The pollution that causes one in five deaths worldwide

The air pollution generated by the combustion of fossil fuels because coal and oil have caused at least 8.7 million dead worldwide in 2018, according to a new study. Yes indeed, one in five deaths in the world that year, it was due to pollution caused by emissions from power plants, factories and vehicles, among other sources.

The death toll is considerably higher than previous estimates. “Initially, the data surprised us,” he said. BBC Mundo Eloise Marais, professor of physical geography at University College London, and one of the authors of the study published this Tuesday in the journal Environmental research.

“Previous studies, depending on which one is considered, estimated the number of deaths worldwide from air pollution from various causes at four to five million people per year. Our study found that the number of pollution deaths from burning fossil fuels alone is double previous estimates», He assured.

The study is the result of a collaboration between scientists from Harvard University and three UK universities (Birmingham, Leicester and University College London). Previous surveys were based on satellite observations and area to estimate the annual average global concentration of particulate matter. However, these observations they cannot determine whether the particulate matter comes from fossil fuel emissions or other sources such as dust or forest fires.

“With satellite data, you only see part of the puzzle”, said another of the study’s authors, Loretta J. Mickley, researcher at the Harvard School of Engineering and Applied Sciences (SEAS).

In the new study, scientists used a different tool, GEOS-Chem, a global model of atmospheric chemistry, whose accuracy has been validated by observations on the surface and from airplanes. GEOS-Chem has high resolution Thus, the researchers were able to divide the planet into segments as small as 50 km x 60 km and study the pollution in each of them individually.

“Instead of relying on the averages of large regions, we wanted to map the contamination on different sites where people live, to find out more exactly what they are breathing, ”he said. Karn vohra, a researcher at the University of Birmingham and another of the study’s authors.

Marais pointed out BBC Mundo: “We use a detailed model of all the processes in the atmosphere that lead to the formation of air pollution and We were able to separate the different contributing factors and isolate pollution from fossil fuels only“.

The next step was to determine the impact of mergers of air pollution in human health. “For that, we use a statistical model that relates air pollution concentrations to the number of deaths, so if you live in a region with very high concentrations of contamination will be more sensitive to premature mortalitySaid Marais.

“The model was very recently updated with new epidemiological studies carried out by the Harvard School of Public Health. These studies have been carried out, for example, in regions with high concentrations of pollution such as China, and others at much lower concentrations in Europe or the United States. With this new information, we found that the negative impact of air pollution due to the combustion of fossil fuels is much worse than what we knew“.

The study provides a better understanding of the impact of calls PM2.5 particles or particles 2,5, which result from the combustion of fossil fuels. These particles are less than 2.5 microns in diameter, about thirty times smaller than the diameter of a human hair.

“These are very, very small particles that are in suspension. And when we breathe them in, they’re small enough to go really deep into our lungs.. The main health consequences of exposure to these particles are lung and heart disease, but there are many other impacts, ”Marais explained to BBC Mundo.

“Scientists find that Every organ in our body is sensitive to the harmful effects of air pollution. Recent studies have shown, for example, the impact of this pollution on sight, as well as its contribution to a reduction in cognitive abilities and at an increased risk of dementia ”, Tenuous.

The new study doesn’t specifically distinguish the impact of pollution on children, but previous research has shown that polluted air, in addition to being able to cause conditions such as asthma, affects neurodevelopment and cognitive ability minors.

According to estimates from the World Health Organization (WHO), 600,000 children died in 2016 from acute infections lower respiratory tract caused by polluted air.

The highest number of deaths due to pollution from fossil fuels has been recorded East Asia.

The researchers concluded that In this region, which includes China, about a third of deaths were due to pollution from the use of fossil fuels to generate electricity in factories, homes and vehicles. In the United States and Europe, these emissions caused about 10% of deaths.

In the case of Latin America, “The proportion of deaths from air pollution compared to China and India is lower. This is in part due to lower concentrations of contamination and lower population densityMarais pointed out and explained, “China and India, for example, have large coal-fired power plants, and coal is burned for energy in homes. “

Marais pointed out BBC Mundo that the 10 countries with the highest proportions of deaths attributable to air pollution from fossil fuel combustion in Latin America are Mexico (10.7%), Chile (10.3%), Guatemala (9.2), El Salvador (9.1%) and Venezuela (8.6%), Peru (8.5%), Dominican Republic (8.1%), Colombia (8.1%), Ecuador (7.2%) and Argentina (6.6%).

“Our study did not specifically examine the cases of each country, but I suspect that in the case of Latin America, vehicle emissions are an important factor of pollution, because in other countries like Europe and the United States, emission standards. “, He assured.

The new study shows the importance of decisive action at political level, according to the researchers. “Our research adds to the growing evidence that air pollution from continued reliance on fossil fuels is detrimental to global health,” Marais said.

“We cannot continue to depend on fossil fuels when we know that the impacts on health are so serious and that there are viable alternatives to cleaner renewable energies ”, he concluded.

BBC Mundo