Thursday, April 20, 2006


The April 14th issue of Science contains an article titled "Environmental Science Adrift in the Blogosphere" by Alison Ashlin and Richard J. Ladle. The article summary states:
Weblogs are a growing global phenomenon with important consequences for science policy and communication. A survey of blogs on environmental topics shows that they vary greatly in accuracy, which indicates a need for participation by informed scientists.
Apparently – I'm not a Science subscriber and don't have access to the article – one of the "excellent, informative sites" recommended is Science Blogs. Well, either Ashlin and Ladle haven't read Deltoid or they're endorsing Tim Lambert's continuing dissemination of misinformation.

Here's Lambert's description of his blogging mission (my bold):
I'm a computer scientist in the School of Computer Science and Engineering at the University of New South Wales in Sydney, Australia. I don't blog about computer science very much but rather about areas of science with political implications such as global warming, the relationship between guns and crime and the use of DDT against malaria. Usually I'm inspired by reading an article and noticing something that doesn't seem to be correct. I then do a little bit of research and before you know it I have a blog post explaining what is wrong and why it is wrong.
So, Deltoid isn't really a science blog, it's a political blog. That's just as well because Lambert gets plenty wrong, especially when it comes to DDT and the fight against malaria. Actually, Lambert doesn't so much get it wrong as he intentionally misinforms. A close look at his DDT-malaria posts makes this obvious.

Lambert's most recent reference to DDT is in a post critical of Greenpeace co-founder Patrick Moore for signing "a pro-DDT petition advocating policies that would cripple the United States' fight against malaria". The embedded link – Lambert continues to bounce my links to his old blog: copy and paste – leads to an earlier Lambert post titled "Petition to Kill African Children Now!" in which he observes:
The latest stunt from Africa Fighting Malaria is a petition advocating policies that would cripple the United States efforts against malaria... The goal should be to reduce malaria and you should let the experts figure out the best way to do this. It should not be to spray DDT.
The overall goal of the petition is efficient deployment of resources, not mindless spraying of DDT:
Specifically direct such funds to the actual purchase and deployment of: (1) DDT, or any other proven, more cost-effective insecticide/repellant, for Indoor Residual Spraying (IRS) in any given malarial locality; and (2) of ACTs, or other equally effective and durable drugs, for treatment of malaria patients and reduction in transmission rates.
Lambert never bothers to explain how the petition would kill African children. In view of the findings of a 2005 GAO investigation into U.S. anti-malaria efforts the petition's emphasis is not unreasonable:
Objective 2: Key Challenges to Implementation

Insufficient Financial Resources

Lack of funding for program implementation and donor support activities, including

•Updating of national prevention and treatment policies

•Establishment of monitoring, evaluation, and surveillance systems

•Capital investments—such as the purchase of equipment for IRS programs— needed to support effective policy implementation Examples of reported consequences

•Delays in implementation of updated prevention and treatment policies

• Limited capacity to expand a newly integrated policy involving the coupling of ITN use with IPT

Inability of programs to purchase a sustainable supply of insecticides, spray equipment, and vehicles for mobilization of spray teams needed to effectively implement IRS programs

• Limited use of available research and monitoring and evaluation data to make program implementation more effective
The best I can work out, not only is USAID unsupportive of spraying programs, it has so far provided $0 for the purchase of DDT. Lambert and USAID are both a bit tricky when discussing USAID and DDT, noting correctly that USAID does not ban the indoor spraying of DDT. Tricky wording aside, it's obvious USAID is not supportive of DDT use. (Copy and paste’t-against-using-ddt-in-worldwide-malaria-battle/ to access the USAID post.)

Lambert also indicates that the World Health Organization supports DDT use by citing this from a WHO DDT FAQ brochure:
WHO recommends indoor residual spraying of DDT for malaria vector control.
On the surface this appears to be a recommendation of DDT use when, in fact, it's merely recommending how DDT should be used if it's going to be used:
How is DDT used for malaria vector control?

WHO recommends indoor residual spraying of DDT for malaria vector control.
Did Lambert intentionally misinform his readers by citing that quote out of context or is he simply ignorant? I'm inclined to believe the former; either way it's hardly the quality one should expect from a science based blogger who's right into fact-checking. Anyway, the WHO brochure is hardly a glowing endorsement of DDT:
Why is DDT use for malaria vector control so controversial?

DDT is a persistent organic compound. This means that the compound can stay in the environment long after its initial application as an insecticide (up to 12 years). During this time, DDT and its breakdown products may enter the food chain and accumulate in fatty tissues (bioaccumulation). Harmful effects in the wildlife population have been linked to DDT, including the thinning of eggshells in birds exposed to the compound. There are also fears that DDT may have a long-term impact on human health. Although there is currently no direct link between DDT and any negative human health effect, there is growing evidence that it may disrupt reproductive and endocrine function. Opponents of DDT use for vector control argue that its use should be curtailed on these grounds.

Advocates of the continuing use of DDT as an insecticide for disease vector control base their argument on various factors: the unacceptably high levels of mortality and morbidity caused by malaria, the proven effectiveness of DDT in significantly reducing malaria transmission, the relatively low cost of DDT interventions, and the lack of any sustainable alternative in many endemic countries. They argue that the negative environmental and other effects associated with DDT use in the past reflect the massive uptake and bioaccumulation arising from the high amounts used as general agricultural pesticide. The amount of DDT used for disease vector control is negligible compared with that used in agriculture. The advocates also argue that when strictly used indoors, as recommended by WHO, DDT poses very little if any environmental threat.
The main reason DDT is so controversial is because discussions like that above continue to emphasize the supposed hazards associated with DDT use. Tim Lambert's intentionally misleading posts just add to the confusion.

Update: Here's another example of WHO's negative view of DDT, this from the WHO Expert Committee on Malaria 20th Report:
3.2.1Indoor residual spraying with insecticides

In many programmes, mainly in the Americas and some countries in Asia, indoor residual spraying continues to be the main vector control measure implemented. There is, however, a tendency to reduce reliance on spraying, and there is also a marked decrease in the use of conventional residual insecticides, such as DDT, which have been replaced by new-generation insecticides, such as the pyrethroids, at considerable financial cost to the programmes. Improvement in local knowledge of malaria epidemiology (especially disease transmission), with refinement of surveillance mechanisms and proper use of collected data, could lead to the implementation of more selective vector control and further reduce reliance on indoor residual spraying.

8.1.1Indoor residual spraying

Non-selective coverage, as used for DDT and other insecticides in the past, is no longer a recommended strategy. Reduction of widespread coverage is still needed in the Americas, Asia and in some areas of Africa (where malaria transmission is focal and unstable, and in epidemic-prone areas). Given the financial and human resources involved, combined with the potential for vector resistance and environmental concerns, indoor residual spraying should be used only in well defined, high or special risk situations. DDT is being phased out because of its previous widespread use in the environment, and the resulting political and economic pressure.
The pressure was on back when this report was written, around the time the Stockholm Convention on Persistent Organophosphate Pollutants (POPs) Treaty was being negotiated, to eliminate DDT from the anti-malaria arsenal. Tim Lambert often claims DDT has fallen into disfavour mostly because mosquitoes became resistant to it; the WHO report indicates that there were political and economic pressures but does not specifically mention DDT resistance as a factor.

To be continued...


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