燃煤型砷中毒病区人群与非病区人群砷甲基化代谢水平的比较

目的 描述燃煤型砷中毒病区人群与非病区人群砷甲基化代谢的特征,比较两区人群砷甲基化代谢水平的差异.方法 于2005年12月随机抽取某燃煤型砷中毒病区常住居民228名(包括116名砷中毒确诊患者,内对照成人60名,14岁以下儿童52名),同时随机抽取非病区常住居民218名(外对照组成人149名,儿童69名),采集空腹晨尿,用离子色谱氢化物发生原子荧光法测定尿中无机砷(InAs)、一甲基胂酸(MMA)和二甲基胂酸(DMA).结果 燃煤型砷中毒病区人群砷的甲基化水平均显著低于非病区人群(P＜0.05),但病区病例组与内对照组之间未见显著差异.病区男性和女性砷的甲基化水平分别低于非病区男性和女性;病区男性对砷的甲基化能力低于女性,但非病区男性与女性之间比较,差异未见统计学意义.病区各年龄段人群砷的甲基化水平均低于非病区居民;随着年龄增加,MMA比例和MMA/InAs比值呈增加趋势,而DMA比例和DMA/MMA比值呈下降的趋势.结论 燃煤型砷中毒病区人群砷的甲基化水平低于非病区人群,男性和女性对砷的甲基化能力存在差异,砷甲基化代谢水平随着年龄增加呈下降趋势.

Comparison of Arsenic Methylating Metabolism between Population in Arsenic Endemic Area and in Control Area

Objective To investigate the characteristics of arsenic methylating metabolism in population in coal-burning type arsenism endemic area and in control area, and to explore the difference between the two population. Methods 228 residents, including 116 arsenism patients, in an arsenism endemic area, and 218 normal residents in a control area were voluntarily enrolled in this study. Urine samples were collected, urinary inorganic arsenic (InAs), monomethylarsenic acid (MMA) and dimethylarsenic acid (DMA) were determined using ion chromatogram combined with HG-AFS. Results The methylation level of residents in endemic area was lower than that in control area, but no difference was observed between the case group and control group in endemic area. The methylation level of male and female in endemic area was respectively lower than male and female in control area. In endemic area, the methylation level of male was lower than female, but no difference in gender was observed in the control area. In each age group, the methylation level of residents in endemic area was lower than that in the control area. MMA proportion and MMA/InAs ratio showed an increasing tendency, while DMA proportion and DMA/MMA ratio showed a decreasing tendency with the increase of age. Conclusion Arsenic methylation level in coal-burning type arsenism endemic area is lower than that in control area. Male and femal people have different arsenic methylation capacity, and the methylation level showes a decreasing tendency with the increase of age.