Antimony speciation in terrestrial plants. Comparative studies on extraction methods

Area of Science:

• Environmental Science
• Analytical Chemistry
• Plant Biology

Background:

• Accurate antimony speciation in plants is crucial for environmental monitoring, especially in mining-impacted areas.
• Existing extraction methods may not efficiently recover all antimony species for subsequent analysis.
• Understanding antimony's chemical form in plants is key to assessing its bioavailability and ecological impact.

Purpose of the Study:

• To develop and validate a robust extraction method for antimony species in plant materials.
• To compare the efficiency of different extraction systems for antimony recovery.
• To apply the optimized method for antimony speciation in terrestrial plants exposed to mining pollution.

Main Methods:

• Evaluation of various aqueous and solvent extraction systems using Certified Reference Material (Virginia Tobacco Leaves).
• Comparison of extracted antimony with total antimony content determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after microwave-assisted acid digestion.
• Application of the optimized extraction procedure (0.1 mol L⁻¹ citric acid, end-over-end agitation, and sonication) to environmental plant samples.

Main Results:

• 0.1 mol L⁻¹ citric acid with end-over-end agitation (4 h) and sonication (1 h) demonstrated optimal extraction efficiency.
• The optimized method provided reliable antimony speciation data.
• Both inorganic and methylantimony species were detected in the extractable fraction of terrestrial plants from mining-impacted sites.

Conclusions:

• A validated citric acid-based extraction method is suitable for antimony speciation in plants.
• The method allows for the identification of diverse antimony species in environmentally exposed flora.
• This research contributes to improved risk assessment of antimony contamination in terrestrial ecosystems.