A research about different residues in pollen and honey samples
Within the cooperative project “Reference system for a healthy honey bee colony – FIT BEE” the subproject “Multifactorial influences on honey bee colonies and establishment of a GIS-based expert information system” was conducted by LAVES Institute for Apidology Celle. The project lasted for four years and was funded by BLE / BMELV. In addition to research about influences of different habitats (city and country sites) on honey bee colonies, residues from Plant Protection Products (PPPs), Heavy Metals and Polycyclic Aromatic Hydrocarbons (PAHs) were analysed in pollen and honey samples. During the project a total of 62 different residues from PPPs were analysed (11 insecticides, 18 herbicides and 33 fungicides) as well as one synergist. Thiacloprid was found in every fourth pollen sample on average with a maximum concentration of 0.16 mg / kg (bee bread). In the country site group and the travel group over 80 % of the pollen samples had PPP-residues, in the city site group 25 % (n = 80 / group, 2012 + 2013). In the country site group 15 active ingredients (a.i.) were parallel in one pollen sample, in the travel group 11 and in the city group 3 with maximum concentrations > 10 mg / kg in pollen samples from the country site. From the 15 pooled honey samples 7 had PPP-residues, especially the spring samples (oil seed rape honey). In all honey samples analysed, four a.i`s were found in the honey samples in total (Thiacloprid (max. 0.05 mg / kg)), Boscalid (0.005 mg / kg), Dimoxystrobin (0.005 mg / kg) and Carbendazim (max. 0.04 mg / kg)). The PPP-data were comparable to the PAH- and the Heavy Metal data: In the pollen samples were more residues and in higher concentration than in the honey samples. Honey is a lipophobic matrix and pollen a lipophilic matrix. Most of the residues solve better in a lipophilic matrix and the bees act as a filter for the nectar / honey.