Chemical residues in beebread, honey, pollen and wax samples collected from bee hives placed on canola crops in Western Australia

摘要

Samples were collected from bee hives where bees had foraged on genetically modified, seed-treated and non-seed treated canola crops from July to September 2014. Chemical analysis of 240 beebread, honey, pollen and wax samples detected 14 chemical residues with overall detections averaging 1.22 chemicals per sample. Contamination was highest in pollen (2.31) followed by beebread (1.69), wax (1.43) and honey (0.32). The dominant chemicals were the herbicides atrazine and trifluralin, followed by the insecticide chlorpyrifos. Of the seed treatment neonicotinoids, imidacloprid was detected in ten beebread, pollen and honey samples and thiamethoxam was only found in one honey sample. None of the pesticide residues reported from bee hives were likely to pose a risk to honey bees as indicated by a comparison to the LD50 data. From September to December, bee hives produced honey with mean weights ranging from 18.6 to 35 kg/hives.