Uptake of some volatile alkyl methylphosphonofluoridates from the vapour phase by wheat plants

Abstract

The uptake of cyclohexyl, isopropyl and 1,2,2-trimethyIpropyl methylphosphonofluoridates from the vapour phase by growing wheat plants was studied. The compounds were absorbed through the leaves of the plants and were degraded in a manner similar to that following their uptake through the roots from hydroponic culture solution. The levels of the methylphosphonic acid derivatives in the plant extracts were influenced by the vapour concentration of the methylpbosphonofluoridate, the period of exposure to the vapour and the state of illumination of the plants, but were not markedly influenced by the chemical nature of the compounds. Likely mechanisms for the uptake are discussed and it is concluded that the main route of absorption involves the stomata. The studies suggest that growing plants can absorb and possibly have a "sink effect" for atmospheric organophosphorus contamination.

Plant Uptake, Transport and Metabolism

“…Entry of pesticide vapors and gaseous air pollutants like sulphur dioxide and ozone occurs primarily through the stomata [24][25][26][27][28]. Consequently, any factor which affects stomatal opening influences the rate of penetration of these substances.…”

Evidence of VX nerve agent use from contaminated white mustard plants

“…Vegetation absorbs nerve agents and their degradation products [19][20][21][22] (but note the paucity of information available). It acts as a time capsule whose interrogation can reveal nerve agent use.…”