The impacts of isolation and social distancing on air quality, as shown by ongoing research around the world and in Brazil, show that the reduced circulation of pollutant-emitting vehicles during the pandemic period brought benefits in reducing pollution. However, unlike this trend, the air quality in the Campinas region suffered a worsening, with an increase in the concentration of pollutants, according to a study conducted by researchers from the Center for Meteorological and Climate Research Applied to Agriculture (Cepagri) at Unicamp. The consequences, they assess, are environmentally worrying and to the extent that they can contribute to weakening the health of the population.
The researchers checked the air quality in the municipalities of Americana, Campinas, Limeira, Paulínia and Piracicaba. Contrary to what they expected, they saw that there was a significant increase in the concentration of pollutants in the period between March and July. To understand why this occurred, they analyzed the weather conditions. The autumn and winter period, as noted, is the driest since 1990, when Cepagri began measurements, with a volume of rainfall below expectations, which makes removal difficult. of pollution.
However, climate conditions alone would not explain the increase in the concentration of pollutants. Therefore, they focused on cases of fires and realized that, in addition to the low volume of rain and relative air humidity, there was also an increase in these fires. Using data from the National Institute for Space Research (INPE), 147 fires were detected within the limits of Campinas alone, between March 24th and July 31st. As a result, more polluting elements are released into the air.
“We checked the weather conditions and it was a period that had a very strong drought, especially in April, which contributed to the concentration of pollutants because one of the mechanisms for reducing atmospheric pollution is rain, through what we call wet deposition. But this was insufficient to explain the increase in pollution and we decided to look at it from the perspective of fires. We saw that there was in fact a very large number of fires, greater than in recent years”, assesses Bruno Bainy, Cepagri meteorologist who led the study.
He also points out that the concentration values of pollutants in the Campinas region, which involved the cities of Limeira, Piracicaba and Americana, in some cases exceeded the limit values indicated by the World Health Organization (WHO). "A striking example of when pollution exceeded these WHO thresholds was on May 1, when fine inhalable particulate matter reached an average concentration of 37 micrograms per cubic meter - 50% above the limit." For this material, the WHO stipulates an average concentration, for 24 hours, of 25 micrograms per cubic meter.
With the relaxation of the quarantine, as the region enters the yellow phase, Bruno points out concern about a worsening of the situation, as there will be an increase in vehicles emitting pollutants on the streets.
Air quality and health
Poor air quality has a negative impact on people's health, which is even more worrying during a period when a virus is circulating that has the potential to affect the respiratory system. “There is the environmental issue, but also the health issue. It is even more worrying when applied to the context of the pandemic of a disease that in some cases causes Severe Acute Respiratory Syndrome, pneumonia and lung deficiency”, says the researcher.
Studies that relate the severity and mortality of Covid-19 to the air condition, he points out, have been carried out in countries such as China, India and Italy. Preliminarily, they signal a parallel between severe forms of the disease and higher mortality and regions with higher levels of pollution. “We still cannot measure how much these high levels of pollution may have affected cases of worsening and mortality from Covid-19, but we have studies that say that we most likely had more deaths and more serious cases of Covid-19 depending on the conditions environmental pollution”, he says.
He cites as an example research carried out in northern Italy, in areas with a higher concentration of nitrogen dioxide, which according to the author increased serious cases of the disease. In China, studies also show that there is an increase in mortality in regions where pollution by particulate matter (polluting substance) is highest.
Urgency to change habits
Cepagri researcher Ana Maria Heuminski de Ávila, who also conducted the study, indicates that, to change this situation, it is necessary to change the culture of cleaning land with fire, as well as the habit of burning garbage. “There is a worsening of air quality and health due to the cultural issue of setting fires to clear land. It is a cheap and simple way, but it has a huge impact on health and which people, due to ignorance, often end up maintaining.”
The weather conditions, he explains, are favoring the spread of fire and, therefore, this habit becomes even more dangerous. But in any condition, says Ana, fire causes smoke and pollutes the air, and this habit needs to be changed. “We need to raise awareness at this point in the cultural issue, because there is an exposure of people going out and moving around exposed to poor air quality,” she says.
Habits such as throwing cigarette butts on the ground also need to be changed, as, in addition to causing pollution, they can start fires, as seen on roadsides.
In addition to Cepagri researchers Bruno Bainy and Ana Ávila, professor from the Faculty of Medical Sciences at Unicamp Ilma Aparecida Paschoal also participated in the study.
