Trend of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDFS) in beehive matrices

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/PCDFs) are well-known persistent organic pollutants (POPs) with highly toxic potential. These compounds are released in the environment as a complex mixture of various congeners which shown significant physico-chemical differences, as well as different environmental fates. PCDD/PCDF mixtures change spatially and temporally in the environment and biota, complicating the risk assessment and regulatory control for human and animal exposure. Considering the well-known role of honeybees as bioindicators for pesticides, heavy metals and other chemicals, the present study has been developed to assess the use of honeybees and honeybee products in biomonitoring projects about PCDD/PCDFs. Three Dadant-Blatt type beehives, located since March 2017 in the headquarter of Ducati Motor Holding S.p.A. (Borgo Panigale, Bologna, Italy) have been used as monitoring stations. Honeybees, honey and beeswax have been sampled and analyzed for PCDD/PCDFs detection in June and in September of the same year. Among the analyzed matrices, beeswax has shown the highest WHO-TEQ values, probably due to its lipidic nature capable of accumulating fat-soluble, non-volatile, persistent organic pollutants. Hexaclorodibenzo-p-dioxin (HxCDD), usually measured in vegetables and fruits, has been detected only in honey samples. Maximum levels of PCDD/PCDFs are settled by Commission Regulation (EC) No 1259/2011 of 2 December 2011, but only on animal-derived products. Considering the role of dietary-model adopted by the consumers on toxic substances dietary intake and associated exposure risks, limits on botanical derived products are needed. But more controls about bee-products are advisable also in order to reduce the exposure risk for bees and for protecting biodiversity.