Heavy metals are among the most harmful contaminants in the ecosystems due to their persistency, bioaccumulation and high toxicity. In this chapter, we presented the sources, distribution and pathways of heavy metals in soil, water and air. The physico-chemical properties, uses, toxicity and health hazards of the purely toxic heavy metals lead, cadmium and mercury were also described. Other essential heavy metals were briefly presented and the main health effects due to their deficiency or excess were displayed in this chapter. Finally, the various methods used for the removal of heavy metals from soil and aquatic environments were discussed with a focus on nanomaterials.
Part of the book: Environmental Health
Vitamins are organic substances that are essential for normal metabolism, growth, development, and regulation of cell function. Mineral elements are non-organic substances. They constitute 4% of the body mass. Multivitamins and minerals are commonly used as dietary supplements to maintain good health and prevent chronic diseases. In this chapter, we described selected vitamins and minerals used as nutritional supplements. We presented their dietary sources as well as their absorption, metabolism, storage and functions in human body. We also discussed their benefits and potential harmful effects associated with deficiency or excess intake. The prevalence, recommended intakes, regulatory status and health effects of supplementation with these micronutrients were also detailed. Finally, the use of vitamins and minerals as food additives was described in this chapter.
Part of the book: Natural Food Additives