title: Accumulation of polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyls in livers of young sheep.
abstract: A major part of sheep livers contains levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) above the former but to some extent also the new maximum levels (MLs) in the EU. In order to investigate the relationship between the intake of these contaminants and their accumulation in livers, kidney fat and meat, young blackhead sheep were fed with grass pellets containing PCDD/Fs at 2.5 times the maximum level. Levels of PCDD/Fs in livers were already quite high at the start of the exposure but increased 3-fold within 56d, exceeding the new product based MLs. Levels in meat and fat also increased but did not exceed the MLs. Although less elevated in the grass, both dl- and ndl-PCB levels also increased in liver and fat. Their kinetics in the tissues was less clear, potentially caused by increased levels in the straw given to the sheep during the whole experimental period. There was a clear difference in the behavior of the various congeners, the PCDFs and especially the higher chlorinated PCDFs and PCDDs showing a higher accumulation in the liver. In the case of the PCBs, this was particularly true for PCB 126. When switched to clean grass after 56d, the levels in livers and other tissues decreased to about the levels in the control sheep within 56d. This offers a potential solution for decreasing the intake of consumers.
authors.affiliation: RIKILT Wageningen UR, Akkermaalsbos 2, Wageningen, The Netherlands. Electronic address: ron.hoogenboom@wur.nl.
authors.forename: Ron L A P
authors.initials: RLAP
authors.lastname: Hoogenboom
authors.affiliation: Federal Institute for Risk Assessment (BfR), Berlin, Germany.
authors.forename: Marie Luise
authors.initials: ML
authors.lastname: Stark
authors.affiliation: Federal Institute for Risk Assessment (BfR), Berlin, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Spolders
authors.affiliation: RIVM Institute of Public Health and the Environment, Bilthoven, The Netherlands.
authors.forename: Marco J
authors.initials: MJ
authors.lastname: Zeilmaker
authors.affiliation: RIKILT Wageningen UR, Akkermaalsbos 2, Wageningen, The Netherlands.
authors.forename: Wim A
authors.initials: WA
authors.lastname: Traag
authors.affiliation: RIKILT Wageningen UR, Akkermaalsbos 2, Wageningen, The Netherlands.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Ten Dam
authors.affiliation: Federal Institute for Risk Assessment (BfR), Berlin, Germany.
authors.forename: Helmut A
authors.initials: HA
authors.lastname: Schafft
mesh_terms: D000821:Animal Feed; D000818:Animals; D001572:Benzofurans / Q000032:analysis / Q000493:pharmacokinetics*; D004147:Dioxins / Q000032:analysis / Q000493:pharmacokinetics*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism; D009426:Netherlands; D009929:Organ Size / Q000187:drug effects; D006109:Poaceae / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000493:pharmacokinetics*; D012756:Sheep / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D001572:Benzofurans; D004147:Dioxins; C023614:dibenzofuran; D011078:Polychlorinated Biphenyls; C020887:dibenzo(1,4)dioxin
keywords: Dioxins; Liver; Meat; PCBs; Patterns; Sheep