Some of the human activities that are the leading causes of radioactive contamination of soil degradation are nuclear weapons testing, accidental releases, and inadequate radioactive waste disposal practises. According to a new study, a coastal herb can be used to rid the soil around nuclear plants of cesium, a radioactive byproduct of reactors.
Sesuvium portulacastrum, also known as sea purslane, is a salt-tolerant, perennial flowering succulent that grows on sandy coastlines all over the world. The study, published in Advances in Agriculture in October, described it as a cesium "hyper-accumulator" capable of improving soils contaminated by the metal.
"Toxic compounds are rapidly absorbed by Sesuvium plants and translocated to aerial parts such as leaves and stems. That is why we chose the plant for this research,” says T. D. Nikam, author of the study and professor at Savitribai Phule Pune University in Pune, India.
Findings of Study:
According to the study, the presence of radiocesium and other metal toxicants in soil, water, and air can have serious consequences for human health and the environment, and one solution is to use plants for ‘phytoremediation’ of soils. "S. portulacastrum has been extensively researched for its use in phytoremediation of heavy metals such as cadmium, arsenic, lead, nickel, and copper," said Nikam.
The study acknowledges that more research is needed to determine the precise molecular mechanism of cesium tolerance, which may be dependent on the presence of plant-associated microbes. According to S.S. Syamchand, a chemistry researcher and associate professor at the University College of Thiruvananthapuram, the discovery that sesuvium is capable of hyper-accumulating cesium is extremely significant.
Cesium, according to Syamchand, has 40 isotopes (members of an element's family with the same number of protons but different numbers of neutrons in the atomic structure). "The cesium-137 isotope poses the greatest radiation risk because it can cause infertility and cancer," he explained.
"Phytoremediation is widely accepted for removing contaminants from the environment because it is environmentally friendly and cost-effective," says K.C. Jisha, assistant professor of plant science at MES Asmabi College in Kodungallur, Kerala. "The current study's findings should encourage authorities to cultivate S. portulacastrum near all nuclear installations and in contaminated soils," says Jisha, who was not involved in the study.
According to a recent note from the United Nations Food and Agriculture Organization, S. portulacastrum is already being used in some areas for phytoremediation of saline soils and wastewater, as well as for coast erosion protection.
