Published in Scientific Papers. Series "Journal of Young Scientist", Vol. 10
Written by Estera BIVOLARU, Marcela CHIRU, Daniela VĂCĂROAIA, Denis NENCIU
Mismanagement of drinking water supplies can pose serious public health risks. There are many concerns about water source management among private well owners, as they are often solely responsible for maintaining their wells, and monitoring and testing of their own water quality. Lack of worry about contamination and a strong sense of control over risks in relation to drinking water quality have been identified as important factors that influence peoples' perceptions and behaviour. The most effective way to check water supplies for faecal contamination is microbiological analysis, and a range of test methods designed for that purpose has been developed for the water analysis. Instead of carrying out separate tests for each of the potential pathogens, viruses, or parasites that might be in the water, microbiologists test for indicator organisms that are always present when enteric pathogens and viruses are. Defined substrate technology (DST) developed by IDEXX can produce results in 24 hours. The IDEXX Colilert uses a colourimetric ONPG assay to detect coliforms and a fluorescence MUG assay for E. coli. Colilert can simultaneously detect these bacteria within 18-24 hours. It can also suppress 2 million heterotrophic bacteria per 100 mL present. As of 2014, this technology from IDEXX has been published as a European Standard Method, and many countries now use this technology as their gold standard for water testing like Finland and Ireland. The Enterolert Test from IDEXX uses a proprietary Defined Substrate Technology (DST) nutrient indicator to detect enterococci. This nutrient indicator fluoresces when metabolized by enterococci. DST improves accuracy and avoids the need for hazardous sodium azide suppressants used in traditional media. In order to achieve the proposed goal, the groundwater sample taken from a family from Tamasi, Corbeanca commune, Ilfov county was analyzed in the laboratory of Ecology and Environmental Microbiology, F.I.F.I.M., U.S.A.M.V. Bucharest from an organoleptic, physicochemical and microbiological point of view. The groundwater sample from a private well was taken from the kitchen cold tap water of a family in a sterile glass container for organoleptic, physicochemical and microbiological analyses. The underground water from the private well comes from a depth of 120 m and the drilling is located in Tamasi, Corbeanca commune, Ilfov county. The groundwater sample was transported in a refrigerated box to the laboratory of Ecology and Environmental Microbiology within the Faculty of Land Reclamation and Environmental Engineering within the U.S.A.M.V. Bucharest. The experiments performed and presented in this paper represent a part of the studies performed for the bachelor's thesis. All analyzes for water quality (colour, taste, smell, pH, turbidity, ammonia, nitrites and nitrates) from the private well fall within the maximum limits allowed by the standards in our country, except for the concentration of water hardness that exceeded the limits allowed. Microbiological analyzes for the detection of faecal contamination of the water sample using classic methods and IDEXX defined substrate technology confirmed the absence of coliform indicator bacteria. The recommendation for bringing the water hardness to optimal parameters and falling within the water quality standards was to install a water softening station.
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