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Forest fires threaten the health of Amazon populations


Graça Portela (Icict/Fiocruz)


The year of 2004 was marked by the 270,295 forest fires in Brazil ( the peak number for forest fires in the 21st century. At the time, there were 145,251 seats of fire in the Amazon biome alone, which accounts for approximately 40% of the national territory occupied by the States of Acre, Amapá, Amazonas, Pará, Rondônia, and Roraima, as well as parts of Maranhão, Tocantins and Mato Grosso.

According to data from the National Institute for Space Research (Inpe, in portuguese) Fire Monitoring Satellite Program, there were 275,120 forest fires throughout the Brazilian territory in 2017, a 1.78% increase. However, the Amazon biome showed a slight decrease compared to 2004 with 132,296 seats of fire. There is not much to celebrate though – fires often increased in natural forest areas where they didn’t use to reach.

This happens in the State of Rondônia, in Northern Brazil. According to data from the sentinel site for the National Observatory of Climate and Health, the state registered a growth of forest fires from 2012 to 2017:

Amnesty to deforesters

The sentinel site is located in the capital of Rondônia, Porto Velho, one of the most affected areas by forest fires in the Amazon region. It is coordinated by the Fiocruz researchers Sandra Hacon, from the National School of Public Health (Ensp/Fiocruz), and Christovam Barcellos, from the Institute of Scientific and Technological Communication and Information in Health (Icict/Fiocruz).

According to Hacon, deforestation has risen continuously since the Brazilian Federal Government gave amnesty to deforesters and the colonization process, through the so-called National Integration Program in the 70s. “Such an intense deforestation process calls on the wood and cattle breeding industry which, in turn, destroys the Amazon soil intensely and extensively with deforestation that leads to fires,” she explains.

But how can fires affect the health of regional populations? Hacon states that “particulate, microscopic matter consisting of several compounds and elements is released. This is what mainly affects the health of Amazon population.”

She draws attention to the high deforestation rate in Rondônia - almost 70% of the territory had already been cleared for pasture and crops. This carries “increased rates of respiratory diseases, especially in vulnerable groups - children and the elderly - and people with previous illnesses both related to respiratory and cardiovascular diseases.”

The researchers Poliany Rodrigues (Ensp/Fiocruz), Eliane Ignotti (Unemat and UFMT, both in Mato Grosso), and Sandra Hacon conducted the 2013 study Spatial and temporal distribution of burning and hospitalizations for respiratory diseases in children in the state of Rondônia, 2001-2010, drawing attention to the fact that “areas with increased number of fire are different from those with higher hospitalization rates for respiratory diseases. Which can demonstrate how important it is to transport such particulate matter over long distances in the Amazon.”

The article also states that “exposure to pollutants from fires does not necessarily coincide with where fires occurred, which is why sources of heat should be used as indirect indicators of exposure.”  In addition, the researchers recommend a “monitoring of particulate matter from fires in Porto Velho micro-region”, noted in this study as a critical area because of the highest concentration of seats of fire.  Amazon health surveillance programs must implement sentinel areas to monitor health indicators on impacts for human health due to fire pollutants.

To get an idea of the problem, fires are more frequently started between July and October, peaking in September. Nasa’s Modis Terra Acqua satellite images from September 9 to 26, 2017 capture the region’s situation:

Icict/Fiocruz website collected data from the Hospital Information System of the Brazilian Unified National Health System (SIH/SUS), Datasus, on respiratory diseases from November 2012 to 2017 in the region. Similarly to the researchers’ study, it draws attention to the number of children under four years old hospitalized for respiratory diseases:

Respiratory compromise

A 2015 study conducted by Beatriz Fátima Alves de Oliveira at Ensp/Fiocruz and advised by Hacon, Air pollution and its effects on children's health: A study on oxidative stress biomarkers in children and adolescents in the Brazilian Amazon, reaffirms the concern of researchers with the effects of fires. Her study examined children and adolescents from 5 to 17 years old living in Brazilian Western Amazon, particularly the city of Porto Velho, and showed one of the following results: “air pollution is associated with several mechanisms, including airway inflammation, systemic inflammation and neuroinflammation, endothelial dysfunction, coagulation, atherosclerosis, alterations of the autonomic nervous system, DNA damage and redox imbalance.”

