儿童稀土暴露的健康效应研究

目的　探讨稀土暴露与儿童健康的关系。方法　选择与稀土效应有关的生长发育水平、免疫功能以及智能发育作为儿童稀土暴露健康效应的指标。在江西省某稀土矿区和对照区对 7～ 10岁儿童进行生长发育有关指标测量。采用免疫消浊比色法、化学免疫发光法、流式细胞仪技术对儿童血清中IgA、IgG、IgM和补体C3、C4、IgE以及血中淋巴细胞亚群CD+3 、CD+4 、CD+8、CD+4 CD+8及NK细胞进行测定 ;采用绘人智能法对儿童进行智商测定 ;并采用ELAN - 5 0 0 0型号的电感藕合等离子体质谱仪对儿童进行血中稀土元素总量和分量测定 ,同时用简单回归、多元逐步回归等方法分析稀土暴露情况与儿童健康之间的关系。结果　儿童血样中 15种稀土元素均可检出 ,且稀土暴露区儿童血稀土总含量 (2 18± 1 0 8)ng g ,比对照组 (1 2 6± 0 35 )ng g高出 1 73倍 (P <0 0 1)。稀土暴露组儿童肺活量、血压较对照组低 ;稀土暴露区儿童体液免疫有所改变 ,稀土暴露组IgM比对照组显著降低 (P <0 0 5 ) ,儿童T淋巴细胞亚群测定结果显示 ,CD+3 、CD+8、CD+4 CD+8有明显改变 (P <0 0 5 ) ,稀土暴露组儿童血中CD+3 和CD+8比对照组CD+3 、CD+8明显降低 ,而CD+4 CD+8比值则有所升高。稀土暴露区儿童智商得分显著低于对照组儿童 ;高智能儿童比

Study on the effects of exposure to rare earth elements and health-responses in children aged 7-10 years

OBJECTIVE: To study the effects of environmental exposure to rare earth elements (REEs) on health in children. METHODS: The level of physical growth and development, function of immune system, intelligence were chosen as the health-response indexes of children. Indicators for physical growth and development were measured. IgA, IgG, IgM and complement C3, C4 in blood serum were determined with turbidimeter measure, IgE were determined by chemiluminescence immunoassay (CLIA), lymphocyle subset CD3, CD4, CD8, CD4/CD8 and NK were determined by flowcytometry. Intelligence quotient (IQ) were examined with Drawing A Man Test in the children aged 7-10 years randomly sampled in the area containing rare earth (RE) ore and the control area in Xunwucounty, Jiangxi. Blood REEs were determined by inductively coupled plasma source mass pectrometry (ICP-MS). RESULTS: All 15 kinds of REEs were detected in each sample, the quantity of blood REEs of the children were lower in exposure group than in control group and in the rare earth area (2.10 +/- 0.88)ng/g] was 1.73 times as that of the children in the control area (1.26 +/- 1.35) ng/g]. The difference is significant (P < 0.01). The humoral immunity would be changed in the body of the children exposed to REEs, the quantity of IgM was lower in exposure group than in control group. The measuring result of T lymph subgroup of the children indicates: CD3, CD4, CD4/CD8 changed a lot. The percent of CD3, CD8 were significantly lower and CD4/CD8 was significantly higher in exposure group than in control group. The score of IQ was lower significantly in the exposure group than in the control. The percentage of high IQ decreased, the percentage of low IQ increased. Multiple regression analysis showed the variable of blood REEs in exposure to REEs group or those in the control group were introduced into the Vital capacity, blood pressure and IgM regression model. The distance from home to the RE area and either RE put in home influenced the score of children's IQ. CONCLUSION: The children aged 7-10 years in RE ore area may have higher REEs burden in the body, and exposure to REEs could have adverse influences in children.