| Institution: | 1. Division of Biochemical Toxicology, National Center for Toxicological Research, U.S. Food and Drug Administration, Jefferson, AR 72079, USA;2. Health Effects and Exposure Science, Pacific Northwest National Laboratory, Richland, WA 99352, USA;3. Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR 93771, USA;1. Department of Occupational and Environmental Medicine, Ulsan University Hospital, University of Ulsan College of Medicine, Ulsan, South Korea;2. Department of Occupational and Environmental Medicine, Seoul St. Mary?s Hospital, The Catholic University of Korea, Seoul, South Korea;3. Department of Occupational and Environmental Medicine, Soonchunhyang University Hospital, Cheonan, South Korea;4. Korean Industrial Health Association, Seoul, South Korea;1. School of Biological Sciences, Faculty of Science, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region;2. Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, P.O. Box 12233, Research Triangle Park, NC 27709, USA;3. Institute of Public Health and Clinical Nutrition, University of Eastern Finland, Kuopio, Finland |
| Abstract: | Urine and serum biomonitoring was used to measure internal exposure to selected dietary estrogens in a cohort of 30 pregnant women. Exposure was measured over a period comprising one-half day in the field (6 h) and one day in a clinic (24 h). Biomonitoring of the dietary phytoestrogens genistein (GEN), daidzein (DDZ) and equol (EQ), as well as the mycoestrogen, zearalenone (ZEN) and its congeners, was conducted using UPLC-MS/MS. Biomonitoring revealed evidence of internal exposure to naturally occurring dietary estrogens during pregnancy. Urinary concentrations of total GEN, DDZ and EQ were similar to levels reported for general adult U.S. population. Measurable concentrations of total (parent and metabolites) GEN, DDZ and EQ were present in 240, 207 and 2 of 270 serum samples, respectively. Six out of 30 subjects had measurable concentrations of unconjugated GEN and/or DDZ in serum between 0.6 and 7.1 nM. Urine to serum total isoflavone ratios for GEN, DDZ and EQ were 13, 47, and 180, respectively. ZEN and its reductive metabolite, α-zearalenol (α-ZEL), were present in pregnant women (11 out of 30 subjects) as conjugates at levels near the limit of quantification. The average total urinary concentration was 0.10 μg/L for ZEN and 0.11 μg/L for α-ZEL. |
