The forms of pollution are very numerous and further sources continue to be introduced by new technologies and new lifestyle habits. Air pollution in general has long been suspected of inducing lung diseases as well as allergic, inflammatory and tumor forms, while other diseases such as silicosis (specifically induced by silica dust) and asbestosis (specifically induced by asbestos) are more typical of a polluted occupational environment. It is a well-known fact that the particulate-polluted air the size of 10 microns - the so-called "PM-10" - is dangerous, and the air polluted by "PM-2.5" (dimension less than 2.5 microns ) is even more so. So much so that many countries have already taken legal measures to reduce this presence by limiting in some way the emission of fumes, closing urban areas to cars, etc.

The explosions that can occur in warfare, in military drills, in quarries or in any other environment, conditions and circumstances are an important and aggressive source of pollution. In some cases, the temperature produced as a result of military or industrial processes is sufficiently high to form previously unknown metal-alloy particles, whose effects on the organism have yet to be fully investigated. But natural pollution exists as well. During an eruption of the Etna volcano in Sicily, we found basalt particles on vegetables from the area near the eruption site. Therefore, food can be an additional source of pollution.

Micro and nanoparticles diffused in the atmosphere (by incinerators or industries or other sources) fall to the ground and settle on fruit and vegetables, which become food for men and animals. And pollutants are generally introduced, for example, into flour by the wearing of the grindstones. Very common in the pharmaceutical technique is the use of talc, silica and other inorganic particles added to tablets as excipients and inorganic abrasives for toothpastes and chewing gums. Particles coming from worn orthopedic prostheses, dental ceramics and amalgams can be found in diseased organs. Tobacco smoke also contains inorganic particles and these particles can be both inhaled and absorbed through the oral mucosa. Penetrating the tissues, the particle advances as deep as its dimensions allow and stops only when the filter offered by the tissue is thick enough.