Variability of residue concentrations of ciprofloxacin in honey from treated hives.
Honey bees (Apis mellifera L.) were treated with a model veterinary drug compound (ciprofloxacin) in a 3-year study (2012-14) to investigate the variability of residue concentration in honey. Sucrose solution containing ciprofloxacin was administered to 45 hives (1 g of ciprofloxacin per hive) at the beginning of the honey flow in late May/mid-June 2012, 2013 and 2014. Buckfast honey bees (A. mellifera - hybrid) were used in years 2012 and 2013. Carniolan honey bees (A. mellifera carnica) were used instead of the Buckfast honey bees as a replacement due to unforeseen circumstances in the final year of the study (2014). Honey was collected over nine scheduled time points from May/June till late October each year. Up to five hives were removed and their honey analysed per time point. Honey samples were analysed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to determine ciprofloxacin concentration. Statistical assessment of the data shows that the inter-hive variation of ciprofloxacin concentrations in 2012/13 is very different compared with that of 2014 with relative standard deviations (RSDs) of 138% and 61%, respectively. The average ciprofloxacin concentration for 2014 at the last time point was more than 10 times the concentration compared with samples from 2012/13 at the same time point. The difference between the 2012/13 data compared with the 2014 data is likely due to the different type of honey bees used in this study (2012/13 Buckfast versus 2014 Carniolan). Uncertainty estimates for honey with high ciprofloxacin concentration (upper 95th percentile) across all hives for 55-day withdrawal samples gave residual standard errors (RSEs) of 22%, 20% and 11% for 2012, 2013 and 2014, respectively. If the number of hives were to be reduced for future studies, RSEs were estimated to be 52% (2012), 54% (2013) and 26% (2014) for one hive per time point (nine total hives).
a Fera Science Ltd, National Agri-Food Innovation Campus , York , UK.
Danny
D
Chan
a Fera Science Ltd, National Agri-Food Innovation Campus , York , UK.
Roy
R
Macarthur
b Food and Environment Research Agency, Sand Hutton , York , UK.
Richard J
RJ
Fussell
a Fera Science Ltd, National Agri-Food Innovation Campus , York , UK.
Jack
J
Wilford
a Fera Science Ltd, National Agri-Food Innovation Campus , York , UK.
Giles
G
Budge
D000818:Animals; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism; D056630:Beekeeping; D001516:Bees / Q000187:drug effects / Q000378:metabolism; D002853:Chromatography, Liquid; D002939:Ciprofloxacin / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism; D005506:Food Contamination / Q000032:analysis*; D006722:Honey / Q000032:analysis*; D006801:Humans; D053719:Tandem Mass Spectrometry; D019155:Veterinary Drugs / Q000008:administration & dosage / Q000032:analysis* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D019155:Veterinary Drugs; D002939:Ciprofloxacin
Ciprofloxacin; apiculture; honey; maximum residue limit; veterinary drug residues