The project will evaluate farmer exposure to crop protection products. In France, data has not been compiled regarding the issue of exposure to plant protection products. The French institute of sanitation monitoring (“Institut de veille sanitaire” –InVS-) and a team from the University Claude Bernard Lyon 1 have thus set the Matphyto program in motion. This program will produce a method to evaluate retrospectively work related exposure to crop protection products through crop/exposition matrixes. Database matrixes will distinguish exposition according to the main crops grown in France and according to the main categories of crop protection product (herbicides, insecticides, fungicides…), broken down according to their chemical composition (synthetic plant hormones, organophosphates…) and specific active substances contained. A set of indicators (probability, frequency and intensity) will enable us to estimate the exposition in chronological way. The creation of these matrixes require collecting and compiling data on the current and past use of plant protection products as well as the contribution of professionals and their experience on the field. The Agreste data we asked will enable us to match population data with that of crop fields which are compiled in our crop/exposition matrixes. From these sources, estimates on the prevalence of exposition to the crop protection products relating to professional factors or main crop can be calculated.