Current Issue : October - December Volume : 2016 Issue Number : 4 Articles : 6 Articles
Ecological impacts of contaminants on population patterns in wild fish are impacted by many contaminants\nthat readily enter aquatic systems. Responses to toxicants by individuals in lab studies\ngenerally do not predict population level consequences in natural systems. Trace levels of contaminants\nare present in all major rivers in southern Alberta, Canada, with concentrations higher downstream\nof anthropogenic inputs like agricultural land-use and inputs of municipal wastewater effluents.\nLongnose dace (Rhinichthys cataractae) were used as a sentinel species to study field-based\npopulation-level responses to contaminants. We hypothesized that biomarker activity, triggered by\ncontaminant exposure, should increase downstream of anthropogenic inputs in two southern Alberta\nrivers, with corresponding relations between biomarker activity and sex ratios, after accounting\nfor age structure. Liver detoxification (ethoxyresorufin-O-deethylase activity = EROD) measured\nat reference and exposed sites on each river differed significantly in only the Bow River system. Sex\nratios varied more downstream of anthropogenic inputs than upstream, but the direction of sex ratio\nbias was inconsistent and temporally dynamic. Sex ratios correlated with liver detoxification in\nonly the Bow River. Taken together, these results suggest that contaminants alter sex ratios in longnose\ndace, but that there is variation in anthropogenic stressors among rivers....
Industrial effluents containing cobalt ions have become a serious problem for the environment,\nunless properly treated, due to their toxic potential. Currently there has been an intensification of\nthe use of cobalt in several industrial sectors as super alloys, catalysts, batteries and pigments in\nceramic materials, and a consequent intensification also of environmental contamination. This\npaper aims to show a simple and effective treatment for the removal of cobalt ions from simulated\nindustrial wastewater, based on cathodic eletrolytic removal using a carbon steel screen. As a result,\na 73% removal of cobalt ions from solutions was achieved with a concentration of 400 mg\nCo2+/L, a current of 0.30 A and a voltage of 30 V. In the same conditions, 84% and 88% was removed\nfrom 200 mg Co2+/L and 100 mg Co2+/L, respectively. Thus, this method presents itself as a\ncheap and efficient alternative for the treatment of industrial effluents containing cobalt ions....
In this study research on the heavy metals concentrations in ground water samples of the Karur, Tiruchirappalli and Thanjavur districts of Tamil Nadu, India during April 2015 was done. Heavy metals were analyzed by using standard methods. Heavy metal concentration in ground water was in following order Fe > Zn > Cr > Cu > As > Hg > Pb > Cd (ppm). The high level of heavy metal (Iron) was recorded from Kundur ground water samples and low level of heavy metal (Lead) was recorded in Kundur and Mathur areas of ground water samples....
This work refers to the characterization of the hydrochemistry of the southern part of the Eastern\nDesert in Egypt, on the basis of physico-chemical properties of groundwater occurring in the fractured\nPrecambrian rocks inland and in sedimentary formations on the coastline of the Red Sea.\nThirty-five groundwater samples have been collected from the study area for hydrochemical investigations\nto understand the sources of dissolved ions and assess the chemical quality of the\ngroundwater. Several methods were used to interpret the hydrochemical data, i.e. graphical methods,\nprincipal components analysis, ions exchanges indices and saturation indices of various\nminerals. The results show that the major ionic relationships are Na+ > Ca2+ > Mg2+ and Cl > 2\n4 SO >\nHCO3 and that groundwater chemical characteristics are controlled by natural geochemical\nprocesses but also, to a lesser extent, by anthropogenic activities. Natural minerals dissolution, ion\nexchanges and evaporation play a prominent role in the ion enrichment of groundwater. A comparison\nof groundwater quality in relation to WHO water quality standards proved that most of\nthe water samples are not totally suitable for drinking water purpose....
Although drinking water is readily available in Benin, its quality presents a public health concern.\nThe district of AhomadÃ?©gbÃ?© in the commune of Lalo is characterized by several artesian wells. Unfortunately,\nanthropogenic factors negatively affect the drinking water quality in this area. The\naim of this research was to study the microbiological quality of drinking water in the AhomadÃ?©gbÃ?©\ndistrict, and to review household water treatment methods employed by the local population.\nThirty-five water samples were takenââ?¬â?at water collection points, at selected points along the water\ntransportation system and from water storage facilities, and microbiological parameters were\nmeasured. Qualitative data were collected via in-depth interviews with key informants regarding\nlocal household water treatment methods. Results reveal that there is a significant degree of\nmicrobiological pollution of drinking water in this district, particularly during the water transportation\nand storage stages where microbiological pollution exceeds levels approved by the\nWorld Health Organization. Local residents are familiar with several household water treatment\nmethods. However, these methods are inconsistently applied, which limits their effectiveness. In\naddition to improving the quality of the drinking water resource itself, it is important to set up interventions\nrelating to water treatment methods in local households....
Three tributaries of the Grand River watershed (Ontario, Canada), each representing different\nwatershed types (urban, agricultural/rural, and mixed land-use) were examined to understand\nthe spatial, temporal, and host-source distribution of the waterborne pathogen, Cryptosporidium.\nCryptosporidium was frequently found throughout the study (73%, 65/89) with occurrence and\nconcentrations observed to be similar among the varying watershed types. However, applying advanced\ngenotyping techniques, marked differences in dominant host sources could be observed in\neach watershed. The agricultural/rural and mixed land-use watersheds were dominated by genotypes\ntypically associated with cattle (i.e., C. andersoni), while the urban watershed had the highest\ndiversity of Cryptosporidium genotypes with a variety of wildlife as the common source of contamination\n(e.g., muskrat and cervine genotypes). A similar seasonal trend observed in the urban,\nagricultural, and mixed land-use watershed suggests that factors beyond specific land use activities\n(e.g. autumn manure spreading) may influence the timing and concentration of Cryptosporidium\nin these streams. Corresponding genotyping results provided additional insight into source\ninputs during these seasonal peaks, indicating that wildlife may be important seasonal contributors\nto Cryptosporidium contamination in these streams. Despite the abundance of Cryptosporidium\nin these watersheds, most of the genotypes observed were of limited human health importance.\nThis study provides evidence regarding the significance of including genotyping results into\nstudies examining waterborne Cryptosporidium. Using this technique can provide a greater un-derstanding of the risk to the population using water sources, as well as provide insight into the\nprobable sources and timing of contamination. This ancillary information can contribute to implementation\nof targeted management strategies to further protect sources of drinking water and\nrecreation areas....
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