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DDT to Return as Weapon Against Malaria, Experts Say

Brian Handwerk

for National Geographic News

August 1, 2006

http://news.nationalgeographic.com/news/2006/08/060801-ddt-malaria.html

DDT, a notorious symbol of environmental degradation, is poised to make a comeback.

 

International experts are touting the widely banned pesticide as a best bet to save millions of human lives threatened by malaria.

 

The disease, which kills mostly children and pregnant women, is largely spread by mosquitoes.

 

The overwhelming majority—90 percent—of malaria victims live in Africa, where the disease plagues both human and economic health (Africa facts, maps, more).

 

In May the U.S. Agency for International Development (USAID) endorsed the use of DDT for indoor antimalarial treatment in the developing world.

 

The World Health Organization (WHO) is expected to do the same in short order, according to a comprehensive report published in the current issue of the journal Nature Medicine.

 

Thirty years ago I and many others fought fought to get DDT banned.

It was mild in compared to many other chlorinated hydrocarbons.

Then I had read Rachel Carson's "Silent Spring" and the even better book by? called "Since Silent Spring" which tells of the story of how Big Corporations and money tried to discredit Rachel Carson.

Few seem to remember any of this now. It seems big corporations just wait for the fuss and memory to die down and then re-introduce things like DDT and Thalidomide (now being marketed in S. America). While everyone assumes that that environmental battle has been won.

Many environmental books state "DDT has been banned". Perhaps, it has, in some counries. But spraying in any one part of the world spreads DDT all over the planet; just like greenhouse gasses.

 

I didn't know weather to put this thread in environment or medical ; but as the DDT is for a medical use (anti-malaria) i thought I would put it here. Of course there are as many environmental consequences of using DDT as there are medical

 

I wanted to state my position when starting this thread as the UN is now using and advocating its use to control the Malaria mosquito.

 

What do you think?

The debate is hotting up here are a few articles from different sides of the fence

 

http://www.newvision.co.ug/D/8/459/508890

The truth about malaria and DDT

By Guest: Paul Driessen on Jul 17, 2006

http://newsbyus.com/more.php?id=4486_0_1_0_M

Inaccurate claims about DDT are killing African children. People need to learn the facts.

 

Malaria continues to be the biggest single killer of African children. However, years of effort to improve malaria control programs are finally bearing fruit.

 

 

Archbishop Desmond Tutu, Greenpeace co-founder Patrick Moore, and hundreds of physicians, clergy and human rights advocates signed the Kill Malarial Mosquitoes NOW declaration, demanding that substantial funds be spent on indoor spraying with DDT,

 

Rural mothers have DDT in breast milk - study

Melanie Gosling

July 24 2006 at 04:56AM

http://www.iol.co.za/index.php?set_id=14&click_id=14&art_id=vn20060724003819434C666973

A study has found mothers tested in rural areas have pesticides, including DDT, in their breast milk.

 

Some of the women had 77 times the international limit for DDT residue in humans, while in some of the babies it was 12 times the World Health Organisation's acceptable daily intake.

 

These shock findings emerged as a new US study shows DDT in mothers is linked to delays in physical and mental development. The study is one of the first to link DDT with human developmental problems.

 

Banned in most countries because of its harmful effects on the environment, DDT is used in some parts of South Africa to kill malaria mosquitoes.

http://patient.cancerconsultants.com/news.aspx?id=37668

DDT Exposure Linked to Increased Rates of Liver Cancer

 

According to an article recently published in the Journal of the National Cancer Institute, the pesticide known as DDT (1,1,1-Trichloro-2,2-bis(p-chlorophenyl) ethane) appears to significantly increase the risk of developing cancers that originate in the liver.

I will sue Lukyamuzi over DDT � Tumwine

Monday, 24th July, 2006

http://www.newvision.co.ug/D/8/13/511216

Ken Lukyamuzi

 

By Esther Alalo

 

COURT Martial chief Gen. Elly Tumwine has vowed to sue Ken Lukyamuzi (right), accusing him of spreading lies on the use of DDT to eradicate malaria.

 

He said the Conservative Party (CP) chief had caused fear among the populace, preventing the Government from using DDT to save lives.

 

�Over 320 Ugandans die of malaria daily and about 120,000 annually and people like Lukyamuzi are discouraging the Government from using DDT. I will sue him,� he said.

 

Environmentalists have discouraged the use of DDT (dichlorodiphenyltrichloet-hane) in eradicating malaria, saying it is harmful to human health.

