Changes
DDT
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<p>In 1962, <a title="Houghton Mifflin" href="http://en.wikipedia.org/wiki/Houghton_Mifflin">Houghton Mifflin</a> published <em><a title="Silent Spring" href="http://en.wikipedia.org/wiki/Silent_Spring">Silent Spring</a></em> by American biologist <a title="Rachel Carson" href="http://en.wikipedia.org/wiki/Rachel_Carson">Rachel Carson</a>. The book catalogued the environmental impacts of the indiscriminate spraying of DDT in the US and questioned the logic of releasing large amounts of chemicals into the environment without fully understanding their effects on ecology or human health. The book suggested that DDT and other pesticides may cause <a title="Cancer" href="http://en.wikipedia.org/wiki/Cancer">cancer</a> and that their agricultural use was a threat to wildlife, particularly birds.<sup class="reference" id="_ref-Silent_Spring_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Silent_Spring">[3]</a></sup> The book resulted in a large public outcry that eventually led to DDT being banned in the US, and its publication was one of the signature events in the birth of the <a title="Environmentalism" href="http://en.wikipedia.org/wiki/Environmentalism">environmental movement</a>. DDT was subsequently banned for agricultural use worldwide, but its limited use in <a title="Vector (biology)" href="http://en.wikipedia.org/wiki/Vector_%28biology%29">disease vector</a> control continues to this day in certain parts of the world and remains controversial.</p>
<p>Along with the passage of the <a title="Endangered Species Act" href="http://en.wikipedia.org/wiki/Endangered_Species_Act">Endangered Species Act</a>, the US ban on DDT is cited by scientists as a major factor in the comeback of the <a title="Bald eagle" href="http://en.wikipedia.org/wiki/Bald_eagle">bald eagle</a> in the contiguous US.<sup class="reference" id="_ref-1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-1">[4]</a></sup></p>
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<h2><span class="editsection"></span><span class="mw-headline">History</span></h2>
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Commercial product containing 5% DDT</div>
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<p><a id="Use_in_the_1940s_and_1950s" name="Use_in_the_1940s_and_1950s"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Use in the 1940s and 1950s</span></h3>
<p>DDT is the best-known of a number of chlorine-containing <a title="Pesticide" href="http://en.wikipedia.org/wiki/Pesticide">pesticides</a> used in the 1940s and 1950s. It was used extensively during <a title="World War II" href="http://en.wikipedia.org/wiki/World_War_II">World War II</a> by Allied troops in Europe and the Pacific as well as certain civilian populations to control insect <a title="Typhus" href="http://en.wikipedia.org/wiki/Typhus">typhus</a> and malaria <a title="Vector (biology)" href="http://en.wikipedia.org/wiki/Vector_%28biology%29">vectors</a> (nearly eliminating typhus as a result). Civilian suppression used a spray on interior walls, which kills mosquitoes that rest on the wall after feeding to digest their meal; resistant strains are repelled from the area.<sup class="noprint Template-Fact"><span style="white-space: nowrap;" title="This claim needs references to reliable sources since June 2007" style="WHITE-SPACE: nowrap">[<em><a title="Wikipedia:Citing sources" href="http://en.wikipedia.org/wiki/Wikipedia:Citing_sources">citation needed</a></em>]</span></sup> Entire cities in Italy were dusted to control the typhus carried by <a title="Lice" href="http://en.wikipedia.org/wiki/Lice">lice</a>. DDT also sharply reduced the incidence of <a title="Biting midge" href="http://en.wikipedia.org/wiki/Biting_midge">biting midges</a> in Great Britain, and was used extensively as an agricultural insecticide after 1945.</p>
<p>DDT contributed to the final eradication of malaria in Europe and North America, although malaria had already been eliminated from much of the developed world in the early 20th century through the use of a range of public health measures and generally increasing health and living standards. "Malaria's decline in the United States and Europe in the late 1800s was due mainly to draining swamps and removing mill ponds". Even in countries without these advances, it was critical in their eradication of the disease. "Malaria was eradicated from <a title="Brazil" href="http://en.wikipedia.org/wiki/Brazil">Brazil</a> and <a title="Egypt" href="http://en.wikipedia.org/wiki/Egypt">Egypt</a>, largely due to extensive DDT spraying."<sup class="reference" id="_ref-4"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-4">[7]</a></sup></p>
<p>In 1955, the <a title="World Health Organization" href="http://en.wikipedia.org/wiki/World_Health_Organization">World Health Organization</a> commenced a program to eradicate malaria worldwide, relying largely on DDT. Though this program was initially highly successful worldwide (reducing mortality rates from 192 per 100,000 to a low of 7 per 100,000),<sup class="reference" id="_ref-5"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-5">[8]</a></sup> resistance soon emerged in many insect populations as a consequence of widespread agricultural use of DDT. In many areas, early victories against malaria were partially or completely reversed, and in some cases rates of transmission even increased.<sup class="reference" id="_ref-Nature81_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Nature81">[9]</a></sup></p>
<p>DDT was less effective in tropical regions due to the continuous life cycle of mosquitoes and poor infrastructure. It was not pursued at all in sub-Saharan Africa due to these perceived difficulties, with the result that mortality rates in the area were never reduced to the same dramatic extent, and now constitute the bulk of malarial deaths worldwide, especially following the resurgence of the disease as a result of microbe resistance to drug treatments and the spread of the deadly malarial variant caused by <em><a title="Plasmodium falciparum" href="http://en.wikipedia.org/wiki/Plasmodium_falciparum">Plasmodium falciparum</a></em>. The goal of eradication was abandoned in 1969, and attention was focused on controlling and treating the disease.<sup class="reference" id="_ref-6"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-6">[10]</a></sup> Spraying programs (especially using DDT) were curtailed due to concerns over safety and environmental effects, as well as problems in administrative, managerial and financial implementation. Furthermore, mosquitoes were developing resistance to DDT.<sup class="reference" id="_ref-Nature81_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Nature81">[9]</a></sup> Efforts were shifted from spraying to the use of <a titleclass="Bednetnew" classtitle="newBednet" href="http://en.wikipedia.org/w/index.php?title=Bednet&action=edit">bednets</a> impregnated with insecticides.<sup class="reference" id="_ref-7"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-7">[11]</a></sup></p>
<p><a id="Concerns_about_environmental_effects" name="Concerns_about_environmental_effects"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Concerns about environmental effects</span></h3>
<p>Concerns about DDT's environmental effects grew out of direct personal observations, usually involving a marked reduction in bird life, later supplemented by scientific investigation.<sup class="reference" id="_ref-Silent_Spring_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Silent_Spring">[3]</a></sup> The first recorded group effort against the chemical involved several citizens, including one or more scientists, in <a title="Nassau County, New York" href="http://en.wikipedia.org/wiki/Nassau_County%2C_New_York">Nassau County</a>, NY. Their unsuccessful struggle to have DDT regulated was reported in the <em><a title="New York Times" href="http://en.wikipedia.org/wiki/New_York_Times">New York Times</a></em> in 1957, and thereby came to the attention of the popular naturalist-author, <a title="Rachel Carson" href="http://en.wikipedia.org/wiki/Rachel_Carson">Rachel Carson</a>. <em><a title="New Yorker" href="http://en.wikipedia.org/wiki/New_Yorker">New Yorker</a></em> editor <a title="William Shawn" href="http://en.wikipedia.org/wiki/William_Shawn">William Shawn</a> urged her to write a piece on the subject, which developed into <em><a title="Silent Spring" href="http://en.wikipedia.org/wiki/Silent_Spring">Silent Spring</a></em>, her famous 1962 bestseller.<sup class="reference" id="_ref-8"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-8">[12]</a></sup> Despite the uproar surrounding <em>Silent Spring</em>, DDT remained in use.</p>
