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DDT or Malaria -- Which is Worse? 163

Posted by Cliff from the a-choice-between-two-evils dept.
Assassin bug wonders: "Although the topic of malaria has been discussed on Slashdot, DDT use has not. After having banned DDT (C14H9Cl5)" in 2004, Tanzania has reversed their ban on DDT use. What is the Slashdot community's opinion regarding the use of DDT for mosquito control versus genetically modified mosquitoes?"
"Key facts to consider:
  • Insects have developed resistance, for every tactic that has been used against them (including biological control, crop rotation, and various chemicals)
  • Although the direct effects of DDT on humans might be benign, the effects on wildlife and the environment are well documented
  • In some countries, such as India, popluations of DDT-resistant mosquitoes exist
  • The fitness (i.e., reproductive success in the wild) of mutant mosquitoes is not well understood."
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DDT or Malaria -- Which is Worse? More

DDT or Malaria -- Which is Worse?

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  • DDT (Score:3, Informative)

    by Erich ( 151 ) on Thursday May 11, 2006 @10:03PM (#15314591) Homepage Journal
    DDT use is allowed (even in the US, I think) for application around the home, ie. treating walls and such.

    The alleged environmental impact was when the use was ultra-widespread, like dusting crops.

    DDT is effective at fighting malaria in much of the world, applying just around the home, but chemical manufacturing companies largely stopped making it after it got a bad name from the environmental concerns.

    • Re:DDT (Score:5, Informative)

      by barawn ( 25691 ) on Friday May 12, 2006 @12:16AM (#15315224) Homepage
      but chemical manufacturing companies largely stopped making it after it got a bad name from the environmental concerns.

      You mean like after it decimated the ecosystem on Borneo, forcing 14,000 cats to be parachuted in to stop the population from dying of bubonic plague and typhus.

      Alleged? Alleged? C'mon. This is well documented. DDT doesn't kill humans, but it sure does screw with a lot of other animals. It can be used intelligently, but it can also be used stupidly, too.

      It's not even clear that when it's used intelligently that it's cost effective to do so. USAID doesn't believe that it is.

      • Link to Harvard about Borneo (Score:5, Informative)

        by BobPaul ( 710574 ) * on Friday May 12, 2006 @01:09AM (#15315452) Journal
        Found your comment interesting, so I googled it and found this very interesting. Thought others might find it a good summary.

        Click on the top link about borneo on this Harvard Page [harvard.edu]
        • Here [iucn.org] is another much much more detailed description (down in Malaria control), and here [harding.edu] is an eye-witness account from 1959 of the cat drop itself.

          Note that the author of the cat drop was a little too dismissive of the dangers of the rats (he seemed to be more concerned by the fact that they were nibbling people's toenails and eating transistor radios) but hey, he's a reporter. Can't blame him for that.

          Still, though, I really recommend the Charlotte Pomerantz book [amazon.com]. It's a well-written children's book which

      • Re:DDT (Score:3, Funny)

        by gstoddart ( 321705 )
        You mean like after it decimated the ecosystem on Borneo, forcing 14,000 cats to be parachuted in to stop the population from dying of bubonic plague and typhus.

        Not to derail your very good point, but ....

        Parachuting 14,000 cats? If anotehr poster hadn't already posted corroborating links I'd be disbelieving you right about now.

        Man. The sheer visual of 14,000 feline paratroopers just gives me the giggles.

      • Re:DDT (Score:4, Interesting)

        by Wavicle ( 181176 ) on Friday May 12, 2006 @03:35PM (#15320501)
        1) DDT did not decimate the ecosystem of Borneo
        2) There were no outbreaks of plague or typhus. Every instance you find of someone saying this is someone retelling a trumped up story they heard. The cats were dropped because there was FEAR an outbreak would occur. It didn't.
        3) The insect control measures in Borneo are today considered to have been a great success. The problem of malaria went away. Thousands of children lived who might otherwise have died, and as I mentioned, there was no outbreak of plague or typhus.
        4) Sorry, I just don't take USAID's position on DDT seriously. They have in the past shown themselves to be tools of of the anti-DDT environmental lobby.
        • DDT did not decimate the ecosystem of Borneo

          Okay, okay, decimate is too strong a word. But it did damage the rivers severely causing large fish die-offs, and when you kill off an entire species in the areas (cats), that's not exactly "no effect."

