Introduction
The insecticide DDT (dichlorodiphenyltrichloroethane) has been very successfully used for many years in the prevention and control programmes of malaria all around the world. However, it is one of the drugs that has been facing an immense level of controversy since its discovery back in the year 1874 (Casman and Hadi 17). It has been previously banned for human use, then reaccepted for continued use and still its survival is not guaranteed. Generally, DDT is an organochlorine insecticide that has been used as a pesticide for pests and insect control in the United States until it was banned in 1972 by the US Environmental protection Agency (EPA). Initially, it was being used by the military during World War II to control body lice, malaria, typhus among other insects and pests before it got adopted by farmers to spray on a variety of their crops and for home use. However, its existence has always been threatened by numerous claims that DDT leads to an array of adverse health effects to animals and human beings.
Hypothesis
DDT should continue being used as one of the best resort in combating malaria in US, Asia, Africa and other parts of the world that have been facing this problem. However, this use should be only limited to extreme situations where other control methods are not applicable.
Observation and Background Information
Malaria, a life threatening mosquito-borne disease, currently possess a risk to more than 3.4billion people, this is approximately half of the world’s population (Casman 245). Mostly, malaria poses a greater risk in sub-Saharan Africa, Asia, Latin America and also lesser cases in Europe and Middle East. In 2012, malaria was found to be in existence in 107 countries with an estimated 217 Million cases and more than 0.8 million deaths recorded; these deaths largely comprising children living in Africa. In addition, malaria places a very heavy burden to a country’s economy due to increased disease rates and expenditure in medicinal services, it has been estimated that as much as 1.4% of the GDP reduces in this countries due to the presence of malaria (Casman 300). Therefore, in light of these statistics, it is evident that rapid control measures are required so as to be able to save these malaria-prone countries from the scourge of this depilating disease. The available remedy for controlling malaria in these countries is through the use of indoor residual spraying (IRS) where insecticides are sprayed in home’s indoor walls and also the use of long lasting insecticidal nets.
The plasmodium falciparum, which is the protozoan parasite that is transmitted by an anopheles mosquito is the most deadly type of plasmodium Genus that leads to the most dangerous form of malaria (Cheremisinoff and Paul 142). In fact 75% of the deaths that are recorded in Sub-Saharan Africa, P. falciparum is usually the main cause of these cases. The malarial causing agent, the plasmodium, is known to thrive in in distinct ecological environment depending on its life cycles. The immature and adult stages of the anopheles mosquitoes are passed in different environments. The immature stage which is composed of the egg, larvae and pupae stages largely requires an aquatic environment while the adult mosquito thrives better in aerial and terrestrial environments. In this case, the anopheles mosquito is the vector that carries the plasmodium falciparum which is the pathogen and transfers it to human beings who becomes the ultimate hosts. The anopheles mosquitos normally lays its eggs in the water surface, and due to the fact that the eggs possess lateral air floats to keep the afloat, after which they later undergo all their remaining phases of their cycle. Therefore, this explains why spraying stagnant water and clearing the breeding bushes near residential places is also a very effective approach to controlling the spread of malaria.
In regard to DDT’s chemical properties, it is an insecticide with chemical formulae C14H9Cl5 therefore, for each DDT molecule, there exists 14 carbons, 9 hydrogen and 5 chlorine atoms. In its pure form, DDT is observed to being a white crystalline powder, almost similar to table salt, with little odour. One of its chemical characteristics that makes it a centre of controversy is because it is does not break down easily both in the environment and in organisms. It is insoluble in water but soluble in fats and lipids, therefore, once ingested by human or animals, it tends to stay inside the body as it mixes with the residual fats in the body. Once accumulation of DDT occurs in the body, a problem associated with DDT known as biomagnification occurs. This is biomagnification increases in concentration potentiality as an organism moves up the food chain. Due to this factor, DDT is largely associated causing different diseases such as carcinogenic effects e.g. pancreatic cancer, breast cancer, and leukaemia, and also female reproductive problems among other hormonal malfunctions.
- Pros of DDT
One of the reason why DDT is still a preferred insecticide in many malaria- infested countries is because it is a very effective pesticide which is relatively inexpensive and would last longer while maintaining its efficiency. In fact, it DDT won the 1948 Nobel Peace prize for being a highly efficient insecticide. Additionally, if used correctly, it is an effective pesticide which greatly assists farmers in fighting various pest infestations.
- Cons of DDT
DDT is largely held accountable for various possible long-term effects on the health of human being. Additionally, DDT can wash into and greatly pollute waterways. It is can also become concentrated in the food chain, it is for this reason that there are numerous claims that DDT led to the decline of birds of prey such as the bald eagles since it causes thinning of eggs, ultimately killing the embryos.