<p>A few years later, Carol Yannacone witnessed a fish kill at Yaphank Ponds following spraying by the Suffolk County Mosquito Control Commission. She convinced her husband <a title="Victor Yannacone" href="http://en.wikipedia.org/wiki/Victor_Yannacone">Victor Yannacone</a>, an attorney, to sue; their suit resulted in a local ban on DDT. <a class="new" title="Charles Wurster" class="new" href="http://en.wikipedia.org/w/index.php?title=Charles_Wurster&action=edit">Charles Wurster</a>, a professor at nearby <a title="State University of New York at Stony Brook" href="http://en.wikipedia.org/wiki/State_University_of_New_York_at_Stony_Brook">State University of New York at Stony Brook</a>, had earlier noticed that the use of DDT on elms in New Hampshire killed birds without saving trees.<sup class="reference" id="_ref-9"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-9">[13]</a></sup> A <a title="Bellport" href="http://en.wikipedia.org/wiki/Bellport">Bellport</a> school teacher, Art Cooley, meanwhile was observing the decline of <a title="Osprey" href="http://en.wikipedia.org/wiki/Osprey">ospreys</a> and other large birds around the <a class="new" title="Carmans River" class="new" href="http://en.wikipedia.org/w/index.php?title=Carmans_River&action=edit">Carmans River</a>, and he too correctly suspected a DDT connection—the specific effect being extremely thin and fragile shells that prevent reproduction. The Yannacones joined forces with Wurster and Cooley to form the <a title="Environmental Defense" href="http://en.wikipedia.org/wiki/Environmental_Defense">EDF</a> in 1967, and launched a wider campaign against DDT. <a title="David Peakall" href="http://en.wikipedia.org/wiki/David_Peakall">David Peakall</a> measured <a title="Dichlorodiphenyldichloroethylene" href="http://en.wikipedia.org/wiki/Dichlorodiphenyldichloroethylene">DDE</a> levels in <a title="Peregrine" href="http://en.wikipedia.org/wiki/Peregrine">Peregrine</a> eggs collected in <a title="Alaska" href="http://en.wikipedia.org/wiki/Alaska">Alaska</a> from 1969 to 1973, and showed a strong inverse relationship between DDE content and eggshell thickness. The chemical industry claimed that shell thinning occurred too rapidly after the introduction of DDT in 1946 for DDT to be the cause. Peakall filled blown peregrine eggs collected from the critical period with solvent and measured DDE in the extracted lipids. DDE was present in sufficient concentrations to account for significant eggshell thinning in 1946 in <a title="Great Britain" href="http://en.wikipedia.org/wiki/Great_Britain">Great Britain</a> and as early as 1948 in <a title="California" href="http://en.wikipedia.org/wiki/California">California</a>. Later, he would apply similar methods to <a title="California Condor" href="http://en.wikipedia.org/wiki/California_Condor">California Condor</a> eggshell fragments as evidence that this species was extremely sensitive to DDE. The efforts of this group of people eventually led to the US ban, and a spectacular recovery in once-endangered <a title="Osprey" href="http://en.wikipedia.org/wiki/Osprey">osprey</a> and eagle populations.</p>
<p><a id="Restrictions_on_usage" name="Restrictions_on_usage"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Restrictions on usage</span></h3>
<p>In the 1970s and 1980s, agricultural use of DDT was banned in most developed countries, and DDT was replaced in most antimalarial uses by less <a title="Persistent organic pollutant" href="http://en.wikipedia.org/wiki/Persistent_organic_pollutant">persistent</a>, and more expensive, alternative insecticides. DDT was first banned in <a title="Norway" href="http://en.wikipedia.org/wiki/Norway">Norway</a> and <a title="Sweden" href="http://en.wikipedia.org/wiki/Sweden">Sweden</a> in 1970 and the US in 1972, but was not banned in the <a title="United Kingdom" href="http://en.wikipedia.org/wiki/United_Kingdom">United Kingdom</a> until 1984.</p>
<p>The <a title="Stockholm Convention" href="http://en.wikipedia.org/wiki/Stockholm_Convention">Stockholm Convention</a>, ratified in 2001 and effective as of <a title="May 17" href="http://en.wikipedia.org/wiki/May_17">17 May</a> <a title="2004" href="http://en.wikipedia.org/wiki/2004">2004</a>, outlawed several <a title="Persistent organic pollutant" href="http://en.wikipedia.org/wiki/Persistent_organic_pollutant">persistent organic pollutants</a>, and restricted the use of DDT to vector control. The Convention was signed by 98 countries and is endorsed by most environmental groups. Recognizing that a total elimination of DDT use in many malaria-prone countries is currently unfeasible because there are few affordable or effective alternatives for controlling malaria, the public health use of DDT was exempted from the ban until such alternatives are developed. Regular updates on the continued need to use DDT and on global DDT production and use is available from the Stockholm Convention. <a relclass="nofollowexternal autonumber" title="http://www.pops.int/" classrel="external autonumbernofollow" href="http://www.pops.int/">[4]</a> Malaria Foundation International states:</p>
<dl><dd><em>The outcome of the treaty is arguably better than the status quo going into the negotiations over two years ago. For the first time, there is now an insecticide which is restricted to vector control only, meaning that the selection of resistant mosquitoes will be slower than before.</em><sup class="reference" id="_ref-10"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-10">[14]</a></sup></dd></dl>
<p>As of 2006, DDT continues to be used in other (primarily tropical) countries where mosquito-borne malaria and typhus are serious health problems. Use of DDT in public health to control mosquitoes is primarily done inside buildings and through inclusion in household products and selective spraying; this greatly reduces environmental damage compared to the earlier widespread use of DDT in agriculture. It also reduces the risk of resistance to DDT.<sup class="reference" id="_ref-11"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-11">[15]</a></sup> This use only requires a small fraction of that previously used in agriculture; for the whole country of <a title="Guyana" href="http://en.wikipedia.org/wiki/Guyana">Guyana</a>, covering an area of 215,000 km², the required amount is roughly equal to the amount of DDT that might previously have been used to spray 4 km² of cotton during a single growing season.<sup class="reference" id="_ref-Roberts_1997_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Roberts_1997">[16]</a></sup></p>
<p>The <a title="United States Environmental Protection Agency" href="http://en.wikipedia.org/wiki/United_States_Environmental_Protection_Agency">EPA</a> held seven months of hearings in 1971-1972, with scientists giving evidence both for and against the use of DDT. In the summer of 1972, Ruckelshaus announced a ban on most uses of DDT in the U.S., where it was classified as an EPA Toxicity Class II substance. An exemption was allowed for public health uses under some conditions, but it appears that this exemption has never been invoked. Despite the domestic ban on its use, DDT continued to be produced in the US for foreign markets until as late as 1985, when over 300,000 kg were exported.<sup class="reference" id="_ref-12"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-12">[17]</a></sup></p>
<p>The 1970s ban in the U.S. took place amid a climate of public mistrust of the scientific and industrial community, following such fiascoes as <a title="Agent Orange" href="http://en.wikipedia.org/wiki/Agent_Orange">Agent Orange</a> and use of the hormone <a title="Diethylstilbestrol" href="http://en.wikipedia.org/wiki/Diethylstilbestrol">diethylstilbestrol</a> (DES). In addition, the placement of the <a title="Bald eagle" href="http://en.wikipedia.org/wiki/Bald_eagle">bald eagle</a> on the endangered species list was also a strong factor leading to its being banned in the United States. The overuse of DDT was found to be a major factor in the bald eagle population decline, a point confirmed in later studies and in the dramatic recovery of the eagle once DDT concentrations in their food were reduced—though the claim is disputed by latter-day DDT advocates including <a title="Steven Milloy" href="http://en.wikipedia.org/wiki/Steven_Milloy">Steven Milloy</a>.<sup class="reference" id="_ref-13"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-13">[18]</a></sup></p>
