日本各地の大気浮遊粒子状物質の多元素分析 (III)

抄録

Results of multielement analyses of airborne particulate samples collected at various residential areas in Japan were examined from the view point of characterizing the elemental air pollution, and it was attempted to find out measures which make it possible to grasp simply and clearly the features of elemental pollution. Measured elemental concentrations showed in general a log-normal distribution, and the geometric standard deviation, σ_g, is quite different from element to element. Geometric deviation, d_g (d_g=log (C/C)/log σ_g, where C and C are measured concentration and geometric mean concentration, respectively) and accumulation frequency were calculated for each element, and their usefulness in characterizing the elemental air pollution was evaluated.
Geometric deviation (or accumulation frequency) is considered to be a useful measure for grasping the features of elemental air pollution, because geometric deviation not only indicates the orientation of a measured concentration relative to the geometric mean concentration, but also decides the ranking of the measured concentration among all the measured concentrations.
For the purpose of comparing many measured concentrations of various elements with one another, geometric deviation is more convenient than “reference concentration”, which was introduced in Report I, especially because geometric deviation allows comparison of measured concentrations with one another regardless of element.