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Pollution Indicators in Gaborone Industrial Effluent  [PDF]
V. Emongor,E. Nkegbe,B. Kealotswe,I. Koorapetse
Journal of Applied Sciences , 2005,
Abstract: The objective of this study was to determine pollution indicators in and around Gaborone industrial effluent, generate relevant baseline information on industrial effluents; and determine the major sources of industrial pollution in Gaborone, Botswana. The results of the study showed that effluent quality discharged by the four different industry types in Gaborone, Botswana, differed significantly. Brewery, chemical, paints, food and beverage industries had significantly high COD, BOD and suspended solids above the maximum permissible limits. While the chemical and paints industries could be a potential source of lead pollution in Gaborone. Temperature and acidity generally were not a problem for industrial effluents. The pharmaceutical industries met all the maximum and minimum guidelines for wastewater discharge. COD, BOD, suspended solids and heavy metal levels should be monitored strictly by the Gaborone City Council in order to prevent environmental pollution and reduce health hazards caused by pollutants.
Transgenic Plants as Sensors of Environmental Pollution Genotoxicity  [PDF]
Igor Kovalchuk,Olga Kovalchuk
Sensors , 2008, DOI: 10.3390/s8031539
Abstract: Rapid technological development is inevitably associated with manyenvironmental problems which primarily include pollution of soil, water and air. In manycases, the presence of contamination is difficult to assess. It is even more difficult toevaluate its potential danger to the environment and humans. Despite the existence ofseveral whole organism-based and cell-based models of sensing pollution and evaluationof toxicity and mutagenicity, there is no ideal system that allows one to make a quick andcheap assessment. In this respect, transgenic organisms that can be intentionally altered tobe more sensitive to particular pollutants are especially promising. Transgenic plantsrepresent an ideal system, since they can be grown at the site of pollution or potentiallydangerous sites. Plants are ethically more acceptable and esthetically more appealing thananimals as sensors of environmental pollution. In this review, we will discuss varioustransgenic plant-based models that have been successfully used for biomonitoringgenotoxic pollutants. We will also discuss the benefits and potential drawbacks of thesesystems and describe some novel ideas for the future generation of efficient transgenicphytosensors.
Transgenic Plants as Sensors of Environmental Pollution Genotoxicity
Igor Kovalchuk,Olga Kovalchuk
Sensors , 2008,
Abstract: Rapid technological development is inevitably associated with manyenvironmental problems which primarily include pollution of soil, water and air. In manycases, the presence of contamination is difficult to assess. It is even more difficult toevaluate its potential danger to the environment and humans. Despite the existence ofseveral whole organism-based and cell-based models of sensing pollution and evaluationof toxicity and mutagenicity, there is no ideal system that allows one to make a quick andcheap assessment. In this respect, transgenic organisms that can be intentionally altered tobe more sensitive to particular pollutants are especially promising. Transgenic plantsrepresent an ideal system, since they can be grown at the site of pollution or potentiallydangerous sites. Plants are ethically more acceptable and esthetically more appealing thananimals as sensors of environmental pollution. In this review, we will discuss varioustransgenic plant-based models that have been successfully used for biomonitoringgenotoxic pollutants. We will also discuss the benefits and potential drawbacks of thesesystems and describe some novel ideas for the future generation of efficient transgenicphytosensors.
ALTERNATIVE MICROBIAL INDICATORS OF FAECAL POLLUTION: CURRENT PERSPECTIVE  [PDF]
V. K. Tyagi, A. K. Chopra, A. A. Kazmi, Arvind Kumar
Iranian Journal of Environmental Health Science & Engineering , 2006,
Abstract: Worldwide coliform bacteria are used as indicators of fecal contamination and hence, the possible presence of disease causing organisms. Therefore, it is important to understand the potential and limitations of these indicator organisms before realistically implementing guidelines and regulations to safeguard our water resources and public health. This review addresses the limitations of current faecal indicator microorganisms and proposed significant alternative microbial indicators of water and wastewater quality. The relevant literature brings out four such significant microbial water pollution indicators and the study of these indicators will reveal the total spectrum of water borne pathogens. As E.coli and enterococci indicates the presence of bacterial pathogens, Coliphages indicate the presence of enteric viruses, and Clostridium perfringens, an obligate anaerobe, indicates presence of parasitic protozoan and enteric viruses. Therefore, monitoring a suite of indicator organisms in reclaimed effluent is more likely to be predictive of the presence of certain pathogens in order to protect public health, as no single indicator is most highly predictive of membership in the presence or absence category for pathogens.
