Air pollution increases stroke risk

Perjantai 7.10.2022 klo 13:44 - Mikko Nikinmaa

Today, only climate change effects of fossil fuel burning get attention. While climate change is undoubtedly the ultimate stress, it does not seem to reach the minds and be accepted by many people even today when the heat waves, hurricanes, floods and wildfires all testify that climate change is happening. The people with the highest percentage of climate sceptics are also the most susceptible to stroke: overweight, with low education, not exercising and driving a lot. They are not likely to be worried about something that may happen to the next generation or to other people as long as they can live their comfortable life.

But they may get stroke! That is something they are worried about when they drive to work in the congested highways of towns with high nitrogen oxide and elevated small particle levels. In a recent article in Neurology, Tian et al. (DOI: 10.1212/WNL.0000000000201316) showed quite conclusively that this kind of air pollution increases stroke risk. Earlier studies have shown that air pollution causes all sorts of lung-related problems. Thus, there is quite clear evidence that fossil fuel use should be stopped even if one is only worried about one’s own health and wouldn’t care at all of the well being of future generations.

Kommentoi kirjoitusta. Avainsanat: climate change, fossil fuels, climate sceptics, nitrogen oxide, traffic

Coronavirus has significant associations with air pollution

Perjantai 24.4.2020 klo 16:48 - Mikko Nikinmaa

The incidence of coronavirus infections has been lowest in islands or island-like areas (e.g. Australia, New Zealand, South Korea, Taiwan, Finland, Iceland, Alaska). Generally, they are sparsely populated and not important for through-traffic. However, both Taiwan and South Korea have high population densities. The low number of coronavirus infections in South Korea has usually been explained with early onset of restrictions and early start of intensive testing. That interpretation is not entirely convincing, since early onset intensive testing has also been done in places with high counts of coronavirus infections. Further, significant differences in coronavirus-induced mortalities occur between areas with high numbers of coronavirus infections.

Two articles published in the Science of the Total Environment have now, in my opinion, completely clarified both these outstanding issues. Both the incidence of infections and the lethality of infections is increased by air pollution. Especially nitrogen dioxide but probably also ozone and particulate matter increase both the incidence of coronavirus infections and the mortality caused by them (Zhu et al. Science of the Total Environment 727 (2020) 138704; Ogen Science of the Total Environment 726 (2020) 138605). In every sparsely populated place also the nitrogen dioxide level is low, but it is quite low also in Taiwan and South Korea, since the pollution does not stagnate in the area. In contrast, the polluted air remains in Lombardia and Madrid area, where coronavirus cases and mortalities abound. Also, Paris, London and New York area likely have high nitrogen dioxide level – and all have high number of coronavirus mortalities. In contrast, at least partially the low coronavirus mortality in Germany associates with relatively low nitrogen dioxide levels even in the densely populated areas.

Thus, air pollution, to a large extent because of car traffic, has significant connections with coronavirus infections. They are symptoms of the same problem, our overuse of the planet. Population bomb, talked much of in 1960-1970’s, increases the likelihood of future pandemics. An Indian author pointed out that because of the decreasing space for wild animals, their interactions with man may cause the birth of next pandemic in India ( S. Minhas, Could India be the origin of next COVID-19 like epidemic?, Science of the Total Environment (2020),

Kommentoi kirjoitusta. Avainsanat: population growth, pandemics, car traffic

Ecotourism - can tourism ever be ecological?

Keskiviikko 18.1.2017 klo 12:30 - Mikko Nikinmaa

During recent years something under the name ecotourism has been the most rapidly increasing trend in tourism. The name has been used of all kinds of trips when the destination has been outside the normal tourist attractions and the object has been to visit some nature site. Thus, in many cases for example cruises to Greenland and Antarctica are advertised as ecotourism. In those instances it is easy to say that the travel is far from being ecological. In the easily disturbed Arctic and Antarctic ecosystems such cruises are already one of the biggest causes behind environmental contamination.

Similarly, safari tours to see the big game in South Africa are named ecotourism. While every effort can be made to diminish the disturbance caused to the animals, the mere approach is more or less the same as the reason for creating zoos. Actually, in my opinion the major difference is that when zoos were founded, a normal person could not travel to the places where the animals live in their natural environment, whereas with affordable air traffic it is possible today.

Ecotourism is defined as "responsible travel to natural areas that conserves the environment, sustains the well-being of the local people, and involves interpretation and education". There are two things that make ecotourism, in my opinion, impossible. The first is that the sites can be reached only by, e.g. air or boat transport (and local car transport) which generate fossil fuel pollution. The second is that if a nature site becomes popular, environment will be necessarily affected.

There are, however, a couple of very good things which result from nature tourism (note that I use this word pair instead of ecotourism). The incentive for governments to save the habitats with tourist interests increases. The local people can get the financial benefits from the tourists.

In any case we are not talking about ecotourism, because tourism cannot be ecological, but nature tourism, which can have beneficial effects in addition to the negative environmental effects that tourism necessarily causes.

Kommentoi kirjoitusta. Avainsanat: air traffic, transport, environmental effects