Saturday, February 15, 2014

DDT and The Magic Study Machine!

By Rich Kozlovich
In December 2011 I wrote an article that was entitled, DDT - Lets Have Another 10,000 Studies!, saying;
“There have been thousands of studies regarding the effects of DDT on the environment, people and wildlife, and most of them were junk science….. conclusions in search of data. A number of years ago…..Dr. Rutledge Taylor...produced a film documentary about DDT called 3 Billion and Counting. …..At one point he had received almost 100 studies from one of the anti-DDT groups that claimed all sorts of things. He sent them to me and asked me to look them over…..
As I went through the first ten, very carefully outlining and taking notes on what was clearly wrong with those studies, I found out that they were filled with claptrap; speculation, weasel words, logical fallacies and weak associations. I went through the next ten just as carefully, without taking notes this time, and found the exact same pattern in all of them. I skipped to every fifth study only to find the same pattern over and over again. In short, these studies were nothing more than “academic welfare”!
You know what welfare is; pay without work; work being the operative word for producing something of value. And in these cases the ‘academic welfare’ produced preconceived conclusions. Conclusions in search of data! And everyone one of these studies was produced after DDT was banned! Why?”
Well, there is one thing we know for sure. Anti-DDT ‘studies’ will generate grant money, and the holy grail of science is grant money, and that’s what makes them ‘magic’. They’re magic because anti-DDT studies produce gold out of nothing. This kind of reminds me of that old Grimm brother’s fairy tale about Rumpelstiltskin and spinning straw into gold, and spinning is the operative word, because they're still desperately attempting to prove the ban really has some scientific basis instead of the political decision it really was.
One of of my readers sent me a link to this study, entitled, Elevated Serum Pesticide Levels and Risk forAlzheimer Disease, which claimed there ‘may’ be a link between Alzheimer’s and DDT, or in this case DDE the metabolite, or breakdown product, of DDT, finally concluding;
“Elevated serum DDE levels are associated with an increased risk for AD and carriers of an APOE4 ε4 allele may be more susceptible to the effects of DDE. Both DDT and DDE increase amyloid precursor protein levels, providing mechanistic plausibility for the association of DDE exposure with AD. Identifying people who have elevated levels of DDE and carry an APOE ε4 allele may lead to early identification of some cases of AD.”
The L.A. Times quotes and states;
"Over 80% of us have measurable levels of DDE in our blood, that is a reality," Richardson told The Times. "We get it from legacy contamination or food that comes from countries using DDT.  None of the people in the study had DDE levels that were way beyond what is found in the general population. "The levels we observed were not outside what you find in the top 5% of people in the United States," he said.
He added that some of the participants who had high DDE levels did not have Alzheimer's. "We need to do a lot more work to understand this association," he said."It may not be as simple as different levels of exposure.
With all those caveats, why was this study even published?
Let me tell you about weasel words and phrases, which has now been updated. When you start to look at these “studies” touted by the activists you find that there is one common thread. They are full of weasel words and phrases. This gives them a great deal of wiggle room because they never come out and definitively state that things are factual, they’re always ‘maybes’, and always scary ‘maybes’. Did it ever occur to anyone that this is nothing more than unfounded printed accusations, or even professional guess work? When this stuff makes it into print the media consistently fails to give the impression this may not be viewed as real science from the rest of the scientific community.
The American Council on Science and Health published an article on January 28, 2014 dealing with this entitled, “New study tries to link Alzheimer’s disease and DDT; media thinks it succeeded”.
“A small biomonitoring study of Alzheimer’s disease (AD) patients’ exposure to DDT, as compared to those of non-AD patients, came up with some statistically significant associations of otherwise no clinical significance. But that didn’t stop the news media from blaring the findings hither and yon, without giving a moment’s thought to the underlying mechanisms or significance. As usual.”
The article goes on to say;
“among 86 AD and 79 control patients [Editor's note; way to small a number to mean anything]. These levels were measured in serum. [DDT] is persistent (meaning it does not break down rapidly in the environment), as is DDE. But the levels measured in the study subjects were in the nanogram per milligram of cholesterol range: where a nanogram is one-millionth of a milligram! Simply put, the levels of DDE were somewhat akin to a drop of water in an olympic-sized swimming pool or less.
The problem with so many of these studies is in how they’re conducted, and what the media fails to tell everyone, and probably doesn’t understand anyway. The article went on to say;
The results, such as they are, indicated that the measured levels of DDE were 3.8 fold higher in the AD patients than the controls. Does this mean that the DDT/DDE caused AD in those higher-exposed? Not at all. In fact, the 2 study groups were assembled in 2 different locations, and each group’s numbers failed to show any effect. The authors took care of that inconvenient problem by pooling both groups, and voila! the statistics came back to them as they hoped.
