Parkinson's disease is the fastest growing neurological disorder worldwide. An increasing number of studies are also looking at environmental factors that could plausibly have contributed to the rapid increase.
Neurological diseases are now the leading cause of disability worldwide and the fastest growing neurological disease is Parkinson's disease. From 1990 to 2015, the number of people with Parkinson's doubled to over 6 million. It is estimated that the number could reach 17 million by 2040.1
While the ageing of the population plays a role, it alone cannot explain these trends to this extent. In 1855, forty years after Dr. James Parkinson first described the disease, about 22 people in England and Wales (out of a total population of 15 million at the time) died of the disease.1
"For most of human history, Parkinson's was a rare disease. However, demographics and the by-products of industrialisation have now generated a Parkinson's pandemic that requires increased action, targeted planning and new approaches," summarise the authors of a review paper in the 'Journal of Parkinson's Disease'.1
It has been suggested that a relevant proportion of the disease could possibly be prevented simply by reducing air pollution. Quantifying the influence of environmental factors is always tricky, because it is often the interaction of factors that makes the poison, but nevertheless studies of individual influences already provide many helpful indications. Another difficulty is the latency until the manifestation of the disease, which means that some connections remain unclear for a long time (as in the case of smoking and lung cancer).
At this point, one could continue with considerations such as solvents or pesticides (for which there is also exciting work on the association with various diseases). But: since these topics already enjoy more attention and awareness, we want to draw attention to two associations that are surprisingly little talked about, despite a growing and exciting body of evidence.
A very important and strong review in The Lancet addressed what is probably the fastest growing anthropogenic environmental exposure since the mid-20th century: electromagnetic radiation.
Exposure to electromagnetic fields is now being studied in more detail as a risk factor for neurodegeneration and has already been linked to the development of diseases such as Parkinson's disease and Alzheimer's disease.4
Electromagnetic fields (EMFs) damage cells through oxidative cell stress. This is confirmed again by a recent (and at the same time probably the most comprehensive) review. It was funded by the Swiss government and prepared by the University of Bern.2,3
Animal studies showed consistent evidence of oxidative stress after radiofrequency EMF exposure, also at mobile phone frequencies, especially in the brain and testes, but also in the heart, kidneys and liver. These observations were made with a variety of cell types, exposure times and doses (SAR or field strengths) that were within the ranges of legal limits and recommendations.
Alterations in the metabolism of the amyloid precursor protein (after exposure to mobile phone radiation for three times 10 minutes over two days) could also be measured. Furthermore, an altered accumulation of α-synuclein (the equilibrium shifted from the multimeric to the monomeric form) as well as the induction of cell death were documented.4
Even if the experimental setups could sometimes be more realistic or comprehensive (e.g. with regard to exposure time or dose), an alarming trend has nevertheless been emerging for some time: EMF exposure, even in the low dose range, can severely disrupt the cellular oxidative balance. The studies show that very young or old individuals can respond less efficiently to this, which of course also applies to other influences that cause oxidative stress.2,3 Further studies also showed that prenatal exposure to radiofrequency fields can almost triple the risk of miscarriage and that increasing EMF exposure further increases the risk of infertility in males (side note: the average sperm count has already halved globally due to various influences).5
Exposure to radiofrequency electromagnetic radiation in the 1 GHz frequency band, used primarily for modern wireless communications, has, in 2018, already increased by a factor of 1018 (!) from low natural levels.6 New technologies like "The Internet of Things" and 5G are about to add millions more radiofrequency transmitters around us.
To briefly turn back to "classical" pollution: The toxicity of some types of toxins unfortunately seems to be amplified by EMFs - this is especially true for nanoparticles, to which we are also increasingly exposed.7 The maximum amplification effect has also been described here just below 1 GHz.
