title: Cadmium accumulation in zebrafish (Danio rerio) eggs is modulated by dissolved organic matter (DOM).
abstract: Experiments were conducted to investigate factors influencing the accumulation of cadmium (Cd(2+)) into zebrafish (Danio rerio) eggs. The accumulation of (109)Cd was affected by: (1) concentration, (2) time, (3) presence of dissolved organic material (DOM), (4) different origin of DOM and (5) different parts of fish eggs. Over a 5-h exposure, zebrafish eggs showed a steady increase in Cd-accumulation. DOM-concentrations over 15ppm carbon (C) decreased Cd-uptake significantly. Both samples of DOM, brown water marsh (LM) and a eutrophic pond (SP), at 16.9ppmC, reduced the Cd-accumulation in the chorion, perivitelline liquid and the embryo. Cd was mainly accumulated in the egg's outer shell chorion (61%) and only small amounts passed through the chorion into the perivitelline liquid (38%) and embryo (1%). In the presence of LM-DOM, the accumulation of Cd into the egg components was decreased by 43% (chorion), 52% (perivitelline liquid) and 52% (embryo), respectively, compared with the control group. Similarly, the presence of SP-DOM reduced the Cd-accumulation by 29% (chorion), 61% (perivitelline liquid) and 60% (embryo), respectively, compared with the controls. DOM-concentration should be taken into consideration when determining ecotoxicological effects of Cd on fish populations.
authors.affiliation: Environment Canada, National Water Research Institute, 867 Lakeshore Road, Burlington, Ontario L7R 4A6, Canada. kent.burnison@ec.gc.ca
authors.forename: B Kent
authors.initials: BK
authors.lastname: Burnison
authors.forename: Thomas
authors.initials: T
authors.lastname: Meinelt
authors.forename: Richard
authors.initials: R
authors.lastname: Playle
authors.forename: Michael
authors.initials: M
authors.lastname: Pietrock
authors.forename: Andreas
authors.initials: A
authors.lastname: Wienke
authors.forename: Christian E W
authors.initials: CE
authors.lastname: Steinberg
mesh_terms: D000818:Animals; D002104:Cadmium / Q000493:pharmacokinetics* / Q000633:toxicity; D002106:Cadmium Radioisotopes; D002823:Chorion / Q000737:chemistry / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004625:Embryo, Nonmammalian / Q000737:chemistry / Q000502:physiology; D005618:Fresh Water / Q000737:chemistry; D006812:Humic Substances / Q000633:toxicity; D010063:Ovum / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D012588:Scintillation Counting; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000378:metabolism*
chemical_list: D002106:Cadmium Radioisotopes; D006812:Humic Substances; D014874:Water Pollutants, Chemical; D002104:Cadmium