Article

Trace element levels in foetus-mother pairs of short-beaked common dolphins (Delphinus delphis) stranded along the French coasts.

Centre de Recherche sur les Ecosystèmes Littoraux Anthropisés, UMR 6217 CNRS-IFREMER-Université de La Rochelle, Université de La Rochelle, 22 Avenue Michel Crépeau, 17042 La Rochelle Cedex, France.
Environment International (Impact Factor: 6.25). 12/2007; 33(8):1021-8. DOI: 10.1016/j.envint.2007.05.008
Source: PubMed

ABSTRACT Tissues of foetus-mother pairs of common dolphins (Delphinus delphis) stranded along the French coasts (Bay of Biscay and English Channel) were analysed for their Cd, Cu, Hg, Se and Zn contents. In the kidneys, foetal Cd levels were extremely low, and strong relationships between Cu and Zn suggested the involvement of metallothioneins since early foetal life. The results also indicated a limited maternal transfer of Hg during pregnancy since levels in the tissues of foetuses were below 1 microg g(-1) w.wt. However, hepatic Hg levels in foetuses increased with body length, and were also proportionate to maternal hepatic, renal and muscular Hg levels. Lastly, affinities between Hg and Se in tissues would participate in Hg neutralisation in both mothers--through tiemannite granules--and fetuses--through reduced glutathione--counteracting the toxic effects linked to the particularly high quantities of methyl-Hg to which marine mammals are naturally exposed.

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