Biomonitoring of organophosphate triesters and diesters in human blood in Jiangsu Province, eastern China: Occurrences, associations, and suspect screening of novel metabolites

Since organophosphate (OP) triesters are ubiquitous in environmental matrices, there is an increasing concern regarding human exposure to OP triesters or their metabolites. In this study, we measured levels of 16 OP triesters and 4 OP diesters in n = 99 human blood samples of non-occupationally exposed adults (aged 18–87) from Jiangsu Province, eastern China. Based on the measured concentrations, statistical difference and correlativity were calculated to characterize the population diversity and potential sources of OP triester and diester. Di (2-ethylhexyl) phosphate (DEHP) and 2-ethylhexyl diphenyl phosphate (EHDPP) were found in many participants' blood, with median concentrations of 1.2 (range: n.d. – 44.7, detection frequency: 99%) and 0.85 (n.d. – 28.8, 68%) ng mL−1, respectively. Blood samples of older participants contained significantly lower concentrations of OP diesters or triesters than their younger counterparts (p