<p>The ban and Carson's book have subsequently been vigorously criticized by a tiny group of pro-DDT advocates, including Steven Milloy, <a title="Roger Bate" href="http://en.wikipedia.org/wiki/Roger_Bate">Roger Bate</a> and <a title="Richard Tren" href="http://en.wikipedia.org/wiki/Richard_Tren">Richard Tren</a>, whose critiques draw on the work of the late San Jose State University entomologist <a title="J. Gordon Edwards (entomologist and mountaineer)" href="http://en.wikipedia.org/wiki/J._Gordon_Edwards_%28entomologist_and_mountaineer%29">J. Gordon Edwards</a>, a witness at the hearings who stated that there was no evidence to substantiate the claims that DDT posed a threat to human health. They report that, at the end of the hearings, hearing examiner Edmund Sweeney ruled that the scientific evidence provided no basis for banning DDT. In the summer of 1972, Ruckelshaus reviewed evidence collected during the agency's hearings as well as reports prepared by two DDT study groups (the <a class="new" title="Hilton Commission" class="new" href="http://en.wikipedia.org/w/index.php?title=Hilton_Commission&action=edit">Hilton</a> and <a class="new" title="Mark Commission" class="new" href="http://en.wikipedia.org/w/index.php?title=Mark_Commission&action=edit">Mark Commissions</a>) that had come to the opposite conclusion. Milloy and Edwards claimed that Ruckelshaus did not actually attend any of the EPA commission's hearings, and (citing unnamed aides) that he did not read any transcripts of the hearings. However, generally administrative law under both the Administrative Procedures Act and the EPA's own rules suggest the EPA director should not attend such hearings since the director would be in a position of taking administrative appeals; similar to the way the Supreme Court justices do not attend criminal arraignment hearings or criminal trials, Ruckelshaus's not attending the hearings is no problem legally. Ruckelshaus overturned Sweeney's ruling, arguing that the pesticide was "a warning that man may be exposing himself to a substance that may ultimately have a serious effect on his health."<sup class="noprint Template-Fact"><span style="white-space: nowrap;" title="This claim needs references to reliable sources since July 2007" style="WHITE-SPACE: nowrap">[<em><a title="Wikipedia:Citing sources" href="http://en.wikipedia.org/wiki/Wikipedia:Citing_sources">citation needed</a></em>]</span></sup> Ruckelshaus's action was contested by DDT manufacturers in court; had Ruckelshaus acted without sound reason, under administrative law the courts should have overturned his ruling. The court cases were decided in EPA's favor, and appeals got no traction, suggesting that Ruckelshaus's actions were solidly based on science.<sup class="noprint Template-Fact"><span style="white-space: nowrap;" title="This claim needs references to reliable sources since July 2007" style="WHITE-SPACE: nowrap">[<em><a title="Wikipedia:Citing sources" href="http://en.wikipedia.org/wiki/Wikipedia:Citing_sources">citation needed</a></em>]</span></sup></p>
<p><a id="Recent_changes" name="Recent_changes"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Recent changes</span></h3>
<h4><span class="editsection"></span><span class="mw-headline">Acute</span></h4>
<ul>
<li>DDT is classified as "moderately toxic" by the US National Toxicological Program and "moderately hazardous" by WHO.<sup class="reference" id="_ref-24"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-24">[32]</a></sup> It is not considered to be acutely toxic, and in fact it has been applied directly to clothes or used in soap.<sup class="reference" id="_ref-25"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-25">[33]</a></sup> Indeed, DDT has on rare occasions been administered orally as a treatment for <a title="Barbiturate" href="http://en.wikipedia.org/wiki/Barbiturate">barbiturate</a> poisoning.<sup class="reference" id="_ref-26"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-26">[34]</a></sup></li>
</ul>
<p><a id="Chronic" name="Chronic"></a></p>
<h4><span class="editsection"></span><span class="mw-headline">Chronic</span></h4>
<ul>
<li>Occupational exposure to DDT was associated with reduced verbal attention, visuomotor speed, sequencing, and with increased neuropsychological and psychiatric symptoms in a dose-response pattern (ie, per year of DDT application) in retired workers aged 55–70 years in Costa Rica. DDT or DDE concentrations were not determined in this study.<sup class="reference" id="_ref-27"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-27">[35]</a></sup></li> <li>In one 1969 study, 24 <a title="Cynomolgus monkey" href="http://en.wikipedia.org/wiki/Cynomolgus_monkey">cynomolgus monkeys</a> and <a title="Rhesus monkey" href="http://en.wikipedia.org/wiki/Rhesus_monkey">rhesus monkeys</a> fed 20 mg/kg of DDT for 130 months were compared to a <a title="Control group" href="http://en.wikipedia.org/wiki/Control_group">control group</a> of 17 monkeys. The study demonstrated "clear evidence of <a title="Hepatic" href="http://en.wikipedia.org/wiki/Hepatic">hepatic</a> and <a title="Central nervous system" href="http://en.wikipedia.org/wiki/Central_nervous_system">CNS</a> toxicity following long-term DDT administration." Although the exposed group developed two <a title="Malignancy" href="http://en.wikipedia.org/wiki/Malignancy">malignancies</a> and three <a title="Benign tumor" href="http://en.wikipedia.org/wiki/Benign_tumor">benign tumors</a>, compared to zero in the control group, statistically this is still "inconclusive with respect to a carcinogenic effect of DDT in nonhuman primates."<sup class="reference" id="_ref-28"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-28">[36]</a></sup></li> <li>In another study, humans voluntarily ingested 35 mg of DDT daily for about two years, and were then tracked for several years afterward. Although there was "suggestive evidence of adverse liver effects", no other adverse effects were observed.<sup class="reference" id="_ref-29"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-29">[37]</a></sup></li> <li>Farmers exposured to DDT occupationally have an increased incidence of non-allergic <a title="Asthma" href="http://en.wikipedia.org/wiki/Asthma">asthma</a>. <sup class="reference" id="_ref-30"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-30">[38]</a></sup></li>
</ul>
<p><a id="Cancer" name="Cancer"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Cancer</span></h3>
<ul>
<li>The <a title="EPA" href="http://en.wikipedia.org/wiki/EPA">EPA</a>, in 1987 , classified DDT as class B2, a <em>probable</em> human <a title="Carcinogen" href="http://en.wikipedia.org/wiki/Carcinogen">carcinogen</a> based on "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." Regarding the human carcinogenicity data, they stated "The existing epidemiological data are inadequate. Autopsy studies relating tissue levels of DDT to cancer incidence have yielded conflicting results. Three studies reported that tissue levels of DDT and DDE were higher in cancer victims than in those dying of other diseases (Casarett <em>et al.</em>, 1968; Dacre and Jennings, 1970; Wasserman <em>et al.</em>, 1976). In other studies no such relationship was seen (Maier-Bode, 1960; Robinson <em>et al.</em>, 1965; Hoffman <em>et al.</em>, 1967). Studies of occupationally exposed workers and volunteers have been of insufficient duration to be useful in assessment of the carcinogenicity of DDT to humans."<sup class="reference" id="_ref-31"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-31">[39]</a></sup></li> <li>A study of malaria workers who handled DDT occupationally found an elevated risk of cancers of the <a title="Liver" href="http://en.wikipedia.org/wiki/Liver">liver</a> and <a title="Biliary tract" href="http://en.wikipedia.org/wiki/Biliary_tract">biliary tract</a>. Another study has found a correlation between DDE and liver cancer in white men, but not for women or black men. An association between DDT exposure and <a title="Pancreatic cancer" href="http://en.wikipedia.org/wiki/Pancreatic_cancer">pancreatic cancer</a> has been demonstrated in a few studies, but other studies have found no association. Several studies have looked for associations between DDT and <a title="Multiple myeloma" href="http://en.wikipedia.org/wiki/Multiple_myeloma">multiple myeloma</a>, and testicular, prostate, endometrial, and colorectal cancers, but none conclusively demonstrated any association.<sup class="reference" id="_ref-Rogan.26Chen_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Rogan.26Chen">[40]</a></sup></li>
