Concentrations of neonicotinoid insecticides in honey, pollen and honey bees (Apis mellifera L.) in central Saskatchewan, Canada



Neonicotinoid insecticides (NIs) and their transformation products were detected in honey, pollen and
honey bees, (Apis mellifera) from hives located within 30 km of the City of Saskatoon, Saskatchewan,
Canada. Clothianidin and thiamethoxam were the most frequently detected NIs, found in 68 and 75% of
honey samples at mean concentrations of 8.2 and 17.2 ng g1 wet mass, (wm), respectively. Clothianidin
was also found in >50% of samples of bees and pollen. Concentrations of clothianidin in bees exceed the
LD50 in 2 of 28 samples, while for other NIs concentrations were typically 10e100-fold less than the oral
LD50. Imidaclorpid was detected in ~30% of samples of honey, but only 5% of pollen and concentrations
were <LOD in bees. Transformation products of Imidaclorpid, imidaclorpid-Olefin and imidacloprid-5-
Hydroxy were detected with greater frequency and at greater mean concentrations indicating a need
for more focus on potential effects of these transformation products than the untransformed, active
ingredient NIs. Results of an assessment of the potential dietary uptake of NIs from honey and pollen by
bees over winter, during which worker bees live longer than in summer, suggested that, in some hives,
consumption of honey and pollen during over-wintering might have adverse effects on bees.

 

Codling, G., Al Naggar, Y., Giesy, J. P., & Robertson, A. J. (2016). Concentrations of neonicotinoid insecticides in honey, pollen and honey bees (Apis mellifera L.) in central Saskatchewan, Canada. Chemosphere144, 2321-2328.

Concentrations of neonicotinoid insecticides in honey, pollen and bees in central Saskatchewan, Canada..pdf
http://dx.doi.org/10.1016/j.chemosphere.2015.10.135