[Levels and distribution of 15 rare earth elements in tumor and normal lung tissue from the patients with lung cancer].

Ten tumor tissue and normal tissue around tumors were collected from the patients with lung cancer. After digested by mixed acids(HNO3:HClO4 = 10:1), 15 rare-earth elements (REEs) in the tissue were measured directly by ELAN 5000 ICP-MS. Tissue levels and distribution of 15 REEs were analyzed and compared with those in healthy human lung tissue measured in the same condition. Re (rhenium) was used as an internal standard element to compensate for matrit inhibition and sensitivity drift. Recoveries of standard addition for REEs was 92.9%-111.3% and the precision was 0.96%-3.07%. Results showed that levels of 15 REEs in normal tissues around the tumor was as 2.07-2.51 times high as those in the tumor tissue, while the REE distribution curves of them was similar. There were positive abnormalities of Ce and negative abnormalities of Eu in REE curves of both tissue after chondrite-normalized. Compared REE level and distribution pattern in normal tissue with those in tumor tissue from patients with lung cancer, it was found that contents of light REE in lung tissue of health human were much higher while the contents of media and heavy REE were much lower. LREE/HREE in the tumor tissue and normal tissue with lung cancer and health human lung tissue were 12.99, 13.72 and 44.11 respectively. This study suggested that there might be light REEs accumulation in human lung tissue compared with REE distribution in the air particulates and soil. Light REEs accumulation in the lung of healthy people was more obviously than that in patients with lung cancer.