TitleMetal exposure and oxidative stress markers in pregnant Navajo Birth Cohort Study participants.
Publication TypeJournal Article
Year of Publication2018
AuthorsDashner-Titus EJ, Hoover J, Li L, Lee J-H, Du R, Liu KJian, Traber MG, Ho E, Lewis J, Hudson LG
JournalFree Radic Biol Med
Date Published2018 08 20

Contamination of soil and water by waste from abandoned uranium mines has led to chronic exposures to metal mixtures in Native American communities. Our previous work demonstrated that community exposures to mine waste increase the likelihood of developing cardiovascular disease, as well as the likelihood of developing multiple chronic diseases including diabetes, hypertension and kidney disease. Exposure to various environmental metals is associated with elevated oxidative stress, which is considered a contributor to these and other chronic disease states. The purpose of the current research was to assess potential associations between exposure to uranium and arsenic and evidence for increased oxidative stress as measured by urinary F -isoprostanes in pregnant women enrolled in the Navajo Birth Cohort Study. The current study also included an analysis of zinc as a potential mediator of oxidative stress in the study population. Urinary arsenic and uranium, serum zinc and urinary F -isoprostanes were measured for each study participant at enrollment. Study participants were pregnant women with median age of 26.8; 18.9% were enrolled in the 1st trimester, 44.7% were enrolled in the 2nd trimester, and 36.4% were enrolled in the 3 trimester. Median urinary metal levels were 5.5 and 0.016 µg/g creatinine for arsenic and uranium, respectively. Multivariable regression analysis indicated a significant association between arsenic exposure and the lipid peroxidation product 8-iso-prostaglandin F controlling for zinc and trimester. No associations were detected with uranium despite evidence that levels were in the Navajo Birth Cohort samples were 2.3 times the median reported for women in the National Health and Nutrition Examination Survey (2011-12). Zinc was not found to have any causal mediation of the effects of the other metals on oxidative stress. The current work is consistent with other studies that have detected an association between arsenic and elevated oxidative stress. In contrast to arsenic, uranium did not appear to increase oxidative stress response in this study population. These findings are relevant to assessing the potential human impact of chronic exposure to mixed metal waste from abandoned uranium mines.

Alternate JournalFree Radic. Biol. Med.
PubMed ID29723666
PubMed Central IDPMC6381929
Grant ListP50 ES026102 / ES / NIEHS NIH HHS / United States
P42 ES025589 / ES / NIEHS NIH HHS / United States
P30 CA118100 / CA / NCI NIH HHS / United States
U01 TS000135 / TS / ATSDR CDC HHS / United States
R01 ES021100 / ES / NIEHS NIH HHS / United States
R01 CA182969 / CA / NCI NIH HHS / United States
K12 GM088021 / GM / NIGMS NIH HHS / United States