The truth about DDT…?
I’ve heard it claimed many times that “environmentalists” killed more people than died during the holocaust because they pushed for a ban on DDT. These supposed millions of deaths are from malaria, which DDT would have helped eradicate.
I always respond by pointing out that treaties have banned the use of DDT in agriculture, but its use in vector control has NEVER been banned. Today, about 4-5,000 tonnes of DDT are used each year for the purpose.
They’ll then respond by saying something like, “DDT perhaps can be used for vector control, but it’s not as widely used because the “environmentalists” convinced the US government not to trade with countries that used it for this purpose.
DDT is less effective in tropical regions due to the continuous life cycle of mosquitoes.
Because of this, civil unrest, and poor infrastructure, eradication of Malaria was never attempted in sub-Saharan, which now constitute the bulk of malarial deaths.
Today, the fight against Malaria has shifted from eradication to controlling and treating the disease. This is done through indoor spraying, widow screens, bed netting, and drug treatment.
So who’s right? Are “environmentalists” responsible for millions of unnecessary deaths? Or is blaming “environmentalists” for the failure of malaria eradication unfounded and irresponsible? Are there truths in both sides of the argument?
July 3rd, 2010 at 6:36 am
DDT is a persistent organic pollutant that is extremely hydrophobic and strongly absorbed by soils. Depending on conditions, its soil half life can range from 22 days to 30 years.
DDT is toxic to a wide range of animals in addition to insects. It is highly toxic to aquatic life, including crayfish, daphnids, sea shrimp and many species of fish. It is less toxic to mammals but cats are very susceptible, and in several instances cat populations were significantly depleted in malaria control operations that used DDT, often leading to explosive growth in rodent populations.
Potential mechanisms of DDT on humans are genotoxicity and endocrine disruption. DDT may have direct genotoxicity, but may also induce enzymes that produce other genotoxic intermediates and DNA adducts.
There is epidemiological evidence (i.e. studies in humans) that DDT causes cancer of the: Liver, Pancreas, Breast.
Malaria remains a major public health challenge in many parts of the world. The World Health Organization (WHO) estimates that there are 250 million cases every year, resulting in almost 1 million deaths. Spraying DDT is one of many public health interventions currently used to fight the disease. Its use in this context has been called everything from a “miracle weapon to the mosquitoes,” to “toxic colonialism”
The WHO’s anti-malaria campaign of the 1950s and 1960s relied heavily on DDT and initially the results were promising, though short lived. Experts tie the resurgence of malaria to numerous factors, including poor leadership, management, and funding of malaria control programs; poverty; civil unrest; and increased irrigation.
The evolution of resistance of the malaria parasite to the drugs traditionally used to treat the disease (e.g. chloroquine) and evolution of resistance of mosquitoes to insecticides have greatly exacerbated the situation.
Resistance of mosquitoes to DDT was largely fueled by its often unrestricted use in agriculture. This, coupled with the awareness that DDT may be harmful both to humans and the environment led many governments to restrict or curtail the use of DDT in vector control.
Once the mainstay of anti-malaria campaigns, as of 2006 only 13 countries were still using DDT, including India and some southern African states, though the number is expected to rise.
South Africa is one country that continues to use DDT under WHO guidelines. In 1996, the country switched to alternative insecticides and malaria incidence increased dramatically. Returning to DDT and introducing new drugs brought malaria back under control. According to DDT advocate Donald Roberts, malaria cases increased in South America after countries in that continent stopped using DDT. Research data shows a significantly strong negative relationship between DDT residual house sprayings and malaria rates. In a research from 1993 to 1995, Ecuador increased its use of DDT and resulted in a 61% reduction in malaria rates, while each of the other countries that gradually decreased its DDT use had large increase in malaria rates.
Critics claim that restrictions on the use of DDT in vector control have resulted in substantial numbers of unnecessary deaths due to malaria. Estimates for the number of these deaths range from hundreds of thousands, according to Nicholas Kristof, to much higher figures. Robert Gwadz of the National Institutes of Health said in 2007 that “The ban on DDT may have killed 20 million children.”
You decide…
My brother and I were BOTH exposed to miniscule amounts of DDT as babies; we found later we had bone development defects, and other minor internal disorders. Thankfully we have been spared other complaints.
Report this comment