Why Hasn’t Bisphenol A (BPA) Been Banned Completely?

“The number of new chemicals is increasing exponentially, with approximately 12,000 new substances added daily…”—yet data aren’t available on the hazards of even some of the high-volume chemicals. Bisphenol A (BPA) is one of the highest volume chemicals, with billions of pounds produced each year. Studies have raised concerns about its possible implication in the cause of certain chronic diseases, such as diabetes, obesity, reproductive disorders, cardiovascular diseases, birth defects, chronic respiratory diseases, kidney diseases, and breast cancer. Given this, BPA is the topic of my video Why BPA Hasn’t Been Banned.

A new study on the health implications of BPA comes out nearly every week. BPA was first developed over a hundred years ago as a synthetic estrogen, but it wasn’t until the 1950s that industry realized it could be used to make polycarbonate plastic, and “BPA rapidly became one of the most produced and used chemicals worldwide, even though it was a recognized synthetic estrogen” with hormonal effects. About a billion pounds are also used to line food and beverage cans, especially for tuna and condensed soups.

Today, nearly all of us, including our children, have BPA in our bodies, but not to worry: The government says up to 50 µg/kg per day is safe. Even those working in Chinese BPA factories don’t get exposed to more than 70 times lower than that so-called safety limit. Why then did exposure seem to affect male workers’ sperm counts? In the United States, the general population gets less than a thousand times lower than the safety limit, yet, even at those incredibly low doses, we still seem to be seeing adverse effects on thyroid function, weight control, blood sugar control, cardiovascular disease, liver function, and immune function. Indeed, “[t]he fact that there are significant adverse effects in populations exposed to BPA at concentrations [thousands of] times lower than the TDI [tolerable daily limit]…indicates that the safe exposure to BPA may be much lower than previously thought in humans.” Despite this, the limit hasn’t been changed. BPA has been banned from “baby bottles and sippy cups,” but nearly unlimited doses are still apparently okay for everyone else. What’s the disconnect?

It has to do with the fascinating world of low-dose effects of hormone-disrupting chemicals. “For decades, studies of endocrine-disrupting chemicals (EDCs) have challenged traditional concepts in toxicology, in particular the dogma of ‘the dose makes the poison’”—that is, the concept “that lower exposures to a hazardous compound will therefore always generate lower risks.” Indeed, that is the core assumption underlying our system of chemical safety testing. Researchers start giving animals in laboratories a super-high dose and then keep lowering the dosage until whatever adverse effects that had occurred disappear. Then, they add a safety buffer and assume everything below that dose should be okay, assuming a straight line showing the higher the dose, the higher the effect. However, hormone-disrupting chemicals can have all sorts of curious curves. How is it possible that something could have more of an effect at a lower dose?

A study was done to see whether BPA suppressed an obesity-protective hormone in fat samples taken from breast reduction and tummy tuck patients. At 100 nanomoles of BPA, hormone levels were no lower than they were at 0nM of BPA. And, since most people have levels between 1 and 20, BPA was considered to be safe. But, although there was no suppression at 0 and no suppression at 100, at the levels actually found in people’s bodies, BPA appeared to cut hormone release nearly in half.

As the world’s oldest, largest, and most active organization devoted to research on hormones concluded, “even infinitesimally low levels of exposure—indeed, any level of exposure at all—may cause [problems].” In fact, it may come to nearly $3 billion in problems every year, counting the estimated effects of BPA on childhood obesity and heart disease alone. There are alternatives the industry can use. The problem, though, is that they may cost companies two cents more.


Related videos about BPA include BPA on Receipts: Getting Under Our Skin and Are the BPA-Free Alternatives Safe?

 BPA isn’t the only problem with canned tuna. Check out:

What can we do to avoid endocrine-disrupting chemicals? See, for example, Avoiding Adult Exposure to Phthalates and How to Avoid the Obesity-Related Plastic Chemical BPA.

Alkylphenols are another group of endocrine-disrupting chemicals. To learn more about them, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

Estrogenic Growth Promoters in Meat

In 1979, an epidemic of breast enlargement was noted in Italian children. Poultry or veal was suspected, given that estrogens “may be fed to farm animals to accelerate their weight gain.” “After this episode, the European Union banned the application/use of anabolic growth promoters in agriculture,” as well as the importation of American meat from animals injected with drugs like Zeranol, sold as “Ralgro Magnum.”

Zeranol, one of the most potent known endocrine disrupters, is 100,000 times more estrogenic than the plastics chemical, BPA, for example, and is the subject of my video Zeranol Use in Meat and Breast Cancer. “Zeranol constitutes a special case among potential endocrine disrupters, because Zeranol, in contrast to all other oestrogenic ‘endocrine disrupting’ chemicals, is present in human food because it is deliberately used in the production of consumer products. Furthermore, Zeranol is designed to be a potent, fairly persistent, [estrogen] whereas the [estrogenic] properties of the chemicals that are considered potential endocrine disrupters is accidental.”

If you drip blood from a cow implanted with the drug onto human breast cancer cells in a petri dish, you can double the cancer growth rate. We don’t drink blood, though, but preliminary data showed that muscle extracts—that is, meat extracts—also stimulated breast cancer cell proliferation.

Furthermore, Zeranol may cause the transformation of normal breast cells into cancer cells in the first place. Zeranol-containing blood from implanted cattle “was capable of transforming the human normal breast epithelial cell line” into breast cancer cells within 21 days.

“[O]bese individuals may be at greater risk of developing zeranol-induced breast cancer,” since they already have high levels of leptin, which is a hormone produced by fat cells that can itself promote breast cancer growth. And, Zeranol exposure can greatly enhance this growth-promoting action. “This result also suggests that Z[eranol] may be more harmful to obese breast cancer patients than to normal weight breast cancer patients in terms of breast cancer development.”

