-five per cent of meat products, 25·5% of water, 21·7% of vegetables as well as 56·5% and 43·5% of stools of confirmed and non-confirmed HIV/AIDS patients, respectively, were presumptively positive with E. coli O157. Molecular results indicated that 10·3%, 8·6% and 7·8% of the vegetables, water and meat products examined carried E. coli O157:H7, which had homologous fliCH7, rfbEO157 and eaeA genetic loci to the genes of some E. coli O157:H7 isolated from 12·2% and 8·8% of the stools of confirmed and non-confirmed HIV/AIDS patients, respectively. Conclusions:, Water, meat and meat products and vegetables are potential sources of E. coli O157:H7 that are potentially capable of causing diarrhoea in humans especially HIV/AIDS patients. Significance and Impact of the Study:, Great care should be exercised to ensure that water and foods consumed by HIV/AIDS patients are safe, as contaminated water and foods can cause secondary infections in these patients. [source] Isolation of Laribacter hongkongensis, a novel bacterium associated with gastroenteritis, from drinking water reservoirs in Hong KongJOURNAL OF APPLIED MICROBIOLOGY, Issue 3 2007S.K.P. Lau Abstract Aims:, Freshwater fish has been found to be the reservoir of Laribacter hongkongensis, a recently discovered bacterium associated with community-acquired gastroenteritis. However, little is known about the ecology of this bacterium in the aquatic environment. We carried out a surveillance study to investigate the presence of L. hongkongensis in water and freshwater fish from 10 drinking water reservoirs in Hong Kong. Methods and Results:, Using membrane filtration, L. hongkongensis was isolated from the waters of six reservoirs, with numbers ranging from 1 to 12 CFU l,1. Higher recovery rates were observed in summer and during days of higher water and ambient temperatures. Of 27 freshwater fish collected from the reservoirs, L. hongkongensis was recovered from the intestines of two fish, a Goldfish and a Nile tilapia. Overall, 35 different pulsed-field gel electrophoresis patterns are found among the 59 isolates recovered from water and the two isolates from freshwater fish. Conclusions:, The present report represents the first to demonstrate the presence of L. hongkongensis in natural water environments. Significance and Impact of the Study:, Although it is unlikely that treated, drinking water is an important source of L. hongkongensis -associated gastroenteritis, one should be aware of the possibility of other contaminated water as a source of human infection. [source] Acinetobacter bioreporter assessing heavy metals toxicityJOURNAL OF BASIC MICROBIOLOGY, Issue 5 2006Desouky Abd-El-Haleem Dr. This work was conducted to employ a whole cell-based biosensor to monitor toxicity of heavy metals in water and wastewater. An isolate of industrial wastewater bacterium, Acinetobacter sp. DF4, was genetically modified with lux reporter gene to create a novel bioluminescent bacterial strain, designated as DF4/PUTK2. This bioreporter can investigate the toxicity through light inhibition due to cell death or metabolic burden and the specific stress effects of the tested soluble materials simultaneously. The use of Acinetobacter DF4/PUTK2 as a bioluminescent reporter for heavy metal toxicity testing and for the application of wastewater treatment influent toxicity screening is presented in this study. Among eight heavy metals tested, the bioluminescence of DF4/PUTK2 was most sensitive to Zn, Cd, Fe, Co, Cr followed by Cu in order of decreasing sensitivity. The same pattern of sensitivity was observed when several contaminated water and wastewater effluents were assayed. This work suggested that luxCDABE -marked Acinetobacter bacterium DF4/PUTK2 can be used to bioassay the ecotoxicity of wastewater and effluent samples contaminated with heavy metals. Using this assay, it is possible to pre-select the more toxic samples for further chemical analysis and to discard wastewater samples with low or no inhibition because they are not toxic to the environment. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Photocatalytic degradation of methyl tert -butyl ether (MTBE) in contaminated water by ZnO nanoparticlesJOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 11 2008Akbar Eslami Abstract BACKGROUND: Over the past several decades methyl tert -butyl ether (MTBE) as additive to gasoline, intended to either boost ratings of fuel or to reduce air pollution, has been accepted worldwide. Since MTBE has high water solubility, the occurrence of fuel spills or leaks from underground storage tanks or transferring pipeline has led to the contamination of natural waters. In this study the degradation of aqueous MTBE at relatively high concentrations was investigated by a UV-visible/ZnO/H2O2 photocatalytic process. The effects of important operational parameters such as pH, amount of H2O2, catalyst loading and