Relevant Information and Data
Although Mexico, some parts of Asia and other parts of Central America have managed to combat malaria without the use of DDT, a research carried by Cheremisinoff and Paul in the small village of Malahlapanga in South Africa showed that DDT was the only effective method to use in this locality. According to this research that was carried out 2010, These researchers reported that, in this village, malaria could breed even in running water thus making it extremely hard for other techniques of controlling malaria to effectively solve this problem. The area covered is vast and filled with small bushes which are also considered to be effective breading places for mosquitoes, and the infrastructure is also poor to allow for environmental management on a sustainable basis (Cheremisinoff and Paul 122). Therefore, the mosquito menace that had previously been eliminated through the use of DDT before its ban, is now resistant to the pyrethroid insecticides that eventually replaced DDT. Due to this, the death toll in South Africa rose from 4,217 in the year 1995 to 66, 622 in the year 2000. The South African government had no option but to fall back to the use of DDT and still uses it to date especially in the areas where the efforts in the use of other malaria control methods such as controlling stagnant ponds has proven futile.
The Ugandan Ministry of health earlier the year 2005 announced that it was preparing to reintroduce the use of DDT into their IRS programmes, the members of that parliament asked the government to secure the necessary funds to invest in the procurement of DDT (Resnik 155). In this East African region, malaria control programmes have at their disposal a wide range of interventions, however, the responsible authorities claims that no one intervention is supposed to exclude the other intervention approaches. They argue that, DDT is the only insecticide that has proven to be the most effective in this area and therefore the malaria control program of Uganda largely recommends for its use. In addition, a special commission in Uganda that had been mandated to present a report to the parliament on the possible effects of DDT showed that the inadvertent health effects of this insecticide includes: temporary nervous problems, poisoning hazard due to accidental ingestion by children and also possible carcinogenic effects when directly inhaled. It however stated that, if handled in the appropriate manner, DDT’s harmful effects would be greatly reduced. They went further to recommend it to the parliament so that the government can proceed with its procurement.
After reviewing numerous academic studies on DDT, Roll Back Malaria partnership, which is a global framework that aims at coordinating action against malaria, embarked on a study in 2007 to establish the best strategy to achieving near zero malaria deaths by the year 2015 (Resnik 255). With both the regional and global perspective, they conducted their analysis in two distinct phases: Firstly, they used the Global Malaria Atlas that clearly shows the distribution of global population data on the total count of people likely to be exposed to DDT. Secondly, they used the risk ratios or estimates of elevated risks from the available literature so as to be able to estimate the inadvertent diseases caused by exposure to DDT. According to this research, it was found out that globally, around 1.25 billion people live in places where malaria is prevalent. They further recorded that annually, losses from this disease exceeds $69billion. The findings showed that, the use of DDT can significantly reduce these losses to more than half, but it can also add to the loss through the cost incurred due to various health complications derived from the use of DDT. Nonetheless, these researchers suggests that a total of $5 billion can be saved if DDT was to be used in accordance to its usage guidelines and also when only used in the areas that are facing the highest malaria endemicity.
One of the most commonly used alternative to DDT is the use of treated mosquito nets in homes where malaria is prevalent. One of the advantage is that mosquito nets provide an effective barrier that prevents the blood sucking mosquitoes from biting and infecting people. However, although the nets do not have numerous disadvantages, the nets are expensive to some people and also are hard to repair when torn.
In conclusion, even if the use of DDT has been reported to have little adverse effects on human, it should not be used in colossal quantities so as not to have a great effects to biodiversity. From this paper, it is evident that DDT has numerous advantages and disadvantages in equal measures, therefore, a lot of caution should be adopted when handling DDT. It should only be used in extreme cases, where other method of controlling malaria have failed. Countries in Africa, Asia, Latin America and other countries that are prone to malaria should try and raise the living standards of their citizens so that they can be able to afford other methods of controlling malaria such as buying nets and repellents.
Works Cited
Casman, Elizabeth A., and Hadi Dowlatabadi, eds. The contextual determinants of malaria.
Resources for the Future, 2012.
Cheremisinoff, Nicholas P., and Paul Rosenfeld. Handbook of Pollution Prevention and
Cleaner Production Vol. 3: Best Practices in the Agrochemical Industry: Best Practices in the Agrochemical Industry. Vol. 3. Access Online via Elsevier, 2011.
Resnik, David B. Environmental Health Ethics. Cambridge: Cambridge University Press,
2012. Print.
Teklehaimanot, Awash. UN Millennium Development Library: Coming to Grips with
Malaria in the New Millennium. Earthscan, 2011.