</ul>
<p><a id="Breast_cancer" name="Breast_cancer"></a></p>
<h4><span class="editsection"></span> <span class="mw-headline">Breast cancer</span></h4>
<p>Several studies have looked for associations between breast cancer and DDT exposure. These studies have generally measured DDT or DDE blood levels at the time of breast cancer diagnosis or after and "do not support the hypothesis that exposure to DDT is an important risk factor for breast cancer."<sup class="reference" id="_ref-EHPBreast_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-EHPBreast">[41]</a></sup> These studies have been extensively reviewed:</p>
<ul>
<li>A 2005 review in <em>The Lancet,</em> states that "[b]reast cancer has been examined most closely for an association with p, p'-DDE. In a study in 1993, 37 breast cancer patients had higher serum DDE concentrations (11.8 μg/L) than controls (7.7 μg/L), and results from several subsequent studies supported such an association. However, large epidemiological studies and subsequent pooled and meta-analyses failed to confirm the association."<sup class="reference" id="_ref-Rogan.26Chen_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Rogan.26Chen">[40]</a></sup></li>
</ul>
<ul>
<li>The journal <em>Cancer</em> more recently published a review of all of the epidemiological studies on <a title="Breast cancer" href="http://en.wikipedia.org/wiki/Breast_cancer">breast cancer</a> and DDT and DDE published between 2000 and 2006. The authors state that "Positive findings for well-controlled studies in the early 1990s of associations between breast cancer risk and the insecticide DDT, its breakdown product DDE, and PCBs prompted additional study. Snedeker reviewed studies of DDT/DDE and dieldrin, concluding that existing research strategies provided conflicting and mostly negative evidence…Updating the picture to 2006 provides…essentially unchanged conclusions for DDT/DDE." Turning their attention to the recent studies, they conclude that "A few studies show elevated risk," but "[m]ost studies did not support an association of DDE and breast cancer overall or stratified by menopausal status, tumor hormone receptor status, parity, breast-feeding, or body mass index…[I]n light of these findings, additional study of incident breast cancer in association with biological measures of DDE/DDT levels near the time of diagnosis is not a promising avenue."<sup class="reference" id="_ref-32"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-32">[42]</a></sup></li>
</ul>
<p>Recently, a study in <em>Environmental Health Perspectives</em> found a strong correlation between exposure to the <em>p,p</em>-isomer of DDT early in life and breast cancer later in life. Exposure to the <em>o,p</em>-isomer was negatively correlated with breast cancer (<em>i.e.</em> a protective effect was observed), and no association was observed for DDE. Unlike the studies discussed in the reviews cited above, this was prospective study in which blood samples were collected from young California mothers in the 1960s while DDT was still in use, and their breast cancer status was then tracked. (Most previous studies measured exposure more recently, long after DDT was banned in the US.) In addition to suggesting that exposure to the <em>p,p</em>-isomer of DDT is the more significant risk factor of breast cancer, the study also suggests that the timing of exposure is critical. For the subset of women born more than 14 years prior to the introduction of DDT into US agriculture, there was no correlation between DDT levels and breast cancer. However, for women born more recently—and thus exposed earlier in life—the most <em>p,p</em>-DDT exposed third of women had a fivefold increase in breast cancer incidence over the least exposed third, after correcting for the protective effect of <em>o,p</em>-DDT.<sup class="reference" id="_ref-EHPBreast_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-EHPBreast">[41]</a></sup><sup class="reference" id="_ref-33"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-33">[43]</a></sup></p>
<p><a id="Developmental_and_reproductive_toxicity" name="Developmental_and_reproductive_toxicity"></a></p>
<h3><span class="editsection"></span> <span class="mw-headline">Developmental and reproductive toxicity</span></h3>
<p>DDT and its breakdown product DDE, like other organochlorines, have been shown to have <a title="Estrogen" href="http://en.wikipedia.org/wiki/Estrogen">xenoestrogenic</a> activity; meaning it is chemically similar enough to estrogen to trigger hormonal responses in contaminated animals. This hormonal-mimicking activity has been observed when DDT is used in laboratory studies involving <a title="Mouse" href="http://en.wikipedia.org/wiki/Mouse">mice</a> and <a title="Rat" href="http://en.wikipedia.org/wiki/Rat">rats</a> as test <a title="Research subject" href="http://en.wikipedia.org/wiki/Research_subject">subjects</a>, and available <a title="Epidemiological" href="http://en.wikipedia.org/wiki/Epidemiological">epidemiological</a> evidence indicates that these effects may be occurring in humans as a result of DDT exposure.</p>
<ul>
<li>A review article<sup class="reference" id="_ref-Rogan.26Chen_2"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Rogan.26Chen">[40]</a></sup> in <em><a title="The Lancet" href="http://en.wikipedia.org/wiki/The_Lancet">The Lancet</a></em> concludes:</li>
</ul>
<dl><dd><em>Although DDT is generally not toxic to human beings and was banned mainly for ecological reasons, subsequent research has shown that exposure to DDT at amounts that would be needed in malaria control might cause preterm birth and early weaning, abrogating the benefit of reducing infant mortality from malaria...DDT might be useful in controlling malaria, but the evidence of its adverse effects on human health needs appropriate research on whether it achieves a favourable balance of risk versus benefit.</em></dd><dd><em><strong>Future perspectives:</strong> Although acute toxic effects are scarce, toxicological evidence shows endocrine-disrupting properties; human data also indicate possible disruption in semen quality, menstruation, gestational length, and duration of lactation. The research focus on human reproduction and development seems to be appropriate. DDT could be an effective public-health intervention that is cheap, longlasting, and effective. However, various toxic-effects that would be difficult to detect without specific study might exist and could result in substantial morbidity or mortality. Responsible use of DDT should include research programmes that would detect the most plausible forms of toxic effects as well as the documentation of benefits attributable specifically to DDT. Although this viewpoint amounts to a platitude if applied to malaria research in Africa, the research question here could be sufficiently focused and compelling, so that governments and funding agencies recognise the need to include research on all infant mortality when DDT is to be used.</em></dd></dl>
<ul>
<li>Human epidemiological studies suggest that DDT exposure is a risk factor for premature birth and low birth weight, and may harm a mother's ability to <a title="Lactation" href="http://en.wikipedia.org/wiki/Lactation">breast feed</a>. Some researchers argue that these effects may cause increases infant deaths in areas where DDT is used for malaria control, and thus offset any benefit derived from its anti-malarial effects.<sup class="reference" id="_ref-34"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-34">[44]</a></sup><sup class="reference" id="_ref-35"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-35">[45]</a></sup></li> <li>Several recent studies demonstrate a link between <em>in utero</em> exposure to DDT or DDE and <a class="new" title="Developmental neurotoxicity" class="new" href="http://en.wikipedia.org/w/index.php?title=Developmental_neurotoxicity&action=edit">developmental neurotoxicity</a> in humans. For example, a 2006 study conducted by the <a title="University of California, Berkeley" href="http://en.wikipedia.org/wiki/University_of_California%2C_Berkeley">University of California, Berkeley</a> suggests children who have been exposed to DDT while in the womb have a greater chance of experiencing development problems,<sup class="reference" id="_ref-36"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-36">[46]</a></sup> and another study from the same year found that even low-level concentrations of DDT in serum from the <a title="Umbilical cord" href="http://en.wikipedia.org/wiki/Umbilical_cord">umbilical cord</a> at birth were associated with a decrease in cognitive skills at 4 years of age.