Kristin S. Schafer, Pesticide Action Network, 29 November 2006

DDT is in the news again, promoted by a handful of aggressive advocates as a silver bullet solution to malaria in Africa. The DDT promoters' story goes something like this:

"Malaria is killing people in Africa, but environmentalists care more about saving birds and are blocking the use of DDT to save people. DDT wiped out malaria in the U.S., but is now being denied to Africans. DDT is the best way to fight malaria. There are no heath effects from DDT exposure, and its use should be widespread."

The only accurate part of this story is that malaria does kill millions of people in Africa every year, a preventable public health tragedy of catastrophic proportions. The rest of the story is false, but it is being pitched aggressively and effectively by well-funded sources to mainstream media outlets and members of Congress. A New York Times columnist even titled a recent article "What the World Needs Now is DDT." [1]

"DDT is a short-sighted response with long term consequences," says Paul Saoke, M.D., Director of Physicians for Social Responsibility in Kenya. "While it may be effective in some cases where mosquitoes haven't yet developed resistance, it won't solve the malaria health crisis. Technical expertise and better malaria control methods already exist in Africa. It's only resources and political will that are lacking."

Public health experts, government officials and environmentalists around the world support the approach to DDT taken by the Stockholm Convention on Persistent Organic Pollutants (POPs). The treaty targets DDT (along with eleven other dangerous chemicals) for global phase out, but allows exemptions for malaria control in countries that request it. This approach recognizes that in some cases, DDT can be an effective temporary tool for malaria control. Most importantly, the treaty also mobilizes desperately needed funds for malaria control and prevention, with an emphasis on safer, more effective strategies that don't further jeopardize the health of current and future generations.

Here are some basic facts to dispel the new myths about DDT:

DDT Promoters' myth: "DDT wiped out malaria in the U.S."

Fact: Malaria had been largely eliminated in the U.S. by the time the Centers for Disease Control (CDC) first used DDT in spray campaigns in 1947. CDC's four-year spray effort was designed to prevent the reintroduction of malaria from troops coming home from World War II. Almost twnety years earlier, in 1928, the Public Health Service had already noted the decline of malaria in the U.S. [2] The pockets that persisted in the South until the late 1930s were controlled by the Tennessee Valley Authority's efforts to cut down on mosquito breeding sites by draining swamps and protect the population by building well-screened houses. [3] According to one journalist investigating the issue, "About the best one CDC physician involved in the campaign could say about it was that 'we kicked a dying dog.'"

DDT Promoters' myth: "DDT only hurts birds, not people."

Fact: Both human health and the environmental impacts led to the 1972 DDT ban in the U.S., and we know even more today about DDT's human health effects than we did back then. DDT is classified by U.S. and international authorities as a "probable" human carcinogen, [5] and exposure is linked to human developmental disorders. Reproductive disorders associated with DDT are well documented in animal studies. [6] Recent studies have also linked DDT exposure to reduced breastmilk production among nursing women, [7] and U.S. researchers have found that the DDT breakdown product, DDE, is associated with increased risks of premature delivery and reduced infant birth weight. [8] DDT and its breakdown products have also been found in human blood and breastmilk in dozens of studies around the world. [9]

DDT Promoters' myth: "DDT is the best tool to fight malaria."

Fact: The World Health Organization (WHO) tried to eradicate malaria worldwide with a massive DDT spray program in the 1950s and 60s. While the program helped to control malaria in many places, wiping out malaria with DDT was an unrealistic goal that could not be met. One of the many reasons for the failure of this ambitious effort was resistance to DDT among malaria-carrying mosquitoes. Resistance was identified in Africa as early as 1955, and by 1972 nineteen species of mosquito worldwide were resistant to DDT. [10] Often DDT intended for public health use is diverted to illegal agricultural use, hastening the development of resistant mosquito populations. More effective and safer approaches to malaria control are now being used in many countries. For example, Mexico uses an integrated approach that combines: a) early detection of malaria cases and prompt medical treatment, b) community participation in notification of malaria cases and cleaning of streams and other sites where mosquitoes breed; and c) low-volume chemical control with pyrethroid pesticides. [11]

DDT Promoters' myth: "DDT use for malaria control is completely harmless."

