Biofilm Growth in Drinking Water Systems under Stagnant Conditions

Autor: Tsagkari, E., Sloan, W.T.
Přispěvatelé: Theodossiou, N., Christodoulatos, C., Koutsospyros, A., Karpouzos, D., Mallios, Z.
Jazyk: angličtina
Rok vydání: 2018
Popis: Safe drinking water is essential for human health and its provision in a changing climate is a global\ud pressing problem. Research communities, governments and drinking water supplying companies are\ud working on improving the quality of drinking water and reducing its cost. Microorganisms colonise\ud the inner surfaces of pipes and form biofilms. In drinking water systems biofilms are problematic as\ud they cause loss of disinfectants, harbour pathogens and affect the aesthetics of drinking water. From\ud the engineering perspective, that leads to corrosion of the pipe’s material and reduced life of the\ud existing infrastructure. Thus, it is imperative that we gain a deeper understanding of the growth of\ud biofilms if we are to develop effective strategies for their removal or control.\ud In this study we focused on the growth of biofilms in drinking water under stagnant conditions, which\ud often occur in parts of drinking water pipes. A bioreactor was used to simulate the service lines of\ud drinking water systems. After 4 weeks, the thickness and density of the biofilms were characterised\ud using gravimetric measurements, and their surface area was determined using fluorescence\ud microscopy. Also, the concentration of cells and microcolonies both in the bulk water and on the\ud reactor surfaces was determined using fluorescence microscopy. Finally, spatial statistics were used\ud to describe the biofilm structures that were formed on the exposed surfaces of the reactor. It was\ud revealed that even under stagnant and oligotrophic conditions, drinking water bacteria moved from\ud the bulk water of the reactor and attached to the available surfaces forming a high number of\ud microcolonies. Biofilms were able to grow on the exposed surfaces of the reactor forming\ud characteristic structures consisting of dense cell clusters. Our results revealed that even under\ud unfavourable conditions biofilms can grow within our drinking water systems.
Databáze: OpenAIRE