Modeling the Effects of Dietary Arsenic and Nutrient Intake on Urinary Arsenic Biomarkers

Persistent Link:
http://hdl.handle.net/10150/223339
Title:
Modeling the Effects of Dietary Arsenic and Nutrient Intake on Urinary Arsenic Biomarkers
Author:
Kurzius-Spencer, Margaret
Issue Date:
2012
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Embargo:
Release after 18-Oct-2012
Abstract:
Background: Arsenic (As) is a naturally-occurring element with known toxicant effects. The primary exposure pathway is through ingestion, but the overall contribution of food versus water and the impact of specific dietary nutrients on urinary As excretion is not well understood. Methods: Secondary analyses of laboratory results from food, water and urine samples, questionnaire and anthropometric data, and dietary records were performed on four study populations: the National Health Exposure Assessment Survey (NHEXAS)-Arizona, Arizona Border Survey (ABS), the Arizona sub-group of the Binational Arsenic Exposure Survey (BAsES), and the 2003-2004 National Health and Nutrition Examination Survey (NHANES). Dietary As intake was measured in duplicate food samples and/or modeled from dietary records for each population using the U.S. Total Diet Study (TDS) arsenic residue database and a published market basket survey. Urinary total As, As⁵, As³, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were analyzed, and sum of species As was calculated as the sum of As⁵, As³, MMA and DMA. Regression analyses modeled the relation between urinary As biomarkers (total, sum of species, MMA:sum of species, and DMA:MMA) and dietary As, adjusted for drinking and cooking water As intake, current smoking, sex, age, ethnicity, body mass index, and nutrient intake. Results: Modeled dietary As based on TDS mean As residue data greatly underestimated exposure as compared with measured As in duplicate diet samples and estimates based on other residue data. Dietary As was a significant predictor of urinary total As in all four populations, of sum of species As in both BAsES and NHANES, and of %MMA and DMA:MMA in NHANES. Dietary protein intake was associated with decreased sum of species As in both BAsES and NHANES, but dietary folate was not. Conclusions: Dietary As contributes a markedly greater proportion of total ingested As and is a better predictor of urinary As than water As intake in the U.S. Among subjects who did not consume seafood, total As exposure from food and water exceeded the provisional tolerable daily intake of 2.1 µg/kg body weight/day in 3-15% of these study populations. Increased protein intake may mitigate the effects of As.
Type:
text; Electronic Dissertation
Keywords:
human exposure; nutrients; urine; water; Epidemiology; arsenic; dietary
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Graduate College; Epidemiology
Degree Grantor:
University of Arizona

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleModeling the Effects of Dietary Arsenic and Nutrient Intake on Urinary Arsenic Biomarkersen_US
dc.creatorKurzius-Spencer, Margareten_US
dc.contributor.authorKurzius-Spencer, Margareten_US
dc.date.issued2012en
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.releaseRelease after 18-Oct-2012en_US
dc.description.abstractBackground: Arsenic (As) is a naturally-occurring element with known toxicant effects. The primary exposure pathway is through ingestion, but the overall contribution of food versus water and the impact of specific dietary nutrients on urinary As excretion is not well understood. Methods: Secondary analyses of laboratory results from food, water and urine samples, questionnaire and anthropometric data, and dietary records were performed on four study populations: the National Health Exposure Assessment Survey (NHEXAS)-Arizona, Arizona Border Survey (ABS), the Arizona sub-group of the Binational Arsenic Exposure Survey (BAsES), and the 2003-2004 National Health and Nutrition Examination Survey (NHANES). Dietary As intake was measured in duplicate food samples and/or modeled from dietary records for each population using the U.S. Total Diet Study (TDS) arsenic residue database and a published market basket survey. Urinary total As, As⁵, As³, monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA) were analyzed, and sum of species As was calculated as the sum of As⁵, As³, MMA and DMA. Regression analyses modeled the relation between urinary As biomarkers (total, sum of species, MMA:sum of species, and DMA:MMA) and dietary As, adjusted for drinking and cooking water As intake, current smoking, sex, age, ethnicity, body mass index, and nutrient intake. Results: Modeled dietary As based on TDS mean As residue data greatly underestimated exposure as compared with measured As in duplicate diet samples and estimates based on other residue data. Dietary As was a significant predictor of urinary total As in all four populations, of sum of species As in both BAsES and NHANES, and of %MMA and DMA:MMA in NHANES. Dietary protein intake was associated with decreased sum of species As in both BAsES and NHANES, but dietary folate was not. Conclusions: Dietary As contributes a markedly greater proportion of total ingested As and is a better predictor of urinary As than water As intake in the U.S. Among subjects who did not consume seafood, total As exposure from food and water exceeded the provisional tolerable daily intake of 2.1 µg/kg body weight/day in 3-15% of these study populations. Increased protein intake may mitigate the effects of As.en_US
dc.typetexten_US
dc.typeElectronic Dissertationen_US
dc.subjecthuman exposureen_US
dc.subjectnutrientsen_US
dc.subjecturineen_US
dc.subjectwateren_US
dc.subjectEpidemiologyen_US
dc.subjectarsenicen_US
dc.subjectdietaryen_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.disciplineEpidemiologyen_US
thesis.degree.grantorUniversity of Arizonaen_US
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