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Washington Post (pg. B1), Dec. 4, 2006 [Printer-friendly version]<http://www.precauti on.org/lib/ 06/prn_human- pollutant_ ties.061204. htm> INQUIRY TURNS TO HUMANS ON POLLUTANT, HORMONE TIE Evidence Such as Eggs In Male Fish Spurs Push By David A. Fahrenthold Growing evidence that chemicals in the environment can interfere withanimals' hormone systems -- including the discovery that male Potomac Riverfish are growing eggs -- has focused the attention of environmentalists andscientists on a new question: Are humans also at risk? A decade ago, thevery idea that pollutants could interfere with a body's chemical messageswas near the fringes of science. But now, it is an urgent topic forlawmakers and researchers around the world, and especially in the Washingtonarea. In recent years, researchers have linked some common chemicals totroubling changes in laboratory rodents and wild animals, includingreproductive defects, immune-system alterations and obesity.============ ========= ========= ========= ========= ======== Sidebar In recentyears, scientists and lawmakers have become more concerned about pollutantsin the environment that appear to interfere with natural hormone systems. Afew of the most widely known examples: Bisphenol A -- Description: Buildingblock for plastics. Found in: Clear plastic bottles such as those used byhikers and infants, as well as resins used to line food and drink cans.Results of research: In animals, low doses have been linked to low spermproduction, altered growth and behavioral changes. The chemical industrysays other studies show that the chemical is safe. Phthalates --Description: Chemical

additives that increase plastic's flexibility. Foundin: Flexible vinyl toys, wallpaper and electronic devices. Results ofresearch: In animals, these chemicals affect the functioning of male brainsand sex organs. In humans, one recent study found a correlation betweenmothers' exposure and subtle developmental changes in baby boys. Thechemical industry says that there is no proof that human health is at risk.Treated sewage -- Description: Can include natural hormones excreted byhumans and artifi cial hormones such as those in birth-control pills. Foundin: Rivers and streams where treated sewage is released, including thePotomac River. Results of research: Blamed for causing fi sh in severalstreams to be "intersex," with both male and female characteristics.============ ========= ========= ========= ========= ======== For now, noconnections to human ailments have been proved. But some studies haveprovided hints that people

might be affected by crossed hormones, andactivists wonder if this kind of pollution could contribute to diabetes,birth defects and infertility. "There's a lot of concern that a lot ofchemicals to which we are exposed routinely, and without our knowledge, areinterfering with the way hormones work," said R. Thomas Zoeller, a professorof biology at the University of Massachusetts at Amherst. The MetropolitanWashington Council of Governments is planning to host a public forum abouthormone-disrupting pollution this spring. U.S. Reps. James P. Moran Jr.(D-Va.) and Chris Van Hollen (D-Md.) have said they plan to press theEnvironmental Protection Agency about its failure to develop a program totest chemicals for hormonelike effects, as ordered by Congress in 1996. Theidea that natural hormone messages can be tampered with is not new; fordecades, women using

birth-control pills have been counting on a man-madechemical to do just that. But the current concern is much wider: Some fearthat modern chemistry might have unwittingly created other compounds withhormonelike effects and that they might have spread widely around the globe.In the past few years, scientists working with animals have found potentialproblems with several pollutants, among them rocket-fuel components,pesticides and additives to soap. Among the most heavily researched: **Phthalates, a family of additives used to make vinyl plastic flexible andprevent perfume from evaporating, have been linked to lower sperm counts andother sexual problems in male rats, as well as to heightened allergicreactions in the animals. Chemical industry officials have said that thesetests used unrealistically high doses and that the results are not likely totranslate to humans. ** Bisphenol A, used as a building block for hardplastic

goods like bottles and as a resin to line food cans, has beenconnected in some experiments to abnormal sexual development in male labrodents, as well as a predilection for obesity. Officials from the chemicaland pesticide industries have vigorously criticized these results, sayingthat other studies have shown the chemical to be harmless. ** Treatedsewage, which carries human estrogen and birth-control pill componentsexcreted in waste, has been linked to "feminized" male fish in waters aroundthe world. In the St. Lawrence River in Canada, a recent study found that athird of male minnows had female characteristics. Another example might bethe Potomac, though the cause of its problems has not been officiallypinpointed. The EPA and sewage-plant officials have said they are working onways to better clean the wastewater. The study of endocrine disruptors

beganin the late 1980s and early 1990s, with scientists struggling to add up suchoddities as male birds with female organs in the Great Lakes and sexualdefects in Florida alligators. They eventually found that some chemicalswere turning on hormone switches in the body's endocrine system that triggerbiological processes. Others blocked the switches so natural hormonescouldn't get through. That revelation meant that a pollutant could beharmful even if it wasn't poisonous and didn't cause cancer. Even smalldoses could cause major damage, if they came at a key time when hormoneswere guiding pregnancy or early development. "We have to ask differentquestions," said John Peterson Myers, an activist and former scientist basedin Charlottesville. He joined with scientist Theo Colborn and writer

DianneDumanoski to write a book laying out their concerns, 1996's "Our StolenFuture." Today, despite the wealth of studies in animals, the implicationsfor human health are unclear. One of the most dramatic studies examined thesons of mothers whose bodies contained phthalates. It found no major birthdefects but did show that the higher the phthalate level, the greater chancethat the boys' bodies would show subtle signs of being "undermasculinized, "according to researcher Shanna Swan, director of the Center for ReproductiveEpidemiology at the University of Rochester. Still, that falls well short ofa smoking gun: Humans are not laboratory rats, so scientists say it isexceedingly hard to craft a study that shows a particular chemical caused aparticular problem, and not genetics, diet or some other factor. "They'renowhere near cause-and-effect, " L. Earl

Gray Jr., a senior researchbiologist at the EPA, said of human studies. "We're showing correlations andassociations" between pollutants and human health effects, he said, but noindisputable sign that one causes the other. Officials from the chemical andpesticide industries have vigorously defended their products, saying theysee no reason for concern about products in the environment interfering withhuman hormones. Some scientists have also pointed out that human diets havealways included some estrogen-like compounds: They occur naturally in wineand soy-based products, for example. Stephen H. Safe, a professor ofveterinary physiology and pharmacology at Texas A & M University, said thatoverall, despite our poor diets, "what does the data say about our health inthis country? We're living longer... You know, where are these endocrinethreats?" Still,

concerns that human health might be in danger have led torecent bans on certain phthalates in young children's toys imposed by theEuropean Union and the City of San Francisco. Activists in the United Stateshave attacked the EPA for what they believe is a delayed response to theproblem. The agency has defended itself by saying that it has spent millionson other research programs looking at ways to identify and limit endocrinedisruptors and that it hopes to begin the long-delayed chemical testingprogram next year. Some activists fear that damage is already being done.They caution avoiding plastic baby bottles, which could contain bisphenol A,and reducing consumption of animal fat, where some environmental pollutantscan concentrate. "I feel terrible because we haven't moved on this

faster,"said Colborn, the activist who has served as an unofficial leader amongendocrine-disruptor researchers. "This is a transgenerational problem thatis undermining the integrity of humans." But Paul Foster, an official whoevaluates risks to human reproduction at the National Institute ofEnvironmental Health Sciences, said it was hard to give useful advice atthis point because the chemicals being investigated are so ubiquitous."There's very little that they can do," said Foster, whose agency is part ofthe National Institutes of Health. "That's why you can't be too alarmistabout it, because you can't stop people living." Copyright 2006 TheWashington Post Company Ellen LaFleche-Christian Lilac Hill Homestead / Vermont http://tinyurl.com/lpfaf Do You ?