Investigation on liver function among population in high background of rare earth area in south China

The health effects of long-term ingestion of rare earth elements (REEs) on the villagers living in high-REE-background areas in South Jangxi Province, China were studied. Major health complaints from the REE area population included indigestion, diarrhea, abdominal distension, anorexia, weakness, and fatigue, especially after high-fat or high-protein intake. Liver function tests were conducted for adult villagers. Among them, 45 live in a heavy rare earth (HREE) area, 62 in a light rare earth (LREE) area, and 49 in the control area. Test results showed that serum total protein and globulin from both HREE and LREE areas, as well as albumin from the LREE area, were significantly lower (p<0.05-0.01) compared to the results from the control area, whereas albumin from the HREE area showed no significant variance (p>0.05). The chi-square test showed that Serum-glutamic pyruvic transaminase (SGPT) in both areas were not significant (p>0.05), whereas the IgM in the HREE area was significantly elevated. It is our conclusion that long-term ingestion of REE affected activities of some digestive enzymes, causing malabsorption and indigestion, and might further lead to a low-protein effect for the villagers in the LREE area. However, the damage to the liver was rather mild. The elevation of IgM was probably the result of stimulation induced by the formation of a large amount of granules as a result of direct binding of REEs to globulin or albumin (combination of REEs with globulin or albumin).