As I suspected, there aren't too many major universities quoting the retractions of what was eventually branded "Junk Science".
Back in the early '70's, it was considered political suicide to suggest that DDT was safe. Even after the science community had "peer reviewed" the egg shell studies & found them to be false. DDT had an impact on calcium movement. It very slightly improved it! However unsettling & contradictory this sounds, the subject was too hot for polls & salaried researchers to bet their farms on.
I probably didn't include enough detail with respect to avian dietary needs. True enough, some of the birds that were impacted aren't insect feeders. But the birds of prey (like Falcons & Eagles) do feed on other insect feeders. But then they were also being hunted for sport up to that time. I know of one guide who still offers illegal eagle hunts. I don't get it, but someone must.
Very subtle changes in a captive birds diet can have serious implications with respect to phoshorous & calcium absorbtion rates. This anyone can find reference to. GOOGLE Search "poulty diet eggshell crack phosphorous calcium" & see how many .edus & .govs there are.
Based on what is now known, IT IS MY OPINION, that the reduction in insects in the "total food chain" led to the very small changes in the birds diets. Those very small changes make very large shell thickness alterations.
Also, here in America, there was plenty of newer Patented (read exclusive to one manufacturer) insecticides debutting in the wake of DDT. So don't think for a second that there would be an effort to halt the domestic death of DDT. Americans could easily afford to pay for these new insecticides. Malathion is the next cheapest insecticide. At this time, it's costs double what DDT does. Why then would anyone on the supply side argue with DDT's demise?
Here is a link that reference .edu's to the extent they can. But remember, .edu's get lots of money from & harbor quite a few Sierra Clubbers.
I wasn't going to put this up because it looks a little sleazy, like a tabloid or something.
But the referances are all there & the ones I've checked seem ligit. I'll stick with checking ref's as time allows. But not today. My first appt is in 45 minutes.
Sorry, Steve. The junkscience.com info is just snippets of info. You can just make any idea seem real by just quoting a sentence or two. Best one I ever saw was in mid-50s, it was thought that President Eisenhower might have a brain tumor. Day after testing, our newspaper headline read "Test Shows Ike Has No Brain Tumor." One of the guys in school cut out that headline, so it read "Test Shows Ike Has No Brain." LOL! There it was in a newspaper headline!
And Dr. Edwards seems to be one of very few who try to sanctify DDT. He may refute one test, but how about the all the others? If the enemy has 100 soldiers, and you shoot one, did you win the battle?
Just did a Google for "eagle" & "DDT": 12,000 some hits. Don't really have time to read them all, but I would venture that all except a couple of dozen will affirm that DDT was a problem for eagle eggs. And of that couple dozen, they are probably mostly reference to Dr. Edwards arguements.
Besides that, you must look at history in perspective of the times in which it happened. Would be kind if silly to ask why the Romans didn't nuke the Huns, no? There were many discoveries of negative effects of commonly used chemicals and products happening in the 30s to the 60s. A number of chemicals used in manufacturing were found to be killing or deforming workers by building up in their bodies. Then there was mercury, chromium, asbestos, and others I can't think of right now. There was a very real concern for persistent chemicals, and when DDT (DDE) was found to be very persistent, it was only a matter of time before it and other organochlorines would be done away with.
The thinking was: even if we can't prove today that it is some drastic problem, what if we find it is a problem in the future when the earth is laden with millions or billions of tons of it. One of my customers has an asbestos roof - yep, asbestos shingles. If it had to be replaced today, it would cost 20-30 grand - most of that for safe removal & disposal of asbestos. That type of potential problem led to the demise of DDT. Some people may have fanagled data, probably on both sides of the fence. It's done with. To state today that "millions die because we can't use DDT" is just an emotional rant.
A teacher I had 15 years ago put it the best. After describing the lives saved during WWII in Italy by the Allies use of DDT on liberated Italian villagers, he asked "Was DDT bad to these people? Of course not. But, we must put it into perspective, and recognize DDT as an important human learning experience."
It's not about liberalism or reactionaries, it's just a little common sense.
North central Indiana
<a href="http://members.aol.com/groundkprs/Entry/Educate.html">Learn About Turfgrass</a>
I am going to concede defeat.
