Lead contamination of small cetaceans in European waters – The use of stable isotopes for identifying the sources of lead exposure

F Caurant (1) , A Aubail (1) , V Lahaye (1) , O van Canneyt (2) , E Rogan (3) , A López (4) , M Addink (5) , C Churlaud (6) , M Robert (6) , Paco Bustamante (1)

1 CRELA - Centre de Recherche sur les Ecosystèmes Littoraux Anthropisés
2 CRMM - Centre de Recherche sur les Mammifères Marins
3 Aquaculture Development Centre
4 Instituto de Investigaciones Marinas (IIM), Eduardo Cabello n°6, E-36208 Vigo, Spain
5 Nationaal Natuurhistorisch Museum
6 CCA - Centre Commun d'Analyses

Lead concentrations and isotopic composition have been measured in bone and teeth of small cetaceans belonging to three species (Delphinus delphis, Phocoena phocoena and Stenella coeruleoalba), to evaluate the toxicological risk and to determine sources of lead in the European waters. Lead concentrations, far lower than threshold value inducing toxic effects in human, were higher in teeth than in bones, but highly correlated between the two tissues (r = 0.92, p < 0.001). Large variations of 206Pb/207Pb values in bone tissue showed that cetaceans must be submitted to various atmospheric influences. No geographical differences appeared which is consistent with studies on their distribution indicating seasonal movements between Brittany waters and the Bay of Biscay. The negative correlation between 206Pb/207Pb ratios and age of the individuals reflected the decrease in the production of alkyl lead in Europe, i.e., the increasing use of unleaded gasoline.

Mots clés: Biomonitoring; Temporal trends; Northeast Atlantic; Common dolphins; Striped dolphins; Harbour porpoises; Heavy metals; Hard tissues; Lead; Biomonitoring

Domaines: Ecotoxicologie

F Caurant, A Aubail, V Lahaye, O van Canneyt, E Rogan, et al.. Lead contamination of small cetaceans in European waters – The use of stable isotopes for identifying the sources of lead exposure. Marine Environmental Research, 2006, 62, pp.131-148. ⟨10.1016/j.marenvres.2006.03.007⟩. ⟨hal-01158371⟩