Alzheimer's disease through pesticide DDT contact

Connection between decomposition products of the insect venom and the occurrence of Alzheimer's

04/28/2014

Although the causes of Alzheimer's are still not fully understood, it is believed that a combination of genetic, environmental and lifestyle factors forms the basis of the disease. Now, US scientists have in the journal „JAMA Neurology“ published a study that concluded that residues of the pesticide DDT (dichlorodiphenyl trichloroethane) appear to play a crucial role here.

Although the use of DDT is now banned almost everywhere in the world, many people still find long-lived pesticide degradation products, Jason Richardson of the Department of Environmental and Occupational Medicine at Rutgers Robert Wood Johnson Medical School (New Jersey). Significantly increased concentrations of these degradation products (dichlorodiphenyldichloroethene, DDE) have already been demonstrated in previous studies in Alzheimer's patients. Now, the US scientists have reviewed the earlier results in a larger sample and found here also increased DDE concentrations in the blood of Alzheimer's patients. This suggests that there is a connection here, write Richardson and colleagues.

DDT breakdown product in the brain of Alzheimer's patients
For decades, DDT was the most widely used insecticide worldwide before it was realized that environmental and health damage was not sustainable. In particular, the fact that DDT is extremely poorly degradable and accumulates in the long term in the environment, but also in the human and animal organism, has led to a ban in most countries worldwide since the 1970s. Nevertheless, there are still degradation products of the insect venom in the bodies of many people. For example, Richardson and colleagues found significantly elevated DDE levels in the study of blood levels in 86 Alzheimer's patients over the age of 60 years. The comparison with 79 healthy subjects showed that the DDE concentration in Alzheimer's patients was on average 3.8 times higher. This suggests the suspicion that there is a connection here. Also tests of brain function would have shown that this decreases significantly with increasing DDE concentration.

Environmental risk factor identified for Alzheimer's
The researchers also investigated how DDT or its degradation products can affect the development of Alzheimer's disease. In experiments with cell cultures, they found that DDT and DDE promote the production of proteins that form a precursor of the protein beta-amyloid, which in turn is increasingly found as a deposit in the brain of Alzheimer's patients and with the onset of neurodegenerative disease in Connection is made. Although the size of the sample is still too small to establish a clear correlation, the US researchers assume that an environmental risk factor for Alzheimer's was identified here. It is also conceivable that the insect venom also plays a role in the development of other neurodegenerative diseases, such as Parkinson's disease.

Long-term consequences of the use of pesticides hardly predictable
Finally, the study again confirms the danger of the insecticide DDT and makes it clear that the long-term consequences of introducing such toxins into the environment are hardly predictable. While DDT was widely hailed by many farmers as a great way to increase yields, today most are sobered by its negative impact on humans and animals. But new funds are moving forward and again and again a resourceful company discovers alleged miracle weapons against insects and weeds. Here are the discussions on genetically modified potatoes and soybean plants are reminiscent, which were specially developed resistant to special pesticides and herbicides. This should continue to allow the use of appropriate toxins without damaging the crops. The long-term consequences are again hardly predictable. (Fp)