title: Delayed gametogenesis and progesterone levels in soft-shell clams (Mya arenaria) in relation to in situ contamination to organotins and heavy metals in the St. Lawrence River (Canada).
abstract: There is a growing awareness that contaminants in the aquatic environment may alter steroid hormone levels and affect the reproductive success of the invertebrates. To verify if heavy metals and organotins affect sexual maturation in Mya arenaria, individuals were collected from July to November 1998, at different sites along the South coast of the St. Lawrence maritime estuary. Near the Rimouski harbour, clams showed high levels of tributyltin (TBT), DBT in the gonad, along with a lower gonado-somatic index [GSI=gonad wet weight (g)/body wet weight without shell (g)x100], low progesterone levels and a delay in sexual maturation when compared to the reference site. Sites that had intermediate levels of contaminants exhibited intermediate responses of hormones and sexual maturation stages. It is therefore suggested that TBT, DBT are endocrine disruptors in clams. Further studies will however be necessary to investigate in more details how contaminants as TBT can affect the steroid hormones production in the gonads of M. arenaria.
authors.affiliation: Institut des Sciences de la Mer de Rimouski, Université du Québec à Rimouski, 310, allée des Ursulines, Rimouski, Que., Canada G5L 3A1.
authors.forename: A
authors.initials: A
authors.lastname: Siah
authors.forename: J
authors.initials: J
authors.lastname: Pellerin
authors.forename: J-C
authors.initials: JC
authors.lastname: Amiard
authors.forename: E
authors.initials: E
authors.lastname: Pelletier
authors.forename: L
authors.initials: L
authors.lastname: Viglino
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry / Q000187:drug effects* / Q000502:physiology*; D002104:Cadmium / Q000032:analysis / Q000494:pharmacology; D003300:Copper / Q000032:analysis / Q000494:pharmacology; D004784:Environmental Monitoring / Q000379:methods; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005618:Fresh Water / Q000737:chemistry; D005718:Gametogenesis / Q000187:drug effects*; D006066:Gonads / Q000737:chemistry / Q000187:drug effects; D007854:Lead / Q000032:analysis / Q000494:pharmacology; D008297:Male; D008628:Mercury / Q000032:analysis / Q000494:pharmacology; D019216:Metals, Heavy / Q000032:analysis / Q000494:pharmacology*; D009947:Organotin Compounds / Q000494:pharmacology*; D011374:Progesterone / Q000032:analysis*; D011792:Quebec; D012744:Sex Ratio; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000494:pharmacology*; D015032:Zinc / Q000032:analysis / Q000494:pharmacology
chemical_list: D019216:Metals, Heavy; D009947:Organotin Compounds; D014874:Water Pollutants, Chemical; D002104:Cadmium; D007854:Lead; D011374:Progesterone; D003300:Copper; D008628:Mercury; D015032:Zinc