In vitro and in vivo adsorption studies of diazinon

The in vitro and in vivo adsorption of diazinon to two brands of activated charcoal and locally produced carbon black (N220) has been studied. Solutions of diazinon 10, 20 and 40 micrograms ml-1 were prepared in distilled water and different quantities of adsorbent added. Diazinon-adsorbent slurries were vortex mixed, centrifuged and analysed for free diazinon spectrophotometrically at 241 nm. Small quantities of activated charcoal (AC) and carbon black (CB) showed little or no adsorption of diazinon, while 1000 mg of either AC or CB was able to take up more than 70% at all concentrations of diazinon tested. In acute toxicity tests in mice the optimal adsorbent: diazinon ratio was 8:1 when the animals were treated with 45 mg kg-1 diazinon after immediate, 1, and 3 h post administration of the adsorbent.