註釋 Proceedings of a symposium on the Use of Nuclear and Related Techniques for Studying Environmental Behaviour of Crop Protection Chemicals jointly organized by the IAEA and FAO, Vienna, 1-5 July 1996. Use of pesticides has become an integral component of agricultural systems worldwide. Concerning the environment, information must be provided before a product is registered in order to provide assurance that it can be used without unacceptable hazard to non-target organisms. In addition, post-registration surveillance and monitoring studies are necessary to check that the fate and environmental effects of pesticides under field conditions are consistent with predictions. Much of the data are generated using radioisotopes and other nuclear or related methods. Developing countries often have to rely on data generated elsewhere in order to assess the acceptability of a compound. The purpose of the symposium was to examine the circumstances under which extrapolation from one environment to another is valid on the basis of data generated under comparable conditions. It also considered ways in which relatively simple methods can be used to verify the field applicability of data obtained under sophisticated experimental conditions. 