Contamination of honey by chemicals applied to protect honeybee combs from wax-moth (Galleria mellonela L.)

Abstract

Greek honey was monitored during a three-year surveillance program for residues of chemicals used to protect honey-bee combs from wax-moth. A total of 115 samples purchased from stores (commercial samples) and 1060 samples collected from beekeepers (bulk samples) were analysed for 1,4-dichlorobenzene (p-DCB), 1,2-dibromoethane (DBE) and naphthalene. A purge & trap-gas chromatograph-mass spectrometer system was used for the analysis. During the first year of the study, 82.9% of the commercial samples had residues of p-DCB that exceeded the established limit of 10 µg kg−1, whilst during the second year 53.6% and during the third 30% exceeded the limit. The percentage of beekeepers samples that had more than 10 µg kg−1 decreased from 46.6 to 34.7% and 39.8% respectively during the three consecutive years of analysis. Only one commercial sample (0.8%) had residues of DBE that exceeded 10 µg kg−1 during the three years study, while 9.9% of the beekeepers samples exceeded this limit in 2003. This percentage fell to 1.9 and 2.8% during the following years. Naphthalene was found in more commercial samples than in samples from beekeepers during the first year, but decreased to similar levels during the next two years. Honeys that are produced earlier in the season are more contaminated those produced later.