          There were no outbreaks of plague or typhus.

          Curiously enough, I didn't say there was. I said the cats were dropped to stop the population from dying. It worked.

          Every instance you find of someone saying this is someone retelling a trumped up story they heard. The cat

      • Re:DDT (Score:3, Funny)

        by 14CharUsername ( 972311 )
        Interestingly, seeing 14,000 cats parachuted in to Borneo can be caused by both DDT and LSD.

  • Rachael Carson = Bad Science (Score:4, Informative)

    by FooAtWFU ( 699187 ) on Thursday May 11, 2006 @10:03PM (#15314600) Homepage
    From Why we need DDT [spiked-online.com]:
    In fact, DeWitt's 1956 article in the Journal of Agriculture and Food Chemistry came to a very different conclusion. DeWitt reported no significant difference in egg hatching between birds fed DDT and birds not fed DDT. Carson also omitted to mention DeWitt's report that DDT-fed pheasants hatched about 50 percent more eggs than 'control' pheasants. As to DDT causing cancer in humans, study after study reports no association between DDT exposure and cancer rates.

    Dr Joel Bitman and his associates at the US Department of Agriculture published an article in Nature in 1969, which found that Japanese quail fed DDT produced eggs with thinner shells and lower calcium content. Further examination of Dr Bitman's study revealed that the quails under experiment had been fed a diet with a calcium content of only 0.56 percent, whereas a normal quail diet consists of 2.7 percent calcium. Calcium deficiency is known to cause thin eggshells. After much criticism, Bitman repeated the test, this time with sufficient calcium levels, and the birds produced eggs without thinned shells.

    Following years of feeding experiments, scientists at the Department of Poultry Science at Cornell University 'found no tremors, no mortality, no thinning of eggshells and no interference with reproduction caused by levels of DDT which were as high as those reported to be present in most of the wild birds where "catastrophic" decreases in shell quality and reproduction have been claimed' (2).

    • Re:Rachael Carson = Knew what she was talking bout (Score:4, Interesting)

      by AlexanderDitto ( 972695 ) on Thursday May 11, 2006 @10:28PM (#15314719)
      "It is more sensible in some cases to take a small amount of damage in preference to having none for a time but paying for it in the long run by losing the very means of fighting [is the advice given in Holland by Dr Briejer in his capacity as director of the Plant Protection Service]. Practical advice should be "Spray as little as you possibly can" rather than "Spray to the limit of your capacity.""

      -Rachel Carson, Silent Spring

      Note the last sentence. It seems she KNEW that in some cases, not using DDT would amount in a LARGE amount of damage, and in these cases, using DDT would be unavoidable. Spray as little as you possible can seems to be common sense, but may not be to the uneducated.

      It IS known that DDT builds up in the tissues of organisms high up in food chains. Perhaps studies don't indicate that DDT directly causes any sort of harm, but I don't think having an organochlorine in ANY fleshy parts is a good thing.
      • You don't address the Scientific question. This is the first thing I've heard contrary to the "fact" that DDT causes thin shells. If yours is the best defense to this accusation then it must be true.

        Or do you just mean to say that faking Scientific results is okay as long as your heart is in the right place?

        -Peter
        • Read: http://www.reason.com/rb/rb010704.shtml [reason.com] for a simplified history on the subject.

          This is the first thing I've heard contrary to the "fact" that DDT causes thin shells.

          It's not a question of ALL birds it about a small number of sensitive species.

