One of the main outcomes of the eleven meetings of the Working Party was the recognition of the importance of interdisciplinary studies linking regional geochemistry with plant, animal and human health. The effects of major element deficiencies or excesses on plant health are well known; this is not the case for trace elements. In fact, rapid and reliable analytical methods for determining trace element abundances have only recently become available, and it is to be expected that important new information on trace element levels will be forthcoming. This, however, is only part of the problem...