Toxicological response and bioaccumulation of strontium in Festuca rubra L. (red fescue) and Trifolium pratense L. (red clover) in contaminated soil microcosms

Abstract

Potentially toxic elements (PTE) from industrial activities remain a global concern for their environmental hazards. In particular, strontium is found in drinking water and food, primarily from contamination from the nuclear industry, petroleum extractions, fireworks, and electronics. Its carbonate form is bioavailable and closely resembles calcium; thus, it has become a health concern, and phytoremediation has often been considered for Sr2+. We toxicologically determined Sr2+ tolerance in Festuca rubra (red fescue) and Trifolium pratense (red clover), and their ability to bio-accumulate strontium was compared to the sorption capacity of the soils. These plants were chosen for their ubiquity and as primary colonisers in soils. Experimentally uncontaminated farm soils from Lanarkshire, Scotland, were used, along with these two common plants. Further, seed-germination and plant-growth assays demonstrated that strontium chloride exposures impact both species (0–40mM; p < 0.05). Moreover, translocation factors suggest that T. pratense more efficiently accumulated strontium, and F. rubra has the potential to be the excluder species, which restricts strontium to the roots. This knowledge is relevant to how strontium contamination may be phytoremediated, and suggests using clover during the early stages of ecological succession to sequester strontium from soils.