Cheryl Rosenfeld, a Bond Life Sciences Center investigator and professor of biomedical sciences at the University of Missouri. | photo by Jinghong Chen, Bond LSC
What companies aren’t telling you about their merchandise
By: Samantha Kummerer, Bond LSC
Bisphenol A, otherwise known as BPA, is used to make plastic containers, coats the inside your metal food cans, and leaches into your food and water.
BPA has concerned scientists, health practitioners and the general public for many years because of its potential to mimic hormones and disrupt the developmental stages in animals.
Opposition to the chemical has led to certain manufacture’s marketing their items, such as food containers and water bottles, as“BPA–Free” and a global push to reduce the usage of BPA in commonly used household-items.
However, new evidence suggests consumers may not be as ‘free’ from harm as they think.
Bond Life Sciences Center researcher Cheryl Rosenfeld suggested that many consumers might not be aware of how these alternatives are made. BPA-substitutes — bisphenol S (BPS), bisphenol F (BPF) and bisphenol AF (BPAF) — aren’t too different from BPA chemically.
“They’re just playing with various synthetic structures is what many industrials groups are doing,” she said.
BPA is made up of two chemical compound groups called phenols. Picture two rings with different elements connected. In BPF, BPS and BPAF all those same parts are still present, and the only change is that the rings are rotated differently and contain various branching chemicals .
Since these alternate chemicals are structurally similar to BPA, they still bind to estrogen receptors, receptors to which the natural hormone estrogen binds and activates, which results in up- or down-regulation in the expression of various genes.
“The worst problem is that humans and animals are unknowingly serving as test subjects. Industrial companies are not required to show definitive evidence that these alternatives to BPA are safe. They can cite their own limited studies, but currently, no rigorous testing is required for these BPA-alternative chemicals that are being to flood the market. There is no requirement for the products that contain these chemicals to state as such. Thus, consumers cannot make educated decisions when purchasing various food and beverage products,” Rosenfeld said speaking of the industry.
Substitutes aren’t always better
Rosenfeld recently published a literature review exploring the use of the BPA-alternatives and their potential risk. She began the work out of curiosity since her Bond LSC lab studies the harmful effects of BPA.
After putting the puzzle pieces together, the big picture began to emerge that exposure of rodent models to these substitute chemicals exert analogous effects as BPA — depressive behaviors, increased anxiety, decrease in social behavior and decreased maternal/paternal care. In some cases, the alternatives have an even greater effect, according to Rosenfeld.
Production of the industrial chemical, BPA, began in the mid 1900’s to make plastics. Today, it can be found in everything from water bottles to storage containers and even food. With this increase exposure comes an increased risk to consumers.
Past studies linked exposure to the chemical with health effects on the brain and behavior and many other widespread effects.
When BPA enters the body, the can at least partially metabolize and break down the chemical via enzymes, which is then removed from the body. But there is a limited supply of such metabolizing enzymes used and those consuming BPA daily will end up overwhelming their body’s ability to metabolize and eliminate it with the net effect that BPA can accumulate over time and continue to exert potential harmful effects.
The most serious effect of BPA and now the substitutes happens during development. Fetuses have poorability to break down the chemical. Evidence links BPA exposure during development with neurological disorders like autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD).
Most studies have examined the effects of BPA alternatives in rodents and zebrafish. While numerous factors prevent scientists from establishing causation in humans, Rosenfeld suggested it is time to at least start correlating early life exposure to BPA alternatives and risk of neurobehavioral disorders, including ASD, ADHD, and other neurodegenerative disorders.
“What’s worrisome is the women who are seeking to become pregnant or are currently pregnant, they are under the impression that they are making positive choices for their sons and daughters by using BPA-free products, but such products likely contain these BPA-substitute chemicals that can result in equal and possibly even greater negative consequences for their unborn offspring. Ultimately, the question is then what sort of products should be using?” Rosenfeld explained.
Humans aren’t alone in the impact. Rosenfeld explained these chemicals don’t break down in the environment and could play a part in the decline of certain animals. Previous studies by Rosenfeld’s lab and others at MU revealed BPA has the ability to feminize what should otherwise be male turtles.
“I just wish we could stop and pause and think about the havoc we are wrecking on our own environment and ourselves,” she said.
Without definitive results, a lot of unanswered questions remain. Future studies will likely explore the full range of effects caused by the BPA alternatives. Rosenfeld is calling for researchers to begin to treat these alternatives like BPA and put them through rigorous studies. These studies, however, come with a cost.
Rosenfeld’s lab is funded for BPA research. To add these additional chemicals to her current studies, the cost would double and triple due to the increased amount of animal test subjects that would be required.
“They keep upping the bar of how many replicas we have to test. If you want to show effects, if you want us to believe your results, we have to test 12-15 animals, well then you need to test another 12-15 animals in these groups and then your research dollars are all-of-a-sudden gone,” Rosenfeld said.
Research costs are going up and in the meantime BPA is still being produced in high quantities, so the industry as a whole has to decide where to allocate its funds.
“It’s a moving target. We’re trying to keep up and they keep synthesizing more and more chemicals everyday. The problem is we are completely outspent in terms of avaibable research dollars compared to the money industrial companies have on hand to fight tighter reguation. It’s not even a fair fight,” she said.
Rosenfeld hopes this new publication prompts scientists and the public to begin to question and call for more action on testing these pervasive BPA subsitutes. The silver lining is even though we can’t control our exposure to these chemicals, Rosenfeld hopes we might be able to find a way to combat our exposure.
Cheryl Rosenfeld is a Biomedical Sciences professor,a researcher in Bond Life Sciences Center, and research faculty member in the Thompson Center for Autism and Neurobehavioral Disorders. Rosenfeld specializes in how the early in utero environment can shape later offspring health, otherwise considered developmental origins of health and disease (DOHaD)She earned her bachelors and doctor of veterinary medicine degrees from the University of Illinois and her PhD from the University of Missouri.