 

Tumwine said the western world was discouraging DDT use to ensure that Africans continue suffering and seeking foreign aid.

 

�Countries like South Africa, Mozambique and Zimbabwe are using DDT and they have been successful in eradicating malaria,� Tumwine said.

 

Tumwine said DDT had been used in the past but there was no evidence that it had harmed humans.

 

.

 

Tumwine said the ban on the use of DDT was politically-motivated.

 

DDT will harm our organic agricultural exports

Wednesday, 12th July, 2006

E-mail article E-mail article Print article Print article

Daniel Lukwago

 

Daniel Lukwago

 

Uganda is one of the Sub Sahara African countries with the greatest potential for organic farming because of her comparative advantage of having pollution free environment.

Through promotion of organic farming, small-holder farmers can learn the organic equivalents and apply them to raise productivity and quality of output for sale at premium prices, raising their incomes and reducing poverty. A good example is the organically grown cotton grown in Lira is sold to Phoenix in Uganda and exported to China with genuine organic label.

However, use of DDT against mosquitoes can adversely affect the country�s organic farming potential.

http://www.newvision.co.ug/D/8/459/508890

--

Michael

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Here in Taiwan malaria is said to be totally eradicated....they are still using ddt...

 

I am persnally against it. it is forcing bad health on people who dont want it. if you dont want malaria, take some steps to avoid mosquitos. there are far less harmfull methods.

 

look at this it is a great, cheap home made mosquito trap.

http://forums.permaculture.org.au/viewtopic.php?p=19180#19180

 

http://www.capetimes.co.za/index.php?fSectionId=330&fArticleId=3356407

DDT dilemma

July 26, 2006

 

By the Editor

 

It was Rachel Carson's 1960s book Silent Spring that shocked the world about the damaging effects of DDT on the environment.

 

Hailed initially as a wonder pesticide because of its apparent non-toxic effects on humans, the lethal effects of DDT emerged many years later.

 

DDT stays in the environment for decades and is transported over huge distances by water and air. It is even found in the remote Antarctic.

 

It is stored in fatty tissues and is taken up in the food chain. It is in breast milk, in livestock and in food all over the world. It is highly toxic to fish and to birds. There is a possible link between DDT and the risk of breast cancer, and evidence suggests it may suppress the immune system.

 

Research in the United States has found that DDT is linked to delays in babies' physical and mental development. Some women in KwaZulu-Natal have up to 77 times more DDT in their breast milk than the international safe limit, while their babies have 12 times the limit.

 

Many countries banned DDT decades ago. Countries that signed the United Nations' Stockholm Convention have committed themselves to eliminating DDT by 2025.

 

But because DDT is an effective and cheap way of killing malaria mosquitoes, the convention allows its use until an alternative is found.

South Africa has been using DDT this way for over a decade.

 

But as a signatory to the convention, South Africa is obliged to promote development to find safe alternatives.

If the departments of health or of science and technology have made advances in this field, they are keeping them quiet.

 

A worrying fact is that local scientists say they are battling to get funding to study the effects of DDT on people. Even more disturbing is their claim that funding is deliberately blocked.

 

Malaria is a killer, and it is understandable that a country will use whatever it can to save lives now.

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1.3 Rationale

 

DDT is a persistent, broad spectrum pesticide that in the past has been widely used in agriculture and for the control of mosquitoes, black flies and other insect pests and disease vectors. Some developing countries still use it in malaria campaigns, not only because of its effectiveness, but also because of its low cost and lack of acute toxicity for applicators, compared to alternative chemical pesticides that are more costly or more toxic. However, DDT and its metabolites are persistent, bioaccumulative and can be transported long distances through the atmosphere. Residues of DDT and its metabolites in the environment have been shown to result in adverse effects on wildlife reproduction.

 

http://www.cec.org/programs_projects/pollutants_health/smoc/ddt.cfm?varlan=english

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Scientists call for continued use of DDT

 

Thursday, 23 November 2000

 

Anopheles mosquito

A female Anopheles mosquito biting a malaria infected human. Pic: The Walter and Eliza Hall Institute of Medical Research

Tropical disease scientists around the world have intensified calls for governments not to ban the use of DDT, because malaria rates are climbing in countries which have stopped using the pesticide.

 

About 2.5 million people die from malaria annually, but deaths will increase if some countries stop using the pesticide, according to Donald Roberts, a professor of tropical public health at the Uniformed Services University of Health Sciences, Maryland.

