Concentration and movement of diazinon in air

Abstract

The vertical distribution of diazinon in air was measured for 35 days after a label‐prescribed crack and crevice application. Residue levels were higher at floor level than at chest and ceiling heights on day 0, but levels tended to equalize by 7 days. Concentrations were greater at chest and ceiling levels on days 14 and 21, but were equivalent on days 28 and 35. Residues in the adjacent, upper and lower rooms generally were equivalent at all sampling positions and maximum residues occurred in these rooms, and in three other rooms on the same floor level as the treated room, 3 days after application. Low but measurable residues were found in air samples 35 days after application, which indicates that low concentrations of relatively nonpersistent diazinon will remain within structures protected from direct sunlight and ventilation for several weeks.