irradiation time were also investigated. Concentration of MTBE and intermediates such as tert -butyl formate and tert -butyl alcohol were measured. RESULTS: Time required for complete degradation increased from 20 to 150 min when the initial concentration was increased from 10 to 500 mg L,1. The first-order rate constants for degradation of MTBE were estimated to be 0.183,0.022 min,1 as the concentration increased from 10 to 500 mg L,1. Study of the overall mineralization monitored by total organic carbon analysis showed that at an initial concentration of 100 mg L,1 MTBE complete mineralization was obtained after 100 min under UV-visible/ZnO/H2O2 photocatalysis. CONCLUSION: The data presented in this paper clearly indicated that UV-visible/ZnO/O2 as an advanced oxidation process provides an efficient treatment alternative for the remediation of MTBE-contaminated waters. Copyright © 2008 Society of Chemical Industry [source] Application of heterogeneous adsorbents in removal of dimethyl phthalate: Equilibrium and heatAICHE JOURNAL, Issue 10 2010Jun Wu Abstract Aminated resin (NDA-101) and oxidized resin (NDA-702) were synthesized to remove Dimethyl phthalate (DMP) from the contaminated water. The equilibrium and heat properties in the course of adsorption process were examined and compared with two commercial heterogeneous adsorbents, namely an acrylic ester resin (Amberlite XAD-7) and a coal-based granular activated carbon (AC-750). The associated equilibrium isotherms can be well fitted by Freundlich equation and the adsorption capacities for DMP followed the order: NDA-702 > NDA-101 > AC-750 > XAD-7. The surface of XAD-7 was demonstrated to be relatively homogeneous through surface energy heterogeneity analysis, offering the sole hydrogen bonding interaction. Contrarily, heterogeneous surface of oxidized resins NDA-702 and the aminated resins NDA-101 exhibited a promising adsorption capacity and affinity toward DMP probably derived by multiple hydrogen bonding, ,,, stacking, and micropore filling interactions. © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Use of repetitive DNA sequences to determine the persistence of enteropathogenic Escherichia coli in vegetables and in soil grown in fields treated with contaminated irrigation waterLETTERS IN APPLIED MICROBIOLOGY, Issue 5 2006K. Ibenyassine Abstract Aims:, Fresh fruits and vegetables are increasingly recognized as vectors for food-borne illness. On farm contamination through contaminated irrigation water is considered likely source of the pathogen for several outbreaks. The purpose of this study is to investigate the possible similarity of strains of Escherichia coli isolated from the soil and vegetables irrigated by treated wastewater. Methods and Results:, Seventy-five strains of enteropathogenic Escherichia coli isolated from vegetables, soil and irrigation water were tested for sensitivity to antibiotics and shown to be sensitive. The result of enterobacterial repetitive intergenic consensus (ERIC)-PCR shows similarities between analysed strains isolated from the three different samples. Moreover strains of E. coli isolated from vegetables over different periods of time have the same ERIC-PCR profile. Conclusions:, The isolated strains of enteropathogenic E. coli can persist in soil and in vegetables growing in fields treated with contaminated irrigation water for an extended period of time. Significance and Impact of the Study:, Contaminated irrigation water can transport pathogenic bacteria, which persists in the soil for a long period of time and contaminates the vegetables growing in the field irrigated by this contaminated water. [source] The phage-driven microbial loop in petroleum bioremediationMICROBIAL BIOTECHNOLOGY, Issue 4 2010Eugene Rosenberg Summary During the drilling process and transport of crude oil, water mixes with the petroleum. At oil terminals, the water settles to the bottom of storage tanks. This drainage water is contaminated with emulsified oil and water-soluble hydrocarbons and must be treated before it can be released into the environment. In this study, we tested the efficiency of a continuous flow, two-stage bioreactor for treating drainage water from an Israeli oil terminal. The bioreactor removed all of the ammonia, 93% of the sulfide and converted 90% of the total organic carbon (TOC) into carbon dioxide. SYBR Gold staining indicated that reactor 1 contained 1.7 × 108 bacteria and 3.7 × 108 phages per millilitre, and reactor 2 contained 1.3 × 108 bacteria and 1.7 × 109 phages per millilitre. The unexpectedly high mineralization of TOC and high concentration of phage in reactor 2 support the concept of a phage-driven microbial loop in the bioremediation of the drainage water. In general, application of this concept in bioremediation of contaminated water has the potential to increase the efficiency of processes. [source] | |||||||||||||