Fact: When DDT is used for malaria control, it is usually sprayed on the walls inside homes, so risk of exposure is very high. Researchers in Mexico and South Africa found elevated levels of DDT in the blood of those living where DDT was used to control malaria, and breast-fed children in those areas received more DDT than the amount considered "safe" by WHO and the U.N. Food and Agricultural Organization (FAO). [12] Evidence also shows that long-lasting residues from DDT house spraying seep into nearby waterways, creating additional pathways of exposure. For example, elevated DDT levels have been found in cow's milk in indoor DDT treatment areas. [13] In many countries, this adds to exposure from old stockpiles of DDT that are not properly contained or controlled. FAO estimates there are more than 100,000 tons of obsolete pesticide stockpiles in Africa, mostly older chemicals such as DDT. [14]

DDT Promoters' myth: "All countries with malaria need DDT."

Fact: Many countries are controlling malaria with effective alternative approaches. Vietnam reduced malaria deaths by 97% and malaria cases by 59% when they switched in 1991 from trying to eradicate malaria using DDT to a DDT-free malaria control program involving distribution of drugs and mosquito nets along with widespread health education organized with village leaders.[15] A program in the central region of Kenya is focusing on reducing malaria by working with the rice growing community to improve water management, use livestock as bait, introduce biological controls and distribute mosquito nets in affected areas. [16]The World Wildlife Fund has documented success in the Kheda district in India, where non-chemical approaches were demonstrated to be cost-effective. [17] In the Philippines, the successful national program has relied on treated bed nets and spraying of alternative chemicals. [18] What countries fighting malaria need is strong support for effective solutions, not increased reliance on DDT.

DDT Promoters' myth: "DDT is being denied to those who need it most."

Fact: The few countries that still do need to use DDT to control malaria are able to obtain it. Eighteen of the fifty-four countries in Africa have requested an exemption under the Stockholm Convention for DDT use for malaria control, and an estimated eleven of these are currently using DDT. [19] [20] The Stockholm Convention calls for the ultimate elimination of DDT as soon as these countries are satisfied that alternatives are workable for their specific needs. [21] This approach is supported by public health experts and governments around the world, together with those in the environmental, development and public interest communities in virtually all countries.

DDT Promoters' myth: "Millions of people will die without DDT."

Fact: Millions of people are dying now and will continue to die without effective malaria control. In a handful of countries, this may still include spraying with DDT in the short term, until more effective controls are in place. The public health community learned long ago not to rely on any single solution in fighting this deadly disease, with failed reliance on DDT providing the original lesson. Fortunately, experiences in Vietnam, Ethiopia, Mexico, the Philippines and other countries show that effective malaria control is possible, and that it requires a real commitment of resources, integrated strategies and community participation.

Clearly, what the world needs now is not more DDT. If we're serious about fighting malaria, what we need is realistic long-term funding for community-based control strategies combined with improved housing, basic sanitation and effective policies to fight poverty. It's true that this more genuine solution is more complicated than spraying a "quick, cheap and dirty" silver-bullet chemical from a by-gone era. But it will also save more lives and provide long term malaria control, which DDT cannot.

((Note from Spinwatch: The original article on the PANNA-website also has a sidebar, listing important promotors of DDT. On the same website also an update on the WHO-decision is to be found)

References

1. Rosenberg, T. April 11, 2004. "What the World Needs Now is DDT," New York Times. See link

2. Centers for Disease Control and Prevention. April 2004. The History of Malaria, an Ancient Disease. http://www.cdc.gov/malaria/history/index.htm.

3. The New Deal Network. 2003. The Tennessee Valley Authority: Electricity for All. See http://newdeal.feri.org/tva/ .

4. Shah, S. April 2006. Don't Blame Environmentalists for Malaria. The Nation. http://www.thenation.com/doc/20060417/shah.

