Changes in serum thioredoxin among individuals chronically exposed to arsenic in drinking water

► Three regions are selected as the areas affected by endemic arsenicosis of China. ► We first examine changes in serum TRX1 among individuals exposed to arsenic. ► A positive correlation was seen between serum TRX1 and total water arsenic intake. ► The same relationship was seen between serum TRX1 and urinary arsenic species. ► TRX as early biomarker of arsenicosis can be detected before skin lesions occur.