Abstract: The micronucleus test with Vicia faba root tip cell was used to study the water pollution of Sanhai in Beijing with 21 and 22 samples respectively in 2003 and 2004.The results showed that the whole aquatic area was polluted and appeared genetic toxicity.The sample frequencies with micronucleus rates lower than 1.5 were 476% and 18.18%,respectively,which distributed in the center of Qianhai and Houhai.The samples of micronucleus rates between 15～20 were 28.57% and 13.64%.However,the samples of micronucleus rates between 2.0～3.5 were 28.57% and 45.45%.The samples which micronucleus rates were higher than 3.5 were 38.0% and 22.7%.Among these sample sites,the densely populated Xihai was heavily polluted.

Key words: Natural zeolite, Soil nutrient, Bioavailability, Soil chemical property