摘要:The toxicity of suspended particulate matter (SPM) in air by the simple protozan Tetrahymena test was investigated. It was shown that the growth of Tetrahymena was inhibited by water-soluble components extracted from SPM which were collected at industrial (A) and residential (B) areas. The degree of growth inhibition of Tetrahymena was not always proportional to the concentration of the pollutants and not affected by seasonal differrences in SPM regarding both areas. The SPM extract was fractionated by chromatography on a column of sephadex G-15, each fractions was tested cocerning its toxicities by the Tetrahymena culture method and it was shown that culture added low molecular weight fraction produced a smaller number cells than the other fractions. These low molecular weight fractions contained a number of nitrate ions, so the author wondered whether such ions were associated or not with the toxicity of extracts.