Abstract
A method was developed and validated for the determination of diazinon levels in indoor air in which a solid sorbent tube packed with Supelco-20P for sample collection was used. Analysis was by capillary column gas chromatography coupled to a nitrogen-phosphorous selective detector. Recoveries of diazinon from air were 90% or better for air levels of 0.1 and 1 µg/m3. Diazinon was trapped efficiently by the sorbent even under conditions of elevated temperature and humidity and in the presence of high levels of hydrocarbons. Diazinon can be converted to diazoxon under some sampling conditions; this can be of major significance at low (0.1 g/m3) diazinon air levels. Diazinon air levels were monitored in an animal facility treated monthly with an aqueous diazinon formulation. Air levels of diazinon increased after application but within one day had decreased to 2 to 3 µg/m3. Levels continued to decline to approximately 0.5 µg/3 until the next application. Background air levels did not appear to increase with repeated monthly applications.