Comparative Screening Analytic Methods for Elderly of Blood Methylmercury Concentration between Two Analytical Institutions

Methylmercury is widely known to be a toxic substance in the human, especially a nervous system. However, it is difcult to accurately measure the amount of methylmercury in blood, and the form of methylmercury is variously presented. Te purpose of study was to compare the total mercury and methylmercury measurements techniques and detection levels between analytical institutions in two countries using the same elderly human blood samples. Total mercury using gold amalgamation direct mercury analysis method (both) and methylmercury using the dithizone extraction and gas chromatography-electron capture detector (GCECD) method (N Lab in Japan) and the cold vapor atomic fuorescence spectrophotometer (CVAFS) method (D Lab in Korea) were measured in 47 subjects who agreed to participate in this study. Total mercury concentrations in both analytical laboratories were observed at similar levels (9.4 versus 9.5 ug/kg, p=0.898) and the distribution was highly correlated. However, the concentration of methylmercury showed some diference between two laboratories (9.1 versus 8.6 ug/kg, p<0.001). Due to diferent recovery rates by diferent analytical methods, it is assumed that the methyl/total mercury ratio in N lab in Japan was higher than D lab in Korea (96.8 versus 90.4%, p<0.001). Te GC-ECD was more sensitive method than CVAFS in methylmercury analytic techniques.