Phytoremediation: Harnessing Plants to Clean Polluted Soils
Industrial pollution has left many regions worldwide—especially in Eastern Europe and Asia—grappling with heavy metal contamination in their soil. This poses serious risks to human health, as toxic metals can enter the food chain through crops grown in polluted areas. Scientists are exploring a promising, plant-based solution known as phytoremediation, which uses certain plants to absorb, store, or stabilize contaminants in the environment.
A key review paper, "Phytoremediation: Novel Approaches to Cleaning Up Polluted Soils", written by Ute Krämer in 2005, explores how genetic modifications can enhance plants' ability to remove heavy metals from soil. Krämer, a leading researcher in plant physiology at Ruhr University Bochum, discusses two main strategies:
Phytostabilization: Instead of removing metals, plants cover the contaminated soil to prevent wind or water erosion from spreading pollutants. This helps contain toxic elements in one place.
Phytoextraction: Plants absorb metals through their roots and store them in their leaves and stems. Once these plants are harvested, the contaminants are removed from the soil.
To improve these processes, scientists are using genetic engineering to enhance plants' ability to tolerate and accumulate metals. Some strategies include:
Inserting bacterial genes that help plants take up mercury-containing compounds.
Using biological encapsulation to prevent modified genes from spreading to wild plant populations.
Studying hyperaccumulators, plants naturally capable of storing high levels of metals without harm, to identify key genes responsible for this trait.
Applying genomic approaches to discover multiple genes involved in metal regulation and tolerance.
By refining these methods, researchers hope to develop plants that can effectively transfer harmful metals from the soil—where they pose risks to human health—into plant tissues, offering a cost-effective and sustainable solution for pollution cleanup.
References:
Kramer, U. (2005) Phytoremediation: Novel Approaches to Cleaning up Polluted Soils. Current Opinion in Biotechnology, 16, 133-141.
Zhakypbek, Y., Kossalbayev, B. D., Belkozhayev, A. M., Murat, T., Tursbekov, S., Abdalimov, E., Pashkovskiy, P., Kreslavski, V., Kuznetsov, V., & Allakhverdiev, S. I. (2024). Reducing Heavy Metal Contamination in Soil and Water Using Phytoremediation. Plants, 13(11), 1534.