Research from the US has suggested that people with Alzheimer’s disease may be more likely to have higher levels of a chemical by-product of a specific pesticide in their blood. The paper is published on Monday 27 January in the journal JAMA Neurology.
Scientists led by a team at Rutgers University, in New Jersey, investigated the potential links between the pesticide DDT and Alzheimer’s disease. DDT has been banned in many countries, including the UK, for over 30 years due to concerns over its impact on wildlife – although it has been approved for indoor spraying as a means of fighting malaria in areas where the disease is widespread.
The team recruited 86 people with Alzheimer’s and 79 older people who did not have the disease, and measured the participants’ blood for levels of DDE – a compound that remains after DDT breaks down. Their results showed that people with Alzheimer’s were more likely to have higher DDE levels in their blood than people without the disease.
The researchers also tested the effects of DDT and DDE on brain cells in the laboratory. They discovered that adding either of these compounds led to an increase in the amyloid precursor protein – a protein that is needed for the production of amyloid, which accumulates in the brain during Alzheimer’s.
Dr Simon Ridley, Head of Research at Alzheimer’s Research UK, the UK’s leading dementia research charity, said:
“It’s important to note that this research relates to DDT, a pesticide that has not been used in the UK since the 1980s. While this small study suggests a possible connection between DDT exposure and Alzheimer’s, we don’t know whether other factors may account for these results. We can’t conclude from these findings that pesticide exposure causes Alzheimer’s, and much more research would be needed to confirm whether this particular pesticide may contribute to the disease.
“Research to understand the possible environmental risk factors for Alzheimer’s can help us make informed decisions to reduce these risks. Investment in research is crucial if we are to improve our understanding of the different factors that contribute to our risk of the disease. In the meantime, we do know that a healthy lifestyle can help reduce the risk of Alzheimer’s, which is why it’s important to eat a healthy, balanced diet, exercise regularly, not smoke, and keep blood pressure and weight in check.”