 

http://www.abc.net.au/science/news/stories/s215291.htm

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it is quite the dilema for sure...but in countries that (although maybe not developed like australia, canada or england) are really rich and hav things like goo health programs and especially countries that claim to have eliminated ddt should not really be using this. it is still used mainly to control annoyances and crop damage.

 

i sure fricking hope my babies dont come out buggered from living here:evil: .....dont think its THAT common here though.

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it is quite the dilema for sure...but in countries that (although maybe not developed like australia, canada or england) are really rich and hav things like goo health programs and especially countries that claim to have eliminated ddt should not really be using this. it is still used mainly to control annoyances and crop damage.

 

i sure fricking hope my babies dont come out buggered from living here:evil: .....don't think its THAT common here though.

 

In Australia we don't have to worry about Maleria. (We do have Ross river Fever; carried by mosquitoes) So we don't have to watch children die of malaria which might change your opinion of whether DDT should be used.

My contention is that developed counties should fork out the extra money to buy safer pesticides (like neem and pyrethrum) and traps;- as DDT spraying in Africa effects the whole planet.

 

I am amazed it is still used in Malaysia. Of course it is only one of many chlorinated hydrocarbons.

 

One problem rarely mentioned it that CHs spread out and float on the top micron of the water and interfere with the health and reproductive capacity of photo plankton -our major source of Oxygen.

This is interesting on phytoplankton

http://www.deh.gov.au/coasts/publications/somer/annex1/phytoplankton.html

Sensitivity of phytoplankton to chemical pollutants

Chemical pollutants, including both organic and inorganic compounds, can cause selective inhibition of phytoplankton species, with wide ranging effects at higher trophic levels.

Chlorinated organics, including DDT, dieldrin, chlordane, polychlorinated biphenyls (PCBs) and chlorophenols, are of particular concern because they readily absorb to particulates and sediments, are resistant to degradation and have the potential to bioaccumulate. PCB levels (1-10 mg per l) have been reported in Botany Bay and Port Phillip Bay, and may depress the growth of sensitive diatoms (Fisher & Wurster 1973). . .

Some of the chlorophenolic compounds, such as the more substituted chlorocatechols, are toxic to freshwater algae and marine diatoms (Kuivasniemi, Eloranta & Knuutinen 1985), with chlorate being particularly toxic to phytoplankton.

 

--

l

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Gourevitch states that only India manufactures DDT. He's wrong. China also produces (and uses) DDT. While India uses the DDT it produces domestically, the malaria program managers I've spoken with elsewhere say that India produces such poor quality DDT that they won't buy it.

 

I should mention here that WWF has been supporting South Africa's use of DDT for malaria control because effective alternatives were not available. When alternative sprays were tried, malaria incidence and deaths went up and when South Africa returned to DDT, malaria incidence and deaths went down. There are approximately 24 countries in the world now using DDT. Just under half are in Africa, in southern Africa and the horn of Africa. DDT is not used throughout Central and West Africa.

 

Many thanks to Rich Liroff for reviewing this atrocious article. Contact: [email protected]

http://www.mindfully.org/Pesticide/2003/DDT-Save-AfricansMar03.htm

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A pro report

http://news.nationalgeographic.com/news/2006/08/060801-ddt-malaria_2.html.

How spraying the insides of houses is less a problem, to humans, than spraying fields is a moot point?

"For duration of activity there is no [competitive] chemical that even comes close to DDT, and of course the duration is a big factor in overall cost," Roberts, of Uniformed Services University, said.

 

"If you're spraying one time versus four times a year, the cost difference is enormous."

 

Cost is critical, because malaria typically affects the poorest of the poor—lower-income people in developing nations.

 

DDT also packs a dual-threat capability: It not only kills mosquitoes outright, but it also works as a repellent.

 

"[Treating house walls] is a perimeter treatment," Roberts explained. "The people you're trying to protect are on the inside of the perimeter, so mosquitoes will come up to that wall, detect the DDT in the vapor phase, and move away from it," Roberts said.

 

Environmental organizations such as the Sierra Club have acknowledged the chemical's usefulness in saving human life.

 

"We have not opposed the use of DDT to fight malaria in developing countries," said Ed Hopkins, director of the Sierra Club's environmental quality program.

 

"Obviously malaria is a serious disease and a public health threat in developing countries. Local public health authorities are in the best position to decide if their countries need to use DDT to fight malaria.

 

"This is a relatively minor use of DDT compared with agricultural uses," he continued.

 

"We think it's important for developing countries to be able to protect the health of their citizens, but not to use vast amounts of DDT for growing crops when there are safer alternatives available."

