Abstract
The opening lecture provided a chronological overview of the risks that have weighed or are still weighing on human health, from the epidemic-war-famine trilogy, which has gradually and partially faded away, to the so-called " lifestyle factors " (tobacco, alcohol, dietary imbalances, sedentary lifestyle) and physico-chemical agents. Our movement, centrifugal in relation to the patient and the onset of disease, has been to move from listing the causes of death to identifying the causes of causes. Infectious diseases, the development of which may have been encouraged by the invention of agriculture, which brought humans and domestic animals closer together, fostering zoonoses, were until the beginning of the 20th century the major cause of mortality in Europe. With the gradual control of these diseases in northern countries came an epidemiological transition that led to a spectacular threefold increase in life expectancy in three centuries (from around 25 years before the French Revolution to 82 years today in France). This is due to a reduction in mortality from infectious diseases, which often occur at an early age, and their gradual replacement by chronic diseases, which generally occur at an older age. We recalled the contribution of genetic polymorphisms and lifestyle factors to the onset of chronic diseases, which is real but quantitatively limited for the most frequent chronic diseases. We then reviewed the modifications to our environment during the Anthropocene (concerning chemical substances, diet, tobacco, etc.) and discussed the general elements in favor of an effect of the physico-chemical environment on the onset of these chronic diseases, including the fact that certain environmental factors can induce the pathophysiological mechanisms involved in many chronic diseases. Finally, we have discussed more specific arguments in the same direction, based on recent methodological developments, both in the field of toxicology and, in humans, of exposure biomarkers and causal inference (Judea Pearl), which provides a rigorous framework for identifying the causes of disease in a non-experimental approach.
