A proton transfer reaction mass spectrometry based system for determining plant uptake of volatile organic compounds

In order to evaluate the contribution that higher plants make to the removal of volatile organic compounds from the atmosphere, a measurement system consisting of a proton transfer reaction mass spectrometer (PTR-MS), CO2 analyzer, diffusion devise and leaf enclosure was established. The uptake of VOCs by Golden Pothos (Epipremnum aureum) was investigated. The overall relative error associated with measurements made using this system was <2.2% when a Golden Pothos leaf was exposed to 75–750 ppbv of methyl isobutyl ketone (MIBK). Even at the lowest MIBK concentration, more than 2.2% of the inflowing VOC was lost to the leaf, representing a detectable and positive MIBK uptake rate by the plant. The results of the investigation were compared with a measurement system based on gas chromatography analysis and it was shown that the use of a PTR-MS based system can significantly increase the certainties in determining the rate of VOC uptake by plants.