Mercury Exposure, DNA Methylation, and Cardiometabolic RiskAbstract Number:1833 Jaclyn M. Goodrich*, Niladri Basu, Alfred Franzblau, Joseph Kochmanski, Anna Sadovnikova, Hwai-Nan Chou, and Dana C. Dolinoy Jaclyn M. Goodrich* University of Michigan School of Public Health, United States, E-mail Address: [email protected] Search for more papers by this author , Niladri Basu McGill University, Canada, E-mail Address: [email protected] Search for more papers by this author , Alfred Franzblau University of Michigan School of Public Health, United States, E-mail Address: [email protected] Search for more papers by this author , Joseph Kochmanski University of Michigan School of Public Health, United States, E-mail Address: [email protected] Search for more papers by this author , Anna Sadovnikova University of Michigan School of Public Health, United States, E-mail Address: [email protected] Search for more papers by this author , Hwai-Nan Chou American Dental Association, United States, E-mail Address: [email protected] Search for more papers by this author , and Dana C. Dolinoy University of Michigan School of Public Health, United States, E-mail Address: [email protected] Search for more papers by this author AbstractEvidence suggests mercury (Hg) exposure influences DNA methylation and risk for cardiovascular and metabolic disorders. This study hypothesizes that methylmercury (MeHg, from fish consumption) and inorganic Hg (I-Hg, from dental amalgam) will be associated with differential DNA methylation at candidate regions and will influence cardiometabolic risk factors. Dental professionals with occupational and environmental exposures to I-Hg and MeHg, respectively, were recruited at a meeting of the American Dental Association (ADA, n=443). Information on I-Hg and MeHg exposure sources, health history, and demographics was collected via questionnaire. Total Hg was quantified in biomarkers of MeHg (geometric mean (95% CI): hair 0.60 (0.55-0.67) µg/g; blood 3.68 (3.39-3.99) µg/L) and I-Hg (urine 1.31 (1.20-1.42) µg/L). Hg intake estimated from reported fish consumption predicted hair and blood Hg levels. Personal amalgams, amalgams handled occupationally, and working hours predicted urine Hg levels. DNA methylation was quantified using bisulfite converted DNA isolated from blood leukocytes (n=410) and saliva (n=209) via pyrosequencing at long interspersed nuclear elements (LINE-1) and selenoprotein p1 (SEPP1). The SEPP1 promoter was hypomethylated (by average 18%) in saliva DNA compared with blood leukocyte DNA from the same individuals. Each log-unit of urine Hg was associated with a 1.3% increase in SEPP1 methylation in blood leukocytes in linear regression adjusting for sex, age, race, white blood cell count, and urinary specific gravity. Indicators of cardiometabolic health (e.g., blood pressure, cholesterol profile, and glycated hemoglobin) were measured. Preliminary results indicate that hair and blood Hg are associated with increased glycated hemoglobin after adjusting for covariates (p<0.05). To improve risk assessment of MeHg and I-Hg, additional work characterizing Hg’s impact on the epigenome and early indicators of cardiometabolic disease is warranted.