Factors affecting urinary arsenic methylated metabolites in population exposed to elevated arsenic through drinking water / 中华地方病学杂志

ABSTRACT

Objective To explore the factors affecting urinary arsenic methylated metabolites in population exposed to elevated arsenic through drinking water.Methods Residents,including 73 males and 72 females,in a endemic village located in Inner Mongolia Autonomous Region where the concentration of arsenic in drinking water was 0.167 mg/L,were included in the study; moming urine samples were collected; individual height and weight were measured which could be used to calculate body mass index(BM庆) ; and smoking and drinking habit was investigated by a questionnaire survey.Urinary concentrations of inorganic arsenic (iAs),monomethylarsenic acid(MMA) and dimethylarsenic acid(DMA) were determined using high performance liquid chromatography hydride generation atomic fluorescence spectrometry (HPLC-HG-AFC).Total arsenic (T-As) level was calculated by the sum of iAs,MMA and DMA; iAs％,MMA％ and DMA％ was calculated based on iAs/T-As,MMA/T-As and DMA/T-As.One methylation ratio(PMI) and dimethyl rate(SMI) were calculated by MMA/iAs and DMA/MMA.Results SMI level of female was significantly higher than that of male [median (M) =4.18,3.38,x2 =11.219,P ＜ 0.05] ; MMA％ of female was significantly lower than that of male(M =15.1 9,18.06,x2 =9.272,P ＜ 0.05) ; DMA％ of female was significantly higher than that of male (M =65.61,59.47,x2 =11.728,P ＜ 0.05).Various forms of arsenic indexes were not affected by smoking,alcohol consumption and BMI(P ＞ 0.05).BMI was negatively correlated with MMA％,with correlation coefficient (r)-0.17 (P ＜ 0.05).Conclusions Under the same condition of arsenic exposure,arsenic methylation capacity of women is higher than that of men.Lower BMI is significantly associated with higher methylation capability of arsenic,but this correlation may be affected by other confounding factors.