Bacteriophages for Sustainable Wastewater Treatment: A Promising Solution

Introduction

Amid a global climate crisis, environmental protection and improved sustainability are pivotal to protecting the planet and sustaining the health of its inhabitants. Human activities, including industrialisation, urbanisation, and agriculture, are having a devastating effect on the environment, leading to increased environmental pollution, including water pollution. With the growing global population, there is a rising demand for safe drinking water. As a result, wastewater must be treated to reduce the abundance of pollutants before it is released into the environment. Wastewater can then be led back into water bodies, re-extracted, and re-used for utilities.

Traditionally, wastewater treatment methods have involved filtration, flocculation, and chemical precipitation. These methods employ vast wastewater treatment plants, which are costly to build and run.  Wastewater plants take up vast amounts of land and have high energy consumption, leaving them with a large environmental footprint. Conventional treatment plants involve microbiological processes such as activated sludge, which can cause foaming; an operational and environmental risk. Finally, traditional wastewater treatment methods are not effective at removing all potentially harmful pathogenic contaminants. 

Recently, more sustainable methods for wastewater treatment have begun to emerge. One such method is the use of bacteriophages, commonly known as phages. Phages target and destroy specific bacteria strains and have shown promise in solving the challenges associated with traditional wastewater methods.

Bacteriophages and Sustainable Wastewater Treatment

Bacteriophages are naturally abundant viruses that selectively target, replicate within, and kill bacterial cells. They do this by attaching to a susceptible host and introducing their genome into the host cytoplasm, which allows them to replicate by lytic or lysogenic replication. Lytic phages are naturally successful bactericidal agents, meaning bacteria cannot sustain viability after infection. Phages are diverse in terms of morphology, genomic organisation, and host species and can be exploited to control microbial growth across a range of medical, agricultural, and environmental applications. 

Bacteriophages can be employed at numerous stages of the wastewater treatment process. In bioaugmentation, specific bacteriophages are added to water treatment plants to increase the degradation of pollutants and enhance the efficiency of the treatment process. Since phages naturally flourish in wastewater and are effective at eradicating biofilms, they are a potent, cost-effective, and environmentally friendly means of improving the efficiency of wastewater treatment compared to traditional physicochemical methods. Furthermore, the specificity of phages means they can be used as biosensors to indicate strains of bacteria present in wastewater, helping to recognise and control the spread of harmful pathogens. 

Phage therapy involves using bacteriophages to target and destroy specific bacteria in wastewater, including pathogens. The addition of a well-selected population of bacteriophages can ensure the successful removal of bacteria that proved resistant to traditional disinfectant methods. For example, a study isolated a phage from wastewater that showed lytic activity against multi-drug resistant E.Coli strains. Treating wastewater with phage has the potential to reduce activated sludge bulking and foaming, and allows previously contaminated wastewater to be recovered and reused for utilities, reducing resource waste and improving sustainability.

Protecting Our Waterways: How Bacteriophages Can Help Combat Water Pollution

In addition to their role in wastewater treatment, there is potential for bacteriophages to play a significant role in preventing the spread of waterborne pathogens in waterways. Waterborne pathogens can cause severe and sometimes fatal illnesses such as cholera, typhoid fever, and dysentery. Selectively targeting and killing harmful bacteria in waterways by bacteriophage treatment reduces these risks, improving public safety and health. In addition, bacteriophages can control bloom-forming cyanobacteria in freshwater bodies such as lakes, which represents an environmental hazard. Traditional methods to kill bacteria in waterways have involved chlorination, which is not always effective at eliminating all pathogens. It is also unselective, meaning it may also destroy beneficial bacteria. Harmless bacteria are naturally abundant in waterways and assist in water purification, ultimately improving water quality. 

Another positive environmental impact of utilising bacteriophages in wastewater treatment is their potential to reduce the ecological footprint of treatment plants by reducing both their energy consumption and curtailing their generation of greenhouse gases. Bacteriophages offer a more sustainable alternative as they can be isolated from natural, renewable resources, and do not require significant amounts of energy to produce. Additionally, phage therapy can prevent bacterial contamination at the source, reducing the need for costly and energy-intensive treatment methods downstream.

The use of bacteriophages in water treatment has potential implications for public health and environmental policy. Regarding public health, phage-based treatment can lead to cleaner and safer water, reducing the risk of waterborne illnesses. This positively impacts overall public health and reduces the burden on healthcare systems. From an environmental policy perspective, microbiological control represents more sustainable and environmentally-friendly water treatment processes, reducing the carbon footprint of wastewater treatment and preserving natural ecosystems.

The Future of Environmental Microbiology: Advancements in Bacteriophage-Based Treatments

Environmental microbiology is a rapidly evolving field encompassing the complex relationships between microorganisms and the environment, which can significantly impact ecosystems, human health, and industries such as agriculture, energy, and waste management. Bacteriophage-based treatments represent a promising area of innovation within microbial ecology; wastewater treatment, and beyond. 

Ongoing research efforts are exploring the potential of bacteriophage-based treatment applications, including wastewater treatment, food safety, agriculture, aquaculture, and in medical treatments. Recent advances, particularly in genomics and synthetic biology, have enabled scientists to design and engineer bacteriophages with specific properties, expanding the potential applications of bacteriophage-based treatments.

The potential applications of bacteriophage-based treatments represent significant market 

opportunities for biotech companies. The global market for more sustainable industrial solutions, and the need to combat problems such as the antibiotic resistance crisis, are expected to grow exponentially in coming years. Therefore, companies that can develop safe and effective bacteriophage-based treatments for these applications stand to benefit hugely.

Conclusion

With the current climate of a growing global population and an environmental crisis, traditional wastewater treatment methods are facing a growing number of challenges, and there is an urgent need for better, more sustainable solutions. The potential of bacteriophages in addressing the challenges facing traditional wastewater treatment methods is promising; bacteriophage-based bioremediation may improve treatment sustainability and water quality. Further research and development are necessary to understand the full potential of bacteriophages in water treatment. However, it is a promising approach with the potential to revolutionise environmental protection, sustainability, human health, and consideration for public health and environmental policymaking.