Bioconcentration factors for volatile organic compounds in vegetation

Area of Science:

• Environmental Chemistry
• Plant Physiology
• Analytical Chemistry

Background:

• Volatile organic compounds (VOCs) are ubiquitous in the environment.
• Understanding VOCs' interaction with plant leaves is crucial for environmental monitoring.
• Existing models predict VOC bioconcentration based on lipid partitioning.

Purpose of the Study:

• To quantify VOC bioconcentration in plant leaves.
• To characterize VOC equilibration between leaves and ambient air.
• To investigate factors influencing VOC uptake and release by different plant species.

Main Methods:

• Air and leaf samples collected at the University of Nevada, Las Vegas campus.
• Analysis of VOCs using vacuum distillation and gas chromatography/mass spectrometry (GC/MS).
• Calculation of bioconcentration factors and partition coefficients (K(oa)).

Main Results:

• Bioconcentration factors for some species align with predictions based on lipid partitioning.
• Certain plant species exhibit significant hyperbioconcentration of VOCs, exceeding theoretical predictions.
• Hyperaccumulating leaves contain high concentrations of monoterpenes, indicating a potential terpenoid compartment.
• VOC uptake by leaves is rapid, with faster equilibration for higher vapor pressure compounds.
• VOC release from leaves is slower in hyperaccumulating species.

Conclusions:

• A terpenoid compartment should be considered for accurate VOC bioconcentration modeling in leaves.
• The findings enhance the characterization of volatile organic compounds in the environment.
• Understanding leaf-air VOC dynamics is essential for ecological and atmospheric studies.