The Journey of Phytoremediation: From Hype to Proven Technology

This essay is based on the insights of Paul Thomas, drawn from a recent conversation on the state of the field of phytoremediation.

Phytoremediation’s Perception

Phytoremediation emerged in practice, though not in name, in the 1980s. The term was coined in the early ‘90s as a part of a Rutgers professor’s grant application. However, like many groundbreaking ideas, it has experienced the ebb and flow of positive public perception. But what is the state of the field now and where are we going? A look at phytoremediation’s perception history through the lens of the Gartner hype cycle yields some insights. 

What is the Gartner Hype Cycle? 

The Gartner hype cycle is a conceptual framework that illustrates the typical trajectory of emerging technologies or concepts, depicting the various stages they undergo. It’s loved by some for the insights it can provide on a product’s evolution and is used in tech marketing circles. It’s criticized by others for its lack of scientific substance, but even with its subjectivity, it puts words to patterns that can be spotted as concepts and technologies mature. The cycle starts on a growth trajectory toward a peak of inflated expectations, where excessive optimism surrounds the potential of a technology. This is followed by a trough of disillusionment when limitations and misapplications are exposed, leading to a decline in interest. With growing awareness and maturation, the technology can enter the slope of enlightenment. Finally, the cycle reaches the plateau of productivity, where a technology becomes widely accepted, reliable, and integrated into practice. 
 

So, if we hold phytoremediation up to this cycle, what can we see? 

The Rise and Fall 

During the late 1990s, phytoremediation had established practitioners, its own scientific journal, and conferences where venture capitalists flocked, seeking investment opportunities in this potentially revolutionary bio-technology. What started with a few disparate scientists experimenting with plants in the late 1980s had grown into a promising field. Though the audience was small, there was buzz in the scientific and environmental remediation communities. However, as the new millennium began, phytoremediation faced reputational setbacks. Some companies adopted it as a smoke-and-mirrors approach, choosing to plant trees as a cheap alternative to traditional mechanical remediation systems but with little scientific basis to support their claims of functionality. Misguided applications caused doubts to arise about the effectiveness of phytoremediation, leading to a decline in interest and credibility in the early 2000s. 

The Power of Data 

Fortunately, a turning point arrived around 2010 when substantial data on remediated sites started to become available. These tangible results provided evidence that phytoremediation could deliver on its promises, separating it from mere speculation and experimentation. The availability of data made phytoremediation a proven technology, allowing stakeholders to base their decisions on concrete evidence rather than hopeful assumptions. As the 2010s progressed, the field of phytoremediation began to regain momentum and attract renewed interest. 

The Current State of Phytoremediation 

In our assessment, phytoremediation has now entered the slope of enlightenment and is on its way to the plateau of productivity. Experienced practitioners, armed with extensive knowledge and practical understanding, can effectively evaluate site conditions and determine the potential success of phytoremediation. Through years of experimentation and real-world applications, best practices have emerged, reducing the need for pilot systems and enhancing the overall efficiency of processes. 

 
While phytoremediation continues to evolve, there are still areas that require further research. For instance, the treatment of emerging contaminants like PFAS (per- and polyfluoroalkyl substances) remains in the experimental phase, as scientists work to understand their behavior within plant-soil systems. However, for many contaminants, the effectiveness of phytoremediation is well-established. 

An Established Solution 

The journey of phytoremediation exemplifies the Gartner hype cycle, with its initial surge of excitement, subsequent disillusionment, and now the steady ascent towards proven technology. Over the past 25 years, phytoremediation has grown from a concept shrouded in skepticism to a reliable and practical solution for contamination challenges. With a growing body of evidence and the expertise of seasoned practitioners, phytoremediation has become a valuable tool in the environmental remediation toolbox.