Not because I believe the findings as they are most commonly presented. (against my theory) But because the studies themselves have not been done under controlled conditions. Neither the ones that support my theory, nor the ones that contradict me. I therefore am not comfortable sighting any of the sources in my own defense.
I feel the best studies are those done with caged birds that have been fed the same manufactured diet for several generations. The diet & the birds would then both be studied.
As I've previously indicated, I know avain breeders (parrots in one case, falcons the other). Both have trouble moderating dietary needs with respect to eggshell quality.
Other factors that bird specialists must be aware of include noise. Loud noises have a greater impact than diet in SOME SPECIES.
Not one of the DDT studies that I've reviewed included noise monitoring data nor significant diet data.
That's why I only believe the studies that came from the Poultry industry. Poultry farms don't move about into & out of established airline fight-plans like field researchers do.
I agree that JunkScience.com is rather tabloid like. That's why I hesitated to post. However, Steve Milloy includes his references. I think you referred to them as "snippets". Actually, they are ABSTRACTS. But like a politician, he only presents those abstracts that support his argument.
I've included abstracts below that are the accepted means of summarizing scientific research findings & then presenting them for peer review. Independant researchers use the titles & dates to obtain actual copies of the published material and attempt to duplicate the results.
I think the trouble with DDT research is both actual & political. Some researchers have used the best test equipment available & yet we no the gas chromatographer is not fool proof for detecting DDT. None of the field research has included a dietary standard because it is nearly impossible to control a wild birds diet.
I learned a lot researching this subject. I'm very glad that GOOGLE is available for free. I think that "Google Hits" reveal a lot about people. Check this out; if you type in the following words, google yeilds the following hits.
My summary is that Racel made DDT (& GreenPeace) bigger than herself but she is fading slowly. People are more interested in fiction than they are truth.
The only factual points that I believe we can take home are the following:
1 DDT was removed from the market for political reasons more than scientific ones.
2 DDT does have an effect on calcium during egg formation. To which I was in error.
3 The calcium/egg/ddt relationship appears to vary by species from zero to significant. DDT may increase some captive birds eggshells thickness. Probably with little or no benefit or detriment.
4 Only the poultry industry was able to control dietary intake yet their findings were squelched.
5 DDT saved MILLIONS of Human Beings from infectious disease.
6 DDT may have reduced some populations of certain bird species during which time other flourished.
7 Rachel Carson changed the world in ways she may not have intended.
8 Early bird count studies might have been flawed, but on the surface, made Rachel look like the liar she was.
9 We probably shouldn't go back to DDT in this country since we're better of now than before.
10 A better/safer/cheaper Mosquito specific insecticide is sorely needed to reduce mortalitly in certain countries, especially those on the continent of Africa.
11 There may have been many other factors that affected certain bird populations but all were blamed on DDT because there was profit to be made on it's demise.
I've gotta run for now,
PUBLISHED WORKS AGAINST EGGESHELL THINNING
Source: Fed. Proc. Fed. Am. Soc. Exp. Biol. 36(6): 1888-1893; 1977.(9 references)
PESTAB. In well-controlled experiments using white leghorn chickens and Japanese
quail, dietary polychlorinated biphyenyls (PCBs), DDT and related compounds
produced no detrimental effects on eggshell quality. A drastic reduction in hatchability
of chicks occurred with 10-20 ppm PCBs, but no detrimental effects on eggshell quality,
egg production or hatachability were found with** Clipped for length** wever, at levels providing 10 or 20 mg Hg/kg of diet, severely affected all of these
parameters. Even though the present experiments demonstrate that neither DDT nor
PCBs has any effect on eggshell quality in chickens and Japanese quail, they may
cause thinning of eggshells in other species. Controlled experiments are lacking.
Eagles, ospreys and pelicans all consume fish which in many areas of the world are
known to contain methyl mercury. The thinning of eggshells in these species in the wild
may have been due, at least in part, to environmental contamination with
methylmercury rather than DDT, DDE or PCBs, as has been claimed. (Author abstract
Switzer B C
Source: Nature (London); 240(5377): 162-163; 1972 ; (REF:5)
HAPAB A Letter-to-the-Editor disputes the claim that eggshell thinning in brown
pelicans is directly related to DDE residues, (see Abstract no. 72-0972). The statistical
correlation used to show a cause and effect relationship was obtained by grouping
unrelated populations and subspecies, and no evidence was presented to eliminate the
many other factors which could explain the differences between species, times, and
populations. A bias may have been inherent in the museum and oologist collections in
the years before 1947, favoring larger, thicker, unfractured eggs. Evidence from earlier
experimental studies used to support the conclusion that DDE is responsible for
eggshell thinning is rejected since some control birds in the study under consideration
had thinner shells than the DDE-treated birds.