 

Some experts caution that once the chemical is revived in quantity, DDT may be put to use—or misuse—in agriculture. Robust monitoring will be key to limiting its potential negative effects.

 

Managing DDT's application to account for insect resistance is another challenge.

 

Insects are remarkably adaptable, so use of DDT must be carefully monitored and controlled to ensure that the treatments don't enhance insects' genetic DDT resistance.

 

Despite the potential roadblocks, many health officials have brightened at the prospect of the pesticide's disease-fighting power.

 

Arata Kochi, director of WHO's Global Malaria Program, is one supporter.

 

"Quite often in this field politics comes first and science second," he told Nature Medicine. "We must take a position based on the science and the data."

 

 

Hindustan Insecticides is a/the? major producer of DDT in India.

Hindustan Insecticides Ltd is a Indian government owned operation which has been criticised, by a government environmental agency, for polluting the river it was sited on before and after it burnt down. I believe it is now back in production

http://www.hinduonnet.com/fline/fl2120/stories/20041008002803600.htm

. . .Hindustan Insecticides Ltd., Eloor (a Government of India enterprise manufacturing insecticides, where a major fire had engulfed the endosulfan plant in July) should be closed down and that the area "should be allowed to recover from the various toxic materials and chemicals used by the company and discharged by it into the environment over the decades."

 

This from the country that gave us neem one of the safest organic pesticides

 

http://www.hindustantimes.com/news/181_1759613,0008.htm

Data from the 2001/2002 findings of the All-India Co-ordinated Research Project on Pesticides (AICRP), a wing of the Indian Agricultural Research Institute, shows that 63.5 per cent of 529 vegetable samples tested had pesticide residues. Of the 199 vegetable diet samples surveyed, 26 per cent had DDT, which causes cancer, mutations and convulsions, among others.

 

The AICRP also detected pesticides such as DDT and MCH (methylcyclohexane) in milk samples from across the country in 2001.

 

Of the 468 samples tested, DDT was detected in 41 per cent samples, and MCH in 65 per cent. DDT and MCH are known to cause cancer and genetic defects.

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DDT is the totemic baddy of the green movement

http://www.spiked-online.com/Articles/000000005591.htm

DDT is the totemic baddy of the green movement. Suspicions about it caused the first green crusade, inspired by Rachel Carson's Silent Spring nearly 40 years ago. When it was used in vast quantities in agriculture, DDT probably harmed reproduction in birds of prey - but this harm subsequently proved reversible.

 

After 50 years of study there is not one replicated study that shows any harm to humans at all. And DDT is now only used for vector control, and is only sprayed inside houses. Dr Amir Attaran from Harvard University estimates that the amount of DDT used to spray a few acres of cotton in the USA in the early 1960s would spray all the homes in Guyana of those at risk of malaria - and that such indoor spraying will have 'negligible impacts on the environment'.

 

Despite the evidence, Greenpeace militants have been protesting to close down DDT's only major production facility in the world, in Cochin, India. The Indian government has given its assurance to Greenpeace that production will cease from 2005. But fortunately, India's National Anti-Malaria Programme has objected to this commitment, because it has used DDT to control vectors since it began its operations in 1953. The government may make an embarrassing but essential U-turn.

 

In South Africa the government stopped using DDT in 1996 - and since then malaria rates have risen by around 1000 percent, because mosquitoes are becoming resistant to the new generation of pesticides. The parasite that causes malaria is also becoming resistant to drug treatments - and out of sheer desperation, South Africa has returned to using DDT.

 

http://www.pan-uk.org/pestnews/actives/ddt.htm:

Human exposure

Analysis of human fat has been carried out occasionally in the UK showing that DDT can persist for many years. Analysis of 203 samples of mostly renal fat showed 99% contained detectable residues of DDT (see table 3)(24). Many of the levels found are above effect-level exposures required to elicit a carcinogenic response in test animals (see mice studies above). They are also well above the life-time safety exposure limit ADI of 0.02 mg/kg body weight.

Table 3. DDT* residues of in human fat (1995-1997) mg/kg (for UK)

No. of cases level

47 1.0 - 9.3

135 0.1 - 0.9

19 0.01 - 0.09

2 not found

* p,p'-DDT, o,p'-DDT, o,p'-TDE, and p,p'-DDE

 

Once stored in fatty tissue, DDT residues are sequestrated and stabilised unless they are mobilised either through lactation or significant weight loss, which burns fat. Organochlorines appear to transfer freely across the placenta from mother to foetus.

