Fish is the most preferred and consumed food by humans because it is a source of protein, vitamins and energy with low fat and calorie content. The risks of chemical contamination of foods for human health are recognized as one of the most important issues related to the consumption of aquatic foods, especially the toxicity associated with contamination by dangerous chemicals. The risk of this toxicity increases their dangers globally and at a remarkable trend. The development projects whose estuaries have been the subject of several studies since the middle of the last century because of their impact on the environment, in addition, the profound modification which has modified not only the geometry of the estuaries, but also natural hydrological and sedimentological processes. The objective of our research work is to study the impact of these development projects in estuaries (Bouregreg estuary as an example) on the accumulation of heavy metals in fish of aquatic origin. These studies were largely carried out within the framework of guaranteeing health safety on the one hand for fish and on the other hand for human beings.