What finally clued them in?

-- Elliot Temple
curicuri.us
Dialogs

I'm reposting this because it's been a day or two since I tried to post it before. Apologies if this is a multiple post.

This whole DDT thing is a bunch of crap. For one thing, the WHO never banned it. The US did, after we eradicated malaria (although screens and indoor climate controls had a big part to play there too). The WHO has always advocated limited indoor use of DDT to combat the spread of malaria. The problem is, people don't take kindly to government workers coming into their homes to spray crap on their walls that stains them brown.

DDT is not a magic bullet to solve the problem of malaria in the third world. The roots of the problem are corruption, poverty, and incompetence (many times caused by centuries of European colonialism). DDT has only limited effectiveness - mosquitos quickly become resistant to it if it is sprayed in large quantities. Bed nets and anti malaria drugs would be a better option. I guess DDT could be used as part of a rotating cycle of pesticide, but there has never been anything to stop governments from doing that anyway.

Will wrote:

The WHO has always advocated limited indoor use of DDT to combat the spread of malaria.

Indeed. But didn't it cease advocating its widespread use 30 years ago? Didn't it actively promote indoor residual spraying for malaria control until the early 1980s, and did it not then focus instead on other measures because of (among other reasons) health and environmental fears about DDT? Which it now considers mistaken?

Tim Lambert who blogs at Deltoid has good information about the 'DDT' controversy:

http://scienceblogs.com/deltoid/ddt

Check out this blog post, which is quite enlightening concerning the present situation.

Two quotes:

"The fact is that until 1994, DDT was the WHO's insecticide of choice for malaria vector control."

"Nor did WHO stop promoting DDT....Alan Schapira rebutted such claims in November 2004: WHO has never given up in its efforts to ensure access to DDT where it is needed....And the WHO's 2004 statement on ITNs (nets) vs IRS (spraying) clearly supports IRS in regions of unstable transmission...."

It's a good post, read it.

Also check this one out, about the new policy.

As for environmental stuff, this is from the Telegraph article you linked to:

"So far, the clearest adverse impact of the pesticide has been a steep decline in the number of bird species in areas where it has been used." Birds are vital to the natural world. They spread plants by eating the seeds and control pests. It's no accident that Rachel Carson's book Silent Spring concentrated on birds - when they go, the natural world will go badly out of whack.

Thanks for the links, Will.

In regard to the WHO's new DDT policy, the first one seems to assert the following:

- The WHO's dramatic press release announcing a change in policy is misleading, because in fact their new policy on DDT is virtually the same as the old one.

And the second one:

- The WHO's new policy on DDT is unsound, because it was formulated by Westerners who do not understand Africa.

This is a little confusing. In your opinion, has there been a change in WHO policy on DDT or not?

I think what has happened is that the WHO always said that IRS (indoor spraying) should be used in certain areas: namely, areas where malaria levels fluctuated. One reason for this is because IRS lasts for a long time and also has a deterrent effect... it's a cheap way to keep insects from resting on your indoor surfaces for a couple years. In areas where there is a lot of Malaria, high levels all the time, they recommended other methods of control.

Now they recommend IRS for all areas, which is where the critique in the second post comes in.

Where the WHO press release (and subsequent news articles) were misleading is in the quote: "in the 1980s the World Health Organization joined other NGOs and government organisations in ceasing to promote ‘indoor residual spraying’ with the insecticide DDT as a method of combating the spread of mosquito-borne diseases, especially malaria."

They never stopped recommending it, they have just started to push it more aggressively.

That may seem like nitpicking, but it is highly annoying to environmentalists like myself, because it comes in the context of a long campaign to discredit environmental groups who don't like DDT. Once again, I recommend that anyone who's interested head over to Deltoid where Tim has been keeping up with this for a long time.

They never stopped recommending it, they have just started to push it more aggressively.

You seem to be saying: Prior to the 1980s the WHO had a certain policy about indoor residual spraying with DDT, namely to promote it in some situations and not others. Contrary to the WHO's recent press release, there was little or no change in that policy in the 1980s, but the press release is correct in saying that now there has been a change: they are pushing indoor residual spraying with DDT more aggressively. And this new policy is unsound.

Is that correct?