Even beyond Parkinson's disease, it is clear that a more comprehensive picture must emerge, which includes environmental factors and their interactions with epigenetic mechanisms as well as nutrition, behaviour, stress, physical activity, lack of sleep, work habits, smoking or alcohol consumption, because especially for diseases for which there is still no curative therapy, the precautionary principle should have top priority - think of diseases such as Alzheimer's disease. Also, for Alzheimer's many such, in principle preventable, factors have been described that are associated with a significantly increased risk of disease, again including EMFs, pesticides, solvents and aluminium.8
A final example for today: Did you know that aluminium is one of the most studied environmental toxins, especially in relation to neurological diseases? In vitro and in vivo studies have demonstrated a significant influence of aluminium and other trivalent metal ions on the pathogenesis of neurodegenerative diseases.9 Several studies in humans have shown that a high intake of aluminium (e.g. from air or drinking water) and the frequent use of aluminium-containing products is associated with an increased risk of Alzheimer's disease.8 Aluminium also triggered increased aggregation of tau-proteins in vitro.9
A small study of brains from young donors reported extraordinarily high levels of aluminium in the brain, both extracellularly and intracellularly, the latter affecting neurons as well as non-neuronal cells. The presence of aluminium in inflammatory cells in the meninges, vasculature, grey matter and white matter was a remarkable observation.10
Aluminium oxyhydroxide, which is often used as an adjuvant by the pharmaceutical industry, consists of primary nanoparticles that agglomerate spontaneously. Concerns about its safety arose after its unexpectedly long biopersistence within immune cells was recognised in some individuals and linked to chronic fatigue syndrome, cognitive dysfunction, myalgia, dysautonomia and inflammatory and autoimmune processes.
Mouse experiments have documented the uptake and slow transport by monocytes from the injected muscle to the lymphoid organs and finally to the brain. Here, for once, the dose does not seem to make the poison; surprisingly, a selective low-dose neurotoxicity has been described. Here, rather, a particularly small particle size seems to be decisive for whether uptake into the monocytes and the described transport pathway take place.11
Studies on such and many other correlations could shift the balance from challenging management of chronic lifestyle diseases more towards their prevention.
"When the incidence of a disease changes from one generation to another, it suggests that the culprit is environmental rather than something biological"
- Prof. Kimmie Ng, Harvard Medical School, Boston (while speaking about cancer, but I think the saying is applicable to many fields)12
References:
1. Dorsey, E. R., Sherer, T., Okun, M. S. & Bloem, B. R. The Emerging Evidence of the Parkinson Pandemic. J Parkinsons Dis 8, S3–S8 (2018).
2. Schuermann, D. & Mevissen, M. Manmade Electromagnetic Fields and Oxidative Stress—Biological Effects and Consequences for Health. International Journal of Molecular Sciences 22, 3772 (2021).
3. Studie für die Schweizer Regierung weist nach: EMF Ursache vieler Krankheiten durch oxidativen Zellstress. https://www.diagnose-funk.org/publikationen/artikel/detail?newsid=1692. (English title: Study for the Swiss government proves: EMF cause of many diseases due to oxidative cell stress.)
4. Stefi, A. L., Margaritis, L. H., Skouroliakou, A. S. & Vassilacopoulou, D. Mobile phone electromagnetic radiation affects Amyloid Precursor Protein and α-synuclein metabolism in SH-SY5Y cells. Pathophysiology 26, 203–212 (2019).
5. EMF Exposure Linked to Miscarriage and Male Infertility. Mercola.com http://articles.mercola.com/sites/articles/archive/2020/03/31/emf-exposure-linked-to-miscarriage-male-infertility.aspx.
6. Bandara, P. & Carpenter, D. O. Planetary electromagnetic pollution: it is time to assess its impact. The Lancet Planetary Health 2, e512–e514 (2018).
7. Saliev, T. et al. Impact of electromagnetic fields on in vitro toxicity of silver and graphene nanoparticles. Electromagn Biol Med 38, 21–31 (2019).
8. Olayinka O et al. Toxic Environmental Risk Factors for Alzheimer’s Disease: A Systematic Review. Aging Medicine and Healthcare 10(1), 4–17 (2019).
9. Der Einfluss dreiwertiger Metallionen auf die Entwicklung des Morbus Parkinson im transgenen Tiermodell.
(English title: The influence of trivalent metal ions on the development of Parkinson's disease in a transgenic animal model.)
10. Mold, M., Umar, D., King, A. & Exley, C. Aluminium in brain tissue in autism. Journal of Trace Elements in Medicine and Biology 46, 76–82 (2018).
11. Crépeaux, G. et al. Non-linear dose-response of aluminium hydroxide adjuvant particles: Selective low dose neurotoxicity. Toxicology 375, 48–57 (2017).
12. Colorectal Cancer Rising among Young Adults - National Cancer Institute. https://www.cancer.gov/news-events/cancer-currents-blog/2020/colorectal-cancer-rising-younger-adults (2020).