The studies of Porto Velho Sentinel Site, coordinated by Sandra Hacon, have helped researchers from USP, UFRN, Fiocruz and UFRJ, as well as UFRO, essential to the study’s logistics, to demonstrate the impacts of fires in the Amazon forest. They can be read in the article “Biomass burning in the Amazon region causes DNA damage and cell death in human lung cells” co-authored by the USP Institute of Physics researcher Paulo Artaxo, considered one of the top authorities for climate analysis.

In the study, researchers provide evidences that “when burning particles reach the lungs they increase inflammation, oxidative stress and cause genetic damage in human lung cells. DNA damage can be so severe that the cell loses its ability to survive and dies. Or it loses cell control and starts to reproduce disorderly, evolving into lung cancer,” as reported by the study's lead author, the USP researcher Nilmara de Oliveira Alves. Researchers collected samples of the material released by burnings in the atmosphere near Porto Velho, one of the areas worst affected by fires in the Amazon.

The article provide scientific evidences on the association between burnings and the risk of cancer. Nilmara consider children the most vulnerable group exposed to fire smokes, and explains: “the population being exposed to smoke is at a higher risk of developing lung cancer and worsening pre-existing conditions such as asthma, bronchitis, etc.” For her “children is one of the most vulnerable groups, undoubtedly. Accordingly, recent studies conducted by the WHO (the World Health Organization), proved that 1.7 million children under 5 years old die worldwide annually because of environmental pollution, and air pollutants are a major culprit.”

The USP researcher, who currently works in France in partnership with the International Agency for Research on Cancer with emphasis on environmental impact studies, reiterates the risk of fires to the population “Such negative effects are explained by the very fine particles of smokes capable of reaching the respiratory system, the lung alveoli and contacting the bloodstream, thus being harmful to health. In addition, emissions contain many carcinogenic compounds and people inhale these compounds involuntarily, then contributing to lung cell damages.”

The researcher Sandra Hacon states that the effects on the health of the population are often not immediate. According to her, “it will depend on the amount of emission and concentration of the particulate matter in the atmosphere. Sick people presenting the impact of burnings and atmospheric pollution either already had health condition, are older or children,” she explains. Hacon believes that people who already have respiratory problems and do not use the medications will experience effects more quickly. People who already have respiratory problems and use the medication will possibly experience them later and, sometimes, not experience them at all,” she says.

Necessary change

Hacon warns that pollution doesn’t choose social class; however, she emphasizes that the most vulnerable populations end up being the biggest victims of environmental pollution “because if you have a respiratory or an infectious diseases, exposure to atmospheric pollution will worsen these diseases as there is no ventilation in the house, many people sleep in the same room, he/she doesn’t have access to health services - not only because he/she lives far away but often because he/she lacks income to commute to health facilities in the capital which would have more resources - and because of increasingly higher social inequalities.”

Christovam Barcellos agrees. In his opinion, the data and analyses about the current situation of Porto Velho only highlight the importance of studying climate and its relation to health “researchers have been raising several evidences that climate is changing due to human activity on Earth. Some of the effects are already being felt in the health area, and mobilizations around this theme are growing. The media and civil society are increasingly aware of this new, threatening problem.”

However, population and researchers are already alert and starting a mobilization. After we finished this article, draft information - as per news published by major newspapers - sent for comments from reviewers of the Intergovernmental Panel on Climate Change (IPCC/UN) report on global warming stabilization at 1.5 ºC stated “the need to implement an unprecedented level of transformation in the (industrial and agricultural) production area if humanity proposes to avoid the radical changes caused by climate change.” This only reinforces the need for instruments as the National Observatory of Climate and Health allowing to share information capable of changing this reality with the population, managers and other researchers.

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