          "Anderson notes that DDT and DDE levels in nature have been falling for decades. Populations of bald eagles, peregrine falcons, ospreys, and brown pelicans have all bounced back. In 1969, researchers reported finding total DDT accumulations ranging fro
        • "Or do you just mean to say that faking Scientific results is okay as long as your heart is in the right place?"

          Google on "bone marrow transplant breast cancer faked study"

          Yes, it's perfectly acceptable until you get caught.

    • Spiked-online = dodgy quote?!? (Score:4, Insightful)

      by wall0159 ( 881759 ) on Thursday May 11, 2006 @11:21PM (#15314965)
      Your quote says this:

      "DeWitt reported no significant difference in egg hatching between birds fed DDT and birds not fed DDT"

      and then, one sentance later, this:

      "DeWitt's report that DDT-fed pheasants hatched about 50 percent more eggs than 'control' pheasants."

      Now, I don't know who DeWitt is, and I don't claim to be knowledgable about DDT, but these sound like contradictory statements to me!

      Maybe spiked-online and/or DeWitt have a vested interest in DDT...
      • "DeWitt reported no significant difference in egg hatching between birds fed DDT and birds not fed DDT"

        This seems to me to be a very poor way to study to enviornmental toxicological effects of DDT, if it is at all what it sounds like. For one thing, DDT does break down in the environment to a number of different but closely related compounds. Furthermore, just because you ingest something doesn't mean it is absorbed in a biologically active form.
    • And I suppose that the cats parachuted [harvard.edu] into Borneo to stop a plague epidemic after DDT destroyed the local cat population were 'bad science' too?

      Look, DDT has uses. It can be useful under proper control. But we don't exactly have a good track record of handling these things. And DDT does destroy ecosystems. It has. That's fact. That's not bad science. It happened.

      It's healthy to be skeptical of its use. History is littered with examples where we just tried to mildly affect an ecosystem and ended up demolish
      • What does it have to do with whether or not DDT causes eggshell thinning?

        • It doesn't.

          It has to do with whether or not DDT causes environmental damage, and whether or not DDT should be used to fight malaria. Which is, y'know, the topic being discussed.

          Just because some of the main reasons to ban DDT were bogus doesn't mean that it's as safe as hand soap.

  • Riiiiibit (Score:3, Funny)

    by Anonymous Coward on Thursday May 11, 2006 @10:07PM (#15314614)
    The answer is frogs. Big freaking frogs. With lasers on their heads!
  • In areas where the human population is taking a beating because of the pests, use the best method we have available to kill them. Right now these particular pests seem most susceptible to DDT. So use it in those selected areas. The mosquitoes targeted will most likely develop resistance to it but in the meanwhile it will give us some time. As in the warfare against bacteria, our antibiotics are constantly being defeated as we are forced to develop newer methods. But to give up a currently viable altern

    • Re:DDT Use (Score:5, Informative)

      by Detritus ( 11846 ) on Thursday May 11, 2006 @10:34PM (#15314749) Homepage
      The problem with pesticides and antibiotics is that they are often abused and misapplied through ignorance, stupidity and greed. Read how [telegraph.co.uk] China may have fscked the entire world by using a human antiviral drug in an effort to protect the Chinese poultry industry from bird flu.
      • Thank you for that link, I bookmarked it. The last time I related that story, someone responded saying that the Chinese government would never do something like that, and I didn't have a link handy.

      • Re:DDT Use (Score:3, Interesting)

        by Hoplite3 ( 671379 )
        I still think that the best source of stories on the overuse of erratication programs is Laurie Garett's The Coming Plague. She discusses how the Small Pox eradication (one of the most successful) weaponized small pox, how cleaning with bleach has bread super-bacteria in some hospitals that can be cultured on undiluted Clorox.

