Case Study: Beehive Devastation by Microencapsulated Parathion-Methyl

• DOI: 10.1007/s10337-016-3027-y
• Publication Date: 2016-01-20T16:01:37Z
• Authors: Silvina Niell; Natalia Gerez; Florencia Jesús; Verónica Cesio; Horacio Heinzen
• Keywords: Beehive; Parathion methyl; Parathion

During spring 2012, massive honeybee mortality was observed within 2000 beehives in southwest Uruguay. The incident was presumed to be due to pesticide applications in the hives surroundings. To find the causative agent, bees were analyzed by gas and liquid chromatography coupled t o mass spectrometry, employing a method reported by our group that has been expanded to 39 compounds. The new scope includes parathion-methyl, which was found at an average 0.48 µg bee−1, ten times higher than the LD50 for bees. Parathion-methyl is only allowed to be sold as microcapsules, a slow release formulation type with 80–50 µm particle diameter. Surprisingly, it was stated that parathion-methyl microcapsules were applied in the zone but 1000–2000 m ahead from the affected hives. This fact was not only a confirmation of the distances bees can fly from the hive, but also demonstrated that the microcapsules, mistaken for pollen, were transported to the hive where the toxic was released. Although microcapsules have environmental advantages as a pesticide delivery system they can threaten honeybees’ survival.