Analytical Techniques To Measure BPA (Bisphenol A) Levels Used By US FDA And Other Regulatory Bodies Worldwide Deeply Flawed
Source : Thailand Medical News Dec 06, 2019 5 years, 2 weeks, 3 days, 7 hours, 44 minutes ago
-Real exposure levels to the endocrine disruptor and carcinogenic chemical could be as could be as high as 44 times more, raising questions as to whether it was a deliberate attempt.
Washington State University researchers have developed a more accurate method of measuring
bisphenol A (
BPA) levels in humans and found that exposure to the
endocrine-disrupting chemical is far higher than previously assumed.
The disturbing results from the study was published in the journal the
Lancet Diabetes & Endocrinology on Dec. 5 and provides the first evidence that the measurements relied upon by regulatory agencies, including the U.S. Food and Drug Administration, are flawed, underestimating exposure levels by as much as 44 times.
Dr Patricia Hunt, Washington State University professor and corresponding author on the paper told
Thailand Medical News via a phone interview, "This study raises serious concerns about whether we've been careful enough about the safety of this chemical. 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."
Bisphenol A or
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.
Even with experimental evidence, the US 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. This paper challenges that assumption and raises questions about other chemicals, including
BPA replacements, that are also assessed using indirect methods.
Dr Roy Gerona,a collague of Dr Hunt and who herself is an assistant professor at University of California, San Francisco, developed a direct way of measuring
BPA that more accurately accounts for
BPA metabolites, the compounds that are created as the chemical passes through the human body.
In the past, most studies had to rely on an indirect process to measure
BPA metabolites, using an enzyme solution made from a snail to transform the metabolites back into whole
BPA, which could then be measured.
The new method is able to directly measure the
BPA metabolites themselves without using the enzyme solution.
A research team comprised of Gerona, Hunt and Fredrick vom Saal of University of Missouri compared the two methods, first with synthetic urine spiked with
BPA and then with 39 human samples. They found much high
er levels of
BPA using the direct method, as much as 44 times the mean reported by the National Health and Nutrition Examination Survey (NHANES). The disparity between the two methods increased with more
BPA exposure: the greater the exposure the more the previous method missed.
Dr Gerona, the first author on the paper, said more replication is needed .He added, "I hope this study will bring attention to the methodology used to measure
BPA, and that other experts and labs will take a closer look at and assess independently what is happening."
The team is conducting further experiments into
BPA measurement as well as other chemicals that may also have been measured in this manner, a category that includes environmental phenols such as parabens, benzophenone, triclosan found in some cosmetics and soaps, and phthalates found in many consumer products including toys, food packaging and personal care products.
Dr Gerona said,"
BPA is still being measured indirectly through NHANES, and it's not the only endocrine-disrupting chemical being measured this way. Our hypothesis now is that if this is true for
BPA, it could be true for all the other chemicals that are measured indirectly."
Reference: BPA: have flawed analytical techniques compromised risk assessments?
Roy Gerona, Frederick S vom Saal, Patricia A Hunt , THE LANCET
Published: December 05, 2019DOI:https://doi.org/10.1016/S2213-8587(19)30381-X