        Her point (about antibiotics and mosquito control) was that we should try to domesticate of microbal advisaries. If you can produce a strain of a disease that has a short, mild infec

        • Re:DDT Use (Score:3, Informative)

          by will_die ( 586523 )
          how cleaning with bleach has bread super-bacteria in some hospitals that can be cultured on undiluted Clorox
          You are a little off here.
          The problem is that the use of non-bleach clearers are creating bacteria that are resistant to anything but bleach based cleaners.
          Bleach is the best thing around to kill bacteria the way it works is to disolve the skin wall, no way to build up a resistance to that.
    • The problem isn't mosquitos, but the malaria they carry. Furthermore, the Slasdot title is confused, the choice isn't between DDT and Malaria, but DDT and mosquitos that are no longer malaria carriers and therefore cannot transmit it to humans.
    • Has there been successful testing of releasing sterilized male mosquitoes to control their population? I know there were studies proposed, but I don't know if widespread testing was done.
    • In areas where the human population is taking a beating because of the pests, use the best method we have available to kill them.

      It is neither appropriate nor desirable to use extermination in lieu of proper quarantine procedures, when treating infectious diseases. In fact, the point of treating these diseases is to prevent death.

  • It's true (Score:4, Insightful)

    by Henry V .009 ( 518000 ) on Thursday May 11, 2006 @10:16PM (#15314662) Journal
    The DDT necessary to save thousands of lives in the world's malarial hellholes is miniscule compared to that required for the crops of even a medium farm.

    And DDT-hate on the part of international aid organizations (international aid is the entire health budget for some impoverished African countries) has led to countries refraining from using DDT.

    Not using DDT kills poor Africans.

    DDT is the cheapest, most effective way of protecting against the world's deadliest disease. Anti-malarial netting is somewhat effective, but simply does not compare to DDT.

    • Re:It's true (Score:3, Insightful)

      by AlexanderDitto ( 972695 )
      Alright, so say they DO start using DDT in a more widespread fashion to kill off these mosquitos. Ignoring the possible environmental aspects (which, from what I'm now reading, are iffy in themselves), when does it stop? When will Africa be safe from these mosquitos, allowing them to stop using the DDT?

      The answer is never. Unless ALL malaria is wiped out in ALL organisms around the world, DDT will have to be continously used FOREVER to prevent malaria from breaking out.

      This will eventually stop working. Som
      • a possible (or even certain) problem in the future is better thqan that same problem now. by the time DDT loses effectiveness we might have better treatment for malaria or better cheap insecticides.

        obviously the risk to the environment is a factor but i'm not willing to tell people they have to get sick and die because we don't want the jungle they live in/near contaminated with insecticides.

        it should be their choice.

        • Re:It's true (Score:2, Insightful)

          by AlexanderDitto ( 972695 )
          You're giving the choice to people who may not exactly have the best idea of the worldwide scope of their actions. That's the problem with most people and the environment. Somebody throws an SEP field around it or figures that the one teensey thing they do in their backyard won't affect the whole big wide world, and then you've got a quarter billion people dumping lead paint down their storm drains. "We'll deal with it in the future," they say.

          by the time DDT loses effectiveness we might have better treatme
        • a possible (or even certain) problem in the future is better thqan that same problem now. by the time DDT loses effectiveness we might have better treatment for malaria or better cheap insecticides.

          That takes research that isn't being done and especially money that isn't being spent. I heard a program on Science Friday that said that many strains of malaria are almost totally resistant against current drugs, in part because they are being misused. I think the comment was that there were many more drugs be
        • You're missing the point somewhat though.

          We have a better cure for malaria. It's a combination of education, and pennicillin. The trouble is, it's not a simple fix. It requires a generation to transition to that solution, because people won't be educated enough to use antibiotics in a way that isn't harmful quickly enough. DDT use should be combined with economic progress and education.

