Guido Rychen, Cyril Feidt, Alain Paris, Henri Schroeder, Beatriz Labelle-Alvarez, Cécile Canlet, Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA), Institut National de la Recherche Agronomique (INRA)-Université de Lorraine (UL), Xénobiotiques, Ecole Nationale Vétérinaire de Toulouse (ENVT), Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National Polytechnique (Toulouse) (Toulouse INP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut National de la Recherche Agronomique (INRA), Méthodologies d'Analyse de Risque Alimentaire (MET@RISK), and Institut National de la Recherche Agronomique (INRA)
International audience; Organic pollutants like PAHs, PCDD/Fs and PCBs can be transferred to the milk of lactating goats after an oral contamination. This study focused on the effects of an oral chronic administration of milk issued from these goats on brain metabolism and behaviour in adult rats. Four groups of rats (n = 12) were treated with methylcellulose 0.3% (MC), non-contaminated milk (NCGM), contaminated milk with PAHs or with a PCDD/F-PCB mixture (PCM). MC or milk were daily administrated during 3 weeks (0.5 ml/100 g bw, p.o.). At the end of the treatment, rats were studied for their locomotor, spatial memory and anxiety performances in an open-field, a T maze and an elevated plus maze (EPM), respectively. Thus, the animals were sacrificed, the brain removed and the tissue analyzed for fingerprinting using the 1H NMR spectroscopy. Urine samples were also collected once a week over the treating period. The multivariate statistical analysis of the 1H NMR spectra of urine discriminated PAH- and PCM-treated animals from controls (MC, NCGM) after 3 weeks of treatment. At the same time, PAH-treated rats exhibited a reduction of the anxiety-related behaviour in the EPM and deficits of spontaneous alternation in the T maze whereas the PCM animals did not. In the brain, PAHs and PCM induced metabolic deviations compared to controls, but these perturbations were different between the two contaminated groups. These results suggest differences in the neurotoxicity of xenobiotics from one group of pollutants to another, and question the toxicity of these compounds through ingestion of contaminated food.