“In conclusion, because the synthetic and the natural hormones, used as anabolic growth promoters in meat production, are by far the most potent hormones found in human food,” we should really be testing people, especially children, before and after eating this meat. It amazes me this hasn’t been done, and, until it has, we have no idea what kind of threat they may pose, though the fact that Zeranol is as potent as estradiol (the primary sex steroid in women) and DES should concern us. DES is another synthetic estrogen that was marketed to pregnant women until 1971 when it was shown to cause vaginal cancers in the daughters. But few know it was also used in meat.

“In the absence of effective federal regulation, the meat industry uses hundreds of animal feed additives…with little or no concern about the carcinogenic and other toxic effects of dietary residues of these additives. Illustratively, after decades of misleading assurances of the safety of diethylstilbestrol (DES) and its use as a growth-promoting animal-feed additive, the United States finally banned its use in 1979 some 40 years after it was first shown to be carcinogenic. The meat industry then promptly switched to other [potentially] carcinogenic additives,” such as Zeranol.

When girls started dying from vaginal cancer, DES-treated meat was banned in Europe. However, “misleading assurances…including the deliberate suppression of residue data, managed to delay a U.S. ban on DES” in the meat supply for eight years.

Today, “[v]irtually the entire U.S. population consumes, without any warning, labeling, or information, unknown and unpredictable amounts of hormonal residues in meat products over a lifetime.” If all hormonal and other carcinogenic feed additives aren’t banned immediately, the least we should have is “explicit labeling requirements of use and of [hormone] residue levels in all meat products, including milk and eggs.”


Isn’t the DES story amazing? I had no idea it was used in meat production. Check out Illegal Drugs in Chicken Feathers for more on Big Pharma on Big Farms.

The most dangerous additive used in the meat industry is antibiotics, though. See, for example:

For more on what may be bad for the breast, check out:

And, for what may be protective, see:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations:

How Plastics Can Affect Your Love Life

Most of the attention on phthalates, a group of hormone-disrupting chemicals found in PVC plastics, has been focused on fetal and child health, particularly regarding genital and behavioral development. Recent data have shown, for example, “incomplete virilization in infant boys” and reduced masculine play as they grow up, and for girls, an earlier onset of puberty. What about affecting hormonal function in adults? I explore this in my video Avoiding Adult Exposure to Phthalates.

Men exposed to high levels of phthalate had lower testosterone levels, but that was for workers in a plastics plant. In the general population, the evidence is mixed. A study in Sweden of men in their 20s found no effect on testosterone, whereas a U.S. study on men in their 30s did find an effect, even at levels of exposure much lower than those of factory workers. When there’s conflicting evidence like this, ideally we’d put it to the test, but you can’t ethically expose people to phthalates so scientists have come up with convoluted methods like implanting the testicles from human fetuses into mice to keep them growing. We want to know about the effects on adult, not fetal, testicles, which had been harder to procure… until recently. “[C]onsent was obtained from all donors.” Now, I’ve heard of blood donors, but this is a whole other level. Researchers obtained donated testicles from prostate cancer patients who underwent castration to control their disease and, indeed, were able to get direct evidence that phthalates can inhibit testosterone production at the kinds of levels one sees in general population studies.

What about breast cancer, the number-one cancer killer of young women? Women working in automotive plastics and food canning are at five times the odds of breast cancer, suggesting a link. In a petri dish, however, phthalates didn’t seem to accelerate breast cancer growth at the levels of exposure expected in the general population. More recently, though, phthalate exposure was found to boost breast cancer cell growth in vitro at the levels found circulating in the bodies of many women. Therefore, the maximum tolerable dose set by governments should be re-evaluated.

How do you avoid the stuff? Well, when you think of plastic chemicals, you may think of water bottles, but they appear to play only a minor role. Most phthalates come from food. How do we know this? If you take people and have them stop eating for a few days, you get a significant drop in the amount of phthalates spilling into their urine. Fasting isn’t exactly sustainable, though. Thankfully, we can see similar drops from simply eating a plant-based diet for a few days, which gives us a clue as to where most phthalates are found. There were a few cases of spikes within the fasting period after showers, however, suggesting contamination in personal care products.

We can counsel patients to reduce phthalate exposures by avoiding the use of scented personal care products, soaps, and cosmetics, since phthalates are used as a fragrance carrier. Phthalates can also be found in children’s toys, as well as adult toys. “On behalf of the Danish [Environmental Protection Agency] EPA, [the Danish Technological Institute] DTI has made inquiries about the consumption pattern in connection with the use of sex toys made of rubber or plastics” to see what kind of exposure one might get “based on worst case scenarios.” Those working behind the counters at sex shops “proved to possess very little knowledge of the materials,” so the researchers had to do their own testing. It turns out that “jelly” is plasticized PVC—up to two-thirds phthalates by weight. Though the use of water-based lubricants may reduce the health risks 100-fold, phthalate exposure through lubricants may still have the opposite of the intended effect. Women with the highest levels of phthalates flowing through their bodies “had over 2.5 times the odds of reporting a lack of interest in sexual activity,” and these weren’t women in a canning factory, rather they were at typical exposure levels in America.


To find out how to lower your exposure to phthalates, see What Diet Best Lowers Phthalate Exposure?

More on hormone-disrupting chemicals in our food supply in:

Interested in learning more about improving sexual health? See:

In health,
Michael Greger, M.D.

PS: If you haven’t yet, you can subscribe to my free videos here and watch my live, year-in-review presentations: