Science of the Total Environment 368 (2006) 262 – 270 www.elsevier.com/locate/scitotenv

Mercury distribution in fish organs and food regimes: Significant relationships from twelve species collected in French Guiana (Amazonian basin)
Maury-Brachet Regine, Durrieu Gilles, Dominique Yannick, Boudou Alain * ´
Laboratoire d’Ecophysiologie et Ecotoxicologie des Systemes Aquatiques (LEESA), UMR CNRS 5805, Universite Bordeaux 1, ` ´ Place Dr Peyneau, 33120 Arcachon, France Received 18 October 2004; received in revised form 2 August 2005; accepted 26 September 2005 Available online 2 November 2005

Abstract Within a multidisciplinary research programme set up in French Guiana (Amazonian basin), twelve fish species from six food regimes were collected from the upper part of the Maroni River in order to analyze mercury (Hg) distribution in six organs (gills, liver, kidneys, skeletal muscle, stomach, and intestine) and to look for a relationship between Hg organotropism and food regimes. As many studies have shown, mercury biomagnification leads to extremely marked differences in muscle accumulation levels: the average ratio between extreme concentrations measured in piscivorous and herbivorous species was almost 500. A first principal component analysis on primary Hg concentration variables showed that biomagnification had a marked effect, masking differences between Hg distribution in the organs according to fish species and their food regimes. In order to avoid this, we determined ratios between Hg concentrations measured in the different organs and in the skeletal muscle, considered as the reference tissue for biomagnification effects. A new principal component analysis using these normalized values, in conjunction with a Ward’s hierarchical clustering method, revealed that there is a link between Hg organotropism and the food regimes, with comparatively high [Hg]gills / [Hg]muscle ratios for the herbivorous species; high [Hg]intestine–liver–kidneys / [Hg]muscle