In one study involving humans, 17 people ate 35 mg/man daily (about 0.5 mg/kg daily) for 18 months suffering no ill-effect(25). In another study volunteers ate 0.31 to 0.61 mg/kg daily without any noticeable effects(26).

Residue values tend to be higher for older people. According to John Wargo of Yale University in the US, children under the age of 14 have roughly one-third the level of those over 45, and African-Americans experience levels roughly three times those of whites for corresponding age classes. It is unclear whether the differences for African-Americans are due to a variation in environmental exposure, or because of genetic differences(27).

DDT is excreted in human milk. A study carried out in Zimbabwe found high levels of DDE residues in breast milk commonly exceeded those required to cause hyporeflexia in infants(28).

Between 1950 and 1970 DDT was used over large areas of the Soviet Union. As a result, dangerously high residue levels were found in both food and human tissue(29).

DDT is found in the bodies of people living in the Arctic regions, where DDT has never been used. Along the west coast of Greenland, in Nunavik, Canada, and in Nikel on the Lola Peninsula of Russia, blood levels are only a factor of ten lower than the levels that are known to cause neurological effects in babies(30).

Levels of p,p-DDT in the UK have reduced significantly since the mid 1960s. This would be expected, as DDT has not been approved since 1984. Levels of the breakdown product p,p'-DDE are not coming down so quickly. Although the average figure has more than halved, the range has not changed much since the mid 1960's, and has even increased compared with the early 1970s and early 1980s figures(31).

 

Ecological effects

Environmental fate

DDT and its breakdown products have widespread persistence in the environment, and a high potential to bioaccumulate. It has a reported half-life in the environment of 2-15 years in most soils(32).

Many governmental and inter-governmental organisations regard DDT as a major hazard to the environment(33).

 

Fish

DDT is highly toxic to fish. The 96-hour LC50 (the concentration at which 50% of a test population die) ranges from 1.5 mg/litre for the largemouth bass to 56 mg/litre for guppy. Smaller fish are more susceptible than larger ones of the same species. An increase in temperature decreases the toxicity of DDT to fish(34).

 

Birds

DDT and its metabolites can lower the reproductive rate of birds by causing eggshell thinning which leads to egg breakage, causing embryo deaths. Sensitivity to DDT varies considerably according to species(35). Predatory birds are the most sensitive. In the US, the bald eagle nearly became extinct because of environmental exposure to DDT. According to research by the World Wildlife Fund and the US EPA, birds in remote locations can be affected by DDT contamination. Albatross in the Midway islands of the mid-Pacific Ocean show classic signs of exposure to organochlorine chemicals, including deformed embryos, eggshell thinning and a 3% reduction in nest productivity. Researchers found levels of DDT in adults, chicks and eggs nearly as high as levels found in bald eagles from the North American Great Lakes(36).

 

Developing countries

A recent overview of organochlorine use in Africa during the last 25 years concluded that continued use has led to serious problems for wildlife in terms of uptake into the tissues of many animals groups, particularly birds, with potential long-term adverse population effects(37).

 

Endocrine disrupters

DDT, DDD and DDE are all strongly suspected of being environmental endocrine disrupters (chemicals that affect the hormonal system). DDT can have reproductive endocrine effects (see above) and also has a major toxic effect on the adrenal glands. DDT-related deformities in birds include clubbed feet and crossed bills. There is also concern that it has the potential to disrupt the endocrine system of humans(38).

Resistance

Many insect species have developed resistance to DDT. The first cases of resistant flies were known to scientists as early as 1947, although this was not widely reported at the time(39). In the intervening years, resistance problems increased mostly because of over-use in agriculture. By 1984 a world survey showed that 233 species, mostly insects, were resistant to DDT(40). Today, with cross resistance to several insecticides, it is difficult to obtain accurate figures on the situation regarding the number of pest species resistant to DDT.

 

Global contamination

DDT is one of nine persistent organic pollutants (POPs) which bioaccumulate, and which are transported by air and water currents from warmer climates to temperate zones, where they have never been used. The process of degradation is dramatically slowed down in cooler climates. The global risk of adverse effects to human health and the environment has led the international community to mandate the UN Environment Programme (UNEP) to convene an intergovernmental negotiating committee (INC) for a POPs Convention to phase out production and use. The first INC meeting takes place in June 1998. This action endorses the recommendations of the Inter-governmental Forum on Chemical Safety (IFCS) Ad Hoc Working Group on POPs(41 ,42).

