Trisiloxane Surfactants Negatively Affect Reproductive Behaviors and Enhance Viral replication In Honey Bees.

Trisiloxane surfactants are often applied in formulated adjuvant products to blooming crops including almonds, exposing the managed honey bees (Apis mellifera) used for pollination of these crops and persisting in colony matrices like bee bread. Despite this, little is known regarding the effects of trisiloxane surfactants on important aspects of colony health like reproduction. Here, we use laboratory assays to examine how exposure to field relevant concentrations of three trisiloxane surfactants found in commonly used adjuvant formulations affect queen oviposition rates, worker interactions with the queen, and worker susceptibility to endogenous viral pathogens. Trisiloxane surfactants were administered at 5 mg/kg in pollen supplement diet for 14 days. No effects on worker behavior or physiology could be detected, but our results demonstrate that hydroxy-capped trisiloxane surfactants can negatively affect queen oviposition and methyl capped trisiloxane surfactants cause increased replication of Deformed Wing Virus in workers, suggesting that trisiloxane surfactant use while honey bees are foraging may negatively impact colony longevity and growth.