Yep, that's what I'm saying. Basically, anyway. From the 2005 WHO FAQ on DDT (caution, pdf):

"WHO recommends indoor residual spraying of DDT for malaria vector control."

I don't know about specific dates... but I think you restated the gist of my argument correctly. The WHO has never not recommended IRS.

Thank you; that's clear now.

And is it your position that the major environmentalist organisations such as the Worldwide Fund for Nature fought vehemently for an almost complete ban on DDT, but have now changed their policies too?

Not sure what all the major enviro groups wanted. I'm sure there were different positions. I'll look into it and get back to you.

From an editorial in the NYT by Nick Kristoff, Jan 2005:

I called the World Wildlife Fund, thinking I would get a fight. But Richard Liroff, its expert on toxins, said he could accept the use of DDT when necessary in anti-malaria programs.

"South Africa was right to use DDT," he said. "If the alternatives to DDT aren't working, as they weren't in South Africa, geez, you've got to use it. In South Africa it prevented tens of thousands of malaria cases and saved lots of lives."

At Greenpeace, Rick Hind noted reasons to be wary of DDT, but added: "If there's nothing else and it's going to save lives, we're all for it. Nobody's dogmatic about it."

To see what Rachel Carson actually said about DDT in Silent Spring, go here. Basically she's pointing out the problem of resistance - the more you spray DDT or any chemical pesticide, the more the insects develop a resistance and the less effective it is. With that knowledge, and the knowledge of what it does to the natural world and maybe to humans, it would be foolish to use DDT too much. She says:

"No responsible person contends that insect-borne disease should be ignored. The question that has now urgently presented itself is whether it is either wise or responsible to attack the problem by methods that are rapidly making it worse."

You might also look here for more information about what the World Wildlife Fund recommended in the 1990's.

I'm sure there were differing opinions. Environmental groups have a spectrum of different operational frameworks. But I don't think any major enviro group would advocate a ban on any technology that could save millions of lives. They might caution about the need for more research and caution in using the technology, and they might present alternatives that would actually work better.

"I don't think any major enviro group would advocate a ban on any technology that could save millions of lives."

Aren't you assuming your conclusion?

-- Elliot Temple
curicuri.us
Dialogs

Those last two sentences are my opinion. Please take them separately from the evidence presented in the first part of the comment.

From the WWF homepage:

Quote:

"Because of the availability of safer and effective alternatives for fighting malaria, WWF is calling for a global phaseout and eventual ban on DDT production and use."

"The first report, "Resolving the DDT Dilemma," released in June 1998, notes that DDT is linked to effects in animals or humans such as reduced lactation and reproductive problems. ...
"Resolving the DDT Dilemma" offers a framework to guide malaria control programs toward reduced reliance on all pesticides, and a 'tool kit' of alternative techniques, along with several recommendations including:

* DDT should be phased out of use and ultimately banned;
* Targeted programs emphasizing reduced reliance on pesticides and better environmental protection should be developed by WHO, World Bank, UNEP, and other multilateral and bilateral assistance agencies;
* Adequate financial and technical resources must be provided to undertake integrated vector management programs;
* Research is needed on the hazards from chronic exposure to synthetic pyrethroids being used as alternatives to DDT for indoor spraying and to impregnate bednets.

"The third report released by WWF, "Disease Vector Management for Public Health and Conservation" demonstrates that a variety of innovative mechanisms can control malaria and other diseases just as effectively as DDT. These alternatives are less harmful to the environment and human health. Detailed case studies in six areas? Africa (Botswana, Tanzania, and Western Africa), India, the Philippines, and Mexico? focus on a variety of alternative techniques.

"WWF initially [in 1999] called for a global phaseout and eventual ban on DDT production and use by the year 2007, together with financial and technical assistance to the developing world....However, it also raised fears that DDT would be phased out without sufficient guarantees of protection of public health from malaria. To allay these fears, WWF has set aside discussion of the 2007 deadline, while retaining its commitment to eliminating DDT. Both the UNEP and WHO recognize that such elimination can be a "win-win" situation for public health and environmental protection."

Tim Lambert has an older blog with a bunch more posts about DDT. From what I've been reading tonight, it looks like the main cause of the resurgence of Malaria in the 1970s was growing resistance to DDT, combined with governments trying to save money/corruption/incompetence.

http://timlambert.org/category/science/ddt/