Drinking water reservoirs are widely used in various building constructions inBrazil for as a source of potable water for users. However, they are susceptible tothe growth of microorganisms such as fungi. From these, several negative factorsmay ensue, namely, unpleasant odors and flavours, pigments, biofilm formationand mycotoxins. This is caused fungal resistance to treatment and disinfection.Brazilian law and those of other countries offer no encouragement for the researchof the species of fungi that cause these problems. There are no legal limits as tothe presence in drinking water. This study assesses the occurrence of filamentousfungi in drinking water reservoirs connected to the Alto do Céu distribution systemlocated in Recife, Pernambuco, Brazil. Four monthly collections were carried out,in triplicate, at two fixed points in the network, at the same treatment area, andanother 2.0 km away from this site. For water physicochemical characterization atthe time of collection, pH, temperature and free residual chlorine were analyzed.Filamentous fungi were quantified by filtration through cellulose nitrate membranewith a 0.45 μm porosity. All strains were grown in Petri dishes containing PeptoneGlucose, Rose Bengal Agar (PGRBA) and were incubated at 30°C for 48h. Fungaloccurrence was quantified as colony forming units (CFU) per litre. Twenty-foursamples were analyzed, and these accounted for 807 CFU. Considering the potentialfor water spreading diseases, and the high toxicity of fungi into account it isintended that this work may prompt the creation of acceptable parameters as tothe presence of fungi in drinking water networks.
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