But while that teeny-tiny amount may make this whole endeavor ridiculous, even more so is this simple fact: while the amount of DDT/DDE in the environment has clearly declined since it was banned and its manufacture nearly disappeared forty-plus years ago, the incidence of AD has climbed, indeed accelerated over that same period. That’s tough to explain using the “DDT linked to Alzheimer’s” scare story. Isn’t it?  Also, can you postulate the likely biological hypothesis for how these chemicals infiltrate one’s brain and interfere with memory on a progressive basis? No? Neither can I.
The author of the study is quoted as saying;
“That is exactly why this study was done: to try to discover some–any– remediable factor to try to prevent AD. Otherwise, we just feel helpless and at the mercy of fate.
ACSH’s Dr. Gil Ross notes;           
“ that’s a poor excuse for twisting yourself into a pretzel to come up with some bizarre linkage such as this study. And then there’s this insinuation that all pesticides are alike, which is utter nonsense.”
Of course groundwork must be laid for future grant chasing. “We have submitted grants to follow this up in much larger groups of people,” ….“That is the most important step — to replicate this and to have it in a much larger sample.” And so it goes, "The Magic Study Machine" is kept humming - filling the world with hype that is promoted by scientifically illiterate journalists.
But this is just the latest study generated by the Magic Study Machine over DDT. In January 2012 it was declared that DDT was now “linked” [another weasel word] to Vitamin D deficiency. Why didn’t the problem appear 40 years ago? And its really hard to believe whatever is left of DDT could have this kind of impact on anyone.
Then there was the December 2011 claim that DDT causes lung problems in babies?
Again, as Steve Milloy notes;
“DDT hasn’t been used in developing countries for decades. Now it causes lung infections? Here’s the study.The statistical associations are weak and insignificant, the data self-reported and a credible biological explanation for how DDE could possibly cause respiratory tract infections is non-existent —and, of course, respiratory tract infections in infants are so common thath it is absurd to even attempt to attribute them to trace levels of a ubiquitous metabolite of a long-banned insecticide. “
Then there was the May 2011 claim that, DDT causes diabetes, breast cancer and infant deaths.  Steve Milloy states;
I traced the diabetes claim to a study published in the July 2009 Environmental Health Perspectives. Aside from the usual fatal flaws of weak association epidemiology, this study’s assertion that DDT metabolite DDE was associated with incident diabetes is laughable since the average body mass index (BMI) of the study subjects was 33.2 — e.g., meaning that the average study subject was likely to be obese (check out this chart to see what height/weight combos make for a BMI of 33+). Moreover, no significant associations were reported for study subjects with a BMI less than 29. I don’t know whether obesity leads to diabetes or diabetes leads to obesity, but there’s no evidence that DDT is involved.   As to the breast cancer risk claim, I last addressed this issue in an October 11, 2007 column, responding to an October 2007 Environmental Health Perspectives study.
What about infant deaths?
“The National Institute of Environmental Health Sciences study referred to by the New York Times doesn’t even try to associate DDT with nonmalarial infant death. It instead only estimates nonmalarial deaths that may be associated with DDT spraying, the alleged “association” being based on three studies“suggesting” that DDT exposure may increase pre-term delivery and small-for-gestational-age births, and shorten the duration of lactation. “
Here’s Steve’s quick take on those three studies:
§ Association between maternal serum concentration of the DDT metabolite DDE and preterm and small-for-gestational-age babies at birth is an effort to retrospectively blame DDT for premies and underweight births 35 years after the births. But this can’t be credibly done with biased data and weak/inconsistent statistical associations.
§ DDE and Shortened Duration of Lactation in a Northern Mexican Town reports statistically insignificant results.
§ Polychlorinated Biphenyls (PCBs) and Dichlorodiphenyl Dichloroethene (DDE) in Human Milk: Effects on Growth, Morbidity,and Duration of Lactation confounding risk factors were not considered in a multivariate regression model (i.e., all at the same time), so its hard to blame DDT on even a statistical basis.
“So contrary to the New York Times‘ assertion, there is no credible evidence that DDT has anything to do with diabetes, heart disease or infant deaths. Moreover, given that one million children under the age of five die every year from malaria, even if DDT did increase the risk of diabetes, breast cancer and infant death, those risks would be better than the alternative. While the Times misinforms millions are dying needlessly.”
One thing will become clear for those of you who really want to understand what’s going on with these studies. So often these “Magic Studies” are conclusions in search of data.  They involve data dredging for associations and associations are not proof of causation, and invariably they are incapable of demonstrating the biological mechanism that supposedly make these things happen.
As for the Alzheimer study;  you have to wonder if it ever occurred to these people the reason this problem is becoming so pronounced is because more people are living longer and the real cause is “multiple birthday syndrome”? Did it ever occur to these ‘scientists’ that these people might not have been able to experience “multiple birthday syndrome” without the advent of DDT?
For those of you who could care less about the facts you can take solace in one reader’s caustic remark; “That settles it…DDT is now on double-secret probation!”  And the Magic Study Machine will soon crank out another crank study proving that DDT does ________, (just fill in the blank).  Who knows, you may be able to get a grant to study “something”, or even 'anything' , just so long as 'something' or 'anything' is caused by DDT.

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