Objective   To study the main organic pollutants in tap water and their genotoxicity in Kunming city.

  Methods   One hundred and fifty liters tap water sample were collected from three water works(A, B, C)and a control group(D).The organic pollutants in tap water were extracted by XAD-2 resin, then washed by methanol and acetone.The organic extractions were detected by using Gas Chromatography/Mass Spectrometry(GC/MS); Mouse micronucleus test(MT)was used to detect the genotoxicity effect of organic pollutants in vivo.

  Results   Total 335 organic pollutants were monitored under a certain condition in the above-mentioned water samples, including up to ten kinds of Environmental Protection Agency (EPA)priory pollutants and up to 20 kinds of mutagens and carcinogens.The micronucleus test results demonstrated that organic extraction from waterworks A could induce increasing micronucleus frequency and did not show dose response relationship.Organic extraction from waterworks B and C could notinduce increasing micronucleus frequency and did not show dose response relationship.The micronucleus test results of control sample were negative, too.

  Conclusion   The combination of GC/MS and micronucleus testis a rapid and effective method for evaluating organic pollutants in tap water.