Article

Polycarbonate bottle use and urinary bisphenol A concentrations.

Department of Epidemiology, Harvard School of Public Health, Harvard University, Cambridge, Massachusetts, USA.
Environmental Health Perspectives (Impact Factor: 7.26). 09/2009; 117(9):1368-72. DOI: 10.1289/ehp.0900604
Source: PubMed

ABSTRACT Bisphenol A (BPA) is a high-production-volume chemical commonly used in the manufacture of polycarbonate plastic. Low-level concentrations of BPA in animals and possibly in humans may cause endocrine disruption. Whether ingestion of food or beverages from polycarbonate containers increases BPA concentrations in humans has not been studied.
We examined the association between use of polycarbonate beverage containers and urinary BPA concentrations in humans.
We conducted a nonrandomized intervention of 77 Harvard College students to compare urinary BPA concentrations collected after a washout phase of 1 week to those taken after an intervention week during which most cold beverages were consumed from polycarbonate drinking bottles. Paired t-tests were used to assess the difference in urinary BPA concentrations before and after polycarbonate bottle use.
The geometric mean urinary BPA concentration at the end of the washout phase was 1.2 microg/g creatinine, increasing to 2.0 microg/g creatinine after 1 week of polycarbonate bottle use. Urinary BPA concentrations increased by 69% after use of polycarbonate bottles (p < 0.0001). The association was stronger among participants who reported > or = 90% compliance (77% increase; p < 0.0001) than among those reporting < 90% compliance (55% increase; p = 0.03), but this difference was not statistically significant (p = 0.54).
One week of polycarbonate bottle use increased urinary BPA concentrations by two-thirds. Regular consumption of cold beverages from polycarbonate bottles is associated with a substantial increase in urinary BPA concentrations irrespective of exposure to BPA from other sources.

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