title: Large-scale monitoring of effects of clothianidin-dressed oilseed rape seeds on pollinating insects in northern Germany: residues of clothianidin in pollen, nectar and honey.
abstract: This study was part of a large-scale monitoring project to assess the possible effects of Elado®(10 g clothianidin & 2 g β-cyfluthrin/kg seed)-dressed oilseed rape seeds on different pollinators in Northern Germany. Firstly, residues of clothianidin and its active metabolites thiazolylnitroguanidine and thiazolylmethylurea were measured in nectar and pollen from Elado®-dressed (test site, T) and undressed (reference site, R) oilseed rape collected by honey bees confined within tunnel tents. Clothianidin and its metabolites could not be detected or quantified in samples from R fields. Clothianidin concentrations in samples from T fields were 1.3 ± 0.9 μg/kg and 1.7 ± 0.9 μg/kg in nectar and pollen, respectively. Secondly, pollen and nectar for residue analyses were sampled from free flying honey bees, bumble bees and mason bees, placed at six study locations each in the R and T sites at the start of oilseed rape flowering. Honey samples were analysed from all honey bee colonies at the end of oilseed rape flowering. Neither clothianidin nor its metabolites were detectable or quantifiable in R site samples. Clothianidin concentrations in samples from the T site were below the limit of quantification (LOQ, 1.0 µg/kg) in most pollen and nectar samples collected by bees and 1.4 ± 0.5 µg/kg in honey taken from honey bee colonies. In summary, the study provides reliable semi-field and field data of clothianidin residues in nectar and pollen collected by different bee species in oilseed rape fields under common agricultural conditions.
authors.affiliation: Institut für Bienenkunde (Polytechnische Gesellschaft), Goethe University Frankfurt, Oberursel, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Rolke
authors.affiliation: tier3 solutions GmbH, Leverkusen, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Persigehl
authors.affiliation: tier3 solutions GmbH, Leverkusen, Germany.
authors.forename: Britta
authors.initials: B
authors.lastname: Peters
authors.affiliation: IPM Impact, Kuringen, Belgium.
authors.forename: Guido
authors.initials: G
authors.lastname: Sterk
authors.affiliation: Institut für Bienenkunde (Polytechnische Gesellschaft), Goethe University Frankfurt, Oberursel, Germany. wblenau@uni-koeln.de.|tier3 solutions GmbH, Leverkusen, Germany. wblenau@uni-koeln.de.
authors.forename: Wolfgang
authors.identifier: http://orcid.org/0000-0002-6874-4730
authors.initials: W
authors.lastname: Blenau
mesh_terms: D000818:Animals; D001516:Bees / Q000502:physiology*; D029688:Brassica napus / Q000737:chemistry*; D004784:Environmental Monitoring; D005858:Germany; D006146:Guanidines / Q000032:analysis*; D006722:Honey / Q000032:analysis*; D007306:Insecticides / Q000032:analysis* / Q000633:toxicity; D000073943:Neonicotinoids; D010573:Pesticide Residues / Q000032:analysis* / Q000633:toxicity; D057048:Plant Nectar / Q000737:chemistry; D011058:Pollen / Q000737:chemistry; D054817:Pollination / Q000187:drug effects*; D012639:Seeds / Q000737:chemistry* / Q000633:toxicity; D013844:Thiazoles / Q000032:analysis*
chemical_list: D006146:Guanidines; D007306:Insecticides; D000073943:Neonicotinoids; D010573:Pesticide Residues; D057048:Plant Nectar; D013844:Thiazoles; C480342:clothianidin
keywords: Bumble bees; Honey bees; Mason bees; Neonicotinoids; Residues; Seed treatment