Cleaning Up Soil with Hemp: Phytoremediation

There is a prevailing degradation of soil that has been taking place in America, and across the world, for decades. It has become a widespread devastation specifically in the United States as the desire to drive profits has superseded proper care for fields and attention to soil health. Farmers have been dousing industrial crops in chemical pesticides and herbicides while also eliminating the practice of fallow periods. This has led to a severe decline in topsoil levels, as well as a stripping of nutrients from the earth. The United Nations has acknowledged it as one of the major threats to human health in the coming years (4).

Absorbing Toxins: Understanding Phytoremediation

Hemp could be the answer to the problem of failing soil health. A dense crop with full leaves and sturdy stalks, hemp plants have a relatively high capacity for absorption. Phytoremediation is the term used to describe the act of extracting toxins from the soil using the fast-growing roots of the cannabis plant.

This process was officially discovered and named by Ilya Raskin in the 1990s when he and his team used hemp to clean up the soil around Chernobyl (2). Through this process, toxins are absorbed into the roots of the plants and transformed into a harmless substance (1). Raskin and his team were able to extract radioactive strontium and cesium from the Ukranian soil.

The extraction capabilities were later confirmed by a team of German researchers who successfully decontaminated a field that had been polluted with lead, cadmium, and nickel by an overflow of sewage sludge (2). Now, Italian farmers in Taranto, Italy are turning to hemp to decontaminate their soil after a decade of tainted pastures caused by steel plant runoff had eliminated the space for the grazing of their livestock.

Lifting The Hemp Ban: 2018 Farm Bill

It is clear that hemp holds great potential to mitigate some of the damage done to topsoil in the US, but until the 2018 Farm Bill was passed, the agricultural community was at a standstill on this front. Colorado has led the charge for industrial hemp in many ways, one of which was the first comprehensive study of the cleansing capabilities of hemp on soil. Dr. Elizabeth Pilon-Smits had long been interested in and aware of the phytoremediative capabilities of hemp, but it wasn’t until 2014 that some of the red tape cleared and research surrounding the benefits of hemp crops was encouraged.

Still unable to secure funding for her studies on hemp, it wasn’t until 2017 that Pilon-Smits was approached by Colorado Cultivars with the perfect opportunity to delve into funded research (2). Over the last decade, other states have granted access to researchers via universities to explore the benefits of industrial hemp, and these findings are finally able to be set into motion in many regions across the US as bans are lifted and the growth of industrial hemp is allowed.

Beyond the Farm: Hemp In The City

Another untapped area where hemp could be widely beneficial is in the restoration of brownfields in urban areas across the nation. According to the National Association of Local Government Environmental Professionals (NALGEP) and the Northeast-Midwest Institute (NEMW), there are more than one million brownfields nationwide. Not only are these vacant lots eyesores with hardpacked dirt made up of debris and strewn with weeds, but they are also lost opportunities to utilize land and benefit communities.

Cleansing the soil with hemp plants can rejuvenate the soil on these plots of land to make building easier and urban farming possible where it previously was not (3). Producing localized food for urban communities will help support the ever-expanding population of cities around the US, as well as contribute to cleaner air.

It is important to note that while hemp can clean up soil and groundwater better than most other plants, unmonitored consumption and production of these same crops could pose harm to the user (5). There should be a mindful separation of the crops used for phytoremediation and those processed for consumption to ethically maintain the highest level of health and quality.

Moving Forward With Hemp

With the burgeoning use of industrial hemp to clean up soil worldwide, it can also be used on personal land to stimulate individual agricultural aspirations. Click here to find out more about hemp growing laws in states across the US.

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