The declines of pollinator populations present economic and ecological concerns. The use of agrochemicals is one of the contributing factors to wild and managed bee population losses. To understand the risk of pesticide exposure for pollinators, pesticide characteristics must be considered for their persistence and movement in the environment. The honey bee, Apis mellifera, is the model species for tests of bee pesticide risk, but there are other managed bees whose life histories and nesting habitats result in risk outcomes that differ from risks to honey bees. In considering risks for the managed solitary, cavity-nesting bees, Osmia lignaria and Megachile rotundata (Megachilidae), four routes of pesticide exposure are illustrated: larval ingestion, adult ingestion, contact, and transovarial transmission. Several pesticides types and their direct and indirect effects are exemplified for each exposure route. Considerations of techniques and methodologies for studies of pesticide exposure and subsequent effects for these non-Apis bees are highlighted.
