Risk of residues of toltrazuril sulfone in eggs after oral administration -Could setting maximum residue limit be helpful?

摘要

A depletion study of toltrazuril and its metabolites was performed using 20 hens medicated via drinking water for two days in a dosage of 7 mg kg- 1 per kg body weight. Afterward, eggs were collected for 42 days. Residues were analyzed in whole eggs and yolk and whites. Toltrazuril sulfone was found to be the most predominant in all matrices, the highest concentration was found in the yolk & ndash; 5567 & micro;g kg- 1, followed by whole eggs samples & ndash; 4767 & micro;g kg- 1 and egg whites & ndash; 532 & micro;g kg- 1.On last day toltrazuril sulfone were still detected & ndash; 22.5 & micro;g kg- 1. 70 days is required to concentration of toltrazuril sulfone reach zero. Administrating toltrazuril before the laying phase can pose a risk of residues of toltrazuril sulfone in eggs. Setting Maximum Residue Limit could reduce the risk of non-complaint samples and ensure the safety of consumers, but still requires 44 days of the withdrawal period.