基准剂量在镉接触环境流行病学研究中的应用

Application of Benchmark Dose(BMD)in an Epidemiological Study on a General Population Environmental-ly Exposed to Cadmium

[目的]通过环境流行病学研究 ,估测环境镉接触引起肾功能不全的基准剂量。[方法]镉污染区居住的居民为接触组 ,非污染区居民为对照组。尿镉 (UCd)为接触生物标记物 ;β 微球蛋白(UBM)、尿N_乙酰_β_D_氨基葡萄糖苷酶(UNAG)、尿视黄醇结合蛋白 (URBP)和尿白蛋白 (UALB)为效应生物标记物 ,并均用尿肌酐校正。[结果]长期接触镉可引起肾脏的损害。本次调查β2 微球蛋白、视黄醇结合蛋白、尿NAG酶和尿白蛋白重污染区显著高于对照区 ,与尿镉的增长呈明显的剂量效应关系。计算得基准剂量 (BMD) ,推出基准剂量的95 %低限水平 (LBMD)。镉所引起的各肾脏损伤指标的LBMD值是不同的 ,大小依次为尿NAG同功酶B(NAG_B)、NAG、UBM和UALB。[结论]镉引起的肾小球损害晚于肾小管损害;而NAGB的基准剂量值最低 。

The epidemiological studywas aimed to estimate the benchmarkdose for renal dysfunction caused by cadmiˉum exposure in a Chinese general population.The inhabitants living in both cadmium polluted and non_polluted areas were asked to participate in this study.Urinary cadmium(UCd)was used as exposure biomarker and urinaryβ 2 microgloburin,retional bindˉing protein(RBP),NAG and albumin were as effect biomarkers.All urine parameters were standardized to concentration of creatinine in urine.Renal dysfunction would appear after long termexposure to cadmium.In this study,it has been shown that urinaryβ 2 microgloburin,retional binding protein(RBP),NAG and albumin were higher in the population living in the area heavily polluted by cadmium than those in the non_pollutd area.There was a significant dose response relationship between exposure dose(urinary cadmiˉum)and the prevalence of hyper_β 2 microgloburinuria,RBPuria,NAGuria and albuminuria.BMDs were calculated using SPSS program and LBMDs also determined.The lowerlimitofBMD(LBMD)forUALBis the highestamongall.[Conclusion]Itindicates thatglumeroˉlar damage is later than tubular damage in renal damage related to cadmiumexposure.The LBMD for UNAGB is the lowest and would be a relevant sensitive biomarker for renal dysfunction caused by cadmium exposure.