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Re: [cdn-nucl-l] A reply to Jerry's questions about DDT
My reaction is that: "I can easily find an equally persuasive case for the
LNT" - if I accept the National Academy of Sciences carefully crafted
disinformation, and their rad-protectionists "peer-reviewed" literature that
misrepresents the science as "true." You would need to do a more complete and
objective review of the science of DDT effects, both biology and population
The government-funded agents will trash sound science as the LNT-apologists do
to pretend the LNT is possible despite the lack of health effects in hundreds
populations that vary over factors of 3 to 100s of background dose levels
(especially natural and medical, plus animal studies, AND both fundamental and
cellular/molecular biology), not least of which is Bernie Cohen's data,
completely confirmed by Ken Bogen's independent analysis of US national lung
cancer vs EPA environmental radon data, and dozens of others (including the
few "good" case-control studies).
Yet NAS produced BEIR VI at EPA direction (using Lubin and many other
agency-funded disinformationist papers) while dismissing Cohen in a couple of
paragraphs and treating his data as a "lone-nut," rather than considering
either the science or the confirmatory data, which they continue to actively
suppress. Don't be gulled by the same kinds of "sources" for DDT.
Regards, Jim Muckerheide
"Dukelow, James S Jr" wrote:
> In response to my posting on the history of the banning of DDT in the US,
> Jerry Cuttler asked the questions:
> 1) Did reputable scientist establish whether proper use of DDT actually causes
> significant harm to birds eggs, or is this a myth?
> 2) Does DDT last forever? If it reacts with mosquitos, something must break it
> 3) How much DDT accumulates in species at the top of the food chain? At what
> concentrations does it plateau? Is this concentration significantly harmful?
> 4) Which chemicals do we currently spray in our towns (and nearby marshes)
> when there is a severe mosquito problem?
> These are worthy questions, which I'll try to answer. I apologize for the
> delay, but it took me awhile to find my DDT files (right next to my office
> chair in a mislabeled box).
> Easiest first. In several recent cases of spraying to control mosquitos and
> med flies, malathion has been used. It is one of the least toxic of the
> organophosphate pesticides, some of which are closely related to nerve gas and
> exceedingly toxic. Use of malathion, most recently in NY City to help combat
> West Nile disease has usually been opposed by at least some environmental and
> neighborhood groups. Milloy's FoxNews piece mentions a couple of other
> pesticides used in NY that I am not familar with.
> Regarding the other questions, a bit of background first. I first got
> interested in this issue a few years ago when a RISKANAL subscriber posted
> what I considered a scurillous attack on Rachel Carson, essentially accusing
> her of being a mega-murderer -- arguing that continued use of DDT would have
> prevented millions of deaths. I didn't actually know as much about the issues
> as I at first thought I did, so I set out to research the history of the
> banning of DDT. I mostly searched the news and editorial columns of Science
> and Nature and Chemical & Engineering Weekly (published by the American
> Chemical Society) and research reports in Science and Nature. I considered
> them to be mostly reliable sources and our poor desert library had runs of
> all three going back into the 60s. It is fair to say that Nature and C&EW
> were strongly opposed editorially to the decision to ban DDT, both before and
> after the decision. I read parts of Silent Spring and parts of Since Silent
> Spring (written by Frank Graham, Jr. and strongly supportive of Carson). I
> read about the global campaign in the 50's and 60's to eradicate malaria, a
> campaign built around DDT, reading the accounts in Laurie Garrett's book on
> emerging diseases, The Coming Plague, and in Robert Desowitz' book, The
> Malaria Capers. I was able to chase down a couple of the blue ribbon
> commission reports written in the late 60's. The first was Man's Impact on
> the Global Environment (MIT Press, 1970). The roughly 140 participants were
> heavily loaded with MIT and Harvard faculty. Names I recognized include Hans
> Panofsky, George Rathjens, Reid Bryson, Roger Revelle, and Herbert Simon. The
> workgroup on Ecological Effects looked in some detail at the impact of DDT and
> other pesticides on the marine environment. The other major commission report
> I looked at was the Mrak commission report, from which I quoted at some length
> in my earlier posting. An interesting and relatively balanced account of the
> DDT issues, written by a defender of DDT, is the chapter "Is DDT a
> disreputable chemical?" in Aaron Wildavsky's book, But Is It True?"
> The picture I got from all of this was that DDT had a significant impact on
> reproduction of some species of birds, including many raptors and other birds
> at the top of the food chain. There is a lot of species to species variation.
> Indeed, Graham points out [p. 130] that although bald eagle, osprey, and
> peregrine falcon eggshells are drastically thinned by DDT, golden eagles, red-
> tailed hawks, and great horned owls are not affected (although he notes
> elsewhere in the book that golden eagle populations in Western Scotland
> crashed during the years that dieldrin was used as a sheep dip, with sheep
> carrion being a major part of the golden eagle diet in the West). The golden
> eagle population in Eastern Scotland had a different diet and was not
> affected. Chickens and a number of other birds that can be described as not
> quite at the top of the food chain were unaffected. The Mrak Commission notes
> [p. 179] that DDT causes eggshell thinning in ducks and falcons, but not in
> pheasant and quail. Cats seem to be particularly sensitive. A nice exercise
> for the reader is to do an Internet search on "Bolivian cats". Even sources
> essentially opposed to the banning of DDT (Nature, C&EN, and Wildavsky,for
> example) agree that DDT had a significant reproductive impact on many species
> of birds.
> In a Nature news article written during the run-up to Ruckelshaus' decision to
> ban DDT, the Nature reporter wrote: "But on the other hand, four government
> committees which have studied DDT between 1963 and 1969 all recommended phasing
> out it use and the Mark [sic] Commission recommended elimination by December
> 1971 of all uses of DDT not essential to public health." (Nature, v. 232, p.
