As in previous years this section of A n n u d Reports will review recent developments in radiochemistry, but exclude those aspects, such as radiation chemistry and actinide chemistry, where radioactivity is not of primary importance. Nuclear reactions leading to specific isotopes will be considered first, followed by a description of chemical reactions induced by recoil atoms and a selection of recent reports on the preparation of labelled molecules. In the final section the increasingly important role of radiochemical procedures in tackling environmental problems, both man-made and of natural origin, will be reviewed.The spate of international conferences on various aspects of radiochemistry continues unabated ; the 8th international conference on radiopharmaceutical chemistry,' the 4th international symposium on the synthesis and applications of isotopically labelled compounds,2 the 4th European symposium on radiopharmacy and radiophar-mace~ticals,~ and the 2nd international conference on methods and applications of radioanalytical ~h e m i s t r y , ~ as well as national meetings such as the 3rd general congress on nuclear energy held in Brazil.' Books on basic aspects of nuclear chemistry6,' on nuclear methods of analysis,8 and on the uses of isotopes in the physical and biomedical sciences' have also appeared. More specific papers have