"I fear that you may have misled your readers, causing them needless anxiety"
By Elizabeth M. Whelan, Sc.D., M.P.H.
Posted: Friday, May 23, 2008
LETTER
Publication Date: May 23, 2008
New York, NY--May 23, 2008. In a letter responding to Harvard's Dr. Claire McCarthy, Dr. Elizabeth M. Whelan, President of the American Council on Science and Health, maintains that the use of plastic bottles and other plastic products pose no known hazard to human health.
In an article published this week in the Harvard Health Letter, by contrast, Dr. McCarthy argued that it was advisable to limit exposure to plastic bottles made with BPA and to children's flexible plastic products made with phthalates because of potential health problems. Dr. Whelan disagrees, retorting that the alleged health hazards of plastic products were based on observations of high-dose rodent studies--which are not in anyway reliable in predicting human health risks.
Dr. Whelan's letter--and a link to Dr. McCarthy's original Harvard Health Letter article--is included below.
May 23, 2008
Dear Dr. McCarthy,
I read with great concern your May 20, 2008 article ("Chemicals in Plastic Baby Products: How Will You Play the Odds?" --
http://www.gather.com/viewArticle.jsp?articleId=281474977349569 ) in the May 20, 2008 Harvard Health Letter. I write in the spirit of professional dialog to point out to you just a few of the errors and discrepancies in your commentary--and to pose to you some questions. I hope that after you consider the issues I raise, you will issue a statement of clarification.
-- You write regarding saccharin that "a study showed that rats fed large amounts of saccharin developed bladder tumors," and you added that "the study was flawed." Actually, the 1977 call for a ban on saccharin (a ban that was rejected by Congress) was based on a study of pregnant rodents exposed to very high doses--and their male offspring had a higher rate of bladder cancer. The study was not really "defective," but after years of analysis, federal scientists concluded it was simply not relevant for predicting human health risks. See the ACSH publication
Facts Versus Fears (
http://www.acsh.org/publications/pubID.154/pub_detail.asp ).
-- You use the word "carcinogen" to refer to chemicals that when ingested in high doses by rodents increase cancer risk. And you postulate that "carcinogens are carcinogens." Actually that statement is not true.
There is a vast difference between the designation of a chemical as a "carcinogen" based on animal laboratory tests and the classification "carcinogen" based on human epidemiology. For example, innumerable natural and manmade chemicals cause cancer in rodents (see below)--but the bona fide human cancer risks have been identified through human studies. Among the better-known examples, cigarette smoking and long-term, intense exposure to sunlight and radiation have proven human carcinogenic effects, as you well know. Exposure to saccharin, traces of dioxin, nitrite, cyclamates--and other "carcinogens du jour" as determined by animal studies--pose no known human cancer risk. In short, a "carcinogen is not a carcinogen."
It may be of interest to you that high-dose animal cancer testing of mice is an unreliable predictor of cancer risk in rats. If such laboratory cancer tests are not even sufficiently reliable to predict from one rodent species to another, isn't it foolish to assume a rodent study will reliably predict human cancer risk? See the ACSH publication
America's War on "Carcinogens" (
http://www.acsh.org/publications/pubID.990/pub_detail.asp ).
--Your commentary is based on the assumption that high-dose rodent tests predict human cancer risk--and that "just in case" we should eliminate or reduce our exposure to any chemical that causes cancer in rodents. Are you aware that a wide variety of common, naturally-occurring chemicals in food are known animal carcinogens? These include the natural chemicals hydrazines in mushrooms, safrole in table pepper, aflatoxin in peanuts, ethyl benzene in coffee, ethyl carbamate in bread, and more.
You advise great caution about exposure to phthalates and bisphenol-A because they are rodent carcinogens. We ask that you examine the publication
ACSH Holiday Dinner Menu (
http://www.acsh.org/publications/pubID.103/pub_detail.asp ), which reveals that a multi-course meal of natural food is replete with chemicals that cause cancer in rodents. In addition to recommending reduced exposure to BPA and phthalates because of rodent carcinogenicity data, would you also recommend out of prudence that consumers (and their kids) not eat mushrooms, peanut butter, and a full spectrum of natural foods because there is evidence they contain chemicals that are carcinogenic in rodents? I suspect not.
--You note that young children are of necessity more vulnerable to the ostensible "toxic" effects of these chemicals for a variety of reasons. While this allegation is very commonly employed to manipulate regulators and legislators into banning safe and useful products and chemicals, in fact this assumption is not necessarily true. See the ACSH publication
Are Children More Vulnerable to Environmental Chemicals? (
http://www.acsh.org/publications/pubID.193/pub_detail.asp ).
--You write that "scientists have been worried for years about the health effects of these ubiquitous chemicals." With all due respect, that is not true. The Food and Drug Administration, Consumer Product Safety Commission, and other professional bodies (including a blue ribbon panel on the safety of phthalates chaired by former Surgeon General C. Everett Koop) have concluded that phthalates and BPA in consumer products pose no known risk to human health. This includes the postulated risk to babies who "mouth" toys containing minuscule levels of phthalates--or bottles that might leach roughly the equivalent of 1/1,000th the size of a grain of salt into the liquid.
--You leave your readers with the message that regarding the safety of plastic products and bottles we really "don't know" the risks. But as discussed above, we do have a very firm understanding that these chemicals, as they have been used over the past fifty-plus years, pose no known hazard to human health. Further, you seem comfortable recommending that parents and their children should switch to alternative products--wooden toys, glass bottles, and so-called "natural cleaners." But why do you assume these alternatives are any safer at all? For example, while traditional commercial cleaners have been tested for decades, who has tested "white vinegar, baking soda, and lemon juice" for potential adverse health effects? Do we really want to return to the era of breakable glass baby bottles? Or to the use of less tested products that will be substituted for those you have warned against on the basis of the most meager data? Surely, many of those substitutes will themselves be subject to similar "precautionary" concerns before long.
I fear that you may have misled your readers, causing them needless anxiety about purely hypothetical risks. How many parents, as a result of your article, will misprioritize preventive health measures for their children--worrying about plastic bottles and rubber duckies while neglecting really important measures such as making sure their children use seatbelts, wear protective helmets while biking or rollerblading, and have working smoke detectors--along with other proven ways to reduce the risk of disease and death?
Thank you for your consideration of this feedback on your article. I look forward to your response.
Sincerely,
Dr. Elizabeth M. Whelan
President, ACSH
New York, NY
The American Council on Science and Health is an independent, non-profit consumer education organization concerned with issues related to food, nutrition, chemicals, pharmaceuticals, lifestyle, the environment, and health. ACSH, directed and advised by a consortium of over 350 physicians and scientists, urges Americans to focus their efforts on things that matter--such as maintaining a healthy body weight and not smoking--rather than the countless pieces of nonsensical or trivial health advice that fill the news.
ACSH's Board of Trustees and Founders Circle members can be found at:
http://www.acsh.org/about/pageID.7/default.asp For more information visit
ACSH.org and
HealthFactsandFears.com.
CONTACT: Dr. Elizabeth Whelan 212-362-7044 x235 or whelanE[at]acsh.org
