Wednesday, August 03, 2005


Fears that chemical byproducts resulting from purifying drinking water with chlorine boost the chances that pregnant women will miscarry were not supported by the results of a major new study. If such threats exist at all, which is uncertain, they likely are modest, it concludes. The national study, directed by University of North Carolina at Chapel Hill scientists, contrasts with earlier, less detailed work done in Northern California and published in 1998. That research suggested an association between byproducts known as trihalomethanes and loss of pregnancy. "We think our new work should be an important contribution to policy studies," said principal investigator Dr. David A. Savitz of the UNC School of Public Health. "While it is not the final answer, what we found is largely reassuring relative to what had come before. "The vast majority of the U.S. population is living with these exposures to drinking water byproducts," Savitz said. "If they clearly increased women’s miscarriage rates, that would be a very big, very expensive problem to solve. Reducing exposure would be quite expensive for the water utilities and ultimately their customers." The methods used in the new work make it the most ambitious and sophisticated study ever done on this issue, he said.

Savitz, Cary C. Boshamer distinguished professor and chair of epidemiology, and colleagues released a report on the investigation today. The American Water Works Association Research Foundation, a non-partisan, non-profit research group, sponsored it. Others involved include Dr. Philip C. Singer, professor of environmental sciences and engineering and co-principal investigator, and Drs. Katherine E. Hartmann of obstetrics and gynecology and epidemiology, Amy H. Herring of biostatistics and Howard S. Weinberg of environmental sciences and engineering.

The scientists selected and repeatedly tested three properly functioning water purification facilities, including one with moderate levels of chlorinated disinfection byproducts, one with moderate levels of brominated disinfection byproducts and one with low levels of all disinfection byproducts. None of the utilities was selected because of water quality or health problems. Between December 2000 and April 2004, the team recruited 3,132 women in the three areas who were planning a pregnancy or who had been pregnant for fewer than 12 weeks. They collected extensive information on the volunteers, including their patterns of water use such as drinking and bathing and what later happened with their pregnancies and births. Among tests the women underwent were ultrasound examinations to collect more detailed information about their pregnancies. Researchers then, after adjusting for such factors as age, education, alcohol use and prior pregnancy histories, analyzed the data to see what effects the byproduct compounds might have had on pregnancy loss (miscarriage).

The study uncovered no clear-cut evidence that trihalomethanes harmed women or their developing infants and as a result differed significantly from the Northern California research, Savitz said. The new work did suggest that brominated compounds and total organic halides at normal-range levels in purified drinking water might modestly increase the risk of miscarriages among pregnant women. "These latter findings suggest that we or others should take a closer look at individual and groups of chemicals that might have a negative effect on pregnancy," he said. "I don’t want to downplay those findings and say they were perfectly reassuring because they were not. But overall -- on balance -- I’d say this work moves the evidence in a reassuring direction and should serve to lessen concerns."

Because of the overall negative results, he and his colleagues do not plan to make policy recommendations to water managers and municipalities, he said. If possible, future comparable studies ought to include methods for determining actual exposures to purification byproducts more accurately. "We also looked at exposure to these chemicals in relation to preterm births and did not find an association," Savitz said. "If anything, we found the opposite -- that higher-exposure populations had slightly lower risks. There was some indication, however, that reduced fetal growth might be associated with higher exposure levels."

More here

Half-Baked Alaska

The inexorable drumbeat of climate disaster stories goes on, but no one seems interested in checking the facts. The most recent assault on common sense comes from Alaska. There, Republican senators Ted Stevens and Lisa Murkowski are said to be favoring onerous climate change legislation sponsored by Arizona's John McCain. McCain thinks he can ride global warming all the way to the 2008 presidential nomination, by grabbing the horde of green-leaning California and Pacific Coast delegates that will be off-limits to his Southern competition, Bill Frist (Tennessee) and George Allen (Virginia), who oppose McCain's expensive, ineffective bill.

McCain's bill will do absolutely nothing measurable about global warming for the foreseeable future. It's nicknamed "Kyoto Lite" in Washington, because it is an imitation of the infamous Kyoto Protocol on global warming. Even Al Gore's scientists conceded that, over 50 years, with full participation by every nation involved, the change in global temperature caused by Kyoto would be a teeny thirteen-hundredths of a degree, an amount impossibly small to measure. Given that McCain's staff surely knows this fact, the hidden agenda for his presidential strategy becomes obvious.

McCain's bill only went down 55-43 on Halloween, 2003, so the addition of Alaska's two conservative Republicans is ominously significant, and, as we say in academic circles, counterfactual. Stevens and Murkowski are largely concerned that the Inuit (to old timers, "Eskimo") culture is being damaged by warming. Alaska has been peopled for at least 12,000 years. Within the last 12 millennia, there have been plenty of periods when it was warmer than today, and the culture flourished. Apparently it was too much effort for the Alaska senators' staffers to consult relevant articles in the refereed scientific literature. The most important is a landmark study, "Holocene [post ice-age] thermal maximum in the western Arctic," published last year by 30 eminent scientists whose specialty is past climate. It appeared in the journal Quaternary Science Reviews. The article notes that Alaska averaged three degrees Fahrenheit warmer for 2000 years, from 9,000 to 11,000 years ago. Concurrently, the first civilization radiated forward.

There's another article on Alaskan climate history for the last 2000 years, published by Feng Sheng Hu in the Proceedings of the National Academy of Sciences. It notes that there have been three similarly warm periods in Alaska, from A.D. 0 to 300, 850-1200, and 1800 to present. (Note that humans had no influence on global temperature 200 years ago).

And what of the present? Brian Hartman and Gerd Wendler, of the Alaska-taxpayer-funded Alaska Climate Research Center, have written extensively on this subject. They are particularly interested in something called the "Great Pacific Climate Shift," a sudden and dramatic warming that occurred in a one-year period around 1976. Here's what they have written: When analyzing the total time period from 1951-2001, warming is observed, however the 25-year trend analyses before 1976 (1951-1975) and thereafter (1977-2001) both display cooling.

That's right. The mean Alaskan temperature has been declining for the last quarter-century. All of the warming is determined by a one-year, mysterious "burp" in the temperature of the Pacific Ocean. Is that due to human activity? Search the scientific literature for a computer model of human influence on climate that says it occurs all at once, in a single year. You won't find one reference.

It is a shame that Stevens' and Murkowski's staffers didn't do this rudimentary research. If a few more senators shift their votes on McCain's global warming bill, the nation could be saddled with an expensive piece of legislation that will have no effect on the purported problem it purports to solve. It's a double shame because the known behavior of Alaskan climate is not unusual by historical standards, and even shows a net cooling in the last 25 years, the so-called era of human warming.



Many people would like to be kind to others so Leftists exploit that with their nonsense about equality. Most people want a clean, green environment so Greenies exploit that by inventing all sorts of far-fetched threats to the environment. But for both, the real motive is to promote themselves as wiser and better than everyone else, truth regardless.

Global warming has taken the place of Communism as an absurdity that "liberals" will defend to the death regardless of the evidence showing its folly. Evidence never has mattered to real Leftists

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