Occurrence of agrochemical residues in beeswax samples collected in Italy during 2013-2015.

Considering the importance of honey bees for pollination activity and biodiversity preservation different studies have dealt with the impact of pesticides on honeybee health. Within the hive, beeswax is a matrix of particular interest because most of the chemicals used in agricultural and beekeeping activities can easily accumulate and persist in this matrix long after treatment has ceased, affecting honeybees survival. However, chemical analyses of pesticide residues in beeswax are not mandatory, so there are no residue limits, for beeswax. The present study was carried out with the aim of investigating the beeswax residue pattern in the Italian hives. 178 beeswax samples collected from 2013 to 2015 were analyzed for 247 pesticides. 73.6% of the analyzed samples reported the presence of one or more pesticides. On average every single sample showed a mean of three different pesticides each with a maximum of fourteen compounds, some of which were banned in Europe or not authorized in Italy. The higher frequencies were associated with three acaricides: coumaphos (60.7% of samples), tau-fluvalinate (50%) and chlorphenvinphos (35.4%), but the higher concentrations were associated to pyrethrins and piperonil butoxide.