The dioxin reference program is founded on a decision by the 37th conference of Federal and Länder Ministers for the Environment of the Federal Republic of Germany, 21-22 November 1991. At that time, there were calls for further studies in improve the data on dioxins in soil, water, air, foodstuffs and feedingstuffs, for the initiation and coordination of future government and Länder measuring programs and for a centralized documentation and evaluation of the results.