[en] The annual report of the Environmental and Medical Sciences Division is primarily concerned with research and analytical services, covering both radiological and non-nuclear research programmes in the environmental and toxicological fields. Environmental safety projects from the Hazardous Materials Service, the Waste Research Unit, the Chemical Emergency Centre, the Waste Management Information Bureau, the Landfill Research Project and the Operations and Disposals Team are described. The work of the Environmental Analytical Services is also outlined. The Atmospheric Pollution Programme has been mainly concerned with the life cycle of sulphur compounds in the atmosphere and with the effects of pollutants, mainly hydrocarbons, on the level of ozone in the stratosphere. The Aerosols and Metabolic Studies Programme included further studies on the environmental behaviour and the metabolism of inhaled lead from vehicle exhausts and whole-body counting of plutonium. Inhalation Toxicology and Radionuclide Analysis studies included the deposition and clearance of inhaled particles and the effects of radioactive (²³⁹Pu) and non-radioactive dusts on the lung. A substantial amount of research was performed in the field of radiation physics, in relation to dosimetry, applied radiation spectrometry, data systems, radioactive fallout and environmental analysis. (UK)