LAS VEGAS – It can kill crops and destroy buildings. It’s used as an industrial coolant and is present in all cancer cells. Yet, it’s ending up in our food. What is it?
If you guessed "water," you’re ahead of scores of people who have signed petitions to ban "dihydrogen monoxide," a tongue-in-cheek name for H2O. Many such hoaxes, urban legends, and fallacies are circulating via Web sites, e-mail, television news reports, and ordinary conversation, said Dr. Cyrus Rangan, director of the Bureau of Toxicology and Environmental Assessment at the Los Angeles Department of Public Health.
He dispelled the following common myths in a presentation at a pediatric update sponsored by the American Academy of Pediatrics California District 9.
• Vaccination autism. In some cases, the origins of a myth are difficult to trace, while in others, key events are known. In this case, a 1998 study published in Lancet linked autism to vaccinations. Many studies since have refuted the link, and the journal retracted the article in February 2010. "I think it’s going to take an entire generation or more before the scarring from this incident heals," Dr. Rangan said.
• Poisonous poinsettia. In 1919, a 2-year-old child died after eating a poinsettia leaf, leading to years of unfounded concern, Dr. Rangan said. In 1975, the U.S. Consumer Product Safety Commission petitioned to include warning labels with the sale of the plant. Yet no reports of deaths attributed to a poinsettia have been recorded on Medline. In a 1980 investigation, 46 rats remained healthy on a 1-week diet of poinsettia (Clin. Toxicol. 1980;16:167-73).
• Blinding sunscreen. What should you do if some sunscreen gets into your child’s eyes? "I called the poison control center. They told me to RUSH Zack to the ER NOW!!" read one hyperbolic 1998 chain e-mail that Dr. Rangan quoted. "MANY kids each year lose their sight to waterproof sunscreen," it continued. But again, Medline has no record of any cases of blindness caused by sunscreen, either waterproof or regular.
• Microwaved plastic. A high school science experiment, apparently combined with speculation by a chemist interviewed on Hawaiian television, resulted in a 2002 chain e-mail warning against the possibility of dioxins leaching from plastic wrap into food when microwaved. "I would never say every urban legend is completely without merit," Dr. Rangan said. In fact, the plastic can release trace amounts of diethylhexyl adipate (DEHA) in excess of U.S. Food and Drug Administration standards, but it is unlikely to do this in typical microwave heating. And no human health effects have been shown. "FDA standards are not toxicity standards," Dr. Rangan said.
• Noodle wax. Another 2000 chain e-mail warned of toxic wax in foam containers for instant noodles, and even mentioned the death of an unfortunate noodle eater. But polystyrene noodle containers are not lined with wax, and no waxes have been linked to hepatotoxicity or deaths in the literature on Medline, Dr. Rangan said.
• Lipstick lead. A 2003 e-mail listed brand-name cosmetics containing lead. "Do NOT kiss your children, while wearing lipstick!!!!" it said. But the FDA tightly regulates lead in cosmetics and there are no published studies on lead in excess of FDA standards in any cosmetics, nor any cases of human exposure to lead from lipstick cited in the literature on Medline.
• Mercury fillings. "Some 80% of the population will experience only a slight change of their immune system which will result in three colds per winter instead of only two," said a 1985 report that sounded particularly convincing in its specificity about the dangers of amalgam restorations. In fact, Dr. Rangan said, there are no cases documented on Medline of immune or respiratory illnesses linked to dental amalgam.
• Lead glassware. In February 2005, a television program carried a report of high lead content in painted designs on glasses and dinner plates. "The lead you find can actually be quite alarming," Dr. Rangan said. "But we don’t scrape stuff off a glass, then drink it." The correct test for lead should have been to dunk the glassware in acetic acid to see how much lead leached off. The television program had performed that test and found that the level was safe, but chose to report the more dramatic, less relevant information about the contents of lead in scraped-off paint, Dr. Rangan said.
• Urine Luck. Not so much a myth as a scam, this Internet-marketed product contains pyridinium chlorochromate, which by dissociation yields chromium VI. Chromium VI can mask tetrahydrocannabinol (THC), the active ingredient of marijuana, in urine samples, Dr. Rangan said. However, employers now know to check for pyridinium chlorochromate in urine.