Comparison of liquid and comb honeys for pesticide, naphthalene and antibiotic residues

Honey is one of the most natural energy-dense foods and has been used by human beings since ancient times for many purposes mainly nutrition and health. However in order to improve productivity, the use of chemicals has increased significantly during the last decades both in plant production and in beekeeping. The use of pesticides and antibiotics against to bee pests and diseases and naphthalene against to wax moth cause significant residue problems in honey and constitute a potential risk for public health and food security. This study was aimed to determine pesticide, naphthalene and antibiotic residues in honey and to compare these residues in liquid and comb honeys. A total of 60 honey samples were collected by 15 beekeepers that are members of the Regional Beekeepers Association in Antalya (Akseki-Ibradı) and analyzed for 331 pesticide compounds, 25 antibiotic compounds (tetrasiklin and sulfonamid) and naphthalene residues using liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC-MS). Two full frames of comb honey (old, dark and fresh, white) were obtained by same beekeepers directly from the colony. Each full frame of comb honey was divided into two portions to compare residue content between comb honeys and liquid honeys. The first portion of honeycomb was extracted and the second one retained original form. Residues of 331 pesticide compounds, and 25 antibiotic compounds were not detected in the analyzed honey samples. Only three comb honey samples were contaminated with naphthalene at 3.0 µg/kg, 3.9 µg/kg, and 8.9 µg/kg. However, these naphthalene residues detected were below the maximum residue limit (10 µg/kg) prescribed in the Turkish Honey Codex. The absence of naphthalene residues in the liquid honey samples derived from these three contaminated comb honey samples shows that comb honeys carry a higher risk of naphthalene residue than the liquid honeys. In conclusion, some practices such as the training of beekeepers, development of relatively quick and inexpensive residue analyze techniques and strict residue monitoring systems have been effective to prevent residues in Turkish honeys.