PhD defence: Waste treating waste: Organic micropollutant removal from water by Agaricus bisporus spent mushroom substrate

Our society is facing a severe and pressing problem of increasingly polluted water which leads to health hazard. Currently, two billion people reside in water-stressed areas, and over 800 million lack adequate access to safe drinking water. Due to the rapidly decreasing water quality, also in European countries, these numbers will likely increase. The primary source of clean water is ground and surface water; however, it has been already proven that a half of the world’s rivers and lakes are currently polluted.

There are various pollution’s origins, such as:

• Inefficient and ineffective pesticide use in agriculture
• Pharmaceuticals and personal care products (PPCPs) which end up in the water streams and water sources via hospitals and households;
• Concentrations of industrial compounds, like textile dyes and commonly used per- and polyfluoroalkyl substances (PFAS).

Bioremediation is a sustainable and cost-effective solution for micropollutant removal when compared to other processes. With this research, we successfully demonstrated that more efficient alternative in bioremediation are wood and litter degrading fungi (WLDF): the fungi are able to remove from water a wide range of micropollutants such as pesticides, textile dyes, PPCPs and PFAS. An example of WLDF is the white button mushroom, with the worldwide production volume of 5 million ton per year. For commercial this mushroom grows on an organic substrate, which is about three times the mass of the produced mushrooms. This substrate is considered a waste stream after harvesting the mushrooms. However, we proved that such substrate is able to remove a mixture of micropollutants in water up to 75% in only two days. Moreover, PFAS components (GenX and PFOA) were effectively eliminated using WLDF substrates in bioremediation experiments. It is important to note that our research represents the first report of PFAS removal using WLDF substrate.

Concluded, this study opens the door to an eco-friendly approach to water purification using mushroom waste.