 

An yet the pro lobby says

http://reason.com/hod/rb112900.shtml

Conclusion

There is widespread global contamination of DDT. It is a hazard to the environment, both are areas where it is still used, and in many regions thousands of miles away where it is no longer, or never has been used. As a matter of urgency the use of DDT, a major POP, needs to be phased out

 

"The scientific literature does not contain even one peer-reviewed, independently replicated study linking DDT exposures to any adverse health outcome" in humans, says Amir Attaran. "No study in the scientific literature has shown DDT to be the cause of any human health problem," concludes Richard Tren and Roger Bate in When Politics Kill: Malaria and the DDT Story, a new study from the Competitive Enterprise Institute.

 

Such facts have failed to undermine environmentalist dogma. "Because Carson’s work led to the ban on DDT," Al Gore concluded in his commemorative introduction to Silent Spring, "It may be that the human species…or at least countless human lives, will be saved because of the words she wrote."

 

Sadly, it's more likely that, because a blinkered orthodoxy cannot accept the heretical notion that DDT has some beneficial purposes, countless human lives will be lost.

http://reason.com/hod/rb112900.shtml

 

 

http://www.iwmi.cgiar.org/pubs/working/WOR95.pdf

3.2.2 Cost-effectiveness of DDT

Malaria control decision makers who use or want to use DDT to combat malaria say they want to use it because it is both effective and inexpensive, when compared to alternatives. With budgetary constraints faced by the Ministries of Health, these decision makers find it necessary to use the least expensive option for vector control.

However, none of the malaria control or insecticide control specialists in Ethiopia, Uganda, Kenya or South Africa could cite a formal cost-effectiveness

study to assess whether IRS using DDT was, in truth, the most effective and inexpensive method to be used.

Several researchers have conducted cost-effectiveness analyses for DDT and its alternatives and found varying results. In KwaZulu-Natal, South Africa, IRS using pyrethroids was the most cost-effective vector control option when compared to insecticide treated bed nets (DDT was not considered in this study) (Goodman et al. 2001).

In contrast, cost comparisons in western Thailand

and the Solomon Islands indicated that ITNs were more cost-effective control measures than IRS using DDT (Kamolratanakul 2001; Kere 1992).

Kathleen Walker concluded in her global cost comparison of DDT to its alternatives that although globally the cost of DDT was lower than its alternatives (as of 2000), “a global cost comparison may not realistically reflect local costs or effective application dosages at the country level”: she goes on to say that “the most cost-effective insecticide in any given country or region must be determined on a case-by-case basis” (Walker

2000).

In light of her conclusion and the diversity of results in cost-effectiveness studies, it is surprising that certain countries have assumed that DDT is the most cost-effective alternative.

Ideally, cost-effectiveness studies should aid malaria vector control decision-making.

Unfortunately, many countries lack the capacity necessary to obtain and analyze data for such studies.

Among other countries,3 Ethiopia and South Africa are participating in a WHO/UNEP study funded by the Global Environment Facility (GEF) to “assess cost-effectiveness and sustainability of environmentally sound and locally appropriate alternatives to DDT” (UNE/WHO Project Brief).

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DDT does negatively affect the environment in some pretty substantial ways. It IS an extremely effective pesticide, so if we could figure out a way to use in a very limited and controlled manner.

It doesn't really affect humans however.

My dad told me that when he was a kid, companies would drive by in trucks spraying the DDT everywhere, even in large crowds of people --essentially drenching them in the chemical.

 

Anyway, my suggestion: develop some better pesticide for the areas that really need it.

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DDT

 

It doesn't really affect humans however.

Anyway, my suggestion: develop some better pesticide for the areas that really need it.

Some say it does affect humans others say it doesn't

Who are you to believe? (see quotes below)

 

My problem with it is that it is bio-accumulative. It has only been used in large doses since WW2; so we may not know all its long term affects yet

 

I would prefer to see something organic that breaks down naturally in the environment like Neem, or Pyrethrum or Quassia .

IF there are extra costs these should be paid for by the West whose aid to the developing world has been nose-diving for years

 

IT DOES AFFECT HUMAN HEALTH

http://www.caps.20m.com/OCFP.htm

WHAT ARE THE ASSOCIATED TOXICITIES OF THE MOST COMMONLY USED PESTICIDES?

 

1. ORGANOPHOSPHATES & CARBAMATES: Diazanon, Dursban, Basudin, Sevin

 

Both organophosphates and carbamates bind cholinesterases and block their action in the hydrolysis of the acetylcholine neurotransmitters, thus acting principally in the parasympathetic and central nervous system. These have now become the most widely used agricultural pesticides.

