digest the rest

Each day, a large number of pharmaceuticals, their degradation products, and other micropollutants end up in our wastewater. The concentration of heavy metals, hormones, and antibiotics in the groundwater is therefore increasing strongly impacting our environment.
The toilet paper flushed has a mycelial component that is only reactivated during flushing. The hyphal network is able to metabolise pollutants dissolved in the water on its way through the sewage system. Four different methods and material experiments are used to show how living organisms can be integrated into industrial toilet paper production.


Sophia Reißenweber
project:mutual affairs

full concept text

Dyes, herbicides, heavy metals, hormones, antibiotics, diclofenac, and ibuprofen are examples of micropollutants in our wastewater. According to the Federal Environment Agency, 414 different pharmaceutical residues can be detected in the soil, rivers, and our drinking water in Germany alone.
As the concentration of these substances increases, this has a major impact on our environment. Among other things, this results in an increased antibiotic resistance.
Currently, however, sewage treatment plants can do little to prevent this. Bacteria and protozoa metabolise our excreta and contribute to the production of drinking water from wastewater, which is then added back to the natural water cycle or simply discharged back into the nearest river. In addition, conventional strategies for treating contaminated water are costly, energy-intensive, and often result in the production of toxic by-products.

Mycoremediation – the expansion of environmental pollutants through mycelium – can therefore be a cheap and effective alternative.
Because of their special enzymes, even the native species of white rot fungi, such as the popular oyster and herb mushrooms, are suitable for this.
But how can we properly integrate these living organisms into our everyday lives and consciously activate their properties?

Besides industrial drains and manhole covers in public spaces, most micropollutants in everyday use enter the wastewater via the toilet. This is where my toilet paper flushed comes in, which has a mycelium component that is only reactivated when flushed. The hyphal network is able to metabolise the pollutants dissolved in the water on its way through the sewage system. Fungi can even withstand the extreme conditions there and adapt to the fluctuations in the sewer system.

Using four possible strategies and material experiments, I investigated how mycelium can be integrated into industrial toilet paper production:

In the Growler method, the mycelium grows into shape in liquid culture. After 10 days, it is slightly dried and placed between 2 layers of cellulose, with which it eventually grows together. This is followed up by it being gently air dried, embossed, and perforated.

In addition, waste material from paper recycling can be mixed with small amounts of nutrients, which then serves as a substrate for the mycelium. In the pampler process, the hyphae bind the fibres together creating a stable composite material. By reusing short paper fibres, new value can be created in the cycle.

Another possibility is the freeze-drying of mycelium. The stackler roll therefore has a long shelf life and can easily be stored at home. The lyophilised mycelium can simply be applied as powder between the layers in the production process.

Thanks to the innovative and quite new electrospinning technology, it will soon be possible to apply a wafer-thin nanofibre layer of mycelium to toilet paper. This effective coating follows the spinnler principle.

flushed will initially be available in pharmacies. Depending on the medication, the appropriate mycelium roll is recommended and can even be prescribed by the doctor. The toilet paper is also used in hospitals and the homes of senior citizens allowing for a a large sales market.