Fungi Are Capable of Mycoremediation of River Water Contaminated by E. coli

Wastewater pollution results in detrimental effects on ecosystems and poses human health hazards. As the human population and urbanization rates increase, so do abiotic and biotic contaminants such as Escherichia coli within natural waterways. For example, the Chicago River has been degraded by contaminants and untreated sewage from city occupants since the late 1700s. Surprisingly, water treatment of the Chicago River has not met EPA freshwater river standards for some time, creating a need for remediation alternatives. Such an alternative is mycoremediation, where fungi are used to degrade and remove water contaminants. To explore this alternative for bioremediation of contaminated waterways, this two-part study focused on the feasibility and time efficiency of mycoremediation of polluted waters through mycofiltration. In the lab-based experiment, known amounts of E. coli-inoculated water were processed through organic wheat straw with mycelia of Pleurotus ostreatus (oyster mushroom) to assess if these fungi were capable of E. coli removal and at what rates. The second part of the study replicated the lab-based experiment with water samples from the Chicago River. Results showed that mycelia treatments were able to remove significant amounts of E. coli in lab- and field-sampling-based settings (99.25% and 99.74% over 96 h respectively), and did so at higher rates within the initial 48 h. With a substantial E. coli reduction by fungal mycelia from initial colony counts over 96 h, our study demonstrated that mycoremediation may be a feasible and possible option for natural contaminant remediation.