Toxicokinetics of eight 13C-labelled polychlorinated dibenzo-p-dioxins and - furans in lactating cows

Carry-over of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs) in dairy cows fed smoke contaminated maize silage or sugar beet pulp

“…Various studies have been published in which the carry-over of PCDD/Fs in dairy cows was studied, including studies with single doses of pure (radiolabelled) standards (Jensen and Hummel, 1982;Jones et al, 1987Jones et al, , 1989Olling et al, 1991), or repeated doses of contaminated chemicals like pentachlorophenol (Firestone et al, 1979;Fries, 1999), grass containing background levels (McLachlan et al, 1990;McLachlan and Richter, 1998), grass contaminated by sewage sludge (McLachlan and Richter, 1998), or contaminated feed materials like citrus pulp (Traag et al, 1998) or minerals (Huwe and Smith, 2005). Other studies followed up the depletion of PCDD/Fs on affected farms after removal of the source, like citrus pulp (Malisch, 2000), minerals (Brambilla et al, 2008) or potato peels with kaolinic clay .…”

Scientific Opinion on the risk to public health related to the presence of high levels of dioxins and dioxin‐like PCBs in liver from sheep and deer

“…In lactating sheep, the half-life ranged from 51 days for 1,2,3,7,8,9-HxCDD to 109 days for 1,2,3,4,7,8-HxCDF, and was about half of that in nonlactating sheep (ranging from 95 days for 1,2,3,7,8,9-HxCDD to 226 days for 1,2,3,4,7,8-HxCDF). The authors reported that the half-lives found in non-lactating sheep are somewhat shorter than in nonlactating cows and those in lactating sheep are twice as long as in lactating cows (Olling et al, 1991) which may be explained by assuming a relatively large fat compartment and a relatively low milk fat production rate in sheep as compared to cows. This lower elimination rate of dioxins in lactating sheep, together with the fact that the lactation period of sheep is much shorter than that of cows, so that accumulation of dioxins can take place over a longer period of time, may result in higher concentrations in ewe liver as compared with cow.…”

“…The data reported by Ingelido et al (2009) for sheep milk samples collected in farms located in the vicinity of incineration plants and for samples of feedstuffs used in the investigated farms, are in agreement with these transfer values. Olling et al (1992) investigated the elimination of dioxins in sheep purchased from farms contaminated with dioxin. At the beginning of the experiment animals received for eight days a mixture of dioxins (130 ng International-TEQ 16 /animal per day).…”

Le transfert des micropolluants organiques dans la chaîne alimentaire Etat et perspectives de recherche

“…Les niveaux de dioxines atteints dans le lait peuvent être importants (30 pg TEQ/g MG dans du lait bovin suite à l'exploitation d'incinérateurs d'ordures ménagères hors normes). Les ruminants, ingérant de très grandes quantités de fourrages contaminés par voie aérienne et par les projections de sol lors de pluies, absorberont sur de longues périodes des quantités importantes de micropolluants organiques qu'ils redistribueront en les concentrant dans une faible biomasse adipeuse [29][30][31][32]. La concentration de ces micropolluants lipophiles et rémanents (exprimée par g de matière grasse) a donc tendance à augmenter lorsque les niveaux trophiques croissent (tableau 2).…”

“…Pour l'homme, il est admis que l'exposition moyenne aux dioxines des populations se fait à 90 % par la voie alimentaire [1,[20][21][22][23][24][25][26][27][28][29][30][31][32][33], en particulier par ingestion de graisses animales (lait, produits laitiers, viande, poisson, etc.). Des teneurs moyennes de 30 pg TEQ/g MG ont été observées chez des femmes allaitantes aux Pays-Bas.…”