Water-Transmitted Fungi Are Involved in Degradation of Concrete Drinking Water Storage Tanks

Abstract

Global warming, globalization, industrialization, and the rapidly growing population at present increasingly affect the production of safe drinking water. In combination with sustainable bio-based or recycled materials, used for water distribution systems, these factors promote emerging pathogens, including fungi. They can proliferate in oligotrophic water systems, affect the disinfection process, degrade building materials, and cause diseases in humans. In this study, we explored fungal-based degradation of modern concrete water storage tanks and the presence of fungi in chlorinated drinking water at the entrance and exit of the tanks. The degradation potential of isolated 52 fungal strains and their growth at different oligotrophic conditions was tested in vitro. Forty percent of strains grew at extremely oligotrophic conditions, and 50% classified as aerophilic. Two-thirds of tested strains produced acids, with Penicillium strains as the best producers. Only 29.7% of the strains were able to grow at 37 °C, and none of them was isolated from drinking water at consumers’ taps. Although not yet part of the guidelines for building materials in contact with drinking water, fungi should be taken into consideration in case of visible degradation. Their number of consumers’ endpoints should be checked to exclude possible health risks for consumers.

Identifying eukaryotes in drinking water metagenomes and factors influencing their biogeography

“…While the higher presence/abundance detected for some modules in disinfected systems might be due to the generically higher Nonpareil coverage of samples derived from such systems, noticeably module 8 shows lower presences in disinfected systems indicating potentially the higher sensitivity of its members to disinfection or the adaptation to low nutrient conditions of non-disinfected DWDSs. In fact, some nodes included in module 8 represent fungi for which some species are known to proliferate under oligotrophic conditions 115 and demonstrate higher chlorine resistance than viruses and prokaryotes, but lower than protists cyst and oocysts 96,116 . Furthermore, climate zone D (i.e., continental) showed in most cases differences in the presence/abundance of the modules’ members compared to zone A (i.e., tropical), in accordance with the expected climatic differences and geographical distances among the two zones 74 .…”

“…In fact, some nodes included in module 8 represent fungi for which some species are known to proliferate under oligotrophic conditions 115 and demonstrate higher chlorine resistance than viruses and prokaryotes, but lower than protists cyst and oocysts 96,116 . Furthermore, climate zone D (i.e., continental) showed in most cases differences in the presence/abundance of the modules' members compared to zone A (i.e., tropical), in accordance with the expected climatic differences and geographical distances among the two zones 74 .…”

Soil Microbial Community Composition and Tolerance to Contaminants in an Urban Brownfield Site

“…This group of fungi can degrade PAH in vitro [ 26 ]. On the contrary, much less is known about the fungal genus Furcasterigmium ; it is a fungal group commonly found in drinking water storage tanks and within wet walls [ 101 ]. Stachybotrys are filamentous fungi common in soil, decaying plant material, and submerged wood in mangroves [ 102 ].…”

Identifying Eukaryotes and Factors Influencing Their Biogeography in Drinking Water Metagenomes

“…While the higher detections for some modules and module members in disinfected systems might be due to the generically higher Nonpareil coverage of samples derived from such systems, noticeably, module 8 shows lower detection in disinfected systems, indicating potentially the higher sensitivity of its members to disinfection or the adaptation to low-nutrient conditions of nondisinfected DWDSs. In fact, some nodes included in module 8 represent fungi for which some species are known to proliferate under oligotrophic conditions 122 and demonstrate higher chlorine resistance than viruses and prokaryotes but lower than protists cysts and oocysts. 101,123 In accordance with the expected climatic differences and geographical distances among the two zones, 78 climate zone D (i.e., continental) showed, in most cases, differences in the detection of the module members compared to zone A (i.e., tropical).…”