Elevated autoimmunity in residents living near abandoned uranium mine sites on the Navajo Nation

Abstract

Specific autoantibodies were assessed among residents of the Navajo Nation in New Mexico chronically exposed to metal mixtures from uranium mine wastes and in drinking water supplies. Age and the extent of exposure to legacy waste from 100 abandoned uranium mine and mill sites were associated with antibodies to denatured DNA, previously known to be an early indicator of medication-induced autoimmunity. Surprisingly, autoantibodies to native DNA and/or chromatin were also linked to environmental exposure, specifically uranium consumption through drinking water for both men and women, while urinary arsenic was negatively associated with these autoantibodies in women. These findings suggest that contaminants derived from uranium mine waste enhanced development of autoantibodies in some individuals, while arsenic may be globally immunosuppressive with gender-specific effects. Specific autoantibodies may be a sensitive indicator of immune perturbation by environmental toxicants, an adverse effect not considered in current drinking water standards or regulatory risk assessment evaluations.

Minimal uranium immunotoxicity following a 60-day drinking water exposure to uranyl acetate in male and female C57BL/6J mice

“…Exposure to elevated levels of U was found to be associated with increased incidence of systemic lupus erythematosus in a cohort of individuals living near a U processing plant (Lu-Fritts et al, 2014). Recent findings from Erdei et al, (2019), indicate elevation of serological autoantibodies in Native Americans living in close proximity to abandoned uranium mine wastes sites. Additionally, individuals living near abandoned U mine sites had decreased NK and T-cell counts in peripheral blood (Lourenço et al, 2013).…”

“…Many of these rural communities rely on unregulated drinking water sources (i.e., well water) that exceed the United States Environmental Protection Agency and World Health Organization maximum contaminant level for U of 30 ppb (US EPA 2006;WHO 2012;deLemos et al, 2009;Hoover et al, 2017). As a result, many people in this region are chronically exposed to U at levels that have been linked to a multitude of detrimental health outcomes, including immune dysfunction (Lu-Fritts et al, 2014;Lourenço et al, 2013;and Erdei et al, 2019). In particular, data from Native American populations living in close proximity to abandoned mine waste sites indicate a correlation between uranium and other metal exposures and the presence of serological indicators of autoimmunity (i.e., increased prevalence of anti-nuclear antibodies) (Erdei et al, 2019;Ong et al, 2014).…”

Urinary Metals Concentrations and Biomarkers of Autoimmunity among Navajo and Nicaraguan Men

“…Specific autoantibodies were also detected by enzyme-linked immunosorbent assay (ELISA) using an in-house procedure, as previously described [ 55 , 56 ], and used by members of our team in Navajo Nation studies [ 34 ]. Antibody binding to chromatin, histones, denatured DNA (dDNA or single-stranded DNA), and native DNA (nDNA or double-stranded DNA) was quantified in duplicate serum samples in a 1:200 dilution after incubation in antigen-coated wells for 2 h at room temperature [ 55 , 56 ].…”

“…While, the exposure to mercury from fish consumption and residential proximity to an arsenic-contaminated site have been associated with increased prevalence of antinuclear antibodies (ANA). Specific autoantibodies [33] in a Sioux community, and elevated autoantibodies, are associated with living near uranium mines in Navajo Nation residents [34]. There are no studies so far that have assessed the relationship of in vivo biomarkers of autoimmunity with a comprehensive panel of metals yet.…”

Assessment of particulate matter toxicity and physicochemistry at the Claim 28 uranium mine site in Blue Gap, AZ

“…The history of AUMs and their impact on the people and land of the Navajo is a long and complicated true-crime story (Pasternak, 2011). From an academic perspective, the "legacy" of AUMs is an extensive list of health adversities including kidney disease, cardiovascular disease, increased cancer mortality, and hypertension (Blake et al, 2015;Dashner-Titus et al, 2018;Dawson & Madsen, 2011;Erdei et al, 2019;Jones, 2014;Lewis et al, 2017;Zychowski et al, 2018). Although lung cancer and respiratory disease prevalence appears to be higher in miners who smoke cigarettes, researchers found both smokers and nonsmokers had statistically elevated rates of respiratory disease (Dawson & Madsen, 2011).…”