International Journal of Science and Knowledge ISSN: 2322-195X Vol. 3; No. 1; 18-26 (2014) Tissular distribution of heavy metals in the mugil cephalus of the moulay Bousselham lagoon (Morocco) Abdelouahed Meissara 1 , Mohamed Fekhaoui 1 , Mohamed El Morhit 1* , Matthieu Waeles 2 , Abdellah El Abidi 3 and Ahmed Yahyaoui 4 1 Pollution, Ecotoxicology and Sanitary Risks Unit, Scientific Institute, University Mohammed V–Agdal. Ibn Battuta Av, BP 703. Agdal, Rabat, Morocco 2 Chemistry laboratory Navy, UBO and UMR CNRS 7144, Place Nicolas Copernic, 29280 Plouzané, France 3 Ecotoxicology Department, National Hygienic Institute, Morocco 4 Mohammed V–Agdal University, Faculty of sciences, Department of biology, B.P. 1014, Rabat, Morocco Email: morhit_med@yahoo.fr Abstract he survey of the tissular distribution of heavy metals in the Mugil cephalus fish of the Moulay Bousselham lagoon shows very important spatial variations and interesting organotropism. The spatial analysis of iron, zinc, copper, aluminium and lead indicates that the fish under the influence of the Drader River, contain high contents of copper, aluminium and lead whereas the organisms under the influence of the Nador Channel contain high contents of zinc. The Study of the tissular distribution of heavy metals in gills, liver, kidney and stomach of the mule shows that the accumulation of zinc, copper and iron is not very important in these four organs in spite of some spatial differences. But the accumulation of aluminium and lead, essentially in the gills, indicates the recent character of this metallic contamination (freeway, fertilisers... etc). Introduction he Moulay Bousselham lagoon, commonly called Merja Zerga, constitutes an ecosystem with varied natural resources. The exploitation of these resources (fishing, aquaculture, etc) holds a good place in the regional economy and life of thousand of residents. This very coveted medium is often the site of an intense degradation (contributions of polluted water, agriculture, etc). This is more regrettable as this ecosystem presents ecological, faunistic and floristic originalities which make it a site of international interest (site RAMSAR) whose safeguarding becomes urgent. Hydrology of this lagoon, dependents on the influence of the tides, is largely controlled by the contributions of fresh waters of the Drader River (river of average importance) and of the Nador channel; where draining water is channeled through a series of irrigation canals to the rice plantations in the southern part of the lagoon. These contributions of fresh waters carry a large quantity of chemical and organic substances (natural and artificial) towards the lagoon contributing to the distribution and accumulation of many elements traces such as heavy metals, in the various components of this ecosystem particularly ichthyofauna (Hmama, 1999; MedWet, 1999; Mergaoui, 2004). The presence of these elements traces of specific toxicity constitutes not only a problem of the environment safeguarding but also a public health problem (El Morhit et al., 2012). T T