title: Neonicotinoids and bumblebees (Bombus terrestris): effects on nectar consumption in individual workers.
abstract: BACKGROUND
  The objective of this study was to quantify whether the presence of three different neonicotinoid insecticides (imidacloprid, thiamethoxam or clothianidin) in sucrose solution results in antifeedant effects in individual worker bumblebees (Bombus terrestris), and, if so, whether this effect is reversible if bees are subsequently offered untreated feed.
  
  
  RESULTS
  Bees exposed to imidacloprid displayed a significant dose-dependent reduction in consumption at 10 and 100 µg L(-1), which was reversed when untreated feed was offered. No consistent avoidance/antifeedant response to nectar substitute with thiamethoxam was detected at the more field-realistic dose rates of 1 and 10 µg L(-1), and exposure to the very high 100 µg L(-1) dose rate was followed by 100% mortality of experimental insects. No reduction in food intake was recorded at 1 µg clothianidin L(-1), reduced consumption was noted at 10 µg clothianidin L(-1) and 100% mortality occurred when bees were exposed to rates of 100 µg clothianidin L(-1).
  
  
  CONCLUSIONS
  This study provides evidence of a direct antifeedant effect of imidacloprid and clothianidin in individual bumblebees but highlights that this may be a compound-specific effect.
authors.affiliation: Food and Environment Research Agency, Sand Hutton, York, UK.
authors.forename: Helen M
authors.initials: HM
authors.lastname: Thompson
authors.affiliation: Food and Environment Research Agency, Sand Hutton, York, UK.
authors.forename: Selwyn
authors.initials: S
authors.lastname: Wilkins
authors.affiliation: Food and Environment Research Agency, Sand Hutton, York, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Harkin
authors.affiliation: Food and Environment Research Agency, Sand Hutton, York, UK.
authors.forename: Sarah
authors.initials: S
authors.lastname: Milner
authors.affiliation: Centre for Environmental Policy, Imperial College London, Ascot, Berks, UK.
authors.forename: Keith F A
authors.initials: KF
authors.lastname: Walters
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology*; D004435:Eating / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects; D006146:Guanidines / Q000633:toxicity*; D007093:Imidazoles / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000633:toxicity*; D010078:Oxazines / Q000633:toxicity*; D013395:Sucrose; D000077922:Thiamethoxam; D013844:Thiazoles / Q000633:toxicity*
chemical_list: D006146:Guanidines; D007093:Imidazoles; D007306:Insecticides; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D013844:Thiazoles; C480342:clothianidin; C082359:imidacloprid; D013395:Sucrose; D000077922:Thiamethoxam
keywords: antifeedant; avoidance; bumblebees; consumption; neonicotinoids