The European honeybee Apis mellifera L. (Hymenoptera: Apidae) is the most important pollinator worldwide, providing humans an efficient and indispensable service in agriculture as well as in nature. In recent years though, an increasing number of colony collapses and bee death has been observed. The causes are not entirely known, various problems recognized in the past are contributing to the present problem. Amongst others, the extensive use of pesticides in agriculture, combined with monocultures, has proved to have a considerable effect on bee´s health. Direct contamination with the often toxic compounds can cause the death of the animals. There are two main ways pesticides can get in contact with bees: nectar is assumed to contain a lower concentration of the toxic compounds and may cause death or disorientation or the forager bees, entering the digestive system of each animal before it reaches the hive. On the contrary, pollen is collected by the bees on the outside of their bodies, then toxic compounds may be transported within hive, where they can have an impact on a larger number of colony members. In the hive, the stored pollen, called beebread, undergoes a lactic fermentation to allow a better digestion of pollen proteins. For this reason, beebread is recently considered as a rich protein source also for humans, having a higher nutritional value then the pollen loads. However, it is not clear if pesticide residues could be found in beebread as in pollen loads and, in this case, how high the pollution could be. With this thesis, I aim to work on both pollen loads and bee bread, dividing these matrices on the botanical origin and measuring the pesticide pollution of pollen loads and beebread. The samples will be collected in 12 apiaries in May and in July during 2016 and 2017. The pollen species will be identified under the microscope using melissopalynology methods while trace chemical analyses of the bee bread will be done using liquid- and gas-chromatography methods. This thesis project is done in collaboration with the Veterinary Institute of South Tyrol.