 

• Infants under 6 months appear to be particularly susceptible because they have incompletely developed acetylcholinesterase systems and their immature livers are unable to detoxify these compounds.1

 

• It appears that not only is this age group more susceptible to toxicity due to physiological difference but their activity and diets also put them at increased risk. Zwiener and Ginsberg12 investigated 37 children exhibiting moderate to severe organophosphate and carbamate toxicity. Although the majority were the result of accidental ingestion 17% of the patients developed signs and symptoms of moderate to severe pesticide toxicity after playing on sprayed surfaces.

 

• Visual system damage is linked to dietary exposure to some cholinesterase inhibitory compounds.1

 

• Neurotoxicity depends on the stage of brain development of those exposed. As different human brain structures have varying peak periods of growth it is felt that, like lead toxicity, prenatal and early childhood exposure is particularly toxic.1

 

• Sherman (1995) describes 4 children with an unusual pattern of birth defects including defects neurological and genitalia. Exposures had occurred in utero to Dursban an organophosphate pesticide. A review of the literature shows similar defects in test animals and other children exposed to organophosphates.13

 

IT DOESN'T AFFECT HUMAN HEALTH

http://www.21stcenturysciencetech.com/articles/Fall02/Mosquitoes.html

Fortunately, no human beings have ever been harmed by DDT

“Extensive scientific studies have not found any harm to humans, even during the massive overuse of DDT in agriculture in the 1950s and 60s.” Furthermore, the scientific reports show that there is no indication of DDT use harming people, birds, bird eggshells, or other vertebrate animals.16

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And I used to like pumpkin soup

http://www.naturalnewswire.com/2004/10/the_green_side_.html

 

The 'Green' Side of Pumpkins — Purging Pollution from Contaminated Soils

 

While parents and youngsters are busy carving jack-o-lanterns in preparation for Halloween, Canadian scientists are hard at work on another way to use the popular yellow-orange plant. New research shows that pumpkins can clean up soil contaminated with DDT and other pollutants.

 

In a greenhouse study, members of the Cucurbita pepo species — including pumpkin and zucchini — demonstrated the ability to remove DDT from soil, suggesting a potential "green" technique for cleaning up sites contaminated with DDT, PCBs and other harmful compounds.

 

The report is scheduled to appear in the Nov. 15 edition of Environmental Science & Technology, a peer-reviewed journal of the American Chemical Society, the world’s largest scientific society.

 

DDT was applied widely as an insecticide in North America until it was banned in 1972. Some developing nations still use DDT for protection against typhus and malaria, and it endures for long periods of time in the environment, posing a potential health threat to humans and animals.

 

"Persistent organic pollutants" like DDT, PCBs and dioxins are difficult to remove from soils because they are not water soluble, and the difficulty increases with the passage of time. To clean up contaminated sites, it is typically necessary to excavate the soil and place it in a landfill or burn it in a high-temperature incinerator.

 

"Phytoremediation offers a ‘green’ solution to cleaning up contaminated sites," says Ken Reimer, Ph.D., a chemist at the Royal Military College of Canada and corresponding author of the paper.

 

Phytoremediation broadly refers to the use of plants to take up contaminants from the soil. In the case of pumpkins, rather than being eaten, both the plants and their vines would be cut down after they ripen and then composted to reduce their volume before being disposed of in landfills or incinerated.

 

"Our research has shown that members of the Cucurbita pepo species, including pumpkins, are particularly effective in this regard," Reimer says.

 

Reimer and his coworkers, Alissa Lunney and Barbara Zeeb, conducted a greenhouse study of five plant species: rye grass, tall fescue, alfalfa, zucchini and pumpkin. The researchers used soil from a site in the Canadian Arctic where DDT had been sprayed to protect workers from mosquitoes.

 

"The cold temperatures meant that the contamination was virtually identical to the technical grade DDT mixture that had originally been used," Reimer says. "We could therefore examine the ability of [the plants] to ‘suck’ the DDT out of the soil that had been contaminated with DDT for several decades."

 

Pumpkins took up the largest amount of DDT, while another member of the Cucurbita pepo species — zucchini — came in second at about half the pumpkins’ accumulation. This success could be due to the large mass and volume found in members of this species, the researchers suggest.

 

Phytoremediation with pumpkins would be most useful at small sites where cleanup is less urgent, Reimer says. Ideally, the plants would grow undisturbed until they are harvested — for disposal rather than for food — at the end of the season, and the process could be repeated for several planting cycles.

