Exploration of Oxidative Stress and Inflammatory Markers in Relation to Urinary Phthalate Metabolites: NHANES 1999-2006

Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, Michigan 48109-2029, United States.
Environmental Science & Technology (Impact Factor: 5.33). 11/2011; 46(1):477-85. DOI: 10.1021/es202340b
Source: PubMed


Phthalate exposure has been associated with a wide range of adverse health outcomes in limited epidemiologic studies, and inflammation and oxidative stress have been hypothesized as potential mechanisms involved. In the present study we investigated associations between urinary concentrations of phthalate metabolites and potential blood markers of oxidative stress (bilirubin) and inflammation (alkaline phosphatase [ALP], absolute neutrophil count [ANC], ferritin [adjusted for iron status], and fibrinogen), using data from 10,026 participants in the National Health and Nutrition Examination Survey (NHANES) recruited between 1999 and 2006. After adjustment for covariates we found that bilirubin was inversely associated with several phthalate metabolites (all p-values <0.0001), including the metabolites of di-2-ethylhexyl phthalate (DEHP) and dibutyl phthalate (DBP), in addition to monobenzyl phthalate (MBzP) and mono-(3-carboxypropyl) phthalate (MCPP). Since bilirubin is a potent antioxidant these relationships suggest that phthalates may be associated with increased oxidative stress. Many of the same metabolites were also significantly and positively related with ANC, ALP, and ferritin, suggesting phthalates may be associated with increased inflammation. These markers may be useful in other studies of low-dose exposure to environmental contaminants.

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    • "NHANES is an ongoing cross-sectional study designed to measure subject exposure to various environmental chemicals, dietary intake patterns, and various health outcomes [69]. Our previous studies indicated several associations between urinary phthalate metabolites and serum markers of oxidative stress in a large human population [70,71]. As a follow-up, this analysis examines the same association when phthalate exposure occurs in conjunction with exposure to other environmental contaminants that may also be capable of causing an oxidative stress response. "
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