Distributed across the various environmental compartments, these substances pose grave problems to plants, animals and man in so far as their accumulation may have consequences that are both unforeseeable and difficult to evaluate. A study on heavy metals in the various environmental compartments showed the decisive role played by human activity in the global cycle of these elements. The main sources of anthropic pollution are the chemical, engineering and metalworking industries, power stations, domestic heating installations and the internal combustion engine .
In addition to the pollution levels recorded in densely populated and industrial areas, consideration must also be given to the dispersion of contaminants in the air and their transportation beyond national borders, possibly to remote areas devoid of direct anthropic pressure (e.g. Antarctica). In view of the quantities of pollutants and the area concerned, evaluating air pollution and contaminant fallout requires new monitoring instruments to work alongside and, in some cases, replace, traditional methods.