<sup class="reference" id="_ref-37"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-37">[47]</a></sup> Similarly, Mexican researchers have demonstrated a link between DDE exposure in the first trimester of pregnancy and retarded <a titleclass="Psychomotornew" classtitle="newPsychomotor" href="http://en.wikipedia.org/w/index.php?title=Psychomotor&action=edit">psychomotor</a> development.<sup class="reference" id="_ref-38"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-38">[48]</a></sup></li> <li>A 2007 study documented decreases in <a title="Semen" href="http://en.wikipedia.org/wiki/Semen">semen</a> quality among South African men from communities where DDT is used to combat endemic malaria. The researchers found statistically significant correlations between increased levels of DDT or DDE in blood plasma and decreases in several measures of semen quality including ejaculate volume, certain motility parameters, and <a title="Sperm count" href="http://en.wikipedia.org/wiki/Sperm_count">sperm count</a>.<sup class="reference" id="_ref-39"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-39">[49]</a></sup> The same researchers reported similar results in 2006 from a study of men in Mexico.<sup class="reference" id="_ref-40"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-40">[50]</a></sup> A review of earlier studies noted that "Studies of populations with a much lower exposure than that seen in current malaria-endemic areas have shown only weak, inconsistent associations between DDE and testosterone amounts, semen quality, and sperm DNA damage."<sup class="reference" id="_ref-Rogan.26Chen_3"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Rogan.26Chen">[40]</a></sup></li> <li>One recent study suggests that women exposed to DDT while in the womb have more difficulty getting pregnant as adults than non-exposed women. On the other hand, prenatal DDE exposure increased the probability of pregnancy.<sup class="reference" id="_ref-41"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-41">[51]</a></sup></li>
</ul>
<p><a id="DDT_use_against_malaria" name="DDT_use_against_malaria"></a></p>
<dl><dd><em>DDT is still one of the first and most commonly used insecticides for residual spraying, because of its low cost, high effectiveness, persistence and relative safety to humans. [...] In the past several years, we supplied DDT 75% <a title="WDP" href="http://en.wikipedia.org/wiki/WDP">WDP</a> to Madagascar, Ethiopia, Eritrea, Sudan, South Africa, Namibia, Solomon Island, Papua New Guinea, Algeria, Thailand, and Myanmar for Malaria Control project, and won a good reputation from WHO and relevant countries' government.</em><sup class="reference" id="_ref-48"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-48">[58]</a></sup></dd></dl>
<p>In the period from 1934-1955 there were 1.5 million cases of malaria in <a title="Sri Lanka" href="http://en.wikipedia.org/wiki/Sri_Lanka">Sri Lanka</a>, resulting in 80,000 deaths. After the country invested in an extensive anti-mosquito program with DDT, there were only 17 cases reported in 1963. Thereafter the program was halted, and malaria in Sri Lanka rebounded to 600,000 cases in 1968 and the first quarter of 1969. Although the country resumed spraying with DDT, many of the local mosquitoes had acquired resistance to DDT in the interim, presumably because of the continued use of DDT for crop protection, so the program was not nearly as effective as it had been before. Switching to the more-expensive <a title="Malathion" href="http://en.wikipedia.org/wiki/Malathion">malathion</a> in 1977 reduced the malaria infection rate to 3,000 by 2004. A recent study notes, "DDT and Malathion are no longer recommended since <em>An. culicifacies</em> and <em>An. subpictus</em> has been found resistant."<sup class="reference" id="_ref-49"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-49">[59]</a></sup></p>
<p>According to the <a title="Cato Institute" href="http://en.wikipedia.org/wiki/Cato_Institute">Cato Institute</a>, after <a title="South Africa" href="http://en.wikipedia.org/wiki/South_Africa">South Africa</a> stopped using DDT in 1996, the incidence of malaria in <a title="KwaZulu Natal" href="http://en.wikipedia.org/wiki/KwaZulu_Natal">KwaZulu Natal</a> province rose from 8,000 cases with 20 deaths in 1996, to 42,000 cases with 340 deaths in 2000. Today, after the reintroduction of DDT and new drug therapies, the number of deaths from malaria in the region is less than 50 per year. South Africa could afford and did try newer alternatives to DDT, but they proved less effective.<sup class="noprint Template-Fact"><span style="white-space: nowrap;" title="This claim needs references to reliable sources since July 2007" style="WHITE-SPACE: nowrap">[<em><a title="Wikipedia:Citing sources" href="http://en.wikipedia.org/wiki/Wikipedia:Citing_sources">citation needed</a></em>]</span></sup> <a title="Uganda" href="http://en.wikipedia.org/wiki/Uganda">Uganda</a> also began permitting the use of DDT in anti-malarial efforts, despite a threat that its agricultural exports to Europe could be banned if they were contaminated with DDT.<sup class="reference" id="_ref-50"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-50">[60]</a></sup> The Ugandan government has stated that it cannot achieve its development goals without first eliminating malaria. The GDP shows a striking correlation between malaria and poverty, where malaria is estimated to reduce per capita growth by 1.3 percent per annum.<sup class="reference" id="_ref-51"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-51">[61]</a></sup></p>
<p>Malaria cases increased in <a title="South America" href="http://en.wikipedia.org/wiki/South_America">South America</a> after countries in that continent stopped using DDT. Only <a title="Ecuador" href="http://en.wikipedia.org/wiki/Ecuador">Ecuador</a>, which has continued to use DDT, has seen a reduction in the number of malaria cases in recent years.<sup class="reference" id="_ref-Roberts_1997_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Roberts_1997">[16]</a></sup> Other mosquito-borne diseases are also on the rise. Until the 1970s, DDT was used to eradicate the <em><a title="Aedes aegypti" href="http://en.wikipedia.org/wiki/Aedes_aegypti">Aedes aegypti</a></em> mosquito from most tropical regions of the Americas. The reinvasion of <em>Aedes aegypti</em> since has brought devastating outbreaks of <a title="Dengue fever" href="http://en.wikipedia.org/wiki/Dengue_fever">dengue fever</a>, <a title="Dengue hemorrhagic fever" href="http://en.wikipedia.org/wiki/Dengue_hemorrhagic_fever">dengue hemorrhagic fever</a>, and a renewed threat of urban <a title="Yellow fever" href="http://en.wikipedia.org/wiki/Yellow_fever">yellow fever</a>.<sup class="reference" id="_ref-52"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-52">[62]</a></sup></p>
<p><a id="Mosquito_resistance_to_DDT" name="Mosquito_resistance_to_DDT"></a></p>
<p>In addition, DDT is not suitable for this type of spraying in Western-style <a title="Plaster" href="http://en.wikipedia.org/wiki/Plaster">plastered</a> or painted walls, only traditional dwellings with unpainted walls made of mud, sticks, <a title="Dung" href="http://en.wikipedia.org/wiki/Dung">dung</a>, thatch, <a title="Clay" href="http://en.wikipedia.org/wiki/Clay">clay</a>, or cement.<sup class="reference" id="_ref-Hargreaves_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Hargreaves">[72]</a></sup><sup class="reference" id="_ref-Thurow_2"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Thurow">[74]</a></sup><sup class="reference" id="_ref-Tren_2"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Tren">[77]</a></sup><sup class="reference" id="_ref-iea_3"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-iea">[76]</a></sup>As rural areas of South Africa become more prosperous, there is a shift towards Western style housing, leaving fewer homes suitable for DDT spraying, and necessitating the use of alternative insecticides.<sup class="reference" id="_ref-Tren_3"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Tren">[77]</a></sup></p>
