The Right Chemistry: The research on BPA has been sufficient - polycarbonate plastic
"More research is needed.
"This is the last sentence that is common in scientific papers, especially when studying the effects of environmental chemicals on health.
Many chemical reactions have been occurring in our bodies, exposed to thousands of chemicals, including natural and synthetic ones, and combing the effects of a single substance is a huge challenge.
This raises the question of when the efforts and funding to invest in research chemistry are sufficient.
Is it possible that further research is unlikely to bring about significant revelations, and whether research funding can be better used for alternative projects of biphenol A that are more likely to produce meaningful results, A chemical that has been studied in toxicology literature more than any other literature.
Bisphenol a is quietly cruising under radar as an ingredient in polycarbonate plastic, dental sealant, heat-based paper and epoxy until 1995, a doctoral thesis
David Feldman of Stanford University, entitled "estrogen in unexpected places: possible effects on researchers and consumers", puts it in the spotlight.
Feldman has been studying whether some yeast solution can produce estrogen and has found that it does activate estrogen receptors in the uterus of rats.
But further studies have shown that the substance responsible for the activity is not from yeast, but is filtered out from the polycarbonate flask used during the high pressure sterilization process.
This has stimulated great interest as BPA may be ingested after leaching from epoxy lining in food containers and cans.
Frederick vom Saal of the University of Missouri is one of the researchers interested in BPA.
He has been studying mice treated with estrogen during pregnancy and has found that the prostate size of their male offspring has increased.
Now, he wants to know if bpa with estrogen properties will also produce this effect.
Indeed, Vom Saal issued an alert because he claimed that the dose used was similar to the one that humans might encounter.
While others were unable to reproduce the results of vom Saal's study, his work triggered a lot of research.
Over the past 25 years, more than 8,000 studies have been published on all aspects of BPA.
One would argue that such a massive effort would lead to some reliable conclusions about the health impact of BPA, but that is not the case.
Many researchers have confirmed the estrogen activity of BPA, but found that it is several orders of magnitude lower than the estrogen naturally produced in the body-estrogen.
The rapid elimination of oral intake of BPA in urine also has a good consistency.
In addition to this, one can pick studies that show that BPA is associated with obesity, developmental problems, infertility, cancer, heart disease, and diabetes.
Or pick those that do not have any connection to these conditions.
Health Canada, the FDA, the European Food Safety Agency and many other regulators have carefully reviewed the data and concluded that BPA does not pose a risk at the level of co-exposure.
But some scientists who build their careers on the basis of demonizing BPA disagree and urge all possible measures to be taken to reduce exposure.
They also called for more research, although 8,001 stresearch seems unlikely to clarify in some way the ambiguity presented by the previous 8,000 stresearch.
Nevertheless, the study continues.
However, it is doubtful how much new data has increased the existing knowledge system.
A recent study concluded that female mice exposed to BPA were more lazy at night than the control group.
It's hard to see how it relates to us.
In another case, the researchers calculated how much BPA the student had taken in the school canteen.
Eating pizza, milk, fresh fruits and vegetables is associated with a small amount of BPA, while foods eaten with canned fruits and vegetables can reach up to 1.
19 micrograms per kilogram.
But even so, it is less than half the safety dose that the most cautious regulators consider safe.
By the way, BPA has never been present in plastic polyester used for bottled beverages.
Given that the main regulator does not believe that populations are exposed to unsafe levels of BPA and is already working to find alternatives to chemicals, it seems appropriate to devote research work and funding to more pressing needs.