By using the LC-MS/MS method developed by us, we determined the residual amounts of acaricides in honey samples commercially available in Tokyo from April 2015 to March 2021. The results of analyzing 127 honey samples, amitraz was detected in 85 samples at the level of 1.1-34.1 μg/kg. Propargite was detected in 3 samples at 2.4-3.8 μg/kg. None of them was beyond the Japanese MRLs or uniform limits. In these survey for 6 years, amitraz was detected in high rate throughout the year. But, the present results imply that amitraz has been used properly in actual bee-keeping because of no violation of MRL and less fluctuation in the detected levels. On the other hand, propargite was detected at the levels over LOQ in domestic honey samples for the first time in 2020, which may suggest a new trend of acaricide use in apiculture in Japan.
Keywords: Acaricide; Honey; Internal quality control; LC-MS/MS; Surveillance.