BACKGROUND: Bisphenol A (BPA) is an estrogenic contaminant of food and water associated with adverse developmental effects in laboratory animals. BPA has recently been linked to morbidity in adult humans, but studies of developmental effects in humans are methodologically more difficult. The ability to measure BPA in urine samples after long-term storage could aid in such studies. Because the half-life of BPA is < 6h, a single measurement would be useful only if the environmental exposure is relatively constant over weeks or months. Our aims were to evaluate the stability of BPA in specimens after 22-24 years of storage and to measure within-person temporal variability in urinary BPA. METHODS: We measured total BPA concentration by mass spectrometry in first-morning urine samples from 60 premenopausal women. We selected from each woman's stored daily collections three urine samples approximately 2 and 4 weeks apart. Samples were selected from both the follicular and luteal phases of the menstrual cycle to assess cycle effects. Temporal variability was assessed with mixed model regression and correlations. RESULTS: BPA levels had an inter-quartile range from 1.1 to 3.1 ng/mg creatinine, slightly higher than levels in specimens from NHANES collected 3-11 years later. The Spearman correlation was approximately 0.5 for samples 2 weeks apart and 0.3 for samples 4 weeks apart. Menstrual cycle phase did not influence levels. BPA tended to increase during the three-year collection period, but not significantly. CONCLUSIONS: The similar distribution to NHANES samples and correlation of BPA levels taken at 2-week intervals provide indirect evidence that BPA is relatively stable during long-term freezer storage. The correlations indicate generally stable exposures over periods of weeks. These findings suggest that developmental effects of BPA exposure could be investigated with measurements from stored urine.
BACKGROUND:Bisphenol A (BPA) is an estrogenic contaminant of food and water associated with adverse developmental effects in laboratory animals. BPA has recently been linked to morbidity in adult humans, but studies of developmental effects in humans are methodologically more difficult. The ability to measure BPA in urine samples after long-term storage could aid in such studies. Because the half-life of BPA is < 6h, a single measurement would be useful only if the environmental exposure is relatively constant over weeks or months. Our aims were to evaluate the stability of BPA in specimens after 22-24 years of storage and to measure within-person temporal variability in urinary BPA. METHODS: We measured total BPA concentration by mass spectrometry in first-morning urine samples from 60 premenopausal women. We selected from each woman's stored daily collections three urine samples approximately 2 and 4 weeks apart. Samples were selected from both the follicular and luteal phases of the menstrual cycle to assess cycle effects. Temporal variability was assessed with mixed model regression and correlations. RESULTS:BPA levels had an inter-quartile range from 1.1 to 3.1 ng/mg creatinine, slightly higher than levels in specimens from NHANES collected 3-11 years later. The Spearman correlation was approximately 0.5 for samples 2 weeks apart and 0.3 for samples 4 weeks apart. Menstrual cycle phase did not influence levels. BPA tended to increase during the three-year collection period, but not significantly. CONCLUSIONS: The similar distribution to NHANES samples and correlation of BPA levels taken at 2-week intervals provide indirect evidence that BPA is relatively stable during long-term freezer storage. The correlations indicate generally stable exposures over periods of weeks. These findings suggest that developmental effects of BPA exposure could be investigated with measurements from stored urine.
Authors: Frederick S vom Saal; Benson T Akingbemi; Scott M Belcher; Linda S Birnbaum; D Andrew Crain; Marcus Eriksen; Francesca Farabollini; Louis J Guillette; Russ Hauser; Jerrold J Heindel; Shuk-Mei Ho; Patricia A Hunt; Taisen Iguchi; Susan Jobling; Jun Kanno; Ruth A Keri; Karen E Knudsen; Hans Laufer; Gerald A LeBlanc; Michele Marcus; John A McLachlan; John Peterson Myers; Angel Nadal; Retha R Newbold; Nicolas Olea; Gail S Prins; Catherine A Richter; Beverly S Rubin; Carlos Sonnenschein; Ana M Soto; Chris E Talsness; John G Vandenbergh; Laura N Vandenberg; Debby R Walser-Kuntz; Cheryl S Watson; Wade V Welshons; Yelena Wetherill; R Thomas Zoeller Journal: Reprod Toxicol Date: 2007-07-27 Impact factor: 3.143
Authors: Iain A Lang; Tamara S Galloway; Alan Scarlett; William E Henley; Michael Depledge; Robert B Wallace; David Melzer Journal: JAMA Date: 2008-09-16 Impact factor: 56.272
Authors: Catherine A Richter; Linda S Birnbaum; Francesca Farabollini; Retha R Newbold; Beverly S Rubin; Chris E Talsness; John G Vandenbergh; Debby R Walser-Kuntz; Frederick S vom Saal Journal: Reprod Toxicol Date: 2007-06-26 Impact factor: 3.143
Authors: Xiaoyun Ye; Amber M Bishop; John A Reidy; Larry L Needham; Antonia M Calafat Journal: J Expo Sci Environ Epidemiol Date: 2007-04-04 Impact factor: 5.563
Authors: A J Wilcox; C R Weinberg; J F O'Connor; D D Baird; J P Schlatterer; R E Canfield; E G Armstrong; B C Nisula Journal: N Engl J Med Date: 1988-07-28 Impact factor: 91.245
Authors: Milena Durando; Laura Kass; Julio Piva; Carlos Sonnenschein; Ana M Soto; Enrique H Luque; Mónica Muñoz-de-Toro Journal: Environ Health Perspect Date: 2007-01 Impact factor: 9.031
Authors: Qi Sun; Kimberly A Bertrand; Adrian A Franke; Bernard Rosner; Gary C Curhan; Walter C Willett Journal: Am J Clin Nutr Date: 2016-11-09 Impact factor: 7.045
Authors: Pahriya Ashrap; Deborah J Watkins; Antonia M Calafat; Xiaoyun Ye; Zaira Rosario; Phil Brown; Carmen M Vélez-Vega; Akram Alshawabkeh; José F Cordero; John D Meeker Journal: Environ Int Date: 2018-10-11 Impact factor: 9.621
Authors: Shaina L Stacy; Melissa Eliot; Antonia M Calafat; Aimin Chen; Bruce P Lanphear; Russ Hauser; George D Papandonatos; Sheela Sathyanarayana; Xiaoyun Ye; Kimberly Yolton; Joseph M Braun Journal: Environ Sci Technol Date: 2016-05-23 Impact factor: 9.028
Authors: Kathleen M Donohue; Rachel L Miller; Matthew S Perzanowski; Allan C Just; Lori A Hoepner; Srikesh Arunajadai; Stephen Canfield; David Resnick; Antonia M Calafat; Frederica P Perera; Robin M Whyatt Journal: J Allergy Clin Immunol Date: 2013-03 Impact factor: 10.793
Authors: Anna Z Pollack; Neil J Perkins; Lindsey Sjaarda; Sunni L Mumford; Kurunthachalam Kannan; Claire Philippat; Jean Wactawski-Wende; Enrique F Schisterman Journal: Environ Res Date: 2016-08-25 Impact factor: 6.498
Authors: Laura N Vandenberg; Ibrahim Chahoud; Jerrold J Heindel; Vasantha Padmanabhan; Francisco J R Paumgartten; Gilbert Schoenfelder Journal: Environ Health Perspect Date: 2010-03-23 Impact factor: 9.031