Determination of Chlorpyrifos and its Metabolite 3,5,6-Trichloro-2-Pyridinol in Tap Water and Bananas by Quantitative TLC on Preadsorbent Silica Gel

摘要

Chlorpyrifos insecticide and its metabolite TCP were determined in tap water and banana samples by TLC of extracts on preadsorbent silica gel layers, detection with silver nitrate reagent, and densitometric scanning. Cleanup steps were required for the fruit sample extracts. Recovery of chlorpyrifos from tap water at 5 ppb averaged 87.5 and from banana at 0.05 ppm was 84.6. Recovery of TCP from water at 5 ppb averaged 84.0 and from banana at 0.05 ppm was 86.8. The sensitivity and precision of the method were shown to be adequate for routine residue analysis.