Survey of acaricide residues in Italian organic and conventional beeswax

Kurzfassung

According to EU Regulation 1804/99, beekeepers converting to organic production methods must replace old combs, which contain residues of lipophilic acaricides used to control infestation of Varroa destructor, with residue-free wax. This poses problems due to difficulty in obtaining organic wax, passage of residues from old wax to new residue-free foundations and the risk of contamination of foundations in the wax transforming firms. To monitor the residue levels of Italian beeswax, samples produced between 1990 and 2006 were analysed for residues of most commonly used acaricides. The samples analysed for the two most commonly used active ingredients, coumaphos and fluvalinate, were classified according to the production method (organic, conventional or converting) and according to the kind of wax (melted or foundation). For all the considered a.i. the average levels of residues in all kinds of samples (organic and conventional) grouped by year, decreased during the considered time period. Classification according to production method showed that organic beekeeping practices have definitely reduced levels of residues, although these persist in wax for a long time. Average levels of acaricide residues in organic melted cap beeswax were used by most Italian Control Bodies for fixing thresholds levels for use of wax in organic beekeeping (200ppb for coumaphos and 100ppb for fluvalinate).