Hemp is an amazing plant because there are literally said to be thousands of different uses for it. Some estimates say that there might be as many as 50,000 different ways that we can use hemp to benefit our communities, the economy, and the world around us. Some of the more popularly mentioned uses are medicines, plastics, fuel, livestock feed, and paper products.
One of the even more impressive qualities of hemp is that it can also help to assist with radiation clean-up.
Certain plants and other organisms have been known to clean up toxic soil and groundwater. This is known as bioremediation and is an affordable and ecological method of remediation compared to chemical and mechanical processes. One significant area of research that is currently receiving particular attention is phytoremediation.
Phytoremediation is the intentional use of plants for removal of contaminants in soils, sludges, sediments, surface water and groundwater.
Hemp is an ideal choice for phytoremediation because it is fast growing, has deep roots and is unaffected by the toxins it accumulates from the soil and air. Cadmium, one of the major pollutants in soil, has been shown to be eliminated by simply growing hemp. In fact, certain types of hemp have been studied and recommended for phytoremediation of cadmium, a heavy metal we need to remove. And, while hemp is cleaning the soil, it can act as a carbon sink, to reduce greenhouse gases.
Hemp and the Chernobyl Phytoremediation Project
For almost two decades, industrial hemp growing in the environs of the abandoned Chernobyl nuclear power plant in Pripyat, Ukraine has been helping to reduce soil toxicity.
In 1990, just four years after the initial explosion, the Soviet administration of the time requested that the International Atomic Energy Agency (IAEA) assess the environmental situation. In the 30km exclusion zone surrounding Chernobyl, high concentrations of various toxic metals including lead, cesium-137, strontium-90 and plutonium were found in the soil, as well as in the tissues of plants and animals.
In response, it was decided that a concerted effort to reduce soil contamination through the use of beneficial plants would be undertaken. This process, known as phytoremediation, was implemented almost immediately.
Hemp Provides Hope
In Puglia, Italy, industrial hemp is being used on a wide scale to assist in the decontamination of some of Europe’s most polluted soils. The Ilva steel plant, the largest of its kind in Europe, has poisoned local soil, plants, animals, and human residents for decades with its toxic emissions. Within a 20km radius of the plant, grazing livestock is prohibited.
Since 2012, when the extent of the crisis became apparent, farmers have planted millions of cannabis plants in an effort to decontaminate the soil. In that time, the local area of hemp cultivation has increased from 3 to 300 hectares. Around 100 farmers are growing hemp, and the movement has even proved to be an economic stimulus. A new hemp processing plant has opened to convert the harvest into fibre for clothing and construction.
Since the devastating Fukushima Dai-ichi nuclear power plant accident in 2011, there have been calls for Japan to implement hemp phytoremediation. However, due to the Cannabis Control Law forced into Japanese law by the occupying U.S. powers in 1948, hemp may only be grown under license – and these are highly restricted and difficult to obtain.
A few months after the incident, Fukushima residents began to plant millions of sunflowers, as well as field mustard and amaranth, in an attempt to soak up cesium and other toxins from the soil. The Japan Aerospace Exploration Agency also began an experimental project involving sunflowers in 2011, and various projects since have investigated algae, buckwheat and spinach for their uptake abilities. But it seems that hemp has not been utilized to date.
How Can Hemp From Contaminated Soil Sites Be Safely Used?
In 2012, a Romanian study investigated the nutritional safety of hemp seed produced from plants grown in soils containing cadmium, magnesium, iron and various other metals. The study found that five distinct Romanian hemp strains developed different nutritional profiles according to uptake of the various metals in the soil.
Ominously, all varieties also tested above the safe legal limit for cadmium—despite the soil testing within the safe limit. Levels were particularly high in the Armanca and Silvana strains. Cadmium is a toxic heavy metal that can cause various serious health complications. Excessive dietary intake can lead to joint and bone deformities, respiratory illness, anaemia, and kidney failure.
However, in 2009 another Chinese study showed that cadmium concentration was 25-29.5 times higher in the roots of hemp compared to the shoots, “suggesting the plant can be classified as a Cd excluder”.
Thus, even if hemp used to remove cadmium from contaminated soil is unsafe for consumption, its fibre can still be useful for textile and construction applications. As well as this, hemp biomass can be used in a number of other industrial applications, such as for biofuel.