Human Biomonitoring of Acrylamide in Chinese Population: New Daily Exposure and Risk Assessment Linking Dietary Food Intake with Internal Urinary Metabolite Exposure

Acrylamide (AA), a probable class 2A carcinogen, is a typical daily exposure contaminant widely existing in both the environment and various thermally processed foods. Despite over 20 years since the discovery of AA, the holistic risk assessment outcomes based on internal and external exposure associations are still poorly understood. Here we used urinary mercapturic acid biomarkers of AA intake to indicate the short-term exposure to AA for human biomonitoring and conducted the risk assessment in a population aged 45-75 years in Jinhua, China (n = 1638). This assessment was analyzed and evaluated based on daily dietary intake data and data on internal exposure levels of AA in urine. The estimated daily intake of AA based on the food frequency questionnaire (EDI_FFQ) for both male and female participants was 0.16 μg AA kg^-1 day^-1. Dietary intake exposure levels were also extrapolated from urine exposure levels using our previously constructed physiologically based toxicokinetic (PBTK) model for AA. The results showed that males (0.15-0.35 μg AA kg^-1day^-1) had slightly higher estimated daily intake values than females (0.12-0.31 μg AA kg^-1 day^-1) calculated from the internal exposure levels of AA adjusted by creatinine, which was consistent with the predictive results of the physiologically based toxicokinetics model. The mean creatinine-adjusted margins of exposure (MOE_Cre) values for male and female were 1158 and 1456, respectively, while the MOE_Cre values for male and female at the P95 distribution level were 486 and 547, respectively. The results suggested that the present short-term exposure to AA may exhibit a noncarcinogenic but toxicological effect on highly exposed participants in Chinese population, though the current population-based exposure to AA remained overall at lower levels compared with those in other countries and regions. Furthermore, due to the prevalence of the exposed population, rigorous screening and follow-up monitoring of AA exposure is required to keep AA exposure within the limits of no harmful health consequences.