Urine Arsenic and Arsenic Metabolites in U.S. Adults and Biomarkers of Inflammation, Oxidative Stress, and Endothelial Dysfunction: A Cross-Sectional Study

BACKGROUND: Arsenic (As) exposure has been associated with increased risk for cardiovascular disease (CVD) and with biomarkers of potential CVD risk and inflammatory processes. However, few studies have evaluated the effects of As on such biomarkers in U.S. populations, which are typically exposed to low to moderate As concentrations. OBJECTIVES: We investigated associations between As exposures and biomarkers relevant to inflammation, oxidative stress, and CVD risk in a subset of participants from the New Hampshire Health Study, a population with low to moderate As exposure ([Formula: see text]). METHODS: Associations between toenail As, total urine As (uAs), and %uAs metabolites [monomethyl ([Formula: see text]), dimethyl ([Formula: see text]), and inorganic (%iAs) species] and plasma biomarkers, including soluble plasma vascular and cellular adhesion molecules (VCAM-1 and ICAM-1, respectively), matrix metalloproteinase-9 (MMP-9), tumor necrosis [Formula: see text] , plasminogen activator inhibitor-1 (PAI-1), and urinary oxidative stress marker [Formula: see text] ([Formula: see text]), were evaluated using linear regression models. RESULTS: Covariate-adjusted estimates of associations with a doubling of urinary As suggested an 8.8% increase in [Formula: see text] (95% CI: 3.2, 14.7), and a doubling of toenail As was associated with a 1.7% increase in VCAM-1 (95% CI: 0.2, 3.2). Additionally, a 5% increase in %uMMA was associated with a 7.9% increase in [Formula: see text] (95% CI: 2.1, 14.1), and a 5% increase in %uDMA was associated with a 2.98% decrease in [Formula: see text] [(95% CI: [Formula: see text] , 0.21); [Formula: see text]]. However, in contrast with expectations, a doubling of toenail As was associated with a 2.3% decrease (95% CI: [Formula: see text] , [Formula: see text]) in MMP-9, and a 5% increase in %uMMA was associated with a 7.7% decrease (95% CI: [Formula: see text] , [Formula: see text]) in PAI-1. CONCLUSION: In a cross-sectional study of U.S. adults, we observed some positive associations of uAs and toenail As concentrations with biomarkers potentially relevant to CVD pathogenesis and inflammation, and evidence of a higher capacity to metabolize inorganic As was negatively associated with a marker of oxidative stress. https://doi.org/10.1289/EHP2062