Cannabis Heavy Metal Pollutants
This study summary provides fact-based answers about the potential for heavy metal contamination in cannabis hemp crops.
- learn exactly how heavy metals pollutants concentrate in hemp and cannabis
- learn how cannabis can be used to clean up mining sites (phytoremediation)
- find out what you need to know if your hemp is grown in contaminated soil
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2019 Study: Cannabis (hemp) Concentrates Pollutants From Growing Environment
- Hemp can clean polluted soils of contaminant heavy metals.
- Consumers of hemp should be conscious of where their hemp comes from since it likely concentrates contaminants from the growing environment. (1)
This 2019 research into hemp and cannabinoids aimed to find out if hemp could be used to clean the environment in polluted industrial areas. (2)
By growing hemp in areas of Pennsylvania polluted by coal mines the researchers aimed to find out if hemp could be used to remove pollutants like heavy metals from the soil. (3)
Types of hemp
Six different varieties of industrial hemp were grown:
- Fedora 17
- Felina 32
- Futura 75
- Santhica 27
- USO 31
- The plants were grown in two different contaminated soil types and two different commercial potting soil types.
- The plants were grown in two environmental conditions (outside and greenhouse). (4)
Researchers conducted a heavy metal analysis of the plants for:
- Seed germination and growth rates were similar for all plants and all soil types however the plants grown in the greenhouse conditions did grow larger.
- Hemp grown in the contaminated soil showed Nickel levels 2.54 times greater than those grown in potting soil.
- Cannabidiolic acid levels were also greatly increased in the plants grown in contaminated soil. (5)
- There was an “18-fold increase in the expression of the cannabidiolic acid synthase gene in plants grown on mine land soil.”
- The study concludes that hemp has a high tolerance to heavy metals. (6)
Learn more about phytoremediation and how hemp may be able to help clean polluted environments.
Husain R, Weeden H, Bogush D, et al. Enhanced tolerance of industrial hemp (Cannabis sativa L.) plants on abandoned mine land soil leads to overexpression of cannabinoids. PLoS One. 2019;14(8):e0221570. Published 2019 Aug 29. doi:10.1371/journal.pone.0221570
Keywords: Cannabis sativa; cannabidiol; hemp; heavy metals;