THE EFFECTS OF POLLUTION ON HUMAN HEALTH

Professor of Environmental Sciences at the University of Lancaster, Barbara Maher, closed our "Let's face climate change" cycle with a conference  on "The effects of human pollution". The conference took place at the Antoni Tàpies Foundation on Thursday, November 7. It was the last of our twelve sessions with experts in this cycle of the Re-City platform, organized by the Catalunya Europe Foundation in collaboration with BBVA and with the support of Barcelona City Council, the Metropolitan Area of Barcelona and the Department of "Territori i Sostenibilitat" from Generalitat of Catalonia.

Maher is an expert in pollution and health and director of the Lancaster Environment Center. Her presentation was met with great interest and questions rom the conference's audience. The conference was moderated by Xavier Rodó, Re-City scientific advisor and researcher at ICREA, and "Climate and health" at ISGlobal Barcelona's program manager.

Nanoparticles are a threat to public health

Barbara Maher specialises in the study of polluting nanoparticles and their effects on human health. Known as PM (or “particulate matter”) by the scientific community, these are very thin, light-weight and therefore dificult to detect particles present in the atmosphere. This makes them very dangerous, as they can easily penetrate the human body. In fact, they can reach organs such as the heart, liver, kidneys or even the alveoli of the lungs via blood flow through the respiratory system. They can also directly reach the brain through the nose. This is demonstrated in Maher's research establishing a relationship between nanoparticles and neurodegenerative diseases such as Alzheimer's. In the brains of some patients particles from the exhaust pipes of diesel vehicles have been found.

According to Maher, "this is a huge threat to public health, but the problem is that there are still no environmental networks to measure nanoparticles because the European Union has not established any regulations in this regard". The smaller these particles are, the more easily they enter the body. Their toxicity depends on their origin, composition, size or shape (they can be rectangular, round or spherical). Most of them are loaded with carbon, are rich in metals and come mainly from industrial areas, exhaust pipes, additives added to fuels or from the wear of brakes and vehicle engines, as well as combustion from maritime transport, airplanes and railways. At the same time, they are very magnetic. This can be demonstrated by taking a leaf from a tree on a street with a lot of traffic, which will be covered in magnetite nanopaticles from vehicle exhausts.

An increase in cases of neurodegenerative diseases in young people

One of the conclusions of Maher's research is the relationship between nanoparticles and diseases such as Alzheimer's, shown through the examined presence of metals in the brains of some patients. Up until recently, it was thought that magnetite, which is a contributor to the development of Alzheimer's disease, was formed within the human brain. However, thanks to Maher's research, it is now evident that there is an external origin in pollution, leading to a large concentration of iron that can cause sudden brain tissue death.

In the case studied in Mexico and England, metals such as carbon and titanium or even very rare metals such as cobalt and platinum have been found in the brain. Another very worrying fact is that there are more and more cases of symptoms in young people, such as a 3-year-old boy who had magnetite in his heart and brain tissues. Maher highlighted a recent study conducted in Barcelona by ISGlobal researcher Jordi Sunyer on the effects of pollution on children. According to this study, prenatal exposure to air pollution is associated with changes in the child's brain related to behavioral disorders.

Alzheimer's and other neurodegenerative diseases have usually been associated with older people, but this is beginning to change. Undoubtedly, pollution is a potential risk factor but there are others such as a person's genetic constitution, diet, brain activity or cognitive reserve, which influence the development of the disease.

Electric cars and green barriers to stop pollution

Barbara Maher advises against living in close proximity to streets or on roads with more traffic. According to a study conducted in Canada, living within fifty meters of a highway increases the risk of receiving contaminating particles from 7 to 11 percent. For this reason, Maher supports the use of electric vehicles to reduce pollution and the introduction of well-located green areas and trees for creating natural barriers that protect homes and buildings from polluted air. This can be a very effective measure, as demonstrated by Maher's experiment at Lancaster University. Silver birch trees were planted in front of a group of houses, and the results showed that houses behind the tree line enjoyed better air quality. This was proved by measuring the dust accumulated on the TV screens in the houses, showing that the concentration of nanoparticles inside these houses was lower than in houses without trees. Barbara Maher recommended planting the Thuja Plicata, a species native to the United States that is very effective at capturing these types of particles. She also advised taking care with poorly sealed chimneys, and reducing the use of laser printers that are often pockets of toxic nanoparticles.

Finally, Barbara Maher, who has received many awards for her work but no subsidies or public assistance to carry out research, complained about the lack of institutional support and warned of the risks of not acting. Therefore, she asked governments to accelerate the changes and take urgent action, stressing that doing nothing when we already have the knowledge will lead to decreased intelligence in human beings as a species and an increase in cases of dementia and other diseases.