Hemp and sustainability

Industrial hemp refers to cultivars of the Cannabis sativa plant species that are grown specifically for industrial applications. A cultivar is a plant variety that has been cultivated and propagated specifically for desired traits.

Industrial hemp is used for fibre and seed and different cultivars are available dependent on the use. These cultivars are not the same as marijuana or medicinal cannabis and have different chemical fingerprints.

Industrial hemp has been cultivated by humans for thousands of years with thousands of uses across multiple industries. Hemp fibre is used in the textile industry. Hemp fibre is used in construction. It is used to produce lime hemp concrete (hempcrete) and thermal or acoustic fibre-board insulation. These materials are lightweight and breathable and offer resistance to moulds, pests and fire. There is a need to reduce the consumption of energy and emission of greenhouse gases by the construction sector as part of the strategy to achieve carbon neutrality by 2050.

Like other plants, hemp absorbs carbon dioxide as it grows. Using hemp material for long-lasting building materials is an effective way to capture carbon. While release of carbon dioxide will eventually occur when these products reach their end of life, there is tangible benefit in adopting them and delaying the rise in greenhouse gas. There is also the dual benefit of lower emissions during extraction, transportation and manufacturing compared to traditional building materials.

Hemp fibre is used to make paper. The fibre can be harvested after one growing season, can be used without chemical bleaching and is amenable to recycling. Industrial hemp can be used to produce a vast array of biodegradable materials such as bioplastic and bio composites. Hemp bioplastics are both lighter and stronger than PPE polypropylene. Hemp can also be converted to biofuel. It’s easy to see how hemp biobased solutions offer significant sustainability benefits.

Hemp seeds are used for food and feed. Hemp seeds contain high levels of protein and fibre, Omega-3 fats, vitamins and minerals. De-hulled hemp seeds are used for human consumption while whole hemp seeds are used as animal feed. Hemp oil is used in cosmetics and there is demand for hemp extracts containing cannabidiol (CBD) for food and food supplements.

Hemp is grown widely across Europe with France and Germany being the largest producers. Hemp grows rapidly and has a high biomass yield. It can grow up to approximately four metres in four months. Cannabis is called weed as it grows quickly and easily. Hemp cultivation can be more friendly to the land than other crops. It covers the ground quickly preventing soil erosion and requires little intervention with pesticides or herbicides.

Global demand for industrial hemp and its products is growing. In 2018 the global industrial hemp market was valued at $3.43 billion and it is expected to reach $41.78 billion by 2027. This presents an opportunity for producers in Ireland but is not without challenges. There is a need for greater downstream processing infrastructure and unique regulatory considerations apply to the growing and processing of industrial hemp.

Cannabis plants contain compounds called cannabinoids including CBD and delta-9-tetrahydrocannabinol (THC). Selective breeding of Cannabis sativa has resulted in varieties with varying levels of these cannabinoids. Medicinal cannabis, or marijuana, contains significant quantities of THC and it is this compound that gives it psychoactive effects. The level of THC in industrial hemp is too low for the plant to have psychoactive or medicinal effects but it will still contain some THC. As a result, growing of hemp is subject to additional regulatory controls.

Cultivation of hemp requires a licence from the HPRA (Health Products Regulatory Authority). Farmers must use certified seed of varieties listed in the EU common catalogue of varieties of agricultural plant species. In 2024, 116 hemp varieties are registered. The variety of hemp cultivated must have a THC content below 0.3%. Hemp complying with this specification is not used to produce cannabis drug.

THC is controlled under the Misuse of Drugs Act, the primary legislation under which a person can be convicted of a drugs offence in Ireland. There is no exemption under this framework for any quantity of THC in products, causing a barrier for the processing of hemp in Ireland. Hemp farmers may separate the stalk and seeds but must destroy the rest of the harvested plant. This flower head produces the highest levels of cannabinoids in the plant and could be a useful source of these compounds.

If CBD products contain THC, in any amount, they are considered controlled drugs. Other European countries have amended legislation to exempt finished products containing trace amounts of THC to facilitate the production and sale of CBD products.