Entry Month: December, 1973
THIS IS INTERESTING. __________________________
Source: Diss. Abstr. Int.34(10): 5254B; 1974
PESTAB Brown pelican (Pelicanus occidentalis) eggs collected from areas of high and
low levels of environmental DDT contamination (10. 5 ppm and LT 0. 02 ppm in prey
species) were examined for aberrations in eggshell structure using the scanning
electron microscope (SEM). Additionally, eggshells of coturnix quail (Coturnix coturnix)
exposed to three levels of DDT (5, 25, and 225 ppm technical DDT in diet) were
examined. Measurements of eggshell structure are reported. A comparison of brown
pelican and coturnix structure concluded with the following results: that brown pelican
and coturnix quail eggshells were shown to differ ordinally but in most characteristics
were strikingly similar; that ''normal'' eggshells of brown pelicans and coturnix quail
were shown to exhibit average shell layer thicknesses which were essentially constant
between eggs of the same speciesöin short, providing a potentially valuable
comparative basis for future studies; that brown pelicans and coturnix quail exposed to
similar levels of DDT in prey species and experimental diets produced eggshells with
similar structural aberrations; that premature termination of the egg was not the cause
of eggshell thinning in brown pelicans or coturnix quail; that DDT causes a disruption of
mucoprotein deposition in eggshell membranes; and that DDT disrupts the formation of
''foundation stones'' which are believed to control subsequent calcareous deposition in
avian species. (Author abstract by permission. Copies of the thesis are available from
University Microfilms, Order No. 74-8507. )
FOR EGGSHELL THINNING
Author Address: Comp. Pathol. Surg. Branch, Vet. Med. Div., Biomed Lab., Chem. Syst. Lab.,
Aberdeen Prov. Ground, MD
Source: J. Toxicol. Environ. Health 3(4): 699-704 1977 (23 References)
PESTAB. The effect of chronic exposure to DDT on the activity of eggshell gland
Ca-ATPase in vivo was studied, and the relation of changes in enzyme activity to
parameters of eggshell quality was determined. Adult mallard ducks were fed a diet
containing 50 ppm DDT for 6 months. This ingestion resulted in production of eggshells
that were significantly thinner and lighter than those of controls. Total calcium of
thinned eggshells was also reduced. However, calcium per gram of eggshell was not
changed, indicating that other eggshell constituents were not incorporated as well.
Calcium adenosine triphosphatase activity in the microsomal fraction of eggshell gland
epithelium was assayed in control and DDT-fed ducks. Enzyme activity in DDT-fed
ducks was reduced to 65% of control. Since Ca-ATPase is associated with calcium
transport, it is suggested that enzyme inhibition may be respo
clipped to fit--
No, Steve, not defeat, just learning. Exposure to information. Expanding your perspective. Making Jim really think - that's an accomplishment.
Everyone should have to spend a year on a debate team. You go into a competition knowing the topic, but not which side you are to argue. Makes you learn all about the subject, and shut off your personal feelings. Great way to really learn a subject. And it's neat to win when you are arguing the side you oppose in your feelings.
The problem with research as it is done today is that someone sets out to prove his theory, and does a research project on it. And someone who believes the opposite will do a project to prove his ideas. So the projects are corrupted from the start, because the results are to meet the ideas of the researcher. Not too much done anywhere where people look at something with no bias to see what happens.
So decisions come down to what information is available to the decision maker, whether it is you today on a client's project, or Ruckelshaus on DDT in the 70s. And of course the decision can be swayed by the decision makers' feelings or politics. And it's not just the information, but how it is presented.
Always remember, what you see on a website, in a book, on TV, in the newspaper, in a police report, etc., is just information, not fact. Facts are hard to discern in today's world. I can pretty much say it is a fact that grass grows, and needs to be cut, but I'll bet you could find people to argue about that. LOL.
