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DDT (dichlorodiphenyltrichloroethane) is a powerful halocarbon insecticide[note 1] with a controversial history. It is an extremely stable and decay-resistant chemical: the discoverer found that jars that had contained DDT and were subsequently autoclaved[note 2] still had enough DDT residue in them to kill insects. A little goes a long way. It's also toxic, in varying degrees, to things other than insects. Its main upsides is that it is cheap to produce and rather easy to produce huge amounts of (you can basically cook your own DDT with a high school chem lab) and that it is not immediately harmful to humans in normal doses (though it is probably carcinogenic in the long run[1]). Its downsides include the development of resistances and the fact that it accumulates in fatty tissue of apex predators - like humans.

DDT use was restricted and then banned in most Western countries in the 1960s and '70s, and in those countries where it remains legal, it is only used as a health measure to control the mosquitoes that spread malaria. Only India still manufactures it. The Stockholm ConventionWikipedia was signed in 2001 to restrict the use of Persistent Organic Pollutants, of which DDT is the most well known (yes, DDT is organic — in the chemical sense of the word).

DDT bans and mass murder[edit]

[DDT] should be used with caution, only when needed, and when no other effective, safe and affordable alternatives are locally available.
—Brenda Eskenazi, explaining the scientific consensus on DDT[2]

Horrifically stupid wingnuts and experts for hire will sometimes imply that a supposed worldwide ban on DDT has killed millions of people by giving them malaria or some other mosquito-borne disease, and that Rachel Carson's book Silent Spring was responsible for the alleged ban. The myth seems to have originated from the Competitive Enterprise Institute and from libertarian Roger Bate (and is promoted by his organization Africa Fighting Malaria).

Carson devoted some of her book into weighing the pros and cons of DDT use,[3] but her findings did not lead to a global ban. DDT got banned in dozens of countries, but there was (and still is) no global ban on DDT; only agricultural use is almost globally banned. Places with deadly mosquito-borne illnesses still use DDT, and in some places excessive use has led to the development of DDT-resistant mosquitoes.[4][5] In fact, the drastic reduction of DDT use in agriculture delayed the onset of resistance in mosquitoes.

Not only is DDT still approved by the WHO for use against malaria (in indoor residual spraying,Wikipedia which is the spraying of walls of a home so a mosquito landing after it bites should get a fatal dose), but the Persistent Organic Pollutants Treaty (POPs) has a special clause for DDT.[6] Any nation may endorse the treaty calling for an end to DDT; but any nation may also use DDT at any time, for severe health reasons, by essentially writing a letter to WHO saying, "We have a health problem we think DDT may be useful to combat, so we're going to use DDT."[7]

The grain of truth beneath the bullshit[edit]

There were several aggressive — and often successful — attempts to get rid of malaria in places where it was endemic until then.[note 3] Those attempts used DDT, as it was cheap and effective, and its negative effects were not yet known or understood. While there were huge successes in the 1950s, local factors, including the premature abandoning of efforts, led to a resurgence of malaria in places where it had been significantly decreased or on the brink of extinction. By the 1970s even the WHO had to admit that the program to globally eradicate malaria had failed, even though there were some remarkable successes. However, in no case was a successful eradication program stopped due to concerns regarding DDT.

More DDT deniers[edit]

See also[edit]

External links[edit]


  1. Though one Brazilian bee Eufriesea purpurata is known to collect DDT, probably in an attempt by the males to attract females. See: Revisiting the organohalogens associated with 1979-samples of Brazilian bees (Eufriesea purpurata) and The Bees of the World, Volume 1 by Charles Duncan Michener.
  2. Brought up to a very high pressure and temperature in a specially designed device (the autoclave) and left to react.
  3. See hereWikipedia for the US example


  1. DDT, Lindane, and 2,4-D IARC Monographs on the Evaluation of Carcinogenic Risks to Humans, Volume 118 (2018) International Agency for Research on Cancer
  2. Should DDT Be Used to Combat Malaria?, Scientific American
  3. Tim Lambert, The Unending War on Rachel Carson, ScienceBlogs, May 19, 2007.
  4. The DDT story, Pesticide Action Network
  5. Rachel Carson Didn’t Kill Millions of Africans, Slate
  6. DDT Overview, Stockholm Convention
  7. Ed Darrell, in comments
  8. DDT is #1 in "The 5 Most Ridiculously Over-Hyped Health Scares of All Time" (2008), and mentioned in the "Bugs" entry of "4 Irrational Fears That Aren't as Irrational as They Seem" (2014)
  9. You pesky liberal fascists, trying to stop poison gas! And more fascism!
  10. Naomi Oreskes, Science and public policy: what's proof got to do with it?, Environmental Science & Policy, October 2004, Vol. 7, Issue 5, pp. 369-383
  11. Tim Lambert, Lomborg spreads DDT ban myth, ScienceBlogs, November 30, 2006.
  12. Townhall, enter if you dare.
  13. Google Books
  14. It's WND, so prepare your soul