"There was a minor error in your editorial of AtE Nov 89. You refer to serpentine asbestos as less hazardous than the amphibole, saying that serpentine's 'large, twisting fibers are more easily expelled by the lung.' Serpentine asbestos is indeed less hazardous than amphibole, but it is because the larger fibers don't make it to the lung in the first place. The air passages leading to the lung branch into increasingly smaller passages, and it is in these pas-sages that the serpentine asbestos is caught and expelled up the mucociliary ladder. Once a foreign substance has gotten into the lung, it is no longer expelled. At that point it is attacked by the microphage. It is theorized that the sharp edges of amphibole as-bestos in the lung may physically slice up the macrophage, releas-ing its digestive enzymes . . . which may be the cancer causing agent. In any case, once the particulate has passed through the smallest branches of the air way and reached the lung proper, there is no mechanism to expel it." G.W., Plymouth. Mich.
I am most grateful for the correction. I take it that the small particulates of fly ash that get past the pollution controls in coal-fired plants, said to be "too small to get past the defenses of the lung," enter the lung in the same way.
Meanwhile, it seems that the (brine resistant) asbestos imported from South Africa for insulation in ships was not the only occasion when the dangerous amphibole type was used. The New England Journal of Medicine of 11/2/89 reports that this type of imported asbestos was also used in the filters for Kent cigarettes until 1956, and resulted in an above average incidence of lung cancer and other lung diseases among the workers of the plant. At the time the danger of amphibole asbestos was not yet known, and Kent filters were, in fact, much touted (not only by their manufacturers) as a way to avoid lung cancer
¾an example of how the attempted cure of an incompletely understood problem can produce the very opposite effect.Consider also the ranking of asbestos in the following comparative risks of premature death, tabulated by Harvard U.'s Energy and Environmental Policy Center: smoking 21.9%, motor vehicles 1.6%, frequent flying on airlines .73%, coal mining accidents .44%, indoor radon .4%, lightning 0.003%, asbestos in school buildings, 0.001%.
Responding to the use of radioactive tracers in medicine [AtE Jan 90], P.W. of Medina, Ohio, writes that he had several treatments including thallium heart stress tests. "When trying to exit a nuclear plant . . . I set off the radiation alarm four weeks after the medical procedure. On another occasion, one week after a thal-lium stress test, I set off the alarm of the radiation detector while a number of feet away from the instrument." Since 80% of Th-201 is excreted in 2 days, about 99% in 2 weeks, but 0.01% may be retained for months (writes M. Brucer, M.D.), this shows not how active thallium is, but how sensitive the detectors are.
Must have been the Gruesome Grisly Greenhouse that ruined the Florida citrus crop, haha, but to be fair, a single episode in a structure as complicated as the atmosphere means nothing either way. What is well known, however, is that methane is a "greenhouse gas," surpassed only by CO
2 as an infrared absorber in the atmosphere (about 50% and 25%, respectively). A recent study by the EPA, published Nov. 21, finds that a 50% cut in gas emissions (belches and flatulence) from cattle, buffalo, sheep, goats, as well as those from animal waste would contribute up to 75% of the emission reductions needed, in the fantasies of Reilly's boys, to stabilize atmospheric methane concentrations. They propose doing this by dietary additives to animal feed and (oh horrors!) use of hormones.But why be so half-hearted, why not enforce a worldwide ban of meat and dairy products along the lines of the Montreal Protocol? That's what Jeremy Rifkin suggests, and perhaps it's not a bad idea: I would love to see him drive an air-conditioned luxury car through Ethiopia telling people that they are eating too much meat.
And one more point on plutonium [ATE Dec 89, Jan 90]. "pT, a new classification system for toxic compounds" by T.D. Luckey and B. Venugopal, J. Toxicology & Environm. Health, vol. 2, pp. 633-638 (1977) introduces a universal toxicity measure for chemical, radiological and other poisons. Plutonium citrate turns out to be 10 times more toxic than sodium chloride, and you know what that is, don't you.
Kitchen salt.
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Vol. 17, No. 6
Newsletter: Access to Energy Newsletter Archive Volume: Issues Issue/No.: Vol. 17, No. 6 Date: December 01, 2004 03:29 PM Title: Radishes and watermelons
Copyright © 2004 - Access to Energy Newsletter Archive
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