Effect of heat treatment on milk contaminated with diazinon as an environmental pollutant

ABSTRACT

The present study was designed to throw light on monitoring Diazinon residues in milk of lactating cows sprayed once with diazinon as 0.1% solution of Neocidol as well as on the effect of heat operations on these residues in accordance to its level in fresh milk within a withdrawal study. Depletion of Diazinon residues in milk was monitored 1, 7 and 15 days following exposure. Diazinon appeared in the milk during the first milking 24 hours post-spraying in fresh milk, exceeding the in-term tolerance established by FAO/WHO. A substantial portion of Diazinon incorporated in fresh milk was converted to metabolite and disappeared during heat processes. Authors attributed most of the pesticide loss to removal associated with leaching of the fats in milk. The disappearance order of Diazinon as a result of pasteurization at 62.8C for 30 min. or boiling for 60 seconds in comparison to the concentration in fresh milk was boiling > pasteurization. In respect to the withdrawal study, the occurrence and incidence of Diazinon residues in milk had been largely lacking. It was no longer present 15 days after exposure