> DDT doesn't last forever. A paper by Woodwell, Craig, and Johnson, three
> scientists at Brookhaven (Science, v. 174, pp. 1101-1107, 10 Dec 1971)
> attempts, with a lovely series of back of the envelope calculations and simple
> linear box-and-arrow models, to estimate the flow of DDT through the
> environment to its ultimate resting place, the deep ocean abyss. They
> establish that the main reservoirs are soil, the atmosphere, the ocean mixing
> layer, and the abyss. The mean time of residency of DDT in these reservoirs
> is only 3 to 5 years in each reservoir. The small fraction of DDT that enters
> the biosphere, migrates to fat deposits, where its half life might be on the
> order of 10-20 years. The corollary of DDT's persistence in the environment
> is relatively low toxicity and chemical reactivity, but again with lots of
> species to species variation. One of the more interesting parts of Woodwell,
> et al. is Table 2, which provides estimates of biomass (in billions of metric
> tons): land plants = 1850, ocean plants = 3, feral mammals = 0.009, domestic
> mammals = 0.17, humans = 0.3, fish = 0.65, ocean mammals = 0.055, other ocean
> animals = 3. They assume values of 1 ppm of DDT for continental shelf algae,
> land animals, fish, and ocean mammals. They assume 0.1 ppm of DDT in
> agricultural products. With these assumptions the major living reservoirs for
> DDT are agricultural plants, algae, domestic mammals and man, fish, and other
> ocean animals.
> The equilibrium amount of DDT in species at the top of the food chain varies a
> lot and its effect varies a lot, with some species tolerating levels that will
> exterminate other species. Wildavsky points out that the equilibrium level in
> the top level predators will depend on the extent to which all of the plants
> and animals down through that food chain accumulate or excrete DDT. One
> species in the food chain that is able to eliminate most of the DDT it
> consumes will result in low levels higher in the chain.
> That said, here are some values. Measurements at Clear Lake in California
> showed 0.02 ppm of DDD (a compound closely related to DDT and its breakdown
> produce DDE) in the water, 5 ppm in microscopic plants and animals, 2000 ppm
> in fish, and 1600 ppm in grebes that fed on the fish. The DDT mystification
> campaign makes a point of the fact that the concentration in grebes was lower
> than in the fish they preyed on, without pointing out that 1600 ppm was enough
> to kill the grebes.
> The Mrak Commission [p. 208-9] notes that oysters will concentrate DDT by a
> factor of 70,000, that 24 hour exposure of blue crabs to 0.5 ppm DDT in water
> killed 50% of the crabs, that 72 hour exposure of crab larvae to 5 ppb (Yes,
> that's ppb)
> causes 100% mortality, and that lake trout eggs having 5 ppm DDT had 100%
> mortality. A Canadian trout hatchery found that all 16 commercial dry fish
> foods it tested for possible use contained DDT and its breakdown products and
> that some of them caused 30% to 90% mortality to fry and fingerlings.
> American sparrow hawks, experimentally fed a mixture of 0.28 ppm dieldrin and
> 1.4 ppm DDT, levels consistent with those found in raptor food items in the
> field, suffered reduced reproductive success.
> Nature, in commenting editorially (and negatively) on Ruckelshaus' decision to
> ban DDT in the US, said "To be sure, there are some places -- Lake Michigan is
> a conspicuous example -- where the residues of DDT are already so great that
> commercial fishing has been made unproductive" and "This is why most students
> of the problem have come to the conclusion that the chief victims of DDT so
> far are likely to be birds, both predatory birds such as eagles and falcons
> and fish-eating birds, especially the pelicans off the coast of California.
> Over the years, a great deal of evidence has accumulated to suggest that eggs
> containing large quantities of DDT, and which are presumably laid by birds
> with a similar disability, have thinner shells and are therefore less viable
> that they would normally be. ... it is probably wise on balance to suppose
> that DDT is actually bad for individual birds."
> Finally, in the same editorial (Nature, v. 237, pp. 417-418, 23 June 1972),
> the editor of Nature wrote, "After all, much of the present fuss would not
> have arisen, and pesticide residues would not have accumulated to the extent
> they have in human fat, if the agricultural uses of the persistent pesticides
> in the past twenty years had been more prudent." This bears on the phrase
> "proper use" in Jerry's first question and on the current issue of whether DDT
> and eleven other persistent chemicals should be banned worldwide or whether
> DDT should be exempted, at least temporarily, because of its benefits in
> malaria prevention.
> An interesting sidelight: Rachel Carson and William Ruckelshaus are the
> villains of Milloy's op-ed piece and in similar attacks on the historical
> record. But Ruckelshaus, the Administrator of the EPA, had a boss, Richard
> Nixon. It is naive in the extreme to assume that Ruckelshaus banned DDT
> without Nixon's concurrence, particularly since the banning was a slap in the
> face of Jamie Whitten, the chairman of the House Agriculture Committee, a
> stauch defender of the use of DDT on cotton, the author of a book in praise of
> pesticides, and the gatekeeper for the Department of Agriculture budget each
> year. Not a peep about what a bad guy Richard Nixon was for approving the
> Another sidelight: Carson proposed some alternatives to the use of DDT. The
> first mentioned was biological control and her primary example of successful
> biological control was the extermination of the screw worm in Curacao and
> Florida in the 50's by means of the release to the environment of millions of
> male screw worm flies that had been sterilized by irradiation. She was
> probably too optimistic about the general applicability of the technique.
> Best regards.
> Jim Dukelow
> Pacific Northwest National Laboratory
> Richland, WA
> These comments are mine and have not been reviewed and/or approved by my
> management or by the U.S. Department of Energy.
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