title: An exposure study to assess the potential impact of fipronil in treated sunflower seeds on honey bee colony losses in Spain.
abstract: BACKGROUND
  There is great concern about the high losses and strong depopulation of honey bee colonies in some areas of Spain. Some beekeepers have suggested that sunflower seeds treated with the insecticide fipronil could be an important factor in causing those losses. Therefore, an in-depth field study has been carried out in two regions of Spain where sunflower production is intense (Cuenca and Andalucía) and where, for some crops and varieties, fipronil has been used as seed insecticide.
  
  
  RESULTS
  Samples of adult bees and pollen were analysed for bee pathogens and pesticide residues respectively. Neither fipronil residues nor its metabolites were detected in any of the samples analysed, indicating that short-term or chronic exposure of bees to fipronil and/or its metabolites can be ruled out in the apiaries surveyed. Varroa destructor and Nosema ceranae were found to be very prevalent.
  
  
  CONCLUSIONS
  The combination of the two pathogens could augment the risk of colony death in infected colonies, without fipronil residues exerting a significant effect in the given field conditions. Indeed, in this study the losses observed in apiaries located close to sunflower crops were similar to those in apiaries situated in forested areas with wild vegetation.
authors.affiliation: IU CINQUIMA, Analytical Chemistry Group, University of Valladolid, Valladolid, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Bernal
authors.forename: Raquel
authors.initials: R
authors.lastname: Martin-Hernandez
authors.forename: Juan C
authors.initials: JC
authors.lastname: Diego
authors.forename: María J
authors.initials: MJ
authors.lastname: Nozal
authors.forename: Amelia V
authors.initials: AV
authors.lastname: Gozalez-Porto
authors.forename: José L
authors.initials: JL
authors.lastname: Bernal
authors.forename: Mariano
authors.initials: M
authors.lastname: Higes
mesh_terms: D000818:Animals; D001516:Bees / Q000469:parasitology; D006368:Helianthus; D007306:Insecticides / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D011058:Pollen / Q000737:chemistry*; D011720:Pyrazoles / Q000032:analysis*; D012639:Seeds; D013030:Spain; D014887:Weather
chemical_list: D007306:Insecticides; D010573:Pesticide Residues; D011720:Pyrazoles; C082360:fipronil