干旱区生态环境知识资源中心

Expansion in population, industrial activity and the requirement for better health, have resulted in an increasing need to quantify levels of natural radioactivity in potable waters and the surface environment. This is particularly so in the semi-arid terrains of Africa and the Middle East, where exposure to environmental radioactivity is potentially increasing through changes in groundwater exploitation, land-use and building practice.

This paper describes the results of a three-year collaborative study into the distribution of natural series radionuclides (U, Th, Ra-226 and Rn-222) and associated potentially toxic elements (Se and Mo) in post-Cretaceous sediments and associated groundwaters from Cyprus and Jordan. Data are presented from: (a) regional baseline studies, which include the determination of radionuclides and other potentially harmful trace elements in groundwater samples, soils and soil gas, (b) an assessment of the geochemical origin and mobility of these elements and (c) an assessment of the potential hazard resulting from the presence of elevated concentrations of these elements.

Results emphasise the need for integrated baseline studies in hazard assessment and indicate that the presence and remobilisation of naturally occurring radionuclides within the southern Mediterranean basin result in significant excess exposure to the general population.