          In simpler terms, wealth cures malaria, and malaria prevents wealth. DDT breaks the chicken and egg cycle.
      • Mosquitos that are resistant to malaria, meaning that they are no longer carriers of malaria and can no longer spread it to humans, but the Slashdot article was very muddy on that!

  • offtopic, but hey: (Score:2, Interesting)

    by jannesha ( 441851 )
    The insects were heard to complain
    That man had poisoned their rain
    The cause of their sorrow
    Was para-dichloro-
    diphenyl-trichloroethane
    ...ahh, takes me back to third-year organic chem...
    • I always preferred The Day They Parachuted Cats on Borneo [amazon.com], by Charlotte Pomerantz. It's unfortunately out of print now, though I still have a copy.

      It's an entire story of the Borneo DDT disaster, told in rhyme. To quote:

      "When they sprayed my hut with insecticide,
      My rat catching cat soon sickened and died.
      When the rats crawled in, I was filled with fear:
      The plague can kill more than malaria here.
      When my roof beams caved in, I moved next door.
      Until their roof beams collapsed to the floor.

      But please, do not th

      • wholesale area spraying of DDT is inappropriate, but the Africans, IIRC, use it as a household spray so that there isn't the same kind of accumulation of the stuff in the food chain.
        • Right. Unfortunately, the main benefit of DDT was that it was effective on a large scale, and so it could be used for mass spraying to essentially eradicate the mosquito population. On a smaller scale, it's not exactly cost-effective.

          See this [nih.gov] paper on a cost comparison between DDT and insecticide-treated nets.
  • ...or give me Death. No, really.

  • I choose life! And as a bonus, there's genetic improvement! Now when will I be able to improve my own genes?

  • Wait... (Score:3, Funny)

    by fak3r ( 917687 ) on Thursday May 11, 2006 @10:43PM (#15314797) Homepage
    Where's the Cowboy Neil option?

  • Interview? (Score:1, Funny)

    by Anonymous Coward
    Has Jake The Snake been inteviewed yet for this article?

  • 100 things you should know about DDT (Score:4, Informative)

    by bill_mcgonigle ( 4333 ) * on Thursday May 11, 2006 @10:53PM (#15314845) Homepage Journal
    Here's an interesting DDT FAQ entitled 100 things you should know about DDT [junkscience.com].

    • This site opposes the consensus backed up by evedence that the global mean tempature has been rising due to CO2 concentration rising. I would say that puts their reliability in the toliet. I personaly like to decide things based on facts, but you might not.
  • DDT is better! You can't use Malaria for a shell AFAIK.

    [Not an original PDP-10 hacker, just a poseur.]
  • No discussion of DDT would be complete without a link to Tim Lambert's DDT page [scienceblogs.com].

    Dr. Lambert has made a hobby of following DDT opponents' crazy theories, as well as the anti-global-warming crowd, and the Big Money that makes both possible. For a compact overview of DDT falsehoods, check out DDT ban myth bingo [timlambert.org].

  • When my mom was a kid, she and her friends used to play in the clouds of DDT spray from DDT trucks. It didn't seem to have much of an impact on her, which amazes me since it can't possibly be good to breath it in right??? Though it might explain quite a bit about me....
    • So did I, and I sprayed the hell out of the Chicken coops with it as a kid. Trus me , litterally FOGGING the coops, I can PROMISE there was no adverse effect to egg production or mortality of the brood,

      I always as a kid (ddt was banned many years before we stopped using it) I often thoug "Was it the DDT killing off the insects that the smaller birs ate, that the larger birds ate them that caused the decline ?"
      Then around the early to mid 1980's I started seeing birds I had never seen, and hawks in quantit

  • either/or? (Score:4, Insightful)

    by mshurpik ( 198339 ) on Friday May 12, 2006 @12:03AM (#15315169)
    > DDT or Malaria -- Which is Worse?

