Uptake of Aldehydes and Ketones at Typical Indoor Concentrations by Houseplants

The uptake rates of low-molecular weight aldehydes and ketones by peace lily (Spathiphyllum clevelandii) and golden pothos (Epipremnum aureum) leaves at typical indoor ambient concentrations (10¹−10² ppbv) were determined. The C3−C6 aldehydes and C4−C6 ketones were taken up by the plant leaves, but the C3 ketone acetone was not. The uptake rate normalized to the ambient concentration C_a ranged from 7 to 19 mmol m⁻² s⁻¹ and from 2 to 7 mmol m⁻² s⁻¹ for the aldehydes and ketones, respectively. Longer-term fumigation results revealed that the total uptake amounts were 30−100 times as much as the amounts dissolved in the leaf, suggesting that volatile organic carbons are metabolized in the leaf and/or translocated through the petiole. The ratio of the intercellular concentration to the external (ambient) concentration (C_i/C_a) was significantly lower for most aldehydes than for most ketones. In particular, a linear unsaturated aldehyde, crotonaldehyde, had a C_i/C_a ratio of ∼0, probably because of its highest solubility in water.