Keele Research Repository

Bees provide important and economically valuable pollination services to agriculture and other ecosystems. Recent global honeybee declines have been attributed to pesticides, which can ultimately affect the overall functioning and survival of a colony. Various routes of exposure include contaminated beeswax, pollen and nectar. This thesis presents work which examines the presence, accumulation and levels of pesticides found within a number of honeybee related matrices and bumblebee bodies, with four main aims to this study. Firstly, determine which pesticides are contained within beeswax from around the UK. Secondly, monitor which pesticides accumulate in beeswax over a two year period. Thirdly, measure residual neonicotinoid levels in oilseed rape (OSR) nectar and pollen samples. Finally, quantify the levels of thiamethoxam and metabolite clothianidin in bumblebees, following feeding trial exposure, as part of a collaborative study. Analysis was conducted using gas chromatography–mass spectrometry (GC-MS) and quadrupole time-of-flight liquid chromatography-mass spectrometry (Q-TOF LC/MS), utilising the Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction method. Bumblebee samples were extracted using a refined in-house procedure. Results evidenced apiculturally applied chemical treatments to be most likely found in beeswax samples whilst tau-Fluvalinate was most persistent and likely to accumulate in the hive, including foundation wax not exposed to such treatment. Varied levels of neonicotinoids were identified in hand-collected OSR nectar samples; and there require a greater level of analysis, to further understand the implications of these results on UK bees. No quantifiable levels were detected in pollen. Bumblebee analysis determined possible levels of exposure to thiamethoxam during feeding. This thesis provides the first known attempt of identifying pesticide presence and accumulation within UK beeswax, in addition to the levels within UK OSR nectar and pollen. The findings may have wider implications on the beekeeping community. Also presented are various methodologies suitable for future research.