The film illustrates five years of research by the Work Group of Contamination of Remote Areas, a team of environmental toxicologists from the universities of Sienna and Milan. With a number of expeditions to remote regions in various continents, the group has contributed to the knowledge of the minimal levels of pollution in the world. The Nepalese Himalaya, Mount Kenya, Greenland and Antarctic are some of the areas studied and reached respectively with the techniques of alpinism, skiing, dog sledges or polar navigation with sails.