<p>Other villagers object to DDT spraying because it does not kill <a title="Cockroach" href="http://en.wikipedia.org/wiki/Cockroach">cockroaches</a><sup class="reference" id="_ref-Curtis_5"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Curtis">[65]</a></sup> or <a title="Bedbug" href="http://en.wikipedia.org/wiki/Bedbug">bedbugs</a>;<sup class="reference" id="_ref-Musawenkosi_3"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Musawenkosi">[73]</a></sup> rather, it excites such pests making them more active,<sup class="reference" id="_ref-Thurow_3"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Thurow">[74]</a></sup><sup class="reference" id="_ref-Tren_4"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Tren">[77]</a></sup><sup class="reference" id="_ref-iea_4"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-iea">[76]</a></sup><sup class="reference" id="_ref-bbc_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-bbc">[75]</a></sup> so that often use of another insecticide is additionally required.<sup class="reference" id="_ref-Tren_5"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Tren">[77]</a></sup> Pyrethroids such as deltamethrin and lambdacyhalothrin, on the other hand, are more acceptable to residents because they kill these nuisance insects as well as mosquitoes.<sup class="reference" id="_ref-Curtis_6"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Curtis">[65]</a></sup></p>
<p>As a result, says Dr. <a class="new" title="Avertino Barreto" class="new" href="http://en.wikipedia.org/w/index.php?title=Avertino_Barreto&action=edit">Avertino Barreto</a>, chief of <a title="Infectious disease" href="http://en.wikipedia.org/wiki/Infectious_disease">infectious disease</a> control in <a title="Mozambique" href="http://en.wikipedia.org/wiki/Mozambique">Mozambique</a>, resistance to DDT spraying is "homegrown", not due to "pressure from environmentalists". "They only want us to use DDT on poor, rural black people," he says. "So whoever suggests DDT use, I say, 'Fine, I'll start spraying in your house first.' "<sup class="reference" id="_ref-Thurow_4"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Thurow">[74]</a></sup></p>
<p>In areas where resistance from the residents prevents a high percentage of the homes being effectively sprayed, it reduces the "chance of reaching a level of coverage at which the vectorial capacity of the mosquito population will be lowered to a point at which malaria transmission will be interrupted."<sup class="reference" id="_ref-Curtis_7"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Curtis">[65]</a></sup></p>
<p><a id="Human_exposure_associated_with_DDT_spraying_for_disease_vectors" name="Human_exposure_associated_with_DDT_spraying_for_disease_vectors"></a></p>
<p>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."</p>
</blockquote>
<p>However, the fact that DDT is not formally banned in developing nations does not necessarily mean that those nations have the option to use it. Developing nations are typically heavily dependent on aid from agencies that made the aid contingent upon non-usage of DDT. The <em>British Medical Journal</em> of March 11, 2000, reports that the use of DDT in <a title="Mozambique" href="http://en.wikipedia.org/wiki/Mozambique">Mozambique</a> "was stopped several decades ago, because 80% of the country's health budget came from donor funds, and donors refused to allow the use of DDT." <a relclass="nofollowexternal autonumber" title="http://bmj.bmjjournals.com/cgi/reprint/320/7236/669.pdf" classrel="external autonumbernofollow" href="http://bmj.bmjjournals.com/cgi/reprint/320/7236/669.pdf">[5]</a> Many African nations have been dissuaded from to using DDT in part because the European Union has said that their agricultural exports may not be accepted if spraying was "widespread."<sup class="reference" id="_ref-67"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-67">[87]</a></sup></p>
<p>According to the <a title="USAID" href="http://en.wikipedia.org/wiki/USAID">USAID</a> website, "USAID has never had a “policy” as such either “for” or “against” DDT for IRS. The real change in the past two years has been a new interest and emphasis on the use of Indoor Residual Spraying (IRS) in general – with DDT or any other insecticide – as an effective malaria prevention strategy in tropical Africa."<sup class="reference" id="_ref-68"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-68">[88]</a></sup> But the pro-DDT advocacy group <a title="Africa Fighting Malaria" href="http://en.wikipedia.org/wiki/Africa_Fighting_Malaria">Africa Fighting Malaria</a> maintains that USAID and some other international donor organizations have refused to fund public health DDT programs.<sup class="reference" id="_ref-Africa_Fighting_Malaria_FAQ_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Africa_Fighting_Malaria_FAQ">[89]</a></sup> Similarly, <a title="Roger Bate" href="http://en.wikipedia.org/wiki/Roger_Bate">Roger Bate</a> of AFM asserts that many countries have been coming under pressure from international health and environment agencies to give up DDT or face losing aid grants, and that Belize and Bolivia have gone on record to say that they gave in to pressure on this issue from the US Agency for International Development.<sup class="reference" id="_ref-69"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-69">[90]</a></sup> USAID's Kent R. Hill states that the agency has been misrepresented:</p>
<dl><dd><em>USAID strongly supports spraying as a preventative measure for malaria and will support the use of DDT when it is scientifically sound and warranted.</em><sup class="reference" id="_ref-70"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-70">[91]</a></sup></dd></dl>
<p>Before DDT, malaria was successfully eradicated or controlled in several tropical areas by removing or poisoning the breeding grounds of the mosquitoes or the aquatic habitats of the larva stages, for example by filling or applying oil to places with standing water. These methods have seen little application in Africa for more than half a century.<sup class="reference" id="_ref-72"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-72">[93]</a></sup></p>
<p>Those who advocate for increased use of DDT claim that the alternatives to DDT are generally more expensive, more toxic to humans and not always as effective at controlling malaria and insect-borne diseases, and that the petrochemical companies which patent those alternatives push(ed) for DDT's ban simply for their own profits; DDT had entered the public domain, their patented insecticides have not. Actual data on the cost-effectiveness of DDT versus other insecticides and/or means of fighting malaria is, in fact, lacking. One complicating factor is that the relative costs of various measures vary, depending on geographical location and ease of access, the habits of the particular mosquitoes prevalent in each area, the degrees of resistance to various pesticides exhibited by the mosquitoes, and the habits and compliance of the population, among other factors.</p>
<p><a title="Organophosphate" href="http://en.wikipedia.org/wiki/Organophosphate">Organophosphate</a> or <a title="Carbamate" href="http://en.wikipedia.org/wiki/Carbamate">carbamate</a> insecticides, <em>e.g.</em> <a title="Malathion" href="http://en.wikipedia.org/wiki/Malathion">malathion</a> or <a title="Bendiocarb" href="http://en.wikipedia.org/wiki/Bendiocarb">bendiocarb</a>, are considerably more expensive than DDT, and malathion requires more frequent respraying. <a title="Pyrethroid" href="http://en.wikipedia.org/wiki/Pyrethroid">Pyrethroids</a> such as <a title="Deltamethrin" href="http://en.wikipedia.org/wiki/Deltamethrin">deltamethrin</a> and <a titleclass="Lambdacyhalothrinnew" classtitle="newLambdacyhalothrin" href="http://en.wikipedia.org/w/index.php?title=Lambdacyhalothrin&action=edit">lambdacyhalothrin</a> are also more expensive than DDT, but due to their much greater coverage per unit weight, the net cost per house is about the same.<sup class="reference" id="_ref-Curtis_10"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-Curtis">[65]</a></sup></p>
