Applications of radioisotopes to environmental pollution control

Radioisotope techniques are variously used for environmental pollution control. Current developments and trends in Japan in the analysis of environmental elements such as air and water are described as follows, analysis of sulfur content in fuel using RIs, ECD gas-chromatography, RI-excited energy dispersion type X-ray fluorescence analysis, and activation analysis. The RI sulfur meter is used increasingly because of its easy handling, fast operation and exactness, but also with some problems. ECD gas-chromatography is finding its application to photochemical smog. In X-ray fluorescence analysis, sealed radioisotopes are used in place of X-ray tubes. The instrumental activation analysis of atmospheric floating dust is highly effective. The activation analysis of polluted water is most desirable, but its pre-treatment is necessary to facilitate the irradiation. (Mori, K.)