Determination of pesticides in indoor air and dust

Improved analytical and sampling methods were developed for the multiresidue determination of pesticides in indoor air. Air analysis consists of adsorption of the pesticides in 1 m(3) of air onto Tenax TA via an air sampling pump, desorption with acetone and determination and quantitation by gas chromatography/mass spectrometry (GC/MS) with chemical ionization on an ion trap mass spectrometer. Limits of detection for the 23 pesticides studied ranged from 0.5 ng/m(3) for chlorpyrifos and diazinon to 30 ng/m(3) for o-phenylphenol (approximately 0.5-30 parts per trillion on a w/w basis). A simple method for the detection of pesticides in dust was also developed. This method involves emptying the contents of a vacuum cleaner bag into a standard household food processor and extracting 1 g homogenized dust with acetone before GC/MS. Limits of detection were 25-100 ppb because of interferences by common household chemicals. However, pesticide concentrations were higher in dust than in air, therefore, analysis of dust is a better indicator of indoor pesticide exposure.