    I don't think it's a 1:1 comparison. Killing mosquitoes is analagous to killing terrorists...you don't stop them from breeding. A proper mosquito-control regimen involves maintaining healthy (warm summer) climate so dragonflies are healthy and eat the mosquito larvae the moment they pop out of the pond.

    You should see a pond with dragonflies hovering...it looks like the Congratulations screen from a videogame. Each dragonfly takes a 10' radius, so a group of them has the whole pond on lockdown.

  • There were no scientific studies done, DDT wasn't banned on science at all. For a site that claims to be about technology, the people here at slashdot tend to subscribe to a LOT of JUNK SCIENCE.
  • Oh wait, no it's not. Malaria, obviously.
  • This was up in our school's biology lab. I have no idea who the original author is:

    A mosquito was heard to complain,
    A chemist had poisioned his brain,
    The cause of his sorrow
    Was 4-4-dichloro
    Diphenoltrichloroethane

  • False Dichotomy (Score:3, Interesting)

    by Dr. GeneMachine ( 720233 ) on Friday May 12, 2006 @04:02AM (#15315946)
    It is not like DDT is the only available pesticide - perhaps we chose on that doesn't tend to accumulate in the food chain this time? An interesting approach would be the use of Bacillus thuringiensis var. israelensis, a bacterium that is highly toxic for mosquito larvae. It is harmless to basically everything else, except for some kinds of insects, and has been used succesfully against other insect infestations. It can be aerosolized and sprayed just like a chemical pesticide.

    Then there is Methoprene - a compound that is similar to an insect growth hormone. It targets specifically insect larvae and prevents them from reaching their next stage of development. Again, it can be used like any conventional insecticide, does not accumulate and is easily biodegradable and non-toxic to anything but insects. Has been successful in trials against mosquitoes as well.

    So, why DDT?

    • Because you can spray it in your house without getting sick.

      We aren't talking about using DDT as a wholesale agent-orange-nuke-the-forest type thing. Africans use it in their houses to kill mosquitos because it is much safer than other residential pesticides.

      Except, of course, the UN pressures them not to do it on the off chance that bald eagles might visit those houses on their way to their nests in colorado.
    • Methoprene (commerical name: Altosid) and BTI and B. sphaericus are all very effective larvicides. The problem is you can't solve the Malaria problem with them, because you can't find all the habitat, and if you could you couldn't get to it fast enough, and if you could get to it fast enough you couldn't afford to treat all of it with these materials.

      Example: some mosquitoes breed in containers. Their reproductive strategy is to lay their eggs some place where they will be wetted after a rain, thus ensurin

  • Malaria vs ddt (Score:2, Insightful)

    by linuxgnuru ( 113765 )
    Where considering I am currently living in Tanzania helping installing Linux servers for rural ISPs, after only 3 months I have seen 14 people die from Malaria. For these people, they live day to day and do not think of the future. So for them, using DDT as a right now treatment vs possible cancer many years from now, there is no debate.
  • Widespread use of DDT for crop-spraying has lead to DDT-resistant mosquitos in many parts of the world. Despite this, and despite some other adverse effects, DDT is not banned. DDT is recommended by the WHO for residual indoor spraying as part of an anti-malaria campaign. Governments and NGOs fund residual indoor DDT spraying programs in many countries. However, for saving lives, DDT is far less effective than treated bed-nets, and each is less effective than an integrated anti-malaria campaign.

    For rea

    • Why so much DDT love here? The parent has a link to good info:
          - DDT does kill mosquitos, and is being used appropriately already.
          - Doing more DDT spraying is not the best way to crontrol malaria
          - Yes, the hazards to the environment are real

  • old news (Score:3, Informative)

    by argStyopa ( 232550 ) on Friday May 12, 2006 @06:51AM (#15316267) Journal
    The "DDT is dangerous" has been conclusively and comprehensively DEBUNKED years and years ago. There is NO reason this crap needs to continue, except for the psychological agenda of the enviro-facist movement.

    http://www.junkscience.com/ddtfaq.htm [junkscience.com]

    Basically, 'Silent Spring' was based on test data that was wrong.
    The birds whose eggs were shattering, had been raised on a diet containing less than 20% of the calcium they usually got. Duh. Low calcium = weak eggshells.
    When the experiment was repeated with a proper diet, there was NO such finding, even in birds HEAVILY fed DDT.
    Even the original authors of the experiment had, by 1971, turned their investigations more to PCBs, and discounted DDT as an issue with bird populations.

