This piece originally appeared in the San Francisco Chronicle.
Activists and some politicians are exploiting San Francisco's children, and their parents' legitimate concerns for their health, by convincing the city government to ban the sale, distribution or manufacture of toys or child-care products if they contain certain chemicals. This ban, which is now being challenged in court by a group of chemical manufacturers, toymakers and retailers, who claim state law pre-empts city ordinance, would make San Francisco unique in the world, and -- unlike so many of the city's wonderful attributes -- not in a good way.
One of the target chemicals, bisphenol A, has been used in many familiar guises for decades, with little evidence of harm to humans of any age. Bisphenol A is quite common, indeed almost ubiquitous, considering its many uses. Among the most common: plastic bottles of many types -- it's required in the manufacture of shatter-proof polycarbonate plastic, a material invaluable in baby bottles, bike helmets and protective car-seats, eyeglass lenses and medical devices of many kinds. The resin coatings that protect the integrity of canned food and beverages as well as most electronic circuit boards also depend on bisphenol A.
So, given these important uses, what's all the fuss about? Bisphenol A is known to be weakly estrogenic in the lab, and it has been claimed that low doses of hormonally active substances in the environment may cause health problems, but this allegation is highly controversial. A few of the many studies by government-sponsored as well as private researchers have suggested possible risks but have not shown any evidence of adverse effects in humans. My organization, the American Council on Science and Health, just published peer-reviewed scientific assessment of the available data, including both animal and human studies, and found no compelling evidence that people are being put at risk by the tiny levels of exposure to bisphenol A. The so-called "low-dose hypothesis" is just that -- an unproven hypothesis.
Because bisphenol A may be found in our bodies -- although at extremely minute amounts -- some groups have seized upon this as an excuse to frighten parents and to seek government and media attention. But even the federal Centers for Disease Control and Prevention has stated that the mere presence of a substance in our bodies does not mean that it is harmful.
Activists periodically pick up on these issues and start pressuring politicians to ban or restrict consumer products, based on hypothetical dangers such as this one. Indeed, a ban much like this was proposed by former Assemblywoman Wilma Chan at the state level last year, and was swatted away for the unscientific nuisance it is -- an interesting response in a state whose Proposition 65 is among the most stringent of efforts at consumer protection in the nation.
If San Francisco takes a harder line on bisphenol A than the State of California, and even the U.S. Food and Drug Administration, what will be the next target? Perhaps the San Francisco Board of Supervisors will start banning food ingredients.
What will replace bisphenol A and other banned chemicals in the many applications they are essential for? Will glass replace shatter-proof baby bottles? Will some other chemical replace it in bike helmets -- only to come under attack in a year or two, because the safety record of any replacement will be more suspect than this well-known substance?
Let's not throw out the baby bottles with the bath water. Let's hope the folks in charge of these regulations come to their senses -- or that the court sends them a wake-up call, before it is too late.
