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DDT in Africa

  1. Jan 7, 2006 #1

    Mk

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    Everytime I hear about it I get mad. What the hell's going on here? Countries (most notably the United States), provide tons of foreign aid in many forms, yet they do not send in any DDT. Thousands of people in Africa die everyday, and we send them mosquito nets. DDT would take care of that pretty well wouldn't it?

    There's gotta be a good reason. It seems like more and more scientists are getting together and telling people about it.
     
  2. jcsd
  3. Jan 7, 2006 #2
    The U.S. doesn't send DDT to Africa because they banned it
     
  4. Jan 7, 2006 #3
    I remember watching a documentary about this a few weeks ago on ABC. A small dose of DDT can prevent the diseases carried by mosquitos. The United States banned it because it caused some environmental problems. The U.S is not going to pay for something they won't use themselves.
     
  5. Jan 7, 2006 #4

    Hurkyl

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    And, for example: http://news.bbc.co.uk/1/hi/world/africa/1677073.stm

    Perhaps surprisingly then, DDT is not used in Mozambique and the authorities say they do not want to use it.


    I found this excerpt from a 1977 TIME:

    Resistant mosquitoes are defying DDT and infecting millions"We are in a strategic withdrawal. The days of euphoria are over." With those words, a World Health Organization official last week gloomily characterized the current state of man's long battle against an ancient scourge: malaria.


    More recently, if we can believe Wikipedia:

    In the period from 1934-1955 there were 1.5 million cases of malaria in Sri Lanka resulting in 80,000 deaths. After an extensive anti-mosquito program with DDT there were only 17 cases reported in 1963 and the program was halted. Malaria later rebounded to 600,000 cases in 1968 and the first quarter of 1969. Some proponents of DDT consider this an example of environmentalism trumping public well-being even though the use of DDT was ended more due to the lack of continuing need than due to environmental concerns. Spraying with DDT was resumed but many of the local mosquitoes had acquired resistance to DDT in the interim, presumably because of the continued use of DDT for crop protection, and so it was not nearly as effective as it had been previously. Switching to the more-expensive malathion in 1977 reduced the malaria infection rate to 3,000 by 2004. A recent study notes, "DDT and Malathion are no longer recommended since An. culicifacies and An. subpictus has been found resistant." (Malaria Journal 2005 4:8[5])

    Which also comments on the potential economic distaster that could occur:

    Uganda also began permitting its use in anti-malarial efforts despite a threat that its agricultural products to Europe could be banned if contaminated with DDT. (EU warns Uganda over plans to use DDT to fight malaria, 2005).

    and lots more.



    Maybe you could try finding out before getting mad and throwing about implied accusations? :grumpy:
     
  6. Jan 11, 2006 #5

    Mk

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    Thank you for the links and reference Hurkyl, I didn't get too mad don't worry (its not smart to get too mad in case you're wrong). So if I used DDT on my porch, would it work? Mosquitos haven't adapted to it have they? How is the DDT program in Uganda going?
     
  7. Jan 11, 2006 #6

    DocToxyn

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    The major issue with DDT isn't so much that mosquitoes have adapted to it, although they apparently have and that is nothing to scoff at. The fact is that DDT and its metabolites DDD and DDE are rather persistant in the environment and continue to have toxic effects long after their initial application. In fact you can still find measurable quantities in most animals, even in the US where DDT use was banned in 1972. DDT and its metabolites accumulate and biomagnify through the food web and eventually cause problems such as reduced reproductive success in bald eagles. The eagles were affected because they are top level predators thus exposed to high concentrations of DDT/metabolites and the toxicant altered function of a calcium transporter used in eggshell production. Once laid the eagles would actually crush their own eggs while brooding since the shells were so weak. There are numerous other examples of DDT toxicity as well.
     
  8. Jan 13, 2006 #7

    Mk

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    Yes, but... I think the masses dieing of malaria everyday are more important than cetain species of wildlife in Africa.
     
  9. Jan 13, 2006 #8

    Hurkyl

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    Until you find out that you've just made endangered the mosquito's primary predator!
     
  10. Jan 13, 2006 #9

    Moonbear

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    It's not just certain species. DDT works its way through the entire food chain, affecting aquatic species and birds the worst. And, the effects are persistent. DDT was banned in the US in 1972, and there are still residual effects now, 30 years later. So, we're not talking about a compound that can be used for a few years and then rapidly breaks down when it stops being used. It seems highly unethical to me to send a chemical to use in another country when we wouldn't be willing to use it in our own country.
     
  11. Jan 13, 2006 #10

    Mk

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    What kind of effects would it have if it was used widely in Africa?

    The United States is in a different position than say... Sudan, or Uganda.
     
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