Uranium Sources, Uptake, Translocation in the soil-plant System and Its Toxicity in Plants and Humans: A Critical Review

Abstract

Uranium(U) is one of the highly toxic heavy metals and radionuclides that has become a major threat to soil health. There are two types of sources of Uranium in the soil system, natural and anthropogenic. Natural sources of uranium include rock systems and volcanic eruptions while anthropogenic sources include mining activities, disposal of radioactive waste, application of phosphate fertilizers, etc. Uranium accumulation impacts germination, early seedling growth, photosynthesis, metabolic and physiological processes of the plants. Through its accumulation in the aerial parts of the plants, Uranium finds its way to the human body, where it has deleterious health impacts. Different studies have identified the various sources of Uranium, explored, and explained the geochemistry of Uranium in soil, assessed the Uranium uptake and toxicity to the plants, and further studied the impact on human health. Most studies focused on two stages, either soil-plant or plant-human system. However, few studies have critically reviewed and summarized the U in the soil-plant-human system. Thus, the review has been designed to focus on the sources, geochemical behaviour, uptake, and translocation, plant toxicity, food chain entry, and finally, impact on human health. The relationship between the bioavailability of Uranium in the soil-plant system with soil properties like pH, Organic matter, and microorganisms have also been included. The study is further intensified by analyzing the accumulation of Uranium in various parts of the plants.

Foliar application of glycine betaine to ameliorate lead toxicity in barley plants by modulating antioxidant enzyme activity and biochemical parameters

“…In soil, HM concentrations can vary from 1 mg kg −1 to 100,000 mg kg −1 depending on their geological source or human and industrial contamination [8,9]. Soil contaminated with HMs influences the macro and micro-flora [10,11] and recent growth in the literature showed that plant absorbs HMs from the rhizosphere which gets accumulated in the tissue system of plants and affects photosynthetic components, and biomass as noticed in cotton plants [12], rice [13], and pakchoi [14]. In turn, this negatively affects their development, growth, and productivity [15].…”

Uranium Dissemination with Phosphate Fertilizers Globally: A Systematic Review with Focus on East Africa

“…The availability and uptake of non-essential substances like U are influenced by the availability and uptake of important macro and micronutrients like nitrogen (N), phosphorous (P), potassium (K), and zinc (Zn), among others, by plants [64]. The uptake of U by plants may pose both chemical and radiological damage to human and animal tissues [65,66].…”

Uranium and Fluoride Accumulation in Vegetable and Cereal Crops: A Review on Current Status and Crop-Wise Differences

“…These mechanisms effectively impede U translocation from the plant's roots to the shoots. However, U can be transported via two pathways: (1) through the xylem after forming U chelates, such as UO 2 − citrate and UO 2 − lactate, and (2) through symplastic transport (via tiny openings called plasmodesmata that allow for the direct exchange of molecules), where U ions from the roots transfer to the stele, which is facilitated by transpiration [30]. Exposure to certain levels of U has been extensively documented in the scientific literature to have detrimental effects on various plant physiological and genetic processes, including plant seed germination, growth, photosynthesis, nutrient uptake, and genotoxicity [31,32].…”