Environmental pollution and diseases of the elderly | Umweltbundesamt

Each stage in life has its vulnerabilities. Until just recently it was assumed that children react particularly sensitive to environmental influences and that adults suffer less from environment related adverse health conditions. However, a new awareness regarding environmental influences is gaining ground, that later phases in life should be considered as well.
A reasonable explanation is the often decade-long influence of environmental factors or the exposure to environmental chemicals which can play a relevant role in the development of diseases. For many years now such risk factors have been studied and evaluated by environmental medicine and public health. For example it is beyond dispute that high levels of ozone in the air can aggravate asthma symptoms or that there is connection between high air pollution and hospital admissions due to cardiovascular diseases.
It was not until recently, however, that environmental risk factors are also thought to cause or at least influence age related diseases such as Parkinson’s or Alzheimer disease. Therefore UBA has the intension to deal with the role of environmental pollutants and the development of old-age related diseases and aims in supporting intended research in this field.
Any possible preventive measures derived from this research would be a benefit for the society because at present more than 1 million people in Germany suffer from dementia and around 250,000 from Parkinson’s disease. These illnesses pose an immense challenge for those affected, their caretakers and society in general.
The processes taking place in the course of these diseases can be explained, but up to now there are no uniform hypotheses about their actual cause. What they have in common is the brain cell damage that goes along with these diseases. Particularly problematic is their progressive cause and that treatment possibilities are very limited especially in advanced stages of the diseases. There are plausible assumptions as to why environmental pollutants could play a role in these processes. For example, they can act directly on the brain or affect other organs or hormones responsible for neurological functions. Pollutants associated with such age-related diseases include: heavy metals such as lead and mercury, aluminum, solvents such as toluene, pesticides, fine dust in ambient air and hormonal substances such as bisphenol A. In the scientific literature there are a number of review articles on this topic, we have added some important ones (list of references).
There are many difficulties in explaining the role of environmental influences and pollutants during the course of an illness. For example, little is known about the role of air pollution exposure because diagnosing physicians do simply not normally ask the patients about air quality related exposures.
In scientific epidemiological studies there are methodological problems; for example:

• past exposures to toxic pollutants that have happened long before the exposure assessment are difficult to quantify,
• exposure is often caused by mixtures of pollutants, each substance in a small dose, and
• a lot of factors like smoking or professional exposures as well as non-chemical influences, for example lifestyle, might confound research outcomes.

Current approaches to prevention of Alzheimer's disease as described in the scientific literature are based on changes in a healthier lifestyle (including physical exercise, mental activity and diet). A further important element could also be a reduction in environmental pollution. For example, a German study (women aged between 68 and 79 years) carried out by the University of Düsseldorf showed a link between cognitive test results and proximity to road traffic. A recent Danish study points out a similar correspondence for Parkinson’s disease.

References:
Chin-Chan M, Navarro-Yepes, Quintanilla-Vega: Environmental pollutants as risk factors for neurodegenerative disorders: Alzheimer and Parkinson diseases. Frontiers in Cellular Neurosciences 9, 124 (2015) 1-22.
Goldman SM: Environmental toxins and Parkinson's disease. Annual Reviews Pharmacology and Toxicology 54 (2014) 141-164.
Grossmann E: Time after time, environmental influences on the aging brain. Environmental Health Perspectives 122, 9 (2014) A238-A243.
Kieburtz K, Wunderle KB: Parkinson's disease: Evidence for environmental risk factors. Movement Disorders 28, 1 (2013) 8-13.
Ngandu T: A 2 year multidomain intervention of diet, exercise, cognitive training, and vascular risk monitoring versus control to prevent cognitive decline in at-risk elderly people (FINGER): a randomised controlled trial. Lancet 385, 9984 (2015) 2255-2263.
Ranft U, Schikowski T, Sugiri D, Krutman J, Krämer U: Long-term exposure to traffic-related matter impairs cognitive function in the elderly. Environmental Research 109 (2009) 1004-1011.
Ritz B, Lee P-C, Hansen J, Funch Lassen C, Ketzel M, Sörensen M, Raaschou-Nielsen O: Traffic-related air pollution and Parkinson's Disease in Denmark: A Case-Control study. Environmental Health Perspectives 24, 3 (2016) 351-356.