Paolo Cabras; M Gisella Martini; Ignazio Floris; Lorenzo Spanedda
Ten honey bee (Apis mellitera Iigustica) colonies were treated with the acaricide cymiazole hydrochloride (Apitol) at the dose recommended for controlling Varroa jacobsoni: 2 g Apitol (17.5% a.i.) in 100 ml of 20% sugar syrup sprinkled on to the combs of each colony. Samples of honey and dead honey bees were collected for up to 112 and 15 days respectively after treatment and analysed using a liquid chromatograph. Cymiazole residues in unsealed honey decreased from an average of 2.45 ppm 1 day after treatment to 0.14 ppm 112 days after treatment: in bees residues were 84.12 ppm after 1 day but decreased quickly and were 0.07 ppm after 15 days. The results suggest that honey bees can rapidly degrade this compound, but that levels higher than the permitted 0.01 ppm (in Italy) can easily occur in honey from treated colonies.