<p>There are some insecticide alternatives to DDT, including <a title="Methoxychlor" href="http://en.wikipedia.org/wiki/Methoxychlor">methoxychlor</a> and <a title="Pyrethroid" href="http://en.wikipedia.org/wiki/Pyrethroid">pyrethroids</a>. The environmental and health effects of alternatives are also under scrutiny. Under the <a title="Stockholm Convention" href="http://en.wikipedia.org/wiki/Stockholm_Convention">Stockholm Convention</a>, these are issue to be addressed when investigating and promoting alternative chemicals. A recent study has found that DDT as well as <a title="Pyrethroid" href="http://en.wikipedia.org/wiki/Pyrethroid">pyrethroid</a> residues, such as <a title="Permethrin" href="http://en.wikipedia.org/wiki/Permethrin">permethrin</a> and <a title="Deltamethrin" href="http://en.wikipedia.org/wiki/Deltamethrin">deltamethrin</a>, were present in breast milk from a malaria controlled area in <a title="South Africa" href="http://en.wikipedia.org/wiki/South_Africa">South Africa</a>. The DDT was derived from malaria control, but the pattern of pyrethoid pollution indicated exposure via agricultural use, where mothers frequently work in cotton fields, as well as from domestic use of insecticide dusts in vegetable gardens.<sup class="reference" id="_ref-73"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-73">[94]</a></sup></p>
<p><a title="Vietnam" href="http://en.wikipedia.org/wiki/Vietnam">Vietnam</a> is an example of a country that has seen a continued decline in malaria cases after switching in 1991 from a poorly funded DDT-based campaign to a program based on prompt treatment, bednets, and the use of pyrethroid group insecticides. Deaths from malaria dropped by 97%.<sup class="reference" id="_ref-74"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-74">[95]</a></sup></p>
<p>In Mexico, the use of a range of effective and affordable chemical and non-chemical strategies against malaria has been so successful that the Mexican DDT manufacturing plant ceased production voluntarily, due to lack of demand.<sup class="reference" id="_ref-ddt_ipen.pdf_0"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-ddt_ipen.pdf">[96]</a></sup> Furthermore, while the increased numbers of malaria victims since DDT usage fell out of favor would, at first glance, suggest a 1:1 correlation, many other factors are known to have contributed to the rise in cases.</p>
<p>A review of fourteen studies on the subject in sub-Saharan Africa, covering insecticide-treated nets, residual spraying, chemoprophylaxis for children, chemoprophylaxis or intermittent treatment for pregnant women, a hypothetical vaccine, and changing the first line drug for treatment, found decision making limited by the gross lack of information on the costs and effects of many interventions, the very small number of cost-effectiveness analyses available, the lack of evidence on the costs and effects of packages of measures, and the problems in generalizing or comparing studies that relate to specific settings and use different methodologies and outcome measures. The two cost-effectiveness estimates of DDT residual spraying examined were not found to provide an accurate estimate of the cost-effectiveness of DDT spraying; furthermore, the resulting estimates may not be good predictors of cost-effectiveness in current programmes.<sup class="reference" id="_ref-75"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-75">[97]</a></sup></p>
<p>However, a study in Thailand found the cost per malaria case prevented of DDT spraying ($1.87 US) to be 21% greater than the cost per case prevented of <a titleclass="Lambdacyhalothrinnew" classtitle="newLambdacyhalothrin" href="http://en.wikipedia.org/w/index.php?title=Lambdacyhalothrin&action=edit">lambdacyhalothrin</a>-treated nets ($1.54 US),<sup class="reference" id="_ref-76"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-76">[98]</a></sup> at very least casting some doubt on the unexamined assumption that DDT was the most cost-effective measure to use in all cases. The director of Mexico's malaria control program finds similar results, declaring that it is 25% cheaper for Mexico to spray a house with synthetic pyrethroids than with DDT.<sup class="reference" id="_ref-ddt_ipen.pdf_1"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-ddt_ipen.pdf">[96]</a></sup> However, another study in South Africa found generally lower costs for DDT spraying than for impregnated nets.<sup class="reference" id="_ref-77"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-77">[99]</a></sup></p>
<p>A more comprehensive approach to measuring cost-effectiveness or efficacy of malarial control would not only measure the cost in dollars of the project, as well as the number of people saved, but would also take into account the negative aspects of insecticide use on human health and ecological damage. One preliminary study regarding the effect of DDT found that it is likely the detriment to human health approaches or exceeds the beneficial reductions in malarial cases, except perhaps in malarial epidemic situations. It is similar to the earlier mentioned study regarding estimated theoretical infant mortality caused by DDT and subject to the criticism also mentioned earlier.<sup class="reference" id="_ref-78"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-78">[100]</a></sup></p>
<p>A study in the Solomon Islands found that impregnated bednets cannot easily replace DDT spraying without substantial increase in incidence, but impregnated nets do permit a substantial reduction in the amount of DDT spraying.<sup class="reference" id="_ref-79"><a title="" href="http://en.wikipedia.org/wiki/DDT#_note-79">[101]</a></sup></p>
<h2><span class="editsection">S</span><span class="mw-headline">ee also</span></h2>
<ul>
<li><a title="Pesticides" href="http://en.wikipedia.org/wiki/Pesticides">pesticides</a></li> <li><a title="Agent Orange" href="http://en.wikipedia.org/wiki/Agent_Orange">Agent Orange</a></li>
</ul>
<p><a id="References" name="References"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">References</span></h2>
<ol class="references">
</ol>
<p><a id="Bibliography" name="Bibliography"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">Bibliography</span></h2>
<ul>
<li>Bailey, R. (<a title="June 12" href="http://en.wikipedia.org/wiki/June_12">12 June</a> <a title="2002" href="http://en.wikipedia.org/wiki/2002">2002</a>). <a relclass="nofollowexternal text" title="http://reason.com/rb/rb061202.shtml" classrel="external textnofollow" href="http://reason.com/rb/rb061202.shtml"><em>Silent Spring</em> at 40: Rachel Carson’s classic is not aging well</a>, <em>Reason Online</em>,</li> <li>Lundholm, C. E. (1997) DDE-induced eggshell thinning in birds: Effects of p, p'-DDE on the calcium and prostaglandin metabolism of the eggshell gland. <em>Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology</em> <strong>118</strong> (2), 113-128.</li> <li>Risebrough, R. W. (1998). <a relclass="nofollowexternal text" title="http://www.umich.edu/~esupdate/library/98.05-06/risebrough.html" classrel="external textnofollow" href="http://www.umich.edu/%7Eesupdate/library/98.05-06/risebrough.html">Endocrine Disrupters and Bald Eagles: A Response</a>.</li> <li>Roberts, D. R. (2004) <a relclass="nofollowexternal text" title="http://www.eco-imperialism.com/Roberts%20-%20Senate%20testimony%20-%20malaria.pdf" classrel="external textnofollow" href="http://www.eco-imperialism.com/Roberts%20-%20Senate%20testimony%20-%20malaria.pdf">Testimony, United States Senate, Committee on Foreign Relations</a>.</li>
</ul>
<p><a id="External_links" name="External_links"></a></p>
<h2><span class="editsection"></span><span class="mw-headline">External links</span></h2>
<div class="infobox sisterproject">
<div class="floatleft"><span><a class="image" title="Commons-logo.svg" class="image" href="http://en.wikipedia.org/wiki/Image:Commons-logo.svg"><img widthheight="67" alt="50" heightwidth="6750" border="0" src="http://upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/50px-Commons-logo.svg.png" alt="" /></a></span></div><div style="marginMARGIN-leftLEFT: 60px;">Wikimedia Commons has media related to:<div style="marginMARGIN-leftLEFT: 10px;"><em><strong><a class="extiw" title="commons:Category:DDT" class="extiw" href="http://commons.wikimedia.org/wiki/Category:DDT">DDT</a></strong></em></div>
</div>
</div>
<h3><span class="editsection"></span><span class="mw-headline">US EPA</span></h3>
<ul>
<li><a relclass="nofollowexternal text" title="http://www.epa.gov/history/topics/ddt/01.htm" classrel="external textnofollow" href="http://www.epa.gov/history/topics/ddt/01.htm">EPA press release - December 31, 1972</a></li> <li><a relclass="nofollowexternal text" title="http://www.epa.gov/history/topics/ddt/index.htm" classrel="external textnofollow" href="http://www.epa.gov/history/topics/ddt/index.htm">EPA on DDT</a></li>
</ul>
<p><a id="Toxicity_2" name="Toxicity_2"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Toxicity</span></h3>
<ul>
