In view of the growing threat of trace metals to human health, this work set itself the objective of documenting the toxicity of the trace metals most in contact with humans on human health through food. Thus, this study revealed that organic matter, pH and CEC are the main soil parameters that influence the passage of trace metals from soil to plants. The study also revealed that agriculture, industry and road traffic contribute greatly to the input of trace metals into the environment. Regarding the mechanisms of toxicity, the study showed that chromium VI and copper manifested their toxicity by the formation of free radicals after reduction, those of zinc, nickel, manganese and nickel resulting from the disfunctioning of homeostasis. The study showed that lead caused toxic effects by replacing certain cations such as Ca2+, Mg2+, Fe2+, Na+ which have important functions in the cell. Cadmium expresses its toxicity by binding to albumin, thus altering the homeostasis of metals such as calcium. All these mechanisms have revealed both acute and chronic toxic effects.