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interesting. any idea if the pumpikins actually change ddt into something less harmfull? or is it basically a big DDT baloon that they throw in another spot?

Most of the chlorinated hydrocarbons arn't known for their biodegradablity.

As I read the article the pumpkins just gathered up the DDT.

DDT does break down to DDE.

Some CH's are said to have half lives of 18 years but no one has shown what they break down into.

Mostly I think they just spread out.

One or two ( toxaphene?)used to not be able to be detected at all :naughty:

I don't know if that is still the case

(CHS)are relatively safe but the objection to their use stems from the fact that they are not degraded by natural biological processes and become a permanent part of the environment.

http://www.michigan.gov/dnr/0,1607,7-153-10370_12150_12220-26633--,00.html

also same article:_

Acute toxicity can occur due to either acute exposure or as a result of the utilization of fat containing high concentrations of accumulated DDT during periods of starvation. The DDT which was stored in the fat is suddenly released into the bloodstream and results in signs of acute organochlorine poisoning.

This is what happens to seals when they give birth. The CHs interfere with the maternal response and the seals bash their babies to death.

 

Same article-

some info on birds -so much for that previous quote about birds no being affected.

Whay are there so many lies about? Who are the lies protecting? Who makes the money?

One of the major effects of organochlorine toxicity in wildlife (avian species) is the decline in eggshell thickness with a resultant decrease in reproductive success.

There is a direct correlation between high DDE (metabolite of DDT) levels in the eggs and thinning of the eggshells.

Contaminated eggs also have a greater incidence of embryonic mortality and there often is decreased survivability of hatchlings partly due to abnormal parenting behavior.

 

 

Signs of DDT toxicity in birds include ataxia, wing droop, jerkiness in gait, tremors, and convulsions. When symptoms are prolonged for a few days, acute toxic tubular nephrosis may result.

If the insecticide is eaten, an enteritis will be present and result in dehydration.

Aldrin and dieldrin produce signs of toxicity similar to those of organophosphates due to an inhibition of acetyl-cholinesterase.

Michigan Dept of Natural resources.

http://www.michigan.gov/dnr/0,1607,7-153-10370_12150_12220-26633--,00.html

 

If "abnormal parenting behaviour" had been observed on Rats in a Psyc. Laboratory (except, as is the case, in seals and birds) we would be worried. How are we less like seals and birds than rats?

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DDT may be harmful but it gets the job done. In areas where the mortality rates are higher than those created by DDT, there is net gain. On the other hand, where it creates harm beyond discomfort it should be banned. There is not just one answer.

 

Back in the 1950-60's there was wide scale spraying of DDT, before all the risks were know. The spraying would occur while children ran to watch. As far as I know, the life expectancy increased for that generation with respect to previous generations. DDT didn't caused assured mortality and lower life expectancy, although such did indeed occur at some level.

 

What one needs to keep in mind is that our ability to measure substances at lower and lower levels, often creates a misunderstanding of the data. It is the old axiom, " out of sight out of mind". For example, at one time mercury could only be measured down to PPM. If it was below detection nobody was afraid. When the tools got better, it could be measured to PPB. What couldn't be seen was now seen, making the problem appear worse, because it was now in sight and therefore in the mind. As equipment gor better still, it could be measured to PPT. Now we can't hide from mercury anywhere, making almost everybody paranoid at mercury levels that should have little impact on the vast majority. But science will attempt to correlate even the trace and using the marvel of statistics, come up with a misleading relationship that drives social policy. One has to find 1 out of 1,000,000, it market it as the rule instead of acception.

 

Let give an example of accurate but misleading statistics. If we look at the terrorists, most are Muslum. In that religion, drinking alcohol and doing recreational drugs is taboo and is treated harshly. As such, people who do not drink alcohol and/or do not do recreational drugs are far more likely to become terrorists. One could do an accurate study to get hard numbers, but the result, as stated, although true, will be very misleading. One may conclude that we need to have national beer blasts, regularly, to help lower the risk of home grown terrorists. The tea totter metality, that favors the behavior of Muslum terroorist, may also be a partial cause of home grown terrorists. It also suggests the way to deal with terrorist is to bring them to bars, get them drunk so they can vent and bar room brawl, and then form friendships with their new found drinking buddies.

 

The point I was making is that science needs to be able say this person will have an affect at a certain level of DDT, but a different person is good to a higher level of DDT. This will avoid the one-size fits all mentality created by statistical studies that be be quite misleading. This latter is called rational sicence while the former is fuzzy statistical science that allows one to draw subjective instead of objective conclusions.

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