From July 26, 2006
DDT Use
in South Africa Results in Elevated Human Poisoning
(Beyond Pesticides, July 26, 2006) According
to the Independent
Online, a study, entitled Contamination of the water environment
in malaria endemic areas of KwaZulu-Natal, South Africa, by
agricultural insecticides, has found that mothers tested in South
Africa’s rural areas have pesticides, including DDT, in their
breast milk. Some of the women have 77 times the international limit
for DDT residue in humans, while in some of their babies it is 12 times
the World Health Organization’s “acceptable”
limit. The study is not yet publicly available in the U.S., but
can be accessed by registering here.
In the study, pesticides were found in the breast milk of 152 women at clinics in the towns of Jozini, Mkuze and Kwaliweni in northern KwaZulu-Natal, near Durban, South Africa. DDT is used in two of the towns to control mosquitoes that transmit malaria. Between 1995 and 2000, pyrethroids were used, then DDT usage was resumed. The pyrethroids found in the women’s breast milk are used as agricultural pesticides in the regions where they live. Mothers from Jozini had life long exposures to DDT from malaria control, and also had the highest residue rates. Scientists said the source of DDT in the town of Kwaliweni should be investigated to determine whether water or fish were the source of contamination, because mothers in that town did not report living in DDT treated dwellings.
First time moms had the highest level of DDT residues, meaning first-borns got the highest amount of the pesticide in breast milk. Scientists say that the levels of DDT found in babies warrant strong concern.
The study is one of the first in South Africa documenting high body burdens of DDT, which is associated with human developmental problems. It comes on the heels of a new U.C. Berkeley study, Association of in Utero Organophosphate Pesticide Exposure and Fetal Growth and Length of Gestation in an Agricultural Population, which shows that DDT in mothers is linked to delays in physical and mental development of their children.
Though DDT is banned in most countries, particularly industrialized ones, because of its harmful effects on the environment, it is still manufactured and sold by India and China to other lesser developed countries. DDT has also become increasingly associated with childhood developmental problems.
Debate has raged on the African continent in recent weeks as countries including Uganda and Tanzania have decided to lift voluntary bans on the pesticide in efforts to fight the spread of malaria. South Africa has also successfully lobbied neighboring African countries to lift their bans on DDT. At issue are concerns regarding the immediate, acute economic and societal costs associated with losing significant portions of the population to the deadly malaria parasite on the one hand, balanced against the potential long-term harm to people and the environment that are associated with DDT usage on the other. Additional concerns stem from the methods used to apply DDT, including “limited” applications to the interior walls of schools and homes. Proponents of such applications argue that they are better at killing the anophelese mosquito, which carries the malaria parasite, than chemically treated mosquito nets, which have been used with some degree of success up to now. Opponents of limited application argue that DDT does not work unless it is used on a large scale, including ambient spraying, which eliminates more mosquitoes, but also has an extremely deleterious impact on wildlife, the environment, and humans.
DDT, one of the world’s “dirty dozen” organic pollutants banned by the Stockholm Convention on Persistent Organic Pollutants, stays in the environment for years after use, enters the food chain, and gets stored in the fatty tissue of birds, animals and humans.
Barbara Sereda, of the Agricultural Research Council in Pretoria, South Africa, and one of the scientists who conducted the study, said that DDT was present in water and soil and had been taken up by crops.
“The results are quite scary,” Ms. Sereda said.