A significant proportion of water for human consumption has an underground origin becoming 80% in Chilean rural areas where profound wells represent the only search of water for human and animal ...beverage.
To study the microbiological quality of water from agricultural land for livestock production in the province of Valdivia (40°S), Chile and its potential impact on human health.
Water samples were collected monthly (2008 - 2009), at the entrance and exit of a water stream running through the field and in well water used for human and animal consumption. The total coliform (Tc) and Escherichia coli were determined by the confirmatory method Quanti-Tray together with other physicochemical assessments in the water and climatic variables.
In samples from the stream water and wells, the Most Probable Number of Tc and E. coli exceeded the standard Chilean Norm of Water Quality (NCh 409/1) for human consumption.
These results show the need to regulate the environmental impact of farming and cattle production and to monitor the drinking water to meet the minimum standards of health protection.
Manyas, also known as the Bird Paradise Lake, is situated near the south-eastern coasts of the Marmara Sea in Turkey. This shallow lake, is a unique natural reserve providing habitat for migratory ...birds with its rich fauna and plankton species. The objective of this work is to study the ecological and water quality changes resulting from increasing anthropogenic pollution and human intervention on the natural variations of the water level. For this purpose, physical, chemical and microbiological aspects of the aquatic ecosystem in the lake of Manyas are being measured semimonthly since more than a year. After the completion of field measurements associations between different parameters will be searched by means of a water quality model. Results obtained will be used in the sustainable restoration of the lake. In this paper, firstly the nutrient and trophic dynamics of the planktonic ecosystem are associated with the bio-geochemical water cycle in the lake. Secondly, space and time distributions of all physical, chemical and microbiological data are presented and interactions between the nutrient availability and some microscopic communities are discussed.PUBLICATION ABSTRACT
In this work the resistance of 172 motile
Aeromonas isolates recovered from raw drinking water supplies (56), irrigation waters (60) and runoff waters receiving sewage (56), to some antibiotics and ...heavy metals was investigated by agar diffusion and agar dilution methods. A high proportion of isolates from all water sources showed resistance to carbenicillin, erythromycin, streptomycin, cephradine and cadmium, and susceptibility to chloramphenicol, kanamycin, gentamicin, tetracycline, nalidixic acid, trimethoprim–sulphametoxazole and chromium. No amikacin-resistant
Aeromonas were recovered. No relationship was found between antimicrobial resistance and
Aeromonas species, with the exception of cephradine, that exhibited a significantly higher activity against the
A. sobria isolates than the other
Aeromonas species (
P<0.05). Moderately polluted waters showed lower antibiotic multiresistance and metal susceptibility than unpolluted and highly polluted ones. Although significant differences (
P<0.05), between resistance frequencies to erythromycin, carbenicillin, streptomycin and cephradine were found among isolates from different sources, the antimicrobial resistance patterns of aeromonads could not be related to the level of faecal pollution. These results indicate that aeromonads resistant to antibiotics and heavy metals are easily recovered from water sources in Chile, posing a potential public health risk.
Results showed that surface resource water quality in the study catchment was generally of a poor health-related microbiological water quality. This was due to poor quality discharges received from ...urban developments in the catchment. The quality results implied that several water uses in the catchment would impact negatively on the health of the users. Current developments in setting Resource Quality Objectives to manage the quality of the resources involved do not provide for the various water uses. The particular Catchment Management Agencies would, therefore, not be in a position to judge the health-related status of their surface water resource quality objectively. To alleviate this problem, tentative water-use classifications as well as microbiological criteria are proposed.
Abstract
The presence of Salmonella and its relationship with indicators of faecal pollution was investigated in aquatic habitats. The highest frequency was obtained in rivers (58.7% of samples) ...followed by freshwater reservoirs (14.8%) and sea water (5.9%). The sporadic presence of Salmonella (<30%) on beaches with low concentrations of faecal streptococci (mean 25 CFU (100 ml)−1) may represent a potential risk for bathers in agreement with data found in previous epidemiological studies. Absence of Salmonella was observed only on beaches with very low densities (CFU (100 ml)−1) of indicator organisms (25 total coliforms, 13 faecal coliforms and 17 faecal streptococci).
This chapter covers the microbiological quality of source waters as well as the microbiological aspects of water treatment processes. Due to the scarcity of quality source water, communities must use ...reclaimed water. Communities obtain their potable water mostly from surface or underground sources. Both types of water can become contaminated by biological and chemical pollutants originating from point and nonpoint sources. There are two main categories of water treatment plants: conventional filter plants and softening plants. In water treatment plants, microbial pathogens and parasites can be physically removed by processes such as coagulation, precipitation, filtration, and adsorption, or they can be inactivated by disinfection or by the high pH resulting from water softening. Nanomaterials are also promising for the removal of chemical pollutants from drinking water. Most of the nanotechnology‐based treatments have been tested under laboratory conditions and more research is needed to evaluate their performance under field conditions.
Much attention is given to the recording of diarrhoea incidence among children under the age of 5. This is used as an indicator of health of the community since diarrhoea historically has a more ...profound effect on children and elderly people. Diarrhoea incidence for children under the age of five is noted at each health facility and is available on a national database. Almost no attention has been given to adult diarrhoea. Trend lines however suggest an increase in the number of deaths in adults due to diarrhoea. This suggests an increase in the number of adults suffering from this illness. From the above it is clear that adult diarrhoea in SA should be a concern. The question is therefore – are we still measuring the correct things? More attention should be given to the incidence of diarrhoea amongst people in the adult population. In addition, the provision of safe in-house water supply or access to private water supplies is becoming critical.
15th International Symposium on Health-Related Water Microbiology, Naxos island, Greece, 31 May – 5 June 2009
Rapid urban growth in metropolitan Cape Town is subjecting the inland and coastal waters in the region to stress. Increasing extractive demands are being made on inland water systems to provide ...potable water. Larger volumes of liquid and solid waste, and increased stormwater runoff, are influencing negatively the nutrient and microbiological quality of inland and coastal water systems. Urban sprawl and informal housing are detracting from the aesthetics of river catchments, and are also detrimental to river and stormwater quality. These stresses have particularly serious implications for Cape Town because the future economic growth of the area is dependent on a high-quality environment. Constraints to the sustainable management of water resources are discussed under the broad themes of institutions, law and regulation, finance and economics, and lack of information, public awareness, holism, and realism.
Water samples of different pollution levels were collected from four different sources, viz., a canal, an open dug well, a deep tube well, and a drinking water tap, stored at refrigerator (4-5 ...degrees C) and ambient (28-30 degrees C) temperatures, and analysed at 0, 6, 12, 24 and 48 hours in order to find the effect of holding time and temperature on bacterial counts. The samples were analysed for total coliforms and for heterotrophic plate counts (HPC). Results of the study indicate significant reduction in the coliform counts in all the water samples tested at both ambient and refrigerator temperatures. However, the rate of decline was much less in refrigerated samples compared to that in samples stored at ambient temperature. Further, the rate of decline was dependent on the source of water. After 48 hours of storage at ambient temperature, canal water samples showed the sharpest decline of 82% in coliform counts, and water samples from open dug well showed the least decline of 51%. While HPCs of the samples held at refrigerator temperature did not show significant changes with time, those samples held at ambient temperature increased upon storage. Up to 12 hours of storage, there was no significant changes in bacterial counts in any type of water at both the temperatures, which suggests that water samples can be stored at ambient temperatures for 12 hours without significantly affecting the coliform counts.
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