title: Burrowing in the freshwater mussel Elliptio complanata is sexually dimorphic and feminized by low levels of atrazine.
abstract: The widely used herbicide atrazine (ATR) may have endocrine-associated adverse effects, including on behavior. In this study, 120 adult freshwater mussels, Elliptio complanata, were exposed to ATR at the environmentally relevant concentrations of 1.5, 15, or 150 μg/L. Burrowing depth was evaluated hourly for 6 h and at sacrifice animals were sexed by gonad smear. Female controls burrowed overall approximately 30% less than males, the first report of sexual dimorphism in this behavior. Atrazine at 15 μg/L feminized burrowing in both sexes, in that exposed animals burrowed 20% less than their same-sex controls. Males treated with 1.5 μg /L ATR displayed approximately 20-fold higher vitellogenin (VTG) levels than same-sex controls. Higher concentrations of ATR were not associated with increasing effects. A scatterplot showed a weak binomial curve associating low burrowing with high VTG levels. Taken together, these data suggest a nonlinear dose response in behavioral and physiological feminization produced by ATR and support the need to reconsider the widespread use of this compound.
authors.affiliation: a Department of Biology , Adelphi University , Garden City , New York , USA.
authors.forename: Katherine
authors.initials: K
authors.lastname: Flynn
authors.forename: Maria Belopolsky
authors.initials: MB
authors.lastname: Wedin
authors.forename: Josephine A
authors.initials: JA
authors.lastname: Bonventre
authors.forename: Marsha
authors.initials: M
authors.lastname: Dillon-White
authors.forename: Jessica
authors.initials: J
authors.lastname: Hines
authors.forename: Benjamin S
authors.initials: BS
authors.lastname: Weeks
authors.forename: Chantale
authors.initials: C
authors.lastname: André
authors.forename: Martin P
authors.initials: MP
authors.lastname: Schreibman
authors.forename: Francois
authors.initials: F
authors.lastname: Gagné
mesh_terms: D000818:Animals; D001280:Atrazine / Q000633:toxicity*; D001522:Behavior, Animal / Q000187:drug effects*; D049872:Bivalvia / Q000187:drug effects* / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005262:Feminization / Q000139:chemically induced*; D005618:Fresh Water; D006066:Gonads / Q000187:drug effects*; D006540:Herbicides / Q000633:toxicity*; D008297:Male; D012727:Sex Characteristics; D012737:Sex Factors; D014819:Vitellogenins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D006540:Herbicides; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D001280:Atrazine