Root-Based Phytostabilization of Thorium and Uranium in Rare Earth Element-Rich Soils

By Pradhananga, Richardson, MirkoueiSustainabilityOct 12, 2026

Score████░░░░░░4.3

VerdictWorth a reader's time today.

Abstract

The expansion of rare earth element (REE) mining has raised concerns about the environmental risks associated with radioactive elements, particularly thorium (Th) and uranium (U), which commonly occur alongside REE-bearing minerals. We investigated the uptake and distribution of Th and U in Pseudoroegneria spicata and Phalaris arundinacea, two grass species previously shown to accumulate REEs effectively. Seven varieties of each species were grown under climate-controlled greenhouse conditions in REE-rich soil collected from the Diamond Creek district near Salmon, ID, USA. Plants were arranged in a randomized complete block design, and Th and U concentrations were analyzed separately in root and shoot tissues. The bioaccumulation factor and translocation factor were calculated to characterize radionuclide uptake and distribution within the plants. Our results showed that P. arundinacea accumulated slightly more Th and U; however, variance due to species was not significant. Tissue type (root vs. shoot) significantly impacted plant Th and U concentrations, with roots accumulating more than shoots for both species. Their limited shoot translocation and preferential root retention indicate potential for phytostabilization, although neither species met hyperaccumulation criteria for Th or U. The life cycle assessment and techno-economic assessment conducted at the greenhouse scale identified electricity consumption as the primary environmental and economic constraint, with a global warming potential of approximately 126 kg CO2-eq and an operating cost of $10,920 per metric ton of soil treated. These findings indicate the potential of P. spicata and P. arundinacea for root-based phytostabilization of Th and U in REE-rich soils.

Sneha Pradhananga, Kathryn Richardson, Amin Mirkouei

The editor's rubric

Heuristic review

Dimension	Level	Weight	What that level means
Leverage	███░░ 3	16%	A method or resource many groups across the field will adopt within a year.
Magnitude	██░░░ 2	20%	Solid incremental gain on a meaningful problem.
Evidence	███░░ 3	20%	Solid: multiple benchmarks or cohorts, ablations, fair baselines, released code or data.
Novelty	██░░░ 2	10%	A new combination of known ideas.
Trajectory	███░░ 3	14%	A clear path to scale.
Stakes	███░░ 3	20%	Meaningful benefit to many people within a few years.

Editor’s rationale

Heuristic triage from title and abstract text only, not a reading of the paper. Cues found: breadth (many tasks); design (randomized); verification (multiple benchmarks); scale (scalable); stakes (global scale, energy, climate).

How the score was computed

rank-2026-10-07

Score████░░░░░░4.3

Score = 10 × (75% × adjusted merit / 10 + 15% × attention + 10% × freshness)

Merit: 5.4 / 10; Weighted rubric, evidence-gated.
Adjusted merit: 4.6 / 10; Shrunk toward the desk prior by editor confidence (44%).
Attention: 0%; Citations, upvotes, points, mentions.
Freshness: 85%; Half-life decay since publication.

Citations0 (reference 15, via openalex, Oct 14, 2026, 07:30 UTC)

The record

Reviewed by heuristic-v6 on Oct 14, 2026, 07:29 UTC. Paper type: empirical.
Categories: Radioactive contamination and transfer, Radioactive element chemistry and processing, Heavy metals in environment, Global and Planetary Change, Environmental Science
TOP, No.4 in the Climate & Energy edition of October 14, 2026.