title: Neonicotinoid Residues in Wildflowers, a Potential Route of Chronic Exposure for Bees.
abstract: In recent years, an intense debate about the environmental risks posed by neonicotinoids, a group of widely used, neurotoxic insecticides, has been joined. When these systemic compounds are applied to seeds, low concentrations are subsequently found in the nectar and pollen of the crop, which are then collected and consumed by bees. Here we demonstrate that the current focus on exposure to pesticides via the crop overlooks an important factor: throughout spring and summer, mixtures of neonicotinoids are also found in the pollen and nectar of wildflowers growing in arable field margins, at concentrations that are sometimes even higher than those found in the crop. Indeed, the large majority (97%) of neonicotinoids brought back in pollen to honey bee hives in arable landscapes was from wildflowers, not crops. Both previous and ongoing field studies have been based on the premise that exposure to neonicotinoids would occur only during the blooming period of flowering crops and that it may be diluted by bees also foraging on untreated wildflowers. Here, we show that exposure is likely to be higher and more prolonged than currently recognized because of widespread contamination of wild plants growing near treated crops.
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Cristina
authors.initials: C
authors.lastname: Botías
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Arthur
authors.initials: A
authors.lastname: David
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Julia
authors.initials: J
authors.lastname: Horwood
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Alaa
authors.initials: A
authors.lastname: Abdul-Sada
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Nicholls
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Hill
authors.affiliation: School of Life Sciences, Sussex University , Falmer BN1 9QG, U.K.
authors.forename: Dave
authors.initials: D
authors.lastname: Goulson
mesh_terms: D000691:Anabasine / Q000633:toxicity*; D000818:Animals; D001516:Bees / Q000378:metabolism*; D029741:Brassica rapa / Q000737:chemistry; D018556:Crops, Agricultural / Q000737:chemistry; D004781:Environmental Exposure / Q000032:analysis*; D035264:Flowers / Q000737:chemistry*; D001467:Hordeum / Q000737:chemistry; D007306:Insecticides / Q000032:analysis; D057048:Plant Nectar / Q000737:chemistry; D011058:Pollen / Q000737:chemistry; D012639:Seeds / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D014908:Triticum / Q000737:chemistry
chemical_list: D007306:Insecticides; D057048:Plant Nectar; D012987:Soil; D000691:Anabasine