title: Culmination of low-dose pesticide effects.
abstract: Pesticides applied in agriculture can affect the structure and function of nontarget populations at lower doses and for longer timespans than predicted by the current risk assessment frameworks. We identified a mechanism for this observation. The populations of an aquatic invertebrate (Culex pipiens) exposed over several generations to repeated pulses of low concentrations of the neonicotinoid insecticide (thiacloprid) continuously declined and did not recover in the presence of a less sensitive competing species (Daphnia magna). By contrast, in the absence of a competitor, insecticide effects on the more sensitive species were only observed at concentrations 1 order of magnitude higher, and the species recovered more rapidly after a contamination event. The underlying processes are experimentally identified and reconstructed using a simulation model. We conclude that repeated toxicant pulse of populations that are challenged with interspecific competition may result in a multigenerational culmination of low-dose effects.
authors.affiliation: Department of System Ecotoxicology, UFZ - Helmholtz Centre for Environmental Research , Permoserstrasse 15, D-04318 Leipzig, Germany. matthias.liess@ufz.de
authors.forename: Matthias
authors.initials: M
authors.lastname: Liess
authors.forename: Kaarina
authors.initials: K
authors.lastname: Foit
authors.forename: Anne
authors.initials: A
authors.lastname: Becker
authors.forename: Enken
authors.initials: E
authors.lastname: Hassold
authors.forename: Ida
authors.initials: I
authors.lastname: Dolciotti
authors.forename: Mira
authors.initials: M
authors.lastname: Kattwinkel
authors.forename: Sabine
authors.initials: S
authors.lastname: Duquesne
mesh_terms: D000818:Animals; D003465:Culex / Q000187:drug effects; D003621:Daphnia / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D010575:Pesticides / Q000633:toxicity*
chemical_list: D010575:Pesticides