Triazophos residues and dissipation rates in wheat crops and soil.

The residual level and dissipation rate of triazophos in wheat crops and the soil in which they were grown were determined by gas chromatography (GC). Maximum final residues of triazophos in wheat grain, stems and leaves, and soil were 1.865, 44.506, and 0.973 mg/kg, respectively. The mean half-life of triazophos in wheat plants (grain, stems, and leaves) was 5.22 days with a dissipation rate of 90% over 14 days. The half-life in soil was 7.93 days with a dissipation rate of 90% over 21 days. Dissipation rates in two geographically separated experimental fields differed, suggesting that this was affected by local soil characteristics and climate. Although residual levels of triazophos in wheat plants may pose risks to the health of humans and other animals, comparatively low residues in soil suggest that this pesticide may be otherwise environmentally safe.