Update Could Pollutants such as Metals Contribute to the Cause of Alzheimer's?
Recently, we received a question about whether pollutants or radon could cause ‘forgetfulness.' As a result I want to throw some light on this very complex area. We often think of symptoms that include changes in memory, memory loss and, in some cases, confusion, as some type of dementia. However there are also many other diseases and conditions where these symptoms may be present.
As yet we do not know why people get Alzheimer's and indeed whether Alzheimer's has one cause or, more likely, is multi-causal. This means scientists are looking at all types of agents, at physical changes in the brain and nervous system, at risk factors such as an individual's genetic make up, diet, age, heart disease and many other things to see if they affect how Alzheimer's disease begins and evolves.
Pollutants such as metals are also an obvious target for investigation for contributory causes for Alzheimer's. But their roles are not necessarily straight forward. In May 2011, Dorian shared information about research linking traffic pollution to brain inflammation and Alzheimer's disease. Researchers from the University of Southern California found that mice subjected to traffic pollution showed signs of inflammation that was similar to Alzheimer's disease. It is just one example where animal studies find brain damage of the type seen in people with Alzheimer's.
Mercury is also under investigation. A study from the University of Freiberg found higher mercury concentrations in brain regions and the blood of some patients with Alzheimer's disease (AD). Low levels of inorganic mercury were able to cause AD-typical nerve cell deteriorations in vitro and in animal experiments. The main human sources for mercury are fish consumption and dental amalgam (Hg vapor). In recent times there has been a lot of concern about the use of mercury used for dental fillings but the evidence is by no means conclusive.
Another example of findings by scientists, this time from Keele University in the UK, have found raised levels of magnetic iron oxides in the part of the brain affected by Alzheimer's Disease. But there is still little known about the chemical form of iron associated with these diseases, its role in neuro-degeneration (if any) and its origin.
Metals, pollutants and of course diseases where it can be demonstrated that metals cause memory loss and confusion show just how important medicine and science is to understanding human behavior and illness.
- Carbon monoxide poisoning
- lead poisoning
- thallium toxicity
- copper build up of Wilson's disease,all show symptoms of memory loss and confusion. Understanding just what the role of various metals is in Alzheimer's disease is just the first step in a complex process. Demonstrating cause and effect is not always easy and the aspect of pollutants demonstrates how difficult it is going to be finding the causes and the possible cures (there may be more than one) for this debilitating and horrible disease.