Accumulation of Fluoride by Plants: Potential for Phytoremediation

Abstract

Fluoride pollution is now recognized as a global problem. The reason fluorides are considered as serious contaminants even when they are present at low levels is that they persist for a long time in air, soil, and water and exert negative effects at all levels of an ecosystem. Thus, immediate attention is the need of the hour to remediate the environment from F pollution. Till date, the conventional methods have been developed primarily to remove F from water. These methods are very slow and expensive. Besides, not much research has been done so far to remediate F from soil. This review focuses on the uptake and accumulation of F by certain aquatic and land plant species. Exploring these plants by analysis of their tissues for accumulated contaminants may open up several opportunities to be utilized to remediate F rich water and soil.

Effect of sodium fluoride on germination, seedling growth and photosynthetic pigments in Cicer Arietinum L. and Hordeum Vulgare L.

“…In case of Chickpea treatment with 1.0 and 2.5 mM NaF showed stimulation in total chl (2.98 and 3.06 mg/g, respectively) over the control. This increase of chlorophyll in presence of F is an exception observation and differs from majority of previous studies in range of species 6 including another cultivar (Anuradha) of C. arietinum. 24 In a study on Triticum aestivum, Tomar et al, 25 reported steady increase in the length of root and shoot and chlorophyll contents by 20 and 40 g/ ml NaF.…”

“…In a study with fluoride applied (aerially on leaves and systemically via roots) Vicia faba plants, the ability of roots to accumulate higher amount of F than that of the shoot system was noted, which may well explain as to why in our study we found the roots of barley were relatively more tolerant than the shoots (with biomass production of 116.74 and 116.42 mg) at 1.0 and 2.5 mM NaF concentrations, respectively. 23 This fact also conforms to previous observation of relatively high uptake and accumulation of F in both grass and legume species 6 and may account for higher phytotoxicity to root tissues. Changes in the content of photosynthetic pigments in seedlings obtained on various NaF treatments are summarized in Table 3.…”

“…Certain plant species accumulate F in their roots and shoots at higher concentrations up to 4000 μgg -1 F without showing any signs of toxicity. 6 However, most of other plants show signs of toxicity at relatively much lower F concentration. F affects plant growth and development by interfering with several metabolic pathways associated with photosynthesis, respiration, protein synthesis, carbohydrate metabolism, and nucleotide synthesis.…”

“…F affects plant growth and development by interfering with several metabolic pathways associated with photosynthesis, respiration, protein synthesis, carbohydrate metabolism, and nucleotide synthesis. 7,8 Several studies have been reported on F contamination of soil and its effects on different plant species 6 including cereals 9 and vegetables. 10 However, there is little information available on the effects of F on the germination and early growth characteristics of commonly grown crop plants by farmers.…”

Diagnostic assessment on vegetation damage due to hydrofluoric gas leak accident and restoration planning to mitigate the damage in a forest ecosystem around Hube Globe in Gumi

“…This result means that fluoride damage still persists in this year as well. In fact, fluoride remains for a long time in air, soil and water and exerts negative effects at all levels of an ecosystem (Baunthiyal and Ranghar, 2013). In this respect, a restoration plan to remove those negative effects is needed urgently.…”