|
 Longstanding tests for human BPA exposure have relied on an enzyme
solution made from snails to transform BPA metabolites - breakdown
products formed as the chemical passes through the body - back into
whole BPA that can then be measured, researchers note in the The
Lancet Diabetes & Endocrinology.
These methods have also long been used by U.S. regulators to set
safety standards for consumer products.
In the current study, researchers compared this old way of assessing
human BPA exposure with a new method that directly measures the BPA
metabolites. They used both the old and new methods to test
synthetic urine spiked with BPA and found that one version of the
old method - one used by the U.S. Food and Drug Administration -
detected just 10% of the BPA.
When they tested the old and new methods on 39 human urine samples,
the new method showed BPA levels up to 44 times higher than the
average exposure levels found in the National Health and Nutrition
Examination Survey - data that was used to set safety standards. The
disparity between the two methods increased with more BPA exposure:
the greater the exposure the more of it the previous method missed.
"This study raises serious concerns about whether we've been careful
enough about the safety of this chemical," said senior study author
Patricia Hunt of Washington State University in Pullman.
"What it comes down to is that the conclusions federal agencies have
come to about how to regulate BPA may have been based on inaccurate
measurements," Hunt said.
BPA can be found in a wide range of plastics, including food and
drink containers, and animal studies have shown that it can
interfere with the body's hormones. In particular, fetal exposure to
BPA has been linked to problems with growth, metabolism, behavior,
fertility and even greater cancer risk.
[to top of second column] |
Despite this experimental evidence, the FDA has evaluated data from
studies measuring BPA in human urine and determined that human
exposure to the chemical is at very low, and therefore, safe levels,
the study team argues. This paper challenges that assumption and
raises questions about other chemicals, including BPA replacements,
that are also assessed using indirect methods, the researchers
conclude.
With inaccurate measurements of BPA, studies on the negative health
effects may have also underestimated risks of exposure to the
chemical, said Dr. Leonardo Trasande, director of the NYU Center for
the Investigation of Environmental Hazards in New York City.
"We may have underestimated the effects of BPA in human studies,"
Trasande, who wasn't involved in the current study, said by email.
The current study was small, and it wasn't designed to determine
whether or how BPA exposure might lead to health problems.
BPA, parabens and antimicrobials are widely used in personal care
products and plastics.
In some previous studies, so-called endocrine-disrupting compounds
such as BPA, parabens and antimicrobials have been shown to
interfere with hormones and have harmful developmental, reproductive
and neurological effects.
"We can't eliminate our exposure, but we can reduce it by avoiding
obvious routes of contamination, e.g., handling of receipts, placing
plastic in the microwave or dishwasher (heat is an invitation for
chemicals to migrate out of plastic), and continuing to use products
that show clear signs of wear and tear (when they are damaged, they
are leaching chemicals)," Hunt said by email.
SOURCE: https://bit.ly/38Okcxu The Lancet Diabetes and
Endocrinology, online December 5, 2019.
[© 2019 Thomson Reuters. All rights
reserved.] Copyright 2019 Reuters. All rights reserved. This material may not be published,
broadcast, rewritten or redistributed.
Thompson Reuters is solely responsible for this content. |