5. DDT is classified as "reasonably anticipated to be a human carcinogen" U.S. Department of Health and Human Services, Public Health Service, National Toxicology Program. January 2001. Ninth Report on Carcinogens. Available at http://ehis.niehs.nih.gov/roc/ninth/rahc/ddt.pdf ;

DDT falls into Group 2B ("possibly carcinogenic to humans") under the IARC Carcinogenicity Classification scheme in Overall Evaluations of Carcinogenicity to Humans, compiled from IARC Monographs Vol. 1-79, available online at http://193.51.164.11/monoeval/crthall.html

6. Agency for Toxic Substances and Disease Registry. September 2000. Toxicological Profile for DDT, DDE, DDD: Draft for Public Comment. Atlanta, GA. http://atsdr1.atsdr.cdc.gov/toxprofiles/tp35.html. Also

Orris, P. et. al. May 2000. Persistent Organic Pollutants and Human Health. World Federation of Public Health Associations, USA.

7. Gladen, B.C. and Rogan, W.J. 1995. DDE and Shortened Duration of Lactation in a Northern Mexican Town. Am J Public Health, vol 85: 504-08

8. Longnecker, M.P. et.al. 2001. Association between maternal serum concentration of the DDT metabolite DDE and preterm and small-for-gestational-age babies at birth. The Lancet, vol. 358: 110-114.

See also Rogan et.al. 2005. Health Risks and Benefits of bi (4-chlorphenyl) 1,1,1-trichloroethane (DDT). Lancet, 366: 763-73.

9. For a comprehensive overview of studies finding DDT in breastmilk, see http://www.nrdc.org/breastmilk.

See also Centers for Disease Control and Prevention. July 2005. Third National Report on Human Exposure to Environmental Chemicals. See http://www.cdc.gov/exposurereport/.

10. Berenbaum, M. June 5, 2005. If Malaria's the Problem, DDT's Not the Only Answer. Washington Post. 

11. Bejarano, F.G. 2001. The Phasing Out of DDT in Mexico. Pesticide Safety News, vol. 5, no. 2:5. International Center for Pesticide Safety, Milan, Italy.

and Centro Nacional de Salud Ambiental. Diciembre 2000. Situacion actual de la malaria y uso del DDT in Mexico. Centro de Vigilancia Epidemiologica. Secreteria de Salud;

and RAPAM. World Wildlife Fund. Julio 1998. Participación ciudadana y alternativas al DDT para el control del la malaria. Memorias. Texcoco, México.

12. Waliszewski S.M., et.al. 1996. Organochlorine pesticide residues in human breast milk from tropical areas in Mexico, Bull Environ Contam Toxicol 57:22-28

13. ibid

14. UN Food and Agriculture Organization. 2001.Baseline Study on the Problem of Obsolete Pesticide Stocks. FAO Pesticide Disposal Series, No.9. See link

15. World Health Organization. 2000. A Story to be Shared: The Successful Fight Against Malaria in Vietnam. See http://www.afronets.org/files/malaria.pdf.

16. International Development Research Center. 2003. Malaria and Agriculture in Kenya : A New Perspective with Links between Health and Ecosystems. Case Study: Health and Ecosystem Approach. See http://www.idrc.ca/uploads/user-S/10530071320Ecohealth_2_Kenya_e.pdf.

17. World Wildlife Fund. 1998. Resolving the DDT Dilemma: Protecting Biodiversity and Human Health. See http://assets.panda.org/downloads/resolvingddt.pdf.

18. Government of India. National Malaria Control Program 1999: Country Scenario.

and P.C. Matteson, The Philippine National Malaria Control Program, in P.C. Matteson. 1998. (ed). Disease Vector Management for Public Health and Conservation. World Wildlife Fund, Washington, DC.

19. Daniel K. May 22, 2006. Uganda : Traders' Chief Warns on DDT Use. East Africa Business Week. http://allafrica.com/stories/200605240305.html

20. UNEP, "Revised List of Requests for Specific Exemptions in Annex A and Annex B and Acceptable Purposes in Annex B Received by the Secretariat Prior to the Commencement of the Conference of the Plenipotentiaries on 22 May 2001," UNEP/POPS/CONF/INF/1/Rev.3. See link

21. Stockholm Convention on Persistent Organic Pollutants (POPs), Annex B (Restriction), Part II, para. 1-7. Treaty text available online at http://www.pops.int