Abstract: The chromosomal aberrations and sister chromatid exchanges of the peripheral lymphocytes from the workers in different polluted environments were observed,and the results are as follows:1.Average frequencies of the cells with chromosomal aberrations and reakages were 2.47% and 2.53% for pit workers respectively,3.22% and 3.29% for smelters,1.00% and 1.10% for up-pit workers,and 0.4% and 0.5% for non-exposed workers.2.Average frequencies of SCEs were 4.25±0.13 for pit workers,3.49±0.10 for up-pit workers,3.26±0.09 for smelters,and 2.46±0.09 for non-exposed workers.3.In three groupes with different urine arsenic level,average frequencies of SCEs were 5.35±0.31,5.76±0.24,and 5.60±0.19,respectively,and average frequencies of chromosomal aberrations and breakages were 1.75%,2.16%,1.90% and 1.75%,2.16%,2.00%,compared with 0.6% for each control group.4.In four groups with different urine lead,average frequencies of SCEs were 5.07±0.1,5.82±0.21,and 5.96±0.09 respectively,and average frequencies of the cells with chrosomal aberrations and breakages were 2.53%,2.18%,2.59%,2.42% and 2.58%,2.36%,2.42% and 2.66%,compared with 0.6% for each control group.The difference between the exposed groups and each control groups are statistically significant.