THURSDAY, Jan. 29 (HealthDay News) -- Bisphenol A, an industrial chemical used in the manufacture of polycarbonate plastics, epoxy resins and polyvinyl chloride plastic, may accumulate in body tissue or be ingested via substantial non-food sources, according to study findings published online Jan. 28 in Environmental Health Perspectives.
Richard W. Stahlhut, M.D., and colleagues at the University of Rochester Medical Center in Rochester, N.Y., analyzed data on 1,469 participants in the 2003-2004 National Health and Nutrition Examination Survey, and looked at the urine concentration of human bisphenol A as a factor of fasting time.
Among the 441 subjects who fasted for 4.5 to 8.5 hours, there was a significant decline in bisphenol A levels, with a population-based half-life of 4.1 hours, but at shorter (zero to 4.5 hours) and longer (8.5 to 24 hours) fasting times, there was no significant decline in bisphenol A levels, the investigators found. Fasting time was not a useful predictor of highest or lowest levels of bisphenol A, the researchers report.
"Risk assessments for bisphenol A have been based in part on evidence that: 1) food is the primary, and almost exclusive, exposure source, and 2) rapid and complete bisphenol A elimination occurs after exposure," the authors write. "The persistence of population bisphenol A levels despite extended fasting appears to contradict this evidence."