HomeBrew on May 26 2009, 09:28 PM said:

Hi Homebrew, so do you mean that the UN Stockholm Convention on POPs (persistent organic pollutants) got it all wrong? And even if it were so, I think that this is way beyond the science (esp junkscience).
Would you eat DDT-tainted food and drink DDT-tainted water or spray it on your walls where you and your pregnant wife and a brood of little kids live knowing that there's the slimmest chance that it is detrimental to health? And for the other side of the coin, check this out...not heavy on the science for this primer tho (but they should have a lit base) but at least they've got a plan which can work if everyone is willing to do their part......

At least it's interesting how different studies can produce different results:

1. Junkscience:

"DDT was found to reduce tumors in animals."


"Rodent tests for a carcinogenic effect of DDT, DDE and TDE produced equivocal results despite extremely high doses (642 ppm of DDT, 3,295 ppm of TDE and 839 ppm of DDE)."


1b. Hazardous Substances Data Bank:

"Evaluation: There is inadequate evidence in humans for the carcinogenicity of DDT. There is sufficient evidence in experimental animals for the carcinogenicity of DDT. Overall evaluation: DDT is possibly carcinogenic to humans (2B).
**PEER REVIEWED**"

"CLASSIFICATION: B2; probable human carcinogen. BASIS FOR CLASSIFICATION: Observation of tumors (generally of the liver) in seven studies in various mouse strains and three studies in rats. DDT is structurally similar to other probable carcinogens, such as DDD and DDE. HUMAN CARCINOGENICITY DATA: Inadequate. ANIMAL CARCINOGENICITY DATA: Sufficient.
http://www.epa.gov/ngispgm3/iris on the Substance File List as of March 15, 2000>**PEER REVIEWED**"


2. Junkscience:

"Men who voluntarily ingested 35 mgs of DDT daily for nearly two years were carefully examined for years and "developed no adverse effects.""


2b. Hazardous Substances Data Bank:

"... SINGLE DOSE ... OF 10 MG/KG PRODUCES ILLNESS IN SOME BUT NOT ALL SUBJECTS EVEN THOUGH NO VOMITING OCCURS. ... CONVULSIONS HAVE OCCURRED ... WHEN DOSAGE LEVEL WAS 16 MG/KG OR GREATER ... LARGE DOSES LEAD TO PROMPT VOMITING, SO AMT ACTUALLY RETAINED CANNOT BE DETERMINED ACCURATELY. IN ACUTE POISONING SLIGHT DECR IN HEMOGLOBIN & MODERATE LEUKOCYTOSIS WITHOUT ANY CONSTANT DEVIATION IN DIFFERENTIAL WHITE COUNT HAVE BEEN OBSERVED IN VOLUNTEERS. THESE FINDINGS ARE CONSIDERED SECONDARY TO NEUROLOGICAL EFFECTS.
**PEER REVIEWED**"

"... STUDIES OF DDT IN VOLUNTEERS HAVE BEEN DESIGNED ... TO SEARCH FOR POSSIBLE EFFECTS OF DOSES CONSIDERED TO BE SAFE. IN 1ST OF THESE STUDIES, MEN WERE GIVEN 0, 3.5, & 35 MG/MAN/DAY. THESE ADMIN DOSAGES, PLUS DDT MEASURED IN MEN'S FOOD, RESULTED IN DOSAGE LEVELS OF 0.0021 TO 0.0034, 0.038 TO 0.063, & 0.36 TO 0.61 MG/KG/DAY, RESPECTIVELY, EXACT VALUE DEPENDING ON WT OF EACH INDIVIDUAL. SIX VOLUNTEERS RECEIVED HIGHEST DOSAGE OF TECHNICAL DDT FOR 12 MO, & 3 RECEIVED IT FOR 18 MO. A SMALLER NUMBER OF MEN INGESTED LOWER DOSAGE OF TECHNICAL DDT OR 1 OF DOSAGES OF p,p'-DDT FOR 12 TO 18 MO. NO VOLUNTEER COMPLAINED OF ANY SYMPTOM ... SAME RESULT WAS OBTAINED IN 2ND STUDY IN WHICH SAME DOSAGES WERE GIVEN FOR 21 MO & VOLUNTEERS WERE OBSERVED FOR MINIMUM OF 27 ADDNL MO.
**PEER REVIEWED**"
(here the websites agree, sorry for capitals, it was on this website)

Anyway I agree to casey's position, why should we exposure human beings to such a risk, if there are better and less hazardous measures, as mentioned above (removal or coverage of open water tanks, cisterns etc.; use of nets (LLIN = long lasting insecticidal nets without DDT but alternative insecticides); use of alternative insecticides such as carbamates, organophosphates, pyrethroides; drain swamps; teach the population; use of new drugs such as Artemisinin).
Of course it's more expensive, laborious, and time-consuming. One has to think and use strategies that fit to the conditions found in such places (sometimes even the use DDT in hot spots of Malaria infections may be useful). And not just go back to out-dated measures, with known and unknown long-term risks to human health and the environment, because it's easy and cheap.

casandra on May 26 2009, 11:58 PM said:

I voiced no opinion at all on either side of the DDT debate; I simply pointed out that the web page I had linked to cited scholarly works to back up most of their statements, and invited others here to draw their own conclusions.

I have no opinion on whether the UN Stockholm Convention on POPs got it right or wrong, because I haven't looked at the findings of this convention nor the studies on which they (presumably) based their conclusions.

Asking homebrew if he'd eat DDT, etc. is an emotional argument - silly and irrelevant to the question. As Paracelsus said - the poison is in the dose (and the route of administration). As with the use of any material, we need to consider the benefit vs. the risk.

My bias here is the Silent Spring was more fiction and unfounded conclusion than scientific work amd much of the work I've read that is technically sound works at a technical rather than practrical level.

From the other (benefit) side - consider the positoon of the Malaria Foundation International
http://www.malaria.org/index.php?option=co...7&Itemid=42

GeorgeWolff on May 27 2009, 05:46 PM said:

Of course it's a silly emotional argument....really George, you can give Simon Cowell a run for his Idol money....oopps, sorry, that's ad hominem but you're right, it's not a fair question for Homebrew. What I just wanted to illustrate (in my usual twisted way) was that it's very easy to criticise and say that it was a wrong UN decision and that DDT is still the most effective intervention so just give them the DDT..and then wonder if you'd still feel/decide the same way if you're the one who'd be exposed to this chemical and if indeed there are no better, workable alternatives. Why do you think Carson's book provoked such an public outcry and propelled the environmentalist movement? ' a hypothetical american town desolated and forever silenced by man's callous/even brutal treatment of nature', 'the obligation to endure gives us the right to know', 'beware or else nature will turn around and bite you in the bum' etc.

She was maligned for being a hysterical alarmist by the chemical industry and some key figures from the dept of agriculture. But do you really think that the persidential science advisory committee which in the end endorsed her scientific claims based their decision on wild speculations? You didn't have scientists in that group- just bureaucrats and policy makers who were not qualified to make any judgment...this is soo hard to believe...

Though I'm not a fan of emotional arguing, Carson's book aroused interest in the readers (laymen as it was written mostly for them) about a serious problem. Thinking and dealing with this topic started that continues until today. Mission accomplished.
An academic textbook would have been ignored by the public and now collect dust in the library.