Study of the depletion of lincomycin residues in honey extracted from treated honeybee (Apis mellifera L.) colonies and the effect of the shook swarm procedure.

Bee colonies were treated with 1.2g lincomycin hydrochloride per hive (single treatment in sucrose solution) and samples of honey were then collected at intervals over a 41-week period. The samples were analysed for lincomycin using Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS). The highest mean concentration of lincomycin (pooled analytical results for brood and super honey) was 24 microugg(-1) 3 days after treatment, a mean of 3.5 microgg(-1) after 129 days. The shook swarm procedure was investigated and resulted in a lincomycin concentration of 34 microgg(-1) in honey (pooled results for brood and super honey) 3 days after treatment, declining to 0.38 microgg(-1) 129 days after treatment. Lincomycin was persistent in the hive and detected in all over winter (290 days after dosing) samples of honey collected from both non-shook swarmed and shook swarmed colonies. The results overall indicate that lincomycin parent is a suitable marker compound to detect lincomycin misuse in apiculture.