Ever want to learn more about a topic you really believe in? Get into a group of people who believe the same way, and argue against them!! Right, try to argue against your beliefs; can only do that if you really know & understand the cons against you. And when you take the opposite position in the group who are vehemently set, you will, almost always, learn something new to confirm your beliefs.
I was not trying to defeat you, just injecting more information for others who might be following the thread. And now, what does Jim really believe about DDT ? ? ?
Does it really matter to you?
It shouldn't! You've got information from all over, Jim and tremor and others. You have to decide for yourself, based in the information you have. If it's not enough info, you can just forget about it, or search to be better informed.
North central Indiana
<a href="http://members.aol.com/groundkprs/Entry/Educate.html">Learn About Turfgrass</a>
You bring up valid points.
Thus the so called "double blind study" was born to prevent researchers from letting their hypothosis from affecting the conclusion. Which is difficult to do. Most folks can't be trusted to check their opinion at the laboratory door. That discipline is too extreme.
I only debate to hone skills. It's also a semi competetive sport! This is the value in this website. If all we ever did was answer questions & agree with one another, we'd never move ahead intellectually.
It sounds like you were on the debate team. I was too, but not long enough. I didn't realize the value in debate until more recently. Debate is truely the best way to gain a better handle on any subject. The internet makes drilling down into the subject matter even easier than in the past. We used to need access to a serious library to get this information. In our field, usually more than one. At one point, I was visiting four! The key to internet research is to recognize that most of us have an agenda.
Networking with our peers used to take longer too. In the past we waited for trade shows or other events to access each other. There was the phone too, but that can be a hurried affair. This forum allows each of us to use our own "down-time" whether it matches someone elses or not.
Most LCO's are hesitant to share their successes with other local LCO's for fear that their hard gained knowlege will be used competetively against them in the field of business. Here we find several other folks that may be thousands of miles away from each other engaged in debate. That distance offers comfort.
DDT, because of it's economy, should be reexamined. Without the benefit of controlled studies by non-financially motivated parties, I feel the rearch has been of little use. Field studies could never have been consistant. Some watershed areas would have seen raptor food sources tainted with DDT in the fishes fat. Other areas would not have been as affected.
Regional distribution of prey & predator played a large roll, but was never mentioned.
Land terrain & topographical relief was ignored.
The noise issue was rarely addressed.
Records of DDT application rates, volume, & method of application probably don't exist for reference.
The method of testing for DDT & it's derivatives & like compounds are still very suspect in all but the best hands.
To this very day, the folks charged with the task of collecting field material & dispensing with tests are, in my opinion, suspect. College interns & overworked/underpaid public service employees are rarely motivated by anything more than sensationalizing an issue to gain a name for themselves. It's the rise to fame, glory, & wealth that many are concerned with. Controversy is a means of attachment to the politically influencial who are the able to assist in career furtherence.
The labs & equipment they use is usually old & inferior. The best equipment is owned by the large commercial entities. Like our own chemical vendors. Since DDT's patent is long gone, there would be no financial gain in proving or disproving it's safety.
I don't feel defeated. But my subject, in this case, is. And so is a portion of "the system".
Capitalism is a wonderful thing. Just so long as a patent keeps people/companies motivated enough to protect the tools of interest. But charity is too expensive in this case.
DDT has been in constant use for almost 60 years. In this country, it bears the mantle built by hunters, sulfurdioxide emissions from coal burning, mass population explosions, urban sprawl, the developement of the mass transit system including interstate highways, railroads, & the boon of commercial air traffic, & possibly the avdent of the automobile. The impact we have had on this country in the past century upset the ecosystem. Birds loss of native habitat has been extensive. But Americans don't like to wrestle with complex issues where every piece of a puzzle must be patiently found & fit. It is too hard to accept that our every move has an impact on the world. That every house was once home to someone else. In an effort to find the "quick fix", we have chosen DDT as one of our scapegoats. It will probably end this way because there is no reward for finding the truth. There is only reward in the discovery of new & better alternatives. And that's not a bad thing at all. It's just a shame that truth has to be lost on the way.
Our debate needn't end here. Perhaps someone else has more to offer on the subject. For the record, a pair of Peregrin Falcons is nesting on a building in downtown Bridgeport & another on the Aetna Insurance Bldg in Hartford.