<li><a relclass="nofollowexternal text" title="http://www.atsdr.cdc.gov/tfacts35.html" classrel="external textnofollow" href="http://www.atsdr.cdc.gov/tfacts35.html">Agency for Toxic Substances and Disease Registry: ToxFAQs for DDT, DDE and DDD</a></li> <li><a relclass="nofollowexternal text" title="http://www.atsdr.cdc.gov/toxprofiles/tp35-c9.pdf" classrel="external textnofollow" href="http://www.atsdr.cdc.gov/toxprofiles/tp35-c9.pdf">CDC ATSDR DDT toxicity reference list (PDF)</a></li> <li><a relclass="nofollowexternal text" title="http://extoxnet.orst.edu/pips/ddt.htm" classrel="external textnofollow" href="http://extoxnet.orst.edu/pips/ddt.htm">EXTOXNET: Pesticide Information Profiles—DDT</a></li> <li><a relclass="nofollowexternal text" title="http://extoxnet.orst.edu/pips/reflist6.htm" classrel="external textnofollow" href="http://extoxnet.orst.edu/pips/reflist6.htm">Oregon State University EXTOXNET DDT toxicity reference list</a></li> <li><a relclass="nofollowexternal text" title="http://www.scorecard.org/chemical-profiles/summary.tcl?edf_substance_id=50-29-3" classrel="external textnofollow" href="http://www.scorecard.org/chemical-profiles/summary.tcl?edf_substance_id=50-29-3">Scorecard: The Pollution Information Site—DDT</a></li> <li><a relclass="nofollowexternal text" title="http://www.junkscience.com/ddtfaq.htm" classrel="external textnofollow" href="http://www.junkscience.com/ddtfaq.htm">100 things you should know about DDT</a></li>
</ul>
<p><a id="Environmental_impact_2" name="Environmental_impact_2"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Environmental impact</span></h3>
<ul>
<li><a relclass="nofollowexternal text" title="http://jan.ucc.nau.edu/doetqp/courses/env440/lectures/lec25/lec25.html" classrel="external textnofollow" href="http://jan.ucc.nau.edu/doetqp/courses/env440/lectures/lec25/lec25.html">Microbial Degradation of Pesticides</a></li> <li><a relclass="nofollowexternal text" title="http://www.fws.gov/contaminants/Info/DDTNews.html" classrel="external textnofollow" href="http://www.fws.gov/contaminants/Info/DDTNews.html">US Fish and Wildlife Service Historic News Releases - DDT</a></li> <li><a relclass="nofollowexternal text" title="http://www.inchem.org/documents/ehc/ehc/ehc83.htm" classrel="external textnofollow" href="http://www.inchem.org/documents/ehc/ehc/ehc83.htm">DDT and its Derivatives - Environmental Aspects</a></li> <li><a relclass="nofollowexternal text" title="http://umbbd.ahc.umn.edu/ddt/ddt_map.html" classrel="external textnofollow" href="http://umbbd.ahc.umn.edu/ddt/ddt_map.html">Aerobic pathway of DDT metabolization</a></li> <li><a relclass="nofollowexternal text" title="http://umbbd.ahc.umn.edu/ddt2/ddt2_map.html" classrel="external textnofollow" href="http://umbbd.ahc.umn.edu/ddt2/ddt2_map.html">Anaerobic pathway of DDT metabolization</a></li> <li><a relclass="nofollowexternal text" title="http://www.inchem.org/documents/jmpr/jmpmono/v00pr03.htm" classrel="external textnofollow" href="http://www.inchem.org/documents/jmpr/jmpmono/v00pr03.htm">Pesticide residues in food 2000 : DDT</a></li> <li><a relclass="nofollowexternal text" title="http://www.inchem.org/documents/jmpr/jmpmono/v84pr49.htm" classrel="external textnofollow" href="http://www.inchem.org/documents/jmpr/jmpmono/v84pr49.htm">Pesticide residues in food—1984</a></li> <li><a relclass="nofollowexternal text" title="http://www.ces.clemson.edu/ees/lee/organochlorines.html" classrel="external textnofollow" href="http://www.ces.clemson.edu/ees/lee/organochlorines.html">Environmental Fate Evaluation of DDT, Chlordane and Lindane</a></li> <li><a relclass="nofollowexternal text" title="http://www.epa.gov/history/publications/formative6.htm" classrel="external textnofollow" href="http://www.epa.gov/history/publications/formative6.htm">EPA: Pesticides and Public Health</a></li>
</ul>
<p><a id="Articles_in_political_magazines" name="Articles_in_political_magazines"></a></p>
<h4><span class="editsection"></span><span class="mw-headline">Articles in political magazines</span></h4>
<ul>
<li><a relclass="nofollowexternal text" title="http://www.reason.com/rb/rb010704.shtml" classrel="external textnofollow" href="http://www.reason.com/rb/rb010704.shtml">DDT, Eggshells, and Me</a> Article from <a title="Reason magazine" href="http://en.wikipedia.org/wiki/Reason_magazine">Reason magazine</a></li> <li><a relclass="nofollowexternal text" title="http://www.frontpagemag.com/Articles/ReadArticle.asp?ID=23262" classrel="external textnofollow" href="http://www.frontpagemag.com/Articles/ReadArticle.asp?ID=23262">DDT: The Bald Eagle Lie</a> Article from <a title="FrontPageMag.com" href="http://en.wikipedia.org/wiki/FrontPageMag.com">FrontPageMag.com</a></li>
</ul>
<p><a id="Malaria_and_DDT" name="Malaria_and_DDT"></a></p>
<h3><span class="editsection"></span><span class="mw-headline">Malaria and DDT</span></h3>
<ul>
<li><a relclass="nofollowexternal text" title="http://www.washingtonpost.com/wp-dyn/content/article/2005/06/04/AR2005060400130.html" classrel="external textnofollow" href="http://www.washingtonpost.com/wp-dyn/content/article/2005/06/04/AR2005060400130.html">"If Malaria's the Problem, DDT's Not the Only Answer"</a>, a <em><a title="Washington Post" href="http://en.wikipedia.org/wiki/Washington_Post">Washington Post</a></em> column by <a title="Entomologist" href="http://en.wikipedia.org/wiki/Entomologist">entomologist</a> May Berenbaum</li> <li><a relclass="nofollowexternal text" title="http://www.who.int/mediacentre/news/releases/2006/pr50/en/index.html" classrel="external textnofollow" href="http://www.who.int/mediacentre/news/releases/2006/pr50/en/index.html">WHO gives indoor use of DDT a clean bill of health for controlling malaria</a> The current position of the <a title="World Health Organization" href="http://en.wikipedia.org/wiki/World_Health_Organization">World Health Organization</a></li> <li><a relclass="nofollowexternal text" title="http://www.gladwell.com/2001/2001_07_02_a_ddt.htm" classrel="external textnofollow" href="http://www.gladwell.com/2001/2001_07_02_a_ddt.htm">"The Mosquito Killer"</a>, a <em><a title="The New Yorker" href="http://en.wikipedia.org/wiki/The_New_Yorker">New Yorker</a></em> article about <a title="Fred Soper" href="http://en.wikipedia.org/wiki/Fred_Soper">Fred Soper</a> by <a title="Malcolm Gladwell" href="http://en.wikipedia.org/wiki/Malcolm_Gladwell">Malcolm Gladwell</a></li> <li><a relclass="nofollowexternal text" title="http://www.vega.org.uk/video/programme/87" classrel="external textnofollow" href="http://www.vega.org.uk/video/programme/87">'Andrew Spielman, Harvard School of Public Health, discusses environmentally friendly control of Malaria and uses of DDT</a> Freeview video provided by the Vega Science Trust</li> <li><a relclass="nofollowexternal text" title="http://info-pollution.com/ddtban.htm" classrel="external textnofollow" href="http://info-pollution.com/ddtban.htm">The DDT ban myth</a></li> <li><a relclass="nofollowexternal text" title="http://www.iea.org.uk/files/upld-publication26pdf?.pdf" classrel="external textnofollow" href="http://www.iea.org.uk/files/upld-publication26pdf?.pdf">Malaria and the DDT Story</a></li> <li><a relclass="nofollowexternal text" title="http://www.sourcewatch.org/index.php?title=Malaria_and_DDT" classrel="external textnofollow" href="http://www.sourcewatch.org/index.php?title=Malaria_and_DDT">Malaria and DDT</a></li> <li><a relclass="nofollowexternal text" title="http://kenethmiles.blogspot.com/2004_02_01_kenethmiles_archive.html#107570569615970184" classrel="external textnofollow" href="http://kenethmiles.blogspot.com/2004_02_01_kenethmiles_archive.html#107570569615970184">Putting Myths to Bed</a></li> <li>The <a relclass="nofollowexternal text" title="http://www.fightingmalaria.org/news.php?ID=575" classrel="external textnofollow" href="http://www.fightingmalaria.org/news.php?ID=575">Kill Malarial Mosquitoes NOW!</a> coalition, a project of the international <a title="NGO" href="http://en.wikipedia.org/wiki/NGO">NGO</a> <a title="Africa Fighting Malaria" href="http://en.wikipedia.org/wiki/Africa_Fighting_Malaria">Africa Fighting Malaria</a></li> <li><a relclass="nofollowexternal text" title="http://timlambert.org/2005/12/ddt-ban-myth-bingo/" classrel="external textnofollow" href="http://timlambert.org/2005/12/ddt-ban-myth-bingo/">DDT Ban Myth Bingo</a></li> <li><a relclass="nofollowexternal text" title="http://www.globalisationinstitute.org/blog/misc/nets-for-fighting-malaria-20051103120/" classrel="external textnofollow" href="http://www.globalisationinstitute.org/blog/misc/nets-for-fighting-malaria-20051103120/">Nets for fighting malaria</a></li>
</ul>