Water is vital for all life on Earth, with humans alone being made of up to 60% water. However, even though about 70% of the Earth’s surface is water; with 97% of that being taken up by oceans, and a further 1.6% being frozen in glaciers, that leaves only 1.4% of the water on Earth being accessible fresh water. So we must keep this water clean and free of pollution.

However, this has become increasingly difficult with the rise of industry and the booming population of humans and farm animals. Industries such as mining, refining, heavy metals, leather, food, chemicals, pharmaceuticals, dyes, pesticides, detergents, and many more are increasingly polluting the world’s drinking water. According to the World Health Organization, over 30% of all human illnesses and 40% of all deaths worldwide are caused by polluted water. Therefore, we must remove all pollutants from the water before they reach our waterways.

Bioremediation – a process where microorganisms degrade or transform contaminants to make them less toxic or even non-toxic – is toted as a sustainable and cost-effective method to treat wastewater and remedy environmental contamination. Currently, the process is dominated by bacteria; however, new studies have shown the potential of using fungi instead.

Which fungi work best for wastewater bioremediation?

Most fungi grow in one of two different ways. The first, filamentous fungi, grow as polarized branching mycelium. The second, yeast fungi, grow as rounded or spherical cells. Whereas you might assume that fungi must use one system or the other, in fact, they often grow in either form depending on the environment they are cultivated in.

For bioremediation, the most useful fungi grow as filamentous fungi. They have a large area, a high level of mass and oxygen transfer, and even grow in a net-like structure. They are simple to grow, non-toxic, and risk-free while having an increased level of adsorption. In addition to this, they grow and reproduce rapidly and adapt well to a variety of pollutants, and filamentous fungi outperform bacterial remediation in a massive way. 

Both living and nonliving fungi can absorb water to remove toxins; however, currently, there is a preference for dead fungi due to them not requiring any other nutrients to stay alive, as well as being able to be stored for longer. They can also absorb heavy metals and dyes, often present in wastewater, and pose a large threat if not treated. They can severely impact aquatic life, such as fish and underwater plants, and there is currently no way to remove these substances without a high cost and long implementation time.

Fungi’s ability to degrade pollutants

But fungi don’t only capture pollutants in the water; they can also degrade them. Fungi can dissolve many organic materials – some of which are toxic – into a non-toxic form. Not only that, but some of these forms can then be reused as commodities!

It isn’t only human pollutants that fungi can help harvest from water. Many uses for a substance called microalgae have been discovered in the medical profession, the food and animal industry, wastewater treatment, environmental engineering, renewable energy, and many more. However, the current process for harvesting this microalgae faces significant challenges that can also be solved by using fungi.

This all sounds too good to be true. In fact, many steps need to be taken before fungi can be used effectively in wastewater management.

Challenges in Using Fungi for Wastewater Treatment

To begin, there are only a small number of fungi species that can be used for such treatment. Much research still needs to be done to identify other species and meet an increasing demand. This demand is a second issue – many of the fungal species suitable for wastewater management have a wide variety of uses and, therefore, are in high demand. However, production costs for these pellets remain high, which reduces the amount of supply to meet the demand.

Much more research is needed into how fungal biomass can be used to treat wastewater, as current studies focus mainly on bacteria, algae, or even manmade solutions. Research will also be needed to determine the best ways to implement fungi-based solutions without just trying to fit fungi into the current solutions.

To find out other ways fungi are being used to clean up pollution, check out these articles: Mushroom Substrate Waste Proves Efficient at Breaking Down Water Pollutants and Mycoremediation: Cleaning Up with Fungi That Eat Plastic – Shroomer