Health & Environmental Research Online (HERO)

Print Feedback Export to File
Journal Article 
Urinary phthalate metabolites and biomarkers of oxidative stress in pregnant women: A repeated measures analysis 
Ferguson, KK; Mcelrath, TF; Chen, YH; Mukherjee, B; Meeker, JD 
Environmental Health Perspectives
ISSN: 0091-6765
EISSN: 1552-9924 
BACKGROUND: Phthalate exposure occurs readily in the environment and has been associated with an array of health endpoints, including adverse birth outcomes. Some of these may be mediated by oxidative stress, a proposed mechanism for phthalate action.

OBJECTIVES: In the present study we explore the associations between phthalate metabolites and biomarkers of oxidative stress measured in urine samples from multiple time points during pregnancy.

METHODS: Women were participants in a nested case-control study of preterm birth (N=130 cases, N=352 controls). Each was recruited early in pregnancy and followed until delivery, providing urine samples at up to 4 visits. Nine phthalate metabolites were measured to assess exposure, and 8-hydroxydeoxyguanosine and 8-isoprostane were also measured in urine as markers of oxidative stress. Associations were assessed using linear mixed models to account for intra-individual correlation, with inverse selection probability weightings based on case status to allow for greater generalizability.

RESULTS: Interquartile range increases in phthalate metabolites were associated with significantly higher concentrations of both biomarkers. Estimated differences were greater in association with mono-benzyl phthalate (MBzP), mono-n-butyl phthalate (MBP), and mono-iso-butyl phthalate (MiBP), compared with di-2-ethylhexyl (DEHP) metabolites.

CONCLUSIONS: Urinary phthalate metabolites were associated with increased oxidative stress biomarkers in our study population of pregnant women. These relationships may be particularly relevant to the study of birth outcomes linked to phthalate exposure. Although replication is necessary in other populations, these results may also be of great importance for a range of other health outcomes associated with phthalates. 
Environment Abstracts; Health & Safety Science Abstracts; Toxicology Abstracts; Oxidative stress; Phthalic acid; biomarkers; Population studies; Phthalates; Pregnancy; Metabolites; 8-Hydroxydeoxyguanosine; Replication; Bioindicators; Internet; Females; ENA 02:Toxicology & Environmental Safety; X 24350:Industrial Chemicals; H 12000:Epidemiology and Public Health 
• Dibutyl Phthalate (DBP)
     Database Searches
          LitSearch Jul 2016 - Jan 2017
               Considered new
• Diisobutyl Phthalate (DIBP) Final
     Database Searches
          June 2015 Update
               Web of Science
               New for this Search
          December 2015 Update
               Web of Science
          June 2016 Update
               Web of Science
          January 2017 Update
     Primary Source of Health Effects Studies
          Human health effects studies
     Studies with Supporting Data
          Mechanistic and genotoxicity studies
• Phthalates – Targeted Search for Epidemiological Studies
     Source – all searches
     Source – Dec 2014 Update (Private)
     Source – Mar 2015 Update (Private)
     Source – Dec 2015 Update (Private)
     Source - Jun 2016 Update (Private)