    An administrative Judge ruled even at the time that DDT wasn't dangerous.
    Nevertheless, the administrator of the then-new EPA ruled it would be universally banned...and then promptly went to work for the exact same anti-DDT enironmental lobbying group, after he left he EPA.

    But I find that DNR staff, ecological speakers visiting schools, reporters, etc all have cheerfully and unquestioningly swallowed the Kool Aide on this because of its SEMINAL impact and justification of the environmental movement. To be fair, when confronted constructively about it, are rather shocked but eventually persuaded that there MIGHT be some doubt...which is a lot when you're attacking such a sacred cow. However, I have yet to see anyone subsequently change their presentation, curricula, or (effectively) beliefs.

    Question that DDT might not be dangerous? That might make people wonder about the validity of the whole "movement", if they could be shown to be such easily-gulled rubes.

    Heck, it might even make you think global warming is BS...but no, that MUST be true, right? Scientists say it is.

    • But I find that DNR staff, ecological speakers visiting schools, reporters, etc all have cheerfully and unquestioningly swallowed the Kool Aide on this because of its SEMINAL impact and justification of the environmental movement. To be fair, when confronted constructively about it, are rather shocked but eventually persuaded that there MIGHT be some doubt...which is a lot when you're attacking such a sacred cow. However, I have yet to see anyone subsequently change their presentation, curricula, or (effect

  • SKEETERS! (Score:2, Funny)

    by lpcustom ( 579886 )
    When huntin Skeeters use a Skeeter Trap [mosquitocontroltrap.com]!

  • DDT or Malaria? (Score:5, Informative)

    by hey! ( 33014 ) on Friday May 12, 2006 @08:48AM (#15316607) Homepage Journal
    This is known in reasoning circles as a "false dilemma".

    DDT is very cheap and effective in the spot you're applying it to. And therein lies the problem: it's almost too good. The step from using it where it is effective and safe to using where it has unwanted side effects has historically proven to be very short.

    Lacking DDT, the industry has had to develop alternative approaches, such as IPM, which are more information and biology centric, and new materials which are more narrowly targetted and which break down in the environment in a more benign way. This requires more up front effort and investment, but in the end is probably more effective.

    Consider one common traditional use of DDT: Fogging to kill adult mosquito populations. The mosquito has to encounter the DDT on the wing or land in a place where there was residual toxic effect. Since the mosquito could be literally anywhere, this means you must saturate an entire area surrounding human habitations by fogging it. In the old days, you waited for a nuisance problem or a disease outbreak, and then fogged everything you could reach and hoped you were in time to stop human transmission. I've talked to public health researchers who believe that most such efforts tend to be undertaken after the actual problem has past. Or if you were proctive, you might try to treat preventatively, killing not only mosquitoes (you never get them all), but beneficial insects as well.

    Today, if you can manage it, you find the aquatic habitat in which mosquito larvae hatch and develop, and if you can't drain it (e.g. artificial containers like abandoned machinery), you treat it with a narrowly targeted larvicidal material. BTI and Baccillus sphaericus for example, are endotoxic crystals that only act in aquatic larvae with high pH guts -- midges and mosquitoes mainly. If the mosquitoes have pupated, you treat with a material which forms a film on the water, blocking their breathing tubes; in the old days we used diesel oil, now we have specially formulated oils and even alcohols that form monomolecular films.

    However, this involves knowing where the habitat is, which is information-centric problem. You need trained inspectors in the field who know what to look for and what to use. Even fogging operations are much more sophisticated; you don't just spray and pray. You have a trapping program to monitor adult populations so you don't end up fogging the wrong places. The technology involved for trapping is mostly rudimentary , but you need trained users who can sort and identify mosquitoes by species. Not all mosquitoes bite people or carry disease after all. Furthermore you'd be surprised how many untrained people mistake other insects such as crane flies for mosquitoes.

    But it remains thrue, for the developed world Information + Biological Knowledge + Specific action pesticides = Control with fewer side effects.

    With respect to human and animal health, there is little threat to human health from direct exposure to DDT in the concenrations that are effective. The established problem with DDT is bioaccumulation: the concentrations of DDT and chemical products of DDT break down are amplified as they go up the food chain. In certain key applications, such as house interior treatments, this is not a concern however, so it should be possible to use DDT this way.

    In places like Africa, DDT used in domestic treatments would be a tremendous boon. The forms of Malaria that infect humans, unlike many other mosquito borne diseases such as the various encephalitis agents, don't have a natural animal reservoir. It spreads from person to person. Personally, I can imagine Malaria being eradicated, like smallpox, and domestic DDT treatments could play a part in this, if its use could be monitored and controlled.

    I've been involved with equipping teams to go to Africa for malaria surveillance and for house treatments. One of the problems you face is that in many poor areas, theft is rife. I've had guys tell me they have

    • Mostly correct, except you forgot to mention that DDT is actually in use in malaria prevention right now [globalpolicy.org] in 22 countries. Most of these countries are in Africa, but I'd appreciate it if you'd attempt to distinguish between individual countries and the second largest continent on the planet, since malaria is simply not a big problem in large areas of Africa such as Algeria (11th largest country by area in the world). And to the Steve Milloy fans, fears of creating DDT resistant strains of mosquitos are not

      • distinguish between individual countries and the second largest continent on the planet,

        Well, I can only speak of only a handful of countries in Africa in any case, mostly through people I know who are working in vector borne disease control. My expertise is more with viral stuff in temperate regions.
  • Is this like the vi or emacs question?
  • Male "occupational" exposure to DDT causes birth defects in their children.

    [ehponline.org] http://www.ehponline.org/docs/2004/6759/abstract.h tml [ehponline.org]

    http://www.birthdefects.org/archives/News_aug01.ht m [birthdefects.org]
  • All these people who think that Googling for facts makes them experts are fools. If you think you're getting *any* useful or intelligent, verifiable answers out of any of these people (including me) then you deserve what you get when you listen to them.

    The same goddamn thing happens every time someone pulls out an Ask Slashdot where medical advice or scientific debate is requested. For eye treatments, for pesticide discussions, for disease treatments, this site is so full of armchair wannabe scientists whos
  • DDT or Malaria -- Which is Worse?... after reading your biased 'facts to consider' list, I think you meant to say: "DDT or Malaria -- DDT is worse."

    If you are going to approach this article as a discussion piece and offer 2 sides, why give a list of facts which bluntly push the reader in a certain direction? Why not add in some Malaria stats like how it causes about 350-500 million infections with humans and approximately 1.3 - 3 million deaths annually. (these numbers might not be accurate, I pulled the
  • DDT is effective, and harmless. There is NO credible scientific evidence that it has ANY effect on humans, OR wildlife. It was banned because of fake research by environmentalists that scared the public, not because anybody had proven anything. A scared public can be pretty persuasive.

    So, which is worse, a safe and harmless chemical, or millions of people dying of Malaria? Gee, let me think.

    The banning of DDT in areas that need it for disease control is almost criminal, and the banning of it in North Americ
  • Or in Europe, we would still be spraying DDT all over the place. How did we get rid of malaria in the U.S. (and settle Florida)? If your kid was dying of malaria, you wouldn't think twice about a few soft eggshells.

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