Access to high-quality potable water varies widely around the world. Almost all populations in industrialized countries in the Northern Hemisphere have the benefit of clean water and wastewater evacuation and treatment systems. Inhabitants of the poorest regions of the globe, on the other hand, are very often deprived of such services, and they are exposed to all sorts of diseases. Clean water is an essential component of public health. It is estimated that 25 million deaths each year can be attributed to unhealthy water, whether through infectious diseases (cholera, typhoid, dysentery, hepatitis) or parasitic diseases (malaria, schistosomiasis, etc.). On the other hand, coastal pollution, due to individual waste, agricultural products, and urban effluents, is localized mainly in the wealthy regions of the world (North Sea, Gulf of Mexico). The Mediterranean Sea is also the site of both eutrophication and hydrocarbon pollution.