That whole business about drinking water out of plastic bottles that we thought was taken care of is suddenly back on the radar of things to worry about. Remember how bisphenol-A (BPA), the additive added to plastics, became such a big deal? For some reason plastic manufacturers decided it was safe to add into plastics and the government regulators who should have kept an eye on them, turned a blind eye. The government never did intervene in a meaningful way; it was the public that responded to the science suggesting it might not be a healthy practice to have BPA leaching into our food supply and started avoiding plastic food and beverage containers. Our kitchen cupboard once filled with Nalgene bottles is fully restocked with stainless steel bottles, just for example. Then we started seeing new plastic bottles labeled as BPA-free and people all breathed a sigh of relief and found other things to worry about. Now it seems we were a bit naïve: the chemical that is now substituted for BPA in plastics may actually be worse.
A newly published study reports that BPA’s replacement, BPS not only hinders cardiac function but it does so far faster than the researchers predicted. The study comes from theUniversity of Guelph in Canada. That country actually banned bisphenol A (BPA from baby bottles in Canada in 2010 over concerns that it leached into foods and cause hormone-related side effects. Most manufacturers now use BPS as a replacement for BPA in their products and label them as BPA-free. 
The Guelph study is the first to show the instant effects bisphenol S (BPS) can have on the heart.
“We expected to find similar effects from BPS as we have with BPA, but not at the speed that it worked,” said biomedical sciences professor Glen Pyle, who conducted the study with former master’s student Melissa Ferguson. “This replacement chemical seems to be more potent.”
When mice were given bisphenol BPA or BPS in amounts that mimicked typical human levels, their heart function worsened, especially in females, within minutes of exposure. These findings are concerning, as endocrine receptors and metabolic pathways are similar in mice and humans, said Pyle. 
“This study raises concerns about the safety of BPS as a replacement for BPA.”
It’s particularly worrisome for people with coronary heart disease, high blood pressure, diabetes or obesity, because the effects of BPS could increase the chance of a heart attack or make a heart attack more severe, he added.
“If the heart is in a precarious position, when you add a stressor you can make it worse.”
Published recently in the journal Scientific Reports, the study entailed treating mouse hearts with BPA and BPS at levels typically seen in people. Each chemical on its own was found to depress heart function by dampening heart contractions causing slower blood flow. However, BPS had a quicker impact — within five minutes of exposure.
“Previous research has looked at the chronic effects that can happen when exposed to BPS over days,” said Pyle. “But we are the first to show how fast BPS can work. This is an important finding because it means you don’t need to have a buildup of the chemical over time to experience its harmful effects.”
BPA is found in plastics used for food packaging, including liners for metal cans and other containers, as well as in medical devices such as hospital intravenous lines and dental sealants. Although the body gets rid of bisphenols quickly, their ubiquitous use in so many consumer goods means that the substance persists.
Pyle advocates banning the substitute chemical BPS from such consumer products as food and beverage packaging, toys and thermal paper receipts. He also suggests consumers reduce plastic use, including single-use plastics.
This news is not actually a surprise. Back in 2015 a similar report was published raising concerns about bisphenol-S. At the time the researchers suggested “Evaluation of the bioactivity and safety of BPS and other BPA analogs is necessary before they are used as BPA alternatives in consumer products” That doesn’t seem to be the case.
A 2016 review (that is worth reading) states what would seem to be an obvious problem; “The real issue is that the industry is replacing a toxic chemical with another, yet untested chemical, which will require large investments of research funds to carry out applicable studies….. Notably, in addition to BPA and BPS, other bisphenols, including bisphenol F and BPA diglycidyl ether, also have endocrine-disrupting properties….”
Especially disturbing though is the how fat cells respond to BPS; they make more fat faster. The thought that BPS may be aggravating an obesity epidemic is receiving considerable attention. One can debate which of the various potential dangers of BPS exposures is the most important.  Just because of our long focus on cancer, I would tend to worry most about risk of breast cancer from exposure , but others might put their concerns higher on the list. The bottom line though is that this stuff does not seem any better for our health than the original BPA.
Packaging labels that promote something as BPA-Free are not to be trusted; the statement may be true but the intent is deeply deceptive.
 https://www.sciencedaily.com/releases/2020/01/200109130211.htm Science Daily: BPA replacement, BPS, hinders heart function, study reveals. January 9, 2020.
 Ferguson M, Lorenzen-Schmidt I, Pyle WG. Bisphenol S rapidly depresses heart function through estrogen receptor-β and decreases phospholamban phosphorylation in a sex-dependent manner. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-019-52350-y
Full Text Free: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6828810/
 Gao X1, Ma J, Chen Y, Wang HS. Rapid responses and mechanism of action for low-dose bisphenol S on ex vivo rat hearts and isolated myocytes: evidence of female-specific proarrhythmic effects. Environ Health Perspect. 2015 Jun;123(6):571-8.
 Ben-Jonathan N, Hugo ER. Bisphenols Come in Different Flavors: Is “S” Better Than “A”? Endocrinology. 2016 Apr;157(4):1321-3.
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 Wu LH, Zhang XM, Wang F, et al. Occurrence of bisphenol S in the environment and implications for human exposure: A short review. Sci Total Environ. 2018 Feb 15;615:87-98.
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