Two groups of honeybees were exposed to orally administered, low level doses of formulation and technical grade chlorothalonil (approximately 2µg/bee/day) continuously over a three day period. Excreta samples were collected every 24 hours, along with mortality data. Following collection, excreta were extracted, and samples analyzed using LCMS-UV/Vis spectroscopy. In two separate trials, the mortality rate among the group that received the formulation dose was at least four times higher than the technical and control dose groups. A significantly higher mortality rate was observed during the 24-48 hour time period than during the 48-72 hour time period. Photodiode array (PDA) data demonstrates significant differences in the chemical profile of excreta samples collected at 24 and 48+ hours, suggesting a correlation with observed mortality. PDA and LC-MS data also confirm the presence of chlorothalonil in collected wax chips.