Pollution in P2P Live Video Streaming  [PDF]
Prithula Dhungel,Xiaojun Hei,Keith W. Ross,Nitesh Saxena
International Journal of Computer Networks & Communications , 2009,
Abstract: P2P mesh-pull live video streaming applications – such as CoolStreaming, PPLive, and PPStream– have become popular in the recent years. In this paper, we examine the stream pollution attack,for which the attacker mixes polluted chunks into the P2P distribution, degrading the quality of therendered media at the receivers. Polluted chunks received by an unsuspecting peer not only effectthat single peer, but since the peer also forwards chunks to other peers, and those peers in turnforward chunks to more peers, the polluted content can potentially spread through much of the P2Pnetwork. The contribution of this paper is twofold. First, by way of experimenting and measuring apopular P2P live video streaming system, we demonstrate that the pollution attack can be devastating.Second, we evaluate the applicability of four possible defenses to the pollution attack: blacklisting,traffic encryption, hash verification, and chunk signing. Among these, we conclude that the chunksigning solutions are most suitable.
Concentrations of heavy metals in hair as indicators of environmental pollution
Baran A.,Wieczorek J.
E3S Web of Conferences , 2013, DOI: 10.1051/e3sconf/20130121005
Abstract: Over 80 hair samples were collected from 38% males and 62% females in Krakow, Poland. The hairs sampled for the analysis were washed in the water-acetone-water arrangement (three times). Subsequently the hair samples were wet mineralized in a closed system HNO3:H2O2 (6:1) in a microwave furnace. Concentrations of Zn, Pb and Cd were assessed by means of ICP-OES method. Obtained results of analysis of heavy metal concentrations in the hair of tested population of Krakow inhabitants evidence environmental hazard (beside professional hazard)We observed that the hair of females showed higher levels of zinc and cadmium. Hair analysis allows for an assessment of the natural environment contamination, which is particularly important for the research on populations inhabiting areas with different degree of pollution.
STUDY OF THE BACTERIOLOGICAL INDICATORS OF POLLUTION IN THE BASIN OF THE CIRIC RIVER  [cached]
Siimona Dunca,Marius Stefan,Anca Huma,Alina Gangiu
Analele ?tiin?ifice Ale Universit??ii Alexandru Ioan Cuza din Ia?i,Sectiunea II A : Genetica si Biologie Moleculara , 2007,
Abstract: To the purpose of assessing the level of bacteriological polllution of the water in the basin of the Ciric river, the study had the following objectives: determination of the probable number of fecal coliforms, fecal streptococci, sulphitereducing clostridia, and identification of the bacteria belonging to the Pseudomonas aeruginosa species and Salmonella genus. The results of the research studies showed fluctuations in terms of number in the hygienic-sanitary groups in all the points examined, even from one harvest period to the other (July and September 2006). The PNFS index exhibited low or even undetectable values in almost all the sampling points examined, while the PNFC/PNFS ratio higher than 4 in most of the points indicated the presence of a human source of water pollution. The water of the Ciric river, in most of the sampling areas and for both sample collection periods, was classified into quality classes III and IV both in terms of total coliforms and fecal coliforms.
Enzymatic and histopathologic biomarkers as indicators of aquatic pollution in fishes  [PDF]
Alaa G. M. Osman, Abd-El –Baset M. Abd El Reheem, Khalid Y. AbuelFadl, Ali G. GadEl- Rab
Natural Science (NS) , 2010, DOI: 10.4236/ns.2010.211158
Abstract: In the present study we investigated the alteration in the activity of two metabolic enzymes [Glucose-6-Phosphate Dehydrogenase (G6PDH) and Lactate Dehydrogenase (LDH)] and the histological changes on liver and gills of the African catfish Clarias gariepinus collected from 6 sites along the river Nile, from its spring at Aswan to its estuary at Rosetta and Damietta branches. The results showed that the physical and chemical parameters of the water collected from Damietta and Rosetta branches were higher than those of the water collected from other sites. Remarkable alterations in the activity of the selected enzymes in the liver and muscles of the African catfish were detected. These alterations go in parallel with the elevation in the levels of chemical parameters detected in the water of Damietta and Rosetta branches as a result of pollution stress in these areas. The activity of G6PDH was significantly (p < 0.05) decreased from Aswan to Rosetta and Damietta recording the highest value at Rosetta followed by Damietta water. The activity of LDH showed a significant elevation (p < 0.05) in activity in the liver and muscles of fishes collected from Rosetta and Damietta branches comparing to other sites. These alterations in enzymatic activities were followed, in the present study, by the occurrence of histological lesions and clear damage in liver and gill tissues of the African catfish collected from the same sites. Thus we may conclude that, the altered activities of G6PDH and LDH could be useful biomarkers of water pollution. At the same time, histopathology provides a reliable, easily quantifiable index of low-level toxic stress to a broad range of environmental pollutants.
Enzymes of Earthworm as Indicators of Pesticide Pollution in Soil  [PDF]
Rishikesh K. Tiwari, Shikha Singh, Ravi S. Pandey, Bechan Sharma
Advances in Enzyme Research (AER) , 2016, DOI: 10.4236/aer.2016.44011
Abstract: The importance of the earthworms in the agricultural practices is well known. The increasing applications of pesticides and chemicals in the agricultural farms have adversely influenced the flora and fauna of the soil. Earthworms which immensely contribute in increasing the quality and fertility of agricultural soil are reported be worst hit organisms under such conditions. Recent reports have indicated growing interests among researchers to explore biochemical and molecular markers as indicators of accumulation of pollutants in the soil in general and pesticides in particular. The varying levels of several biomolecules in different parts of the earthworm have been reported which are indicative of sensitivity of the organisms to different xenobiotics. However, the existing information lacks the literature displaying stock of information regarding the impact of pesticides on the levels of some key enzymes regulating many crucial functions in the earthworm at one place. Keeping in view this issue, it was envisaged to bring out a mini review which illustrates updated information available on the impact of pesticides on the activities of certain key enzymes reported to be responsible for catalysing metabolic pathways concerning the neurotransmission system, energy metabolism, oxidative stress and amino acids metabolism in different body parts of the earthworms, a prospective bioindicators of pesticides contamination in the soil.
Air pollution in a tropical city: the relationship between wind direction and lichen bio-indicators in San José, Costa Rica
Neurohr Bustamante,Erich; Monge-Nájera,Julián; González Lutz,María Isabel;
Revista de Biología Tropical , 2011,
Abstract: lichens are good bio-indicators of air pollution, but in most tropical countries there are few studies on the subject; however, in the city of san josé, costa rica, the relationship between air pollution and lichens has been studied for decades. in this article we evaluate the hypothesis that air pollution is lower where the wind enters the urban area (northeast) and higher where it exits san josé (southwest). we identified the urban parks with a minimum area of approximately 5 000m2 and randomly selected a sample of 40 parks located along the passage of wind through the city. to measure lichen coverage, we applied a previously validated 10 x 20cm template with 50 random points to five trees per park (1.5m above ground, to the side with most lichens). our results (years 2008 and 2009) fully agree with the generally accepted view that lichens reflect air pollution carried by circulating air masses. the practical implication is that the air enters the city relatively clean by the semi-rural and economically middle class area of coronado, and leaves through the developed neighborhoods of escazú and santa ana with a significant amount of pollutants. in the dry season, the live lichen coverage of this tropical city was lower than in the may to december rainy season, a pattern that contrasts with temperate habitats; but regardless of the season, pollution follows the pattern of wind movement through the city. rev.biol